FR2803884A1 - Electricity production using a solar heat source glasshouse or water vaporization, to drive hot air balloons whose rate of ascent is used to drive an electric motor - Google Patents

Abstract

The hot air balloon has two circular light rigid half shells about 250 meters wide which but up against each other when the balloon is not inflated. Inside these shells is a folded balloon envelope. In the top half shell are two 100 meter wide light hydrogen or helium gas chambers with convex lens covers and in between these two chambers is a 20 meter wide air output chamber. Attached to the top half shell are insulated tethering cables. In the lower half shell are two rolled up skirts for which are unrolled in calm weather. The central part of the lower half shell forms the base of the balloon and is of the same material, in this base is a warm air inlet tube. When deployed the canopy forms into a large dimension cylinder, 220 meters wide, between the two half shells. The fluid motor is atmospheric air heated by contact with a energy source. The piston is a hot air balloon whose ascent extends over several kilometers using the high troposphere as cooling source. The tare of the balloon is zero or negative due to the use of auxiliary balloons filled with hydrogen of helium. The best efficiency is produced by first part of the ascent made with a constant air quantity and a rising volume and the second part with a constant volume and decreasing quantity of air. Further claims include balloon filling, electrical power generation. balloon ascent and descent, etc.

Description

<B> <U> I. GENERAL PRINCIPLES The present invention aims to contribute to the fight against the greenhouse effect. It describes, primarily, a new way of producing electricity of solar origin. Incidentally, it can also contribute to the energy efficiency of existing electricity generation methods (thermal or nuclear power plants), as well as to the electrical valorization of other energies available at relatively low temperatures, such as geothermal energy.

<B> <U> A. Description of the principles used </ U> </ B> <U> 1. Nature of the </ U> fluid <U> engine </ U> In terms of solar energy (besides hydraulic energy), the most explored tracks are: biomass, wind energy, solar photovoltaic , systems with spherical or cylindrical focus, solar pools. (In terms of energy savings, there is also a renewed interest in airships in the field of non-urgent airfreight - eg delivery of machines to places that are difficult to access. this function, and for controlling large gas shells lighter than air).

The invention is based on another principle, borrowing from wind and solar pools. The energy sensor is, as for focusing systems, a black body exposed to the sun (without focusing, because, since the objective is not to turn a turbine, it is not necessary to exceed 100) , the working fluid is, as for the wind turbine, the atmospheric air dry or wet, and the phenomenon making it possible to pass from one to the other is, mainly, the law of the perfect gases (an increase of temperature causes either a constant pressure expansion or a constant volume pressure increase).

Air turbines are little used because, for the energy per m 'to be significant and the flow in m3 / s is important, it would be necessary that the pressure is significantly higher than the atmospheric pressure, which would require a compression effort antagonistic with the effect of relaxation that we want to capture.

These difficulties related to turbines do not however prevent the use of air as a driving fluid if two conditions are met: a large volume and a piston whose stroke is long. <U> 2. Use of balloons </ U> In the case where there is even a very large volume and a piston with a very long stroke, one can be satisfied with a very small difference in pressure, such as that resulting from the difference in density of two columns of air, one or several hundred meters high, with temperature differences of a few tens of degrees. This is the case with large balloons (typically several hm 'to several tens djjm', that is to say several thousands to tens of thousands of tons of air, and a thrust of 1000 to 10 000 t, and a power of a few tens of MW for speeds of the order of m / s), filled with air heated to a temperature of 50 to 80, or by passing through a canopy lined with black bodies of a surface of the order of the km 'and benefiting from the greenhouse effect of the windows, or by vaporization of water from 60 to 90.

The course of these "pistons" is of the order of several km, that is to say, the thickness of the useful tropospheric layer, where the atmospheric pressure is not too low. The temperature curve as a function of the pressure, ie of the altitude, respects an adiabatic expansion law, which is also the case of the external atmosphere if it is in thermal equilibrium vis-à-vis of convection. The ratio of the internal density to the external density evolves in the most favorable way in the case where the external atmosphere is dry (absence of clouds, otherwise useful to have a good sunshine) while the air of the balloon is wet: in this case, one domesticates in fact a cumulus artificial sky, to capture the ascensional force.

In the less favorable case where the behavior of the internal air and the external air is the same, we already have an identical relation between pressure and temperature (PI-r.T7 = coast for a dry air), therefore a ratio of density between the inside and the outside which remains constant, and a pull up which decreases only to the extent that the mass of air contained in the balloon decreases.

By offsetting the flare of the hot-air balloon with complementary balloons, inflated with helium or hydrogen (with fireproofing), the tractive force may be equal to or greater than the Archimedes' thrust of trapped hot air (but loses the equivalent to the descent - likewise, the effect of the mass of the cables hanging on the balloon is canceled between the ascent and the descent).

The optimization of the factors of production leads, in a first phase of the day, to accept that the hot air balloon expands under the effect of the pressure drop, then, in a second phase, to release hot air, because an additional volume of ballooning would not be profitable over the last km.

Continuous production of electrical power, and even constant power (or perfectly meeting the demand of a network) is possible if different balloons take turns (including at night thanks to the storage of daytime heat and the fall of the outside temperature). Each balloon is connected to one or more DC machines, operating as generators for climbing and as motors for descent. The conversion of these DC currents into AC acceptable by the network can be achieved through one or more DC motors, driving an alternator.

3. Site <U> of implantation </ U> the best <U> adapted </ U> to the hot air balloon race As we have seen, it is preferable that we have outside the balloon a decrease in temperature with the altitude corresponding to the law of the dry adiabatic gradient. We must therefore seek to implant the canopies in areas where the air is dry and where there are regularly air movements with a non-zero vertical component. Since the global atmospheric circulation is organized in convection cells, it is better to be at the edge of these cells, rather than in the middle, where the movements are essentially horizontal (which also raises problems with wind balloons and difficulties in getting them back over their starting base). Favorable areas are called "calm".

The most indicated are the "subtropical calms", where there is at the same time dry air, needs of fresh water, vertical convection, and little horizontal convection. Their only drawback is to be surmounted by jets currents ("jet-streams") at altitudes of which (10 000 m and above) it is excluded that balloons can venture. The most favorable regions are therefore: southern Mediterranean, Middle East, Mexico, Australia, South West Africa, certain regions of South America.

The development of the present invention can be envisaged in these regions in the following economic logic: it is in many cases of fossil fuel producing countries. Their use should quickly, given the greenhouse effect, be heavily penalized (C02 tax, or any equivalent mechanism: permit to pollute exchangeable, etc.). The existence of an alternative resource well adapted to these countries could make this evolution, indispensable but still subject to difficult international negotiations, more easily acceptable (the export of this energy could be facilitated by the development of combustible).

<U> 4. Use of humid air and combination of the seawater desalination function </ U> All the techno-economic conditions required (areas located at an average distance from fairly populated cities, with a stable and sunny climate, in which the sun is near the zenith, and where the value of the bare land is low), is filled by a number of coastal deserts. It is therefore justified to try to associate the electricity production function, described above, with the desalination function of seawater. This can be achieved by means of "showers" in which salt water is evaporated in the air, a motor fluid, which is filled with hot-air balloons. This increases at the same time, at constant balloon volume, the production of electricity, for various reasons, the most important of which is the fact that arriving at an altitude where the cooling leads to the condensation of water, the balloon is transformed in cloud, but whose air circulation is blocked at the top and captured by its envelope. The heat generated by this condensation greatly limits the decrease of the temperature with the altitude, whereas this decrease is stronger outside the balloon. The temperature differential with respect to the outside therefore increases, which reinforces Archimedes' thrust of the balloon.

The recovery of fresh water thus condensed can bring additional revenue of about 10% of the electricity produced.

<U> 5. Production of hot water used </ U> The heating of the air by evaporation of rather hot water (60 to 90) is in itself a source of savings. Quite large amounts of water at this temperature are often available without being upgraded or can be produced cheaply. This is the case for the cooling water of thermal or nuclear power plants. Geothermal deposits that are relatively distant from cities can also be valued in this way.

Finally, the capture of solar energy can also be done using water of the same temperature range, thanks to the technique of solar pools. The layer of water to be heated, of high salinity, is at the bottom of a basin; it is thermally insulated from the atmosphere by other layers, including, on the surface, a layer of cold water, which loses little heat by evaporation, and low salt, all being stable relative to gravity, and therefore anticonvective The bottom water layer, accumulating heat, allows a night operation of the whole.

The invention could be considered as a variant of solar pools. The differences are important, however, and result from the fact that many cycles, often closed, are strongly modified and frequently transformed into open cycles.

In conventional solar pools, hot water from the bottom of the basin gives up heat in a heat exchanger. Here, one can use its own vaporization to fulfill this function, with probably a better performance. The driving fluid of the solar pools also performs a closed cycle (it may be water under a pressure less than one atmosphere, or any other fluid boiling less than 100 C), imposed by the existence of the turbine. Here, the driving fluid is the air of the balloon, which is released at high altitude (at a temperature that plays the role of cold well cold), the fresh water being recovered alone. <U> 6. Prior vaporization of the water at constant volume The main characteristics described above (use of water as heat transfer fluid and air saturated with water vapor as the driving fluid, without turbine; using large devices, including large gas envelopes, operating in coastal deserts, at relatively low pressure, at limited speeds, from a low-temperature hot source, but using a cold source colder than usual, and finally producing significant power and fresh water in significant quantity) are found in the following complementary device The motor fluid is again the air, but, so as to improve the yield can be harvested at the end of the night, at the coldest hour (and which is indeed very cold in the deserts), and store it for the day under "covers" reflective the solar radiation and which either close natural reservoirs (gorges, cirques, ...), or deform in dome like tarpaulins used for green silage, but here with dimensions that can go up to the tenth of km.

An "air plant" consists of rooms capable of withstanding pressure differences of the order of 1/2 atmosphere and equipped with a large piston (several hundred m2) at each of their two ends. . One of these pistons, which will work only under limited pressure differences, and can therefore be driven by a commonplace process (pneumatic or hydraulic cylinders, sealing provided by bellows) allows admission and exhaust, every minute or so, in tens of thousands of meters, air, motor fluid.

This air, initially cold (; e 0 C) and / or precompressed by the return of the engine piston, is heated as in point n 4 above (hot water showers), so that its temperature rising approximately at 60 ° C., it reaches a pressure of the order of 1.2 atmospheres, to which is added the saturation vapor pressure of the water (0.1 to 0.2 atm). It can then relax, in a big fraction of a minute, by pushing the piston engine with a force measuring in 107 N on a run of a few tens of meters. We find a power of the order of one to several tens of MW.

This power is continuously produced when there are several "cylinders" so equipped with pistons, and who work in turn. By coordinating these cylinders and collecting these powers in a manner analogous to that used for two- or four-stroke combustion engines ("spark-ignition engines"), a single, roughly uniform circular movement is obtained, resulting in regularly a single electrical generator (or three machines: DC generator, DC motor, alternator, if you want an optimal power supply network).

The humid air has thus undergone a relaxation of about 1.4 atm at 1 atm, without having lost much of its water vapor, it is available to feed the balloons, and to relax thus from 1 to 0.5 atm . The "air factories" are thus intercalated, practically without incident on the sequence of events, between the management of hot water and that of the "artificial cumulus", by bringing a gain in electrical power.

<U> 7. Economic <U> and </ U> Thermodynamic Efficiency </ U> Although the working fluid performs an open cycle, the balloon performance is not unrelated to that of a Carnot cycle, provided that it is not calculated by taking the ambient air as a cold source, but the high altitude air in which the balloon empties. This yield is therefore approximately proportional to the maximum altitude reached. With a dry air and a maximum altitude equal to 2/3 of the zo of the dry adiabatic grading equation, ie 5760 m, theoretically a thermodynamic yield close to 18% is obtained.

The use of moist air makes it possible to obtain, at unchanged balloon volume, a higher power even if the starting temperature is lower; on the other hand, the overall yield is lower because of the low recovery of part of the latent heat of vaporization, but this is offset by the much lower cost of capturing the heat of the sun by a solar pool, compared to canopies. This latent heat loss is less with the "air plant" operating with a night air reserve, which allows to add a power of about one third of that of the balloon.

A final yield of the order of half of the above figures (considering the thermal losses at the time of heating of the air or water by the sun) would be lower than that obtained with photovoltaic cells. or systems with cylindrical focus, but on sites where the ground surface is far from being the rarest resource, this criterion is not essential. The important thing is to obtain the lowest capital cost of the kW., And the ultimate objective, a cost (capital depreciation and operating cost) competitive with that of fossil fuels, once their costs properly internalized external taxes (C02 tax).

<B> <U> B. Comparison with competing techniques </ U> </ B> Compared to photovoltaics, the advantage can lie in the fact that the m2 (and therefore the km2), on the one hand canopy (with its foundations, its structure, its basins of water for the storage of heat, and its "black paint") or a fortiori of solar basin, and secondly of hot air balloon envelope (the surface of canvas is lower than that of radiation sensor) cost significantly less than the m2 of silicon, monocrystalline, polycrystalline or amorphous, cut into thin slices and doped. In fact, there is complementarity: photovoltaic photovoltaics, infinitely divisible without loss of economies of scale, has its future in the autonomous production of electricity in places that are difficult to connect to the grid; the system described here is, by nature, a centralized energy. Solar ray focusing systems have two variants. The aim of spherical focusing is to obtain very high temperatures for high-tech applications. The cylindrical focussing makes it possible to heat water to transform it into a fairly high pressure steam, which is well suited to supplying a turbine - alternator pair. Their cost per km 'is however high, on the one hand because of the need for good quality mirrors, and the fact that one must manage fluid circulations in about 1 m of piping per linear meter of cylindrical mirror, about 100 km of pipe per km2. Here, there are simply large circulations of air or water, through much less ramified structures.

The "solar pools", put to use for the present invention, have the same logic of large floor area, compensating for obtaining heat at relatively low temperature, and seeking to obtain a cost per installed kW lower than for systems focusing and high temperature. Their current developments are either district heating, which is perfectly rational, or the production of electricity with turbine. The particularity of the invention is to go to the end of its logic, giving up the idea of working a turbine, that is to say a narrow passage and also limited longitudinally, requiring speeds and high densities not very compatible with the use of low temperature heat. The same remarks apply to the use of the energy of the seas (systems operating between the surface temperature, of the order of 25 C, and that of the bottom of the oceans, lower than 20).

Finally, compared with wind power, the advantage is a much more systematic capture of wind power at its source. In addition, wind turbines operating especially in rough weather, and the system proposed here in sunny weather and calm, there is more complementarity than competition between these two modes of development of solar energy. <B> <U> II. PRODUCTION </ U> </ B> OF ELECTRICITY <B> <U> AND </ U> </ B> </ B> <B> <U> OF FRESHWATER </ U> </ B> <B> <U> LAID OF </ U> </ B> MONTGOLFIERES <B> <U> A. Balloon Structure </ U> </ B> <U> 1. Objectives to achieve </ U> Given the voltages to which it must be subjected as a captive balloon exerting a strong pull up and down empty, the theoretical goal of operation by almost all times, the long duration during which it must be damped, and especially of its dimensions, hot air balloon requires that particular attention be paid to its structure, its catch with the wind, its assembly and its maintenance. The canvas may be subject to special efforts at its various anchor points, if it "slaps" in the wind. It is therefore necessary on the one hand to find a shape, especially when emptied, which avoids such slamming, and on the other hand to distribute the forces (the traction itself being at the maximum reserved for towing cables, or preferably for straps - <B> CE </ B> infra) on the perimeters of each piece (if you want a removable balloon), while creating dissipative structures to dampen shocks and oscillations likely to generate resonances.

The general search for a good energy and financial performance (which requires the greatest possible continuity in production), and the difficulty of predicting dynamic behaviors in unfamiliar situations, will logically lead to approaching the limits of rupture, especially on prototypes. Given the significant costs of the materials used and the imperfection of repair management (which leaves weak points of weakness), these breaks must occur at the assembly of the different parts. Like the attachment of a boot on a ski, this assembly must at the same time hold well under normal conditions of use, and, in case of excessive efforts, yield in a reversible way to protect the other elements whose rupture would be irreversible. . In addition, it must be released without great effort by an action that only the user can cause.

Finally, still in the perspective of prototyping, the construction by modular elements can allow to reuse the elements of a small prototype, to build a larger one.

<U> 2. Choosing a </ U> structure <U> relatively rigid but light </ U> After emptying the hot air balloon of its hot air and except to inflate it (at the top and then as it descends) air approximately the same as that present in the neighboring atmosphere, which requires a device for introduction and pressurization of air, the fact of going down again poses the problem of a floating envelope and flapping in the wind, which , as for the sails of a boat, accelerates the aging of the canvas.

It is therefore necessary that, even deflated, the hot-air balloon presents an outer envelope approximately taut and, if possible, slightly convex.

This is possible if it is constituted around 2 circular armatures delimiting a vertical cylinder (possibly a little big-bellied, with an extensible fabric under the effect of the pressure of the hot air). The dump will consist in bringing these two frames together, and the lateral envelopes will fold, preferably without moving completely towards the center of the balloon, but instead forming folds of about ten meters wide between these two frames. Corrugation primers may be imposed on the fabric, for example in the form of very extensible horizontal beads, filled with helium, fixed to the envelope (inner side) in such a way that they impose on it a part of their curvature; their role would also be to avoid tissue fatigue by folding, at the level of these corrugations in the folded position. Also in order to encourage the fabric to fold in the desired position, the spindles may be slightly variable width. Thus, the narrower places, which will be slightly under tension, will tend to fold first towards the inside of the balloon, whereas the widest passages, which will coincide with the presence of the helium rods, will naturally remain the outer side, their curvature directed inwards (Figs 1 and 1a).

Once deflated, the hot-air balloon will have upper and lower surfaces (disks) approximately identical to their inflated position, and an outer edge consisting of the joining of the armatures initially located on the two ridges of the cylinders. Properly beveled, these frames will allow the hot air balloon to offer a grip on the side wind quite weak, its behavior then being intermediate between those of an airship, the wing of a large sailing boat back to the wind, and a wing of a big plane. This allows to consider, given the number of available commands (one per strap), a functioning even in relatively intense wind.

These circular reinforcements may be reinforced by three to six radii, especially on the upper face, in the center of which is provided a device for controlling the air outlets from the top of the balloon. They should, in normal operation, be subjected only to small stresses, the principal one being a compressive force which is almost constant over their entire circumference. They will be easily assembled and dismountable, given their characteristics developed below.

If it proves very useful that the web of the upper and lower faces is convex, despite the compression of the residual air during the descent, the auxiliary gases (H2 or He) can be distributed in contact lenses. fabric under tension (the internal face being the most tense), able to maintain an aerodynamic profile even losing part of their volume.

<U> 3. Constitution of the solid bricks </ U> Each element of these reinforcements will be an arc of circle whose extremities will be radial faces (thus not parallel) contributing to the stability of the whole as do the stones of a vault and in particular the keystone. The main constraints will therefore be, as a main principle, a compressive stress in the direction of the length of this element, and, on a secondary basis, stresses of recess (in particular of ejection towards the outside) at the level of the connections with the elements. adjacent elements. The best stability will be obtained if there is a regularity of the concordances between these removable solid elements, the removable textile elements (next point) and the straps (or cables) tractors.

Each element can have a width and thickness of 5 to 20 meters, and a length two to three times greater. Given these dimensions, the small stresses undergone, and the fact that it is in any case planned to lighten the whole of the balloon using helium or hydrogen, it is conceivable that these elements ( internal structure + envelope, resistant to or accompanying the pressure drop of the surrounding air, and to fill the rest of the volume of light gas) are almost as light as the air on the ground, which would be a considerable advantage for their manipulation, and would also allow the use of larger dimensions which, in turn, allows to achieve the same mechanical performance with an even lower average density.

Thus, an element with approximately triangular section (because the profile of the frame must have an aerodynamic bevel), 20 x 20 x 50 m allows to use nearly 12 tons of solid material. Under these conditions, a relatively rigid and resistant result seems to be possible, with two options: a strongly triangulated structure (triangulated assembly of elements themselves triangulated, etc.) in resistant and lightweight material (duralumin, carbon fiber, etc. .); we can also imagine using a much more massive structure, made of a material such as expanded polystyrene, where the air would be replaced by helium or even hydrogen (substitute hydrogen for air - unless the normal expanded polystyrene is made with nitrogen - that is to add a fuel but to remove an oxidant, it is not certain that the result is considerably more flammable, it can also be considered, for reasons savings, a polystyrene core with hydrogen, surrounded by a layer of polystyrene with helium).

The techniques proposed here may also interest the industry, renaissant, airship.

The assembly of the different bricks between them can be done by any means that respects the analogy with ski bindings, exposed above. It is however necessary to respect the waterproof envelope of each element. A clip clipping method (tube but without direct contact with him) is for example possible. One can also use the principle of suction cups, developed below.

<U> 4. Textile assembly </ U> The concentration of the stresses on textiles, and hence the risk of breakage, at the level of any discontinuity in a piece of fabric, particularly at their ends but also at the seams, argues for the manufacture of large pieces. Their size can not be that of the balloon itself. It also seems necessary to provide a structure in removable elements, with fasteners whose breaking point is high but lower than that of the canvas itself.

Velcro fasteners may fulfill these conditions, but do not meet the last criterion in 1 <I> ("they must be able <I> to be <I> released without </ I> great <I> effort </ I> I> <I> an action that only the user can cause "). </ I> An adaptation of the zipper principle satisfies this criterion, but it must be verified that it also satisfies that of a reversible fracture. , with a high breaking value and stable over time. Failing this, a solution could be that of fixing by linear suction cups (same function and same sectional pattern as a circular suction cup, but symmetry by translation instead of symmetry by rotation).

Such a connection could be completed by semi-rigid rods, fixed to the canvas, and provided with magnets, sufficient remanence, which would ensure, in normal weather, a completely smooth facade. In the event of a gust of wind, these magnets would give in, then the bond would reform spontaneously, as when separating a double helix of DNA. This device would thus help, on the one hand, to reduce to almost nothing the fatigue in normal operation of the line of slides or suction cups and associated seams, on the other hand to the dissipation of energy in the event of severe turbulence on the textile envelope.

The same principle could be used to manage the delicate period of inflation of the balloon, where it is in an intermediate state between its inflated and deflated states, and where it does not benefit from the wind protections of either of its two states. . The folding of the envelope according to the undulations described above could be maintained by magnetic lines, which would yield only one by one, and only when the internal pressure of the envelope would be sufficient. At no time, the balloon would present the spectacle of a textile envelope left to itself.

The structures described above having a fairly large linear mass, source of deformations of the fabric (in particular those in vertical position), this mass can be compensated by the Archimedean thrust of an expandable coil filled with helium.

As all these devices constitute a significant cost factor, the dimensions of the pieces of fabric will have to remain as large as possible taking into account the constraints of assembly and disassembly.

<U> 5. </ U> Lower <U> Appendix to Use in Weak Wind </ U> The cost of hot air balloon resulting largely from the above devices, which are primarily intended to ensure its longevity in spite of the the action of the wind, one wonders if one could have two possible configurations, one with a relatively high cost and ensuring the quasi-continuity of the public electricity supply service, and the other operating only in stable weather but producing less expensive power.

The answer is positive. The "hard core" of the hot-air balloon consists of the two circular frames described above, as well as the textile casing in cylinder which joins them and which folds between them; it alone can work in windy weather. On the other hand, in stable weather, nothing forbids deploying under the hot-air balloon a wide skirt of inexpensive and little worked fabric, which considerably increases its volume. It is not he who will be subjected to the most important efforts, but the summit of the hot-air balloon, whose pressure difference between the inside and the outside is proportional to the difference in density and to the height of the column. air, from the level where the pressures are equal (ie the base of this skirt) to the top.

This increase in volume may correspond to a larger injection of hot air, and therefore to greater sampling in the heat source (as regards glass roofs or solar pools, there is often more sun and fewer thermal leaks. when there is less wind), but also a longer conservation, within the system, of a mass of air that would initially be introduced into the salt "hard core" and which expands, so overflows the hot air balloon , as the pressure decreases.

On the other hand, once it has completely filled this skirt, the air of the proud montgol in expansion will have to be led to escape by the top, so as not to destabilize the hot air balloon by rising hot air along from his envelope. This device is recalled below, particularly with regard to its contribution to the recovery of soft water (in cases where this feature is developed - in the same circumstances, the skirt may also be provided at its base with a system collection of rain created in the balloon).

<U> 6. </ U> thermal characteristics <U> of balloons </ U> Given its volume and the relatively short duration of climbs, the conservation of heat in the balloon should not pose a major problem. If necessary, convective and conductive losses can be controlled by suspending very light canvases from the ceiling of the balloon, which behave like additional "peels" near the envelope, both at the top and on the sides. If the air, particularly humid, is a significant emitter in the infrared, the peels can be designed to stop this radiation, and the balloon can be covered internally with a reflective material in the same range of lengths. wave. This also has the advantage of allowing, by infrared photography, to locate from the outside a hot air leak.

It is questionable whether climbing the balloon at high altitudes could cause frost problems, which could, for example, block the opening or closing devices of the top of the balloon, the deployment of the skirt described above, etc. It may be necessary to provide a reheat of these mechanisms.

<U> B. Operation of balloons stricto sensu </ U> <U> 1. Position of </ U> U Balloon </ U> Filling </ U> Although it is recommended to use them in areas where, on average, the airflow is more vertical than horizontal, one of the possible difficulties of montgol - proud is the effect of the wind during the start and stowage phases at the time of return. The constraints are therefore cumulative: a management always delicate, despite the arrangements proposed above, filling phase during which the balloon is neither in the completely closed position described above, nor totally inflated; because it is "captive" and the proximity of the ground, which is likely to increase air turbulence and its sand load.

 The last two of these three constraints can be reduced by adapting the structure and the operating mode of the balloon, by analogy with the technique, used in aviation, refueling in flight. This is indeed to avoid the ball proper to get too close to the ground (100 or 200 m). The refueling, that is to say the recharging in hot air, is done by a textile hose of a radius of the order of one or a few tens of meters, attached to the balloon (preferably from its top) . It is guided, by means of free contacts (rings), by the straps or cables outside the hot-air balloon, and its base is collected by a funnel which directs it towards the securing system. It is itself subject to tension and therefore ages quickly, but its area (and therefore its cost), allows a more frequent renewal, because it is much lower than that of the balloon itself.

Thus, the filling of the balloon in any case to be made from a temporary assembly of two pieces (for example two rings, one linked to the ground, the other to the balloon, whose final adjustment would be obtained by attraction ferromagnet), it is preferable that it is not the balloon itself which is subjected to the strong constraints related to the need to fix this tie-down ring which would constitute itself, in particular in case of gusts of wind near the soil, an element of concentration of these constraints, and thus of embrittlement of the fabric.

Another drawback related to the presence of wind is the possibility of large-scale oscillations, due to a resonance phenomenon, towing cables (their eventual replacement by straps requires adapting the device described below). This can not only weaken them, but damage their good entry into the buildings on the ground, and their good winding on the drums, the major risk being an exit from the throat of the first pulley on which they pass. From this point of view, several properly arranged pulleys can "encircle" the cable by occupying all 360 around it.

However, such a device does not fight by itself against the propagation of important vibrations towards the machines. It is therefore necessary to fight specifically against resonance, which conventionally passes by the establishment of fluid damping systems of coefficients adapted to the different resonance frequencies of the cables or straps (which vary continuously since the voltages and lengths also vary. ).

Since the main function of the cables is to be able to translate longitudinally, these damping devices act only transversely. They are therefore interposed between the frame and the "first pulley" mentioned above. Replicas also allow damping at lower pulleys, in particular to prevent the transmission of oscillations whose spindle length would be given to the distance between this "first pulley" and the second, in the case where the latter would be rigidly linked to the building.

<U> 2. Hot air balloon filling and starting </ U> The "air refueling pipes" described above take advantage of the principle of "solar fireplaces": the hot air rises, then, once they are fully filled, the difference in density resulting, for their entire height of the air column, a pressure difference that creates a call for filling the golf course in a time comparable to that of its rise (of the order one hour), despite the relatively small diameter of these pipes.

The incoming hot air must be able to fill the balloon effortlessly, but also without excessive suction. Insofar as the cables or tractive straps are connected to the top of the balloon, the question arises of the lowering of the lower circular structure during filling. The system of magnetic rods that yield one by one, described in p.11, avoids too fast descent of the lower armature, which would lead the hot air balloon to fill first with cold air which would then be repressed by hot air superior, with a risk of mixing.

In addition, the search for the greater neutrality of the action of gravity again leads to the proposition that the lower reinforcement is, thanks to an important filling in light gases, generally almost as light as air, the same property may even be considered for the lateral envelope of the balloon. These characteristics would also allow these elements to go up effortlessly and thus do not interfere with the emptying of the balloon (from the top and always on the basis of the principle that the warmer air rises) once its rise completed.

3. <U> Analysis </ U> of the rise of <U> balloons </ U> and sizing The density of the air on the ground, for a pressure of one atmosphere and a temperature of 300 K (27 C) is ((29 g / mol) / (22.41 / mol)) # (273I300) = 1.178 kg / m3.

Le calcul théoriquement le plus simple est celui pour lequel à la fois l'atmosphère extérieure, et l'air du ballon, suivent cette équation, ce qui exclut notamment que l'air soit chauffé à l'eau (dans ce cas, l'ordre de grandeur peut être estimé à partir du résultat ci- dessous, en rajoutant les avantages décrits de manière qualitative au point suivant). <I> a) Dry air balloon </ I> The dry adiabatic gradient formula is written as: (1 - 2z / 74) = (p / po) 2/7 = T / To = (p / po) 2 / $ (the coefficients 7/2, 2/7 or 2/5 coming from the fact that the air is considered as a diatomic gas). zo is equal to the ground pressure divided by the ground density and the acceleration of gravity,

The theoretically simplest calculation is that for which both the external atmosphere and the air of the balloon follow this equation, which notably excludes the air being heated with water (in this case, the order of magnitude can be estimated from the result below, adding the qualitatively described advantages to the next point).

For a maximum altitude equal to 2z, / 3, divided into a constant mass half and a constant volume half, we obtain a thermodynamic efficiency of (2I7) # ((1/3) + (19/21) # (1 - (17/19) m)), that is (1,25) / 7, or 17,86%.

Note that this result does not depend on the initial temperature of the indoor air (of course, the economic return depends on it).

In total, for a useful run of about 5760 m in 1 hour (+ 1 or 2 hours for the return and the hot air inflation maneuvers), we have an average speed of 1.6 m / s per balloon (a high climbing speed increases the difficulty of the work and the resistance of the outside air but reduces heat leaks, and increases the power or allows the more frequent use of balloons which can therefore be smaller ...) .

A hot air balloon of 10 hm 'at the start (increasing to 12.84 hm' to 2880 m, then remaining constant) does not seem unrealistic: one year after the first balloon (1783) had been built a 23 000 m ' , which rose by <B> 1000 </ B> m. It is probably possible to gain a factor of 10 in all directions in two centuries. NASA has a stratospheric balloon project (ULDB) of about 60 m radius, nearly 1 hm ("For Science", March 2000, pp. 43 and 29).

The power is thus estimated, for a balloon of 10 hm3 inflated with dry air at 87'C (360'K): the relative decrease in density of the interior with respect to the outside, between 300 and 360 K, is 60/360 = <B> 1/6 </ B>; the density of the air at 300 K being 1.178 kg / m 2, the decrease is <B> 1.178 / 6 </ B> = 0.196 kg / m 2; either for a hot air balloon of 10 hm3: 1960 t, or 19,2 MNewton. The hot air balloon expands to about half of the race, then works at constant volume and accepting air outlets during the second part, which loses 6.25% of the overall theoretical output. For a speed of 1.6 m / s, we therefore have a power of the order of 19.2 = 1.6 = 0.9375 = 28.8 MW (the continuous production of this power assumes that different hot air balloons are relay in such a way that there is always one in traction).

<I> b) Air balloons saturated with water vapor </ I> A constant balloon volume, and regardless of the economic interest in using heat captured or transported by water, The resulting power gains from the use of hot-air balloons with high moisture-laden air are as follows - water vapor is lighter than air (molar mass 18 vs. 29); - arrival at an altitude where the cooling leads to the condensation of water, the hot-air balloon turns into a cloud, but whose air circulation is blocked at the base and at the top (which avoids the formation of too much electrostatic field by friction of the air on the drops of water, and thus the lightning). The motor of these circulations, namely the fact that this condensation releases latent heat of vaporization and that the decrease of the temperature with the altitude is slower than on the curve of the dry diabatic gradient, is thus captured by the balloon . This can then start again, with less gas but a temperature differential compared to the outside stronger; - the fact that the hot air balloon then contains less gas partially solves the problem of the limitation of its volume and the loss of Joules resulting from the premature release of hot air into the atmosphere <B>; </ B> very high saturation in water makes it possible to rain the cloud formed in the balloon. The gravitational potential energy of this rain can also be recovered, by inflating the auxiliary balloons with an additional quantity of hydrogen or helium, whose buoyancy compensates for the weight of the water collected. This compensation plays during the part of the climb that takes place after the condensation, and during the descent, but not during the first part of the climb. On this path, therefore, there is a length equal to the altitude at which the condensation takes place, an ascensional force equal to the weight of this water, and therefore a production of energy equal to its gravitational potential energy. This is actually, after creating artificial wind energy, to do the same in hydroelectric power.

All the above benefits can increase the power that can be produced with a balloon or reduce its size at constant power. On the other hand, to the extent that we are obliged to condense at high altitude water vapor, which will not have been able to transmit its heat to the air (which remains the main driving fluid) from the first moments of operation hot air balloon, the theoretical thermodynamic efficiency is worse than with dry air.

This disadvantage is offset by economic considerations, such as the lower cost of capturing solar energy in solar ponds than in air canopies, or the production of fresh water in addition to power generation. This water (or an additional cargo compensated by light gas balloons), properly cooled during its passage at high altitude, or even transformed into ice, can even supply an air-conditioning network with chilled water, in particular for the engine room, control offices, etc. <U> 4. Hot air balloons return and stowage </ U> Complete deflation of the balloon is from the top (the interior air remains lighter than the outside air), resulting without difficulty in the lower armature and the envelope if they have been lightened air light gases. In the case where the air is humid, the recovery of the water supposes to organize a turbulent mixture between cold outside air and lukewarm and humid interior air. The energy required for the opening and closing operations of the orifices (as well as any defrosting) comes from a few batteries powered by photovoltaic cells.

If the deflated balloon descends under the effect of its own weight, nothing can bring it back to its exact starting point. It must therefore remain a little lighter than air, thanks to a little more hydrogen or hydrogen than is necessary to understand the exact weight of the tare, so that the generator (s) , operating as a motor (at a power 10 or 20 times lower), can pull in the right direction.

For the descent to be done in good conditions, it is necessary that the tension of the cables is even greater than the wind is strong. However, it is not necessary that the excess of light gases be calculated for wind values which are only rarely reached, since it is also possible, in these cases, to obtain a high voltage by not emptying. completely hot air balloon once the climb is over.

The number of cables or straps makes it possible to exert tractions differentiated according to their position with respect to the wind, to place the hot-air balloon as much as possible vertically to the outlet of the hot air. The "refueling pipe in flight" is guided by these cables or straps; for the last meters, a ferromagnetic attraction allows the exact positioning of the ring located at its base, on an equivalent ring located at the top of the outlet mouth of the air.

The descent can be done at a speed greater than the climb (for example thanks to a mechanical speed change, type reverse, between the drums and the DC machine), especially so that no hot air balloon neighbor, while ascending, is at a significant height at the same time as descending, eliminating any risk of scrambling cables even in case of unexpected wind changes. <B> <U> C. Ground Installations </ U> </ B> <U> 1. Transformation of the power of </ U> traction <U> into </ U> power <U> electrical </ U> The balloon transmits its force through cables or straps that must be insulated so as not to play the role of lightning rod; not too heavy so as not to quickly drop the performance of the installation; while operating far enough from their elastic limits so as to remain of approximately constant length; and preferably hydrophobic. The disadvantage of the cables is that they generate a net fold, and therefore significant stress and aging, on the fabric of the balloon, once it is well inflated. These effects can be reduced by replacing such cables with straps (preferably slightly less tight at the edges than at the center). Their disadvantage is to offer a larger surface to aging factors (solar radiation, sand wind, etc.) - correlatively, their shape is less thick so there is less fiber deeply protected from the same bad weather.

Before taking into account the weight of the cables or straps suspended on the balloon, its ascensional force is constant (dry air) or increasing (humid air) as long as it is not at its maximum volume and so it can, in parallel with the decrease in pressure, dilate by keeping a constant amount of air. The force then bends according to the mass of air lost.

One can then wish, or a constant electric power, which requires that the speed increases with the altitude in the second part of the race, a constant speed, the power decreasing then. (In practice, for an optimization with several hot-air balloons operating in parallel, the main phases of different power regimes can be averaged using phase shifts between these balloons, and the speed of each balloon can be approximately constant, allowing the various machines to work, especially in the first half of the climb, in conditions close to the nominal values, however, detailed adjustments of the power can be obtained via the speeds, as described below) .

To these constraints are added those related to the fact that the unwinding of the cable or the strap on a drum is done with a radius that decreases during the climb, further increasing the speed of rotation of the shaft.

All these data, as well as the fact that the same machine must be able to bring back the balloon by fighting against the buoyancy of hydrogen or helium pockets (thus ensuring, thanks to the tension of the cables, a good vertical guidance of the solar chimney), require the use of a DC generator, possibly connected to a DC motor that would (with a centralization of the power of several balloons) an alternator rotation perfectly synchronized to network. The length of the strap or towing cable, from 5 to 6 km, their tension, of the order of 20 MNewton, and their section (identical whether straps or cables) not negligible, require examine their winding on the drum. Its width would be, like its diameter, a few meters, and could coincide with that of the straps.

The question of which axis can withstand such efforts can be resolved by a lack of axis. Assuming that if there were an axis, it would necessarily be my ball bearing (cylindrical) tee, and that these bearings should be the largest possible to resist the forces applied, just give them the size of the drum itself; the axis becomes unnecessary. Only the drum remains, which constitutes a cylindrical rotor evolving inside a stator with which the only contact is constituted by these balls.

One or two toothed wheels also located at the circumference of the drum bases can then transmit the power to one or more smaller toothed wheels, whose axes are shorter, and are therefore not subjected to the stress exerted on the drum itself. -even. The rest of the chain of reduction is not a problem.

The ball bearing contacts are only possible at both ends of the drum, which excludes, for mechanical reasons, the drum is too wide. Its radius can not be gigantic. The winding is therefore necessarily on a large number of layers, and therefore with a non-negligible cumulative thickness, and a fairly variable winding radius, a disadvantage that is added, as we saw on the previous page. , the decrease in strength at the end of the race. Admittedly, the use of a direct current machine makes it possible to compensate for this effect by varying the excitation, but if it is done over too large a range, it is too far away from the nominal operating point.

This problem is thus solved all the more easily as the number of cables or straps is large, an effect that can be taken into account in the determination of the number of spindles of balloons and the number of elements rigid circular structures forming the ridges of the cylinder that will resemble this hot air balloon.

If it is desired to use cables and fewer generators than cables, it will be necessary to be able to mechanically connect the drums while allowing the control of each cable. It will then be necessary for the windings to be done in a perfectly coordinated manner (passage of the layer to the 2nd, the 2nd to the 3rd, etc.). For this purpose, cable imprints may be preformed on the drums.

Servos can control the length of these cables by passing them between the drums and their exit into the atmosphere, by pulleys that we can move: collectively, so as to fight against the wind (and it will be as much easier as the exit points will be further apart); and, individually, the control of the voltage and the length of each cable makes it possible to detect anomalies, with respect to its immediate neighbors (index of a deformation of the envelope of the balloon, due for example to a tear, or of elongation of the cable itself), and with respect to the opposite side (problem of horizontality of the base and the top of the balloon, which can be corrected by differential horizontal tractions on the cables concerned). In the event that the drums are replaced by straps, the pulleys must be adapted to their width and preceded by large funnels.

There does not seem to be any great inconvenience that, during the filling of the hot-air balloon, the drums are mechanically immobilized and not maintained in tension using electric machines. Indeed, when leaving the balloon, its acceleration will be at most equal to that of gravity, multiplied by the relative difference in density (20% maximum), less than 2 mls2.

<U> 2. Overall management of </ U> powers, <U> velocities and cycle times </ U> Most of the technologies used are quite rustic, but modern means must also be used. The balloons must communicate with the base to transmit information on their condition, orientation, wind, etc. They also need to get started and stop emptying at the right time. These communications are by radio, the cables being necessarily electrical insulators.

On a "field" of solar energy production, one can naturally build several hot air balloon piloting bases, to ensure uninterrupted electrical power, and almost constant. The management of this set is naturally intended to be automated, the correction of the hazards resulting from servo mechanisms, and the technical and economic performance of the assembly to be optimized by appropriate computer calculations.

Behind the machines that operate as generators during the rise of bal lons and in motors to make them go down, one places other machines with direct current, functioning in engines, then one or alternators. The fact of having in the electromechanical chain two DC machines allows two adjustments by the excitation of the rotor, so easy control of the balloon rise speed, which can be done completely independently of the electromechanical variables. final alternator.

However, the inertia of the working fluid and the "piston", that is to say, here the contents of the balloon and its envelope, is much larger than for a normal turbine. Since the upward force of the balloon can not be modulated in the short term, the adaptation of the power supplied to an increase in the power demand necessarily involves an increase in its speed. To do this, we must first let the balloon accelerate, that is to say ask him to produce less force, and therefore less power in the immediate future. With a F / m ratio of 1.6 m / sI and a speed of 1.6 m / s, to increase the power by 5% in 1s, it is necessary to agree to produce 5% less force during this time; therefore, to gain 1 MW in 1s, it would have 1.5 MJ in reserve. The most massive power reserves use the irreversible storage of chemical energy. Gas turbines could possibly be used if they are able to accelerate very quickly to adapt to the peak demand. But we can also feed large electrolysers (alumina, molten sodium chloride, water). A withdrawal from this reserve, in the form of a reduction in the continuous intensity dedicated to these electrolysers, makes it possible to immediately supply the transient power necessary for an effective reaction of the hot-air balloon system.

These difficulties only correspond to problems resulting from abrupt variations of the called external power. With regard to the power compensation between different units of the same unit, the control and servo control systems must include anticipation functions of the changes of regime (use of the machines in engines to bring the balloon down; possible tensioning, starting and end of the climb, increasing speed to constant volume, constant volume, and decreasing force).

The adaptation to a peak of power called on a time scale of a few hours and not more than a few seconds can be done by an increase in all speeds and a shortening of all cycles - the system then consumes more than expected ( or stores less) the accumulated heat in the water tanks, waiting for the opposite effect at another time of the day or week.

For more sustainable variations, there is no alternative to using other sources of energy or building additional units.

<B> <U> III. PRODUCTION OF AIR AS MOTOR FLUID </ U> <B> <U> A. Heating of the air in solar windows </ U> </ B> <U> 1. Transformation of </ U> radiative <U> energy into heat </ U> The temperature of 87'C (increase of <B> 60 '</ B> in relation to the ambient temperature) assumed for sizing calculations carried out previously is consistent with the fact that the equilibrium temperature of a black surface with a low re-emission in the infrared (greenhouse effect of a canopy plus possibly adequate surface treatment) can reach 200 C .

The principle sought is the use of the least sophisticated materials and therefore the cheapest possible: metal canopy on standard foundations, "radiators" in the electrotechnical sense of the term, heat storage tanks for 24-hour operation, filled with water or consisting of rocks, air intake with simple dust collectors, etc. Large fans can be avoided if the air is sucked in at the entrance of the hot-air balloon by the "solar chimney" effect (hot air rises), which results either from the textile cylinder "in-flight refueling". (page 14), or the construction of a solar chimney built in the center of the canopy.

The increase of the air temperature and therefore of the efficiency can be done: by using double glazing (which has the disadvantage of increasing the losses by reflection) by fighting against these losses by using inclined panes (fixed ) or orientable (movable) towards the south (for the northern hemisphere), and / or orientable with respect to the east-west direction, and / or anti-reflective treated on one or more of their surfaces; by improving the non-reissue in the infrared of the sensors; using thicker glass, for the purpose of better thermal insulation, than is strictly necessary from a mechanical point of view.

These improvements will be more useful if the air joins the hot-air balloon in two stages, preheating in a normal canopy, then a second heating, with a higher equilibrium temperature, in an improved canopy.

Moreover, if the cost (investment depreciation and operating cost combined) of glass roofs was significant compared to that of hot air balloons, it is possible to avoid releases into the ambient air of already heated air (inevitable , because of the dilation of the air, in a system with a single balloon), by arranging so that there is always or nearly always a balloon in which this excess air can be discharged resulting from the dilation .

This is possible by installing two or three hot-air balloons on the same heated glass roof, so that the duration of a rise coincides with the heating of a layer of air. Although the rapid descent allows to avoid that there are two balloons at the same time at altitudes higher than about 2000 m, one can, to remove any risk that their cables become entangled, do not use a canopy of massive form but build it into two or three units connected by one or three large corridors (also heat sensors so that their cost is not an additional unproductive cost) allowing air currents equalizing pressures.

We will see in the following point that such a more frequent use of the hot air produced by the canopy also reduces its volume, ie the "ceiling height", which can also be generating savings.

If it is accompanied by a great reduction of costs, a moderately efficient pre-heating can be admitted. This consists in replacing the windows by simple nets, much lighter, but able to fulfill almost the role of obstacle to the escape of hot air upwards. To do this, it would be necessary that the air is guided, and maintained in slight underpressure with respect to the atmosphere, since its entry in the system and until final windows (or the evaporator of water - Cf. part For this reason, the corresponding claim is placed in position 40), by large and slow fans, which would probably take a negligible power on the production of the balloon.

The heat exchange with the black panels (slightly raised and raised to avoid sanding) located on the ground would also be improved by these fans, to the extent that, all turning in the same direction, they would give the current lines a helical shape allowing to vary the parts of the flow in contact with these black bodies. However, one can also consider other configurations. For example, each row of fans could only include one in two. The next row would be shifted transversely across the width of a fan, filling the gaps in the previous row. Nothing would oppose in this case that the direction of rotation of the blades is reversed from one row to another.

The disadvantage of this solution is of course that one loses the greenhouse effect related to the windows (conversely, one avoids the losses by reflection, and the transmission factor of a net can be compared advantageously with that of 'a glass or double glazing).

This greenhouse effect is based on the absorption by the glass of infrared radiation emitted by heated black bodies. The question then arises of the future of this heat captured in the glass, and of its transfer by conduction to the surrounding air masses. In double glazing, the lower glass gives way (upward) its energy to an air space thin enough not to convect. On the other hand, the conduction is not stopped. Another option is to place this lower window halfway up the canopy. The heat given off by this glass is then transferred to air which, admittedly, convects a little, but can however be poured into the balloon. Mixing this less hot air with the lower warmer air is not aberrant because the thermodynamic efficiency does not depend on the increase in air temperature (open cycle), only the limitation of the volume of the hot air balloons imposes the use of air that is not too warm.

For a system with two or three interconnected canopies, and as many hot-air balloon flight devices, the air inlet side airlock and the air circulations within the canopy can be adjustable, so as to slow down the arrivals of the nearest unit, and to accelerate those of the most distant arrivals, so that each hot-air balloon, whatever its place of departure, fills with almost all the air of the canopy.

<U> 2. </ U> Dimensioning <U> and the interest of connecting together several glass roofs </ U> The glass roof area necessary to allow a hot-air balloon to operate can be considered as: the power received, perpendicularly, with a good sunshine, can be taken equal to 0.9 kW / M2. On average over 12 hours, taking into account the inclination of the sun, it remains 0.4 kW / M2; over 24 h: 0.2 kW / m2. If one estimates at 50% all the thermal losses (reflection at the entrance, reissue in the infrared, conduction of the glass or thermal insulators placed under the glass roof, etc.), it remains 0,1 kW / m2, or 100 MW / kmz. The thermodynamic efficiency of hot air balloons amounting to z ,, / 3 with a constant mass then at 2z ,, / 3 with a constant volume, being 17.86%, the mechanical power obtained is 17.86 MWIkm2. The power envisaged above (28.8 MW divided by two if we assume that we have a single balloon per canopy and that it only works every other hour) with a speed of 1.6 m / s requires therefore a sensor area of 14.4 / 17.86 = 0.81 km2 (figure to be increased slightly in the case where a part of the heated air is released into the atmosphere which, because of the expansion, can not stay in the glass as long as the balloon has not been put back in place to recover).

Like the 100 MW / km2, the 14.4 MW power is a 24-hour average. As the power demand is lower at night, values of 16.8 MW and 12 MW can be achieved with temperature differences from outside of 70 and 50 (actual air temperatures of over 110 and under 60, because it is cold at night in the deserts). For differences between the night and day powers even greater, it will increase the speed of hot air balloons during the day and decrease at night.

The thickness of the air layer which can be heated from 27 to 87 C in a period of hours is determined by means of the heat capacity at constant pressure: CP = 7/2 nR; Cp / n = 7/2 R = 7/2 # 8.32 J / .mol = 29.12 J / ml. To reduce to a m3 at 27 C, divide by (22.4 # 300/273) = 24.6 <B> 1, which is: 29.12 J / = 24.6 1 = 1.183 kJ / .M3. Knowing the power received already calculated above: 0.1 kW / m2 on average over 24 hours, as well as the duration of a heating (equal to twice that of an ascent): d hours, we receive, per m2 , average energy <B>: </ B> d # 3600 s - 0.1 kW = d - 360 kJ / m2. To increase the temperature of the ambient air by 60, its thickness must be e = d # 360 J / m2 / <B> (601 </ B> # 1,183,103 J / .m3) = d # 6 / 1.183 = 5.1 d, in meters.

This is the thickness of air at 27 C (V ,,, = 24.61). If we want to check that the volume of the balloon at the start is 10 hm ', we must take into account the expansion, then it starts with air at 87, and we have a volume of: 0.81 km2 # (360/300) # 5.1d = 5 d, the unit being km2.m, that is, hm3. With d = 2, we find 10 hm3.

The formula e = 5.1d shows that it is necessary to arbitrate between the climb speed (too fast, it makes the mechanical control more difficult) and the thickness of the canopy. Reasonable values appear: 10 m high, for d = 2, ie 1 h of climb (hence the average speed of 1.6 m / s, or 5.76 km / h), as much for the descent, the stowage, reinflation.

We can also eliminate the coefficient 2 which affects the duration of rise, by installing, on the same heated glass roof (of form described above), two or three hot-air balloons taking turns so that the duration of a rise coincides with the heating a layer of air. We can then have, at the same time, a canopy height limited to 5 m and a speed of 1.6 m / s (the power is then 28.8 MW and the surface of 1.62 km2), or 10 m and 0.8 mis (power remains 14.4 MW and area 0.81 km2), or any canopy height and velocity values with a product value of 8, power and surface area varying as long as A temperature difference of 60 and a starting volume of the hot air balloons of 10 h are maintained in proportion to the speed.

It is also known <B> (CE </ B> supra) that this variant avoids the escape of air as it expands, because, with a single space and three balloons, there is always has one on the ground that one can begin to inflate, under the sole effect of the dilation (before finishing the inflation with all the air present in the canopy, by replacing it with fresh air).

The calculations above assume, as we saw in verification, that we empty all the air of the canopy at one time in the balloon, which allows to limit the height of canopy. However, near the hot-air balloon launching devices, or in the corridors connecting several units within the same canopy, it is preferable to have greater heights, because the moving airflow concentrates on a single space. Weaker width. It is therefore possible to have an air volume of the canopy slightly greater than that of the balloon; the air already heated but in surplus will remain "on the platform", in these same areas located near the outlet mouth or in the corridors connecting several units.

As discussed above, it would be very appropriate to have in these places windows of better thermal quality. However, the optimum canopy height is precisely proportional to the amount of heat per m2 captured by the system. Everything is therefore combined favorably since, starting from the idea that in these places a higher height would be necessary, we find the same conclusion at the end.

<U> 3. Storage of heat and thermal insulation of the soil </ U> The storage of heat is necessary for the continuity of the electricity production and the satisfaction of the daytime needs <I> I </ I> nocturnal and in sunny weather < I> I </ I> covered. Although not the only one possible, storage in the soil is an interesting option. The question arises, however, whether the thermal conductivity of the soil is sufficient. However, to obtain the best performance, one is also led to ask the opposite question is this conductivity not too strong and will not we have significant thermal losses from below? In reality, the surfaces of the canopies (NB - not that of the connecting corridors between different units of the same canopy) is such that, up to several tens of meters, the warming of the soil by conduction does not result in a leak towards the outside environment. It must therefore be considered as a very long-term heat storage (ultimately balanced by the geothermal heat flux), and not as a loss. It will therefore be more economical not to provide horizontal insulation under the canopy, but at most a circular insulating skirt at its perimeter, about ten meters down, stopping lateral leaks. <B> B. </ B> <U> Spray </ U> <B> water </ B> <U> moderately </ U> <B> hot in the air </ B> the use of moist air as a working fluid has been demonstrated in point b) of Il - B - 3 (sizing), p. 16. At first, this generates a gain due to the lower density of water vapor compared to air. Then, at an altitude where the cooling leads the water to condense, the balloon becomes a cloud. The latent heat of vaporization released by the condensation causes the decrease in the internal temperature of the balloon to be slower than that of the external air, which allows the temperature differential to increase. The cloud formed in the hot-air balloon can finally rain, which can fulfill a function of desalination of seawater, and, moreover, the gravitational potential energy of this rain can be recovered.

This moist air is obtained by performing a "shower" of hot water (either by dropping it from a surface pierced with small holes, without having to pressurize it, or by creating fine jets of water, directed upwards, obliquely or laterally, which are divided into droplets.

<U> 1. Use of Solar Pools </ U> Subject to the alternative energy sources proposed in the next point, the use of solar pools is a natural way of producing the hot water required by the production of hot moist air (and associate the power generation function with the seawater desalination function).

Indeed, the production of hot salt water at low prices is the characteristic of solar basins. The layer of water to be heated, of high salinity, is at the bottom of a basin; it is thermally insulated from the atmosphere by other layers, including, on the surface, a layer of cold water, which loses little heat by evaporation, and low salt, all being stable relative to gravity, and therefore anticonvective The layer of ground water also plays the role of heat accumulator.

However, here, the structure of the different layers of water must be considered dynamically and no longer static. The heat of the hot water from the bottom of the pond is not collected through a heat exchanger, it is this water that is collected to be vaporized in the air feeding hot air balloons.

In basic design, it is returned to its starting point, colder but also in smaller quantities (a part evaporated in the engine air) and even more salty. The total amount of water and salt in the basin is conserved by the fact that some of this very salty water is also returned to the sea or salt marshes, while cold sea water, same salinity as the upper layer of the basin, is poured there. This creates a slight flow of water from top to bottom, with two beneficial consequences. In the first place, there is no need to worry about salt diffusion from the bottom up, and the difference in salinity (hence the stability of the layered structure) is maintained.

In the second place, the heat of the intermediate layers, resulting from the absorption of the solar rays and the conduction from the black body, is slowly returned downwards. It is thus better valued. In addition, the surface layer no longer plays the role of cold source, and therefore yields little heat and water vapor to the atmosphere, thus avoiding the difference in density and temperature gradient between the interior and the outside of the balloon is reduced.

The hot water is harvested using large pipes drilled, rolling on the bottom of the water on solid tracks (if this condition was not feasible, we could equip these pipes with ballasts to ensure they almost waterline). The pipes sweep angular sectors so as to ensure in good conditions, at the center of rotation, the evacuation of the water. If the drive is from the shore, it should be simple angular sectors, with empty return to the starting point (so it takes several sectors to feed the same evaporator). (It is also possible to envisage a permanent circular movement, like the basins of sewage treatment plants, but the question of driving the pipe is more delicate). Arrivals of water are made in the wake. The basic design described above therefore requires three parallel pipes, in a triangle, the return of very salty and warm water being just behind the hot water harvest, with the supply of fresh sea water to the surface.

However, this design is optimal only in case of high salt diffusion from bottom to top (in principle, the layered structure of different salinities blocks all convection), which is not certain to happen spontaneously. Otherwise, the lower layer will increase in salinity to a very high value, which is not conducive to evaporation and desalination. It may therefore be advisable to mix this return water with initial sea water, so that its salt content is only slightly higher than that of the hot water taken. However, in the case of a relatively high temperature solar pond, this leads to reinjecting cold enough water exactly where, an hour later, we will again want to take hot water.

It would therefore be preferable to reinject water halfway up, so that the bottom layer is replaced by that which was immediately higher, already hot enough. However, if the principle of maintaining the total amount of salt (and water) in the basin is scrupulously respected, the salinity of the layer thus reinjected at mid-height will be at least equal to that of the layer taken from the bottom. and so she will fall to the bottom too.

But the same principle may suffer momentary exceptions, provided that on average over 24 hours (or more), the quantities of salt and water taken and reinjected are equal. Thus, at certain time slots where it is necessary to preserve the heat of the lower layer and immediately adjacent layers, it will reinject in a middle layer of return water sufficiently mixed with low-salt water, so that its den - it allows him not to fall to the bottom. And at other times, very salty water will be reinjected, homogenizing all the lower layers, so as to reconstitute the normal salinity gradient without the lower layer being excessively salty.

The determination of the optimal hours for these two behaviors can depend on the sunshine, the electricity needs of the network, the fact that hot air balloons are more effective at night because the outside air is colder and therefore heavier.

You can also alternate the roles of several basins. One will produce very hot water, used for the last heating of the air, while the other will be satisfied to give the moderately warm water, serving for the first heating, until one exchanges these roles to restore the average characteristics (total amounts of water and salt) of each of them.

A variant of the same principle consists in using a preheating basin whose water feeds, by the bottom, the basin at high temperature, the water of the latter being first used to heat already preheated air, then, having thus lost part of its heat, to preheat cold and dry air. (This diagram is thermodynamically equivalent to the principle described in the previous paragraph, it has the advantage of reducing water transfer between solar pools and evaporation showers, replacing them with basin-to-basin and shower shower transfers) .

Moreover, the thermodynamic efficiency enhancement of the solar basin can possibly be sought using the same tools as for the glass roofs: oblique orientation of the surface that can result from the existence of waves propagating on the surface; additional layer of thermal insulation, antireflection and / or anti-evaporation. This last point must also be considered in that the performance of the balloon itself is better in a dry atmosphere.

<U> 2. Other possible sources of hot water </ U> As mentioned in the introduction, it is possible to contribute to the fight against the greenhouse effect by developing solar energy, but also by improving the energy efficiency of production methods. existing electricity plants (thermal or nuclear power stations), or by using other forms of renewable energy such as geothermal energy in electrical form.

This last point joins the logic of the invention of proposing an income of substitution to the current producing countries of hydrocarbons, the geothermal energy being able to come from old wells of oil, today exhausted, where one would inject cold water to extract it later, warmer. More generally, any abundant source of low temperature heat which has water for coolant and which does not find a suitable utility in the form of heating homes or greenhouses, industrial processes, etc., can be valued in the context of the present invention.

In particular, the low temperature heat produced by large thermal or nuclear power plants can supply either the "air plants" described in the following point, or balloons, or both.

A good efficiency of these secondary stages of electricity production can pass through a slight decrease in efficiency of the primary stage or by additional investments in thermal contacts, so that the water leaving the exchangers that cool the steam turbines are a little cooler than in these facilities as they are now designed. However, the present invention can also help to meet the constraints of low environmental disturbance (especially when it comes to rivers) sampling (improvement of the percentage of water returned) or rejection (good cooling water rejected ). It is therefore not excluded to operate the air plant and / or hot air balloons from not too cold water without generally affecting the proper functioning of the plant, whose cooling system characteristics are not only the result of the desire to have a heat exchange cold source at the lowest possible temperature.

With regard to the use of the "air plants" described in the following point, not in the countries envisaged above, but in the industrialized countries, their supply of very cold air will be possible, even during the day, during the waves. cold where the demand for electricity is the strongest. It is therefore not necessary to provide the important means of storing cold air developed below.

In the case of nuclear power plants, balloons can be developed autonomously, as previously described; However, we can also consider turning into "solar fireplaces", replacing the refueling pipes in flight, the cooling towers that already provide, in fact, the function of creating artificial cumulus, without recovering the upward force.

 3. Improvement of <U> Efficiency by Constant Water Spray </ U> The most promising features of the invention, as they result from the above description, are as follows: hot water, possibly salted, available at a temperature of the order of 60 to 100 C, for a moderate cost; evaporation of this water, in the form of "showers", for heating and saturating in water vapor large amounts of air, intended to serve as a driving fluid; very limited cooling of this air during its relaxation, due to the presence of water vapor, whose con densation provides the heat necessary for this quasi-maintenance of its temperature; use of this air saturated with water vapor, in a balloon whose operation is comparable to that of an artificial cumulus, so as to capture, primarily, the ascensional force, and as an accessory, fresh water obtained by condensation of steam, the same characteristics of using water as heat transfer fluid and air saturated with water vapor as the driving fluid, without turbine, using large devices (particularly large gas envelopes), operating in coastal deserts, under fairly low pressure, at limited speeds, from a hot source of relatively low temperature, but using a cooler colder than is usually the case , and finally producing a large power and possibly fresh water in a significant amount, are found in the device described below.

Although using the same principles as hot air balloons, it is not a competitor, but complementary. In fact, the air is made to work between 1.4 atm and 1 atm. The proud Montgol, she makes it work between 1 atm and 0.5 atm. One can thus recover the air at the exit of a system to use it in the other one. This is all the more justified because, if we try to work at temperatures that are not too low (so with a relatively high saturation vapor pressure), neither of these two systems consumes all the heat with good thermodynamic reactivity. latent vaporization of water from solar pools. By cons, using them successively, it is better valued. In addition, the existence of a plant operating entirely on the ground guarantees the continuity of at least part of the electricity production, even in very high wind. The power produced by this "air factory" being, for the same moist airflow, of the order of a third of hot air balloons, for an industrialization that seems of the same order of difficulty and cost, it is a priori an accessory element to be included in the hot air balloon system. However, due in particular to its previous position in the humid air chain, and perhaps less innovative materials to implement, it can not be excluded that such a plant (reduced prototype or real size building) be built before hot air balloons. This is why the protection claimed by this patent covers this plant as well, insofar as it would be integrated into the humid air chain that leads to hot air balloons, or that it would be autonomous and free in the air. atmosphere the humid air expelled by the "exhaust" phase.

<I> a) Principle of the "air plant" </ I> Air is either ambient or preferably colder (see infra, point f), is transferred, approximately every minute, by tens of thousands of m ', in premises capable of withstanding pressure differences of the order of 1/2 atmosphere and equipped with a large piston (several hundred m2) at each of their two ends.

One of these pistons, which will have to work only under limited pressure differences, and which can therefore be moved by an ordinary process (pneumatic or hydraulic cylinders, sealing provided by bellows) allows admission and exhaust of the driving fluid. The latter (air initially ambient or cold) can be pre-compressed by the return of the engine piston, then is heated as at the beginning of point B above (hot water showers). For cold but non-pre-compressed air, its temperature passes approximately 0 C to 60 C, resulting in an increase in air pressure of more than 0.2 atmosphere, to which is added the vapor pressure saturating water (0.1 to 0.2 atm).

This air can then relax, in a big fraction of a minute, by pushing the other piston with a force measuring 107 N on a run of a few tens of meters. We find a power of the order of one to several tens of MW. (This recipe is the only one of its kind, the production of fresh water depends on whether the condensation occurs in the form of drops large enough to fall immediately on the ground and remix with the salt water of the heating, or if these drops remain in water. suspension and can be collected on filters during the exhaust phase).

This power is continuously produced when there are several "cylinders" so equipped with pistons, and who work in turn. It is even possible to co-ordinate these cylinders and to collect these powers in a manner similar to that which is employed for two- or four-stroke combustion engines ("combustion engines"): finally, a single circular motion is obtained. approximately uniform, regularly driving a single electrical generator (or three machines: DC generator, DC motor, alternator, if you want optimal power supply network).

The reciprocating movement of the piston can be broken down into three main phases for about a quarter of a cycle, the expansion of the gas pushes the piston which drives the rest of the transmission chain to the electric generator; during the following quarter, the return of the connecting rod and therefore of the piston allows the complete exhaust phases of the air (the rear piston coming to meet the engine piston) and cold air intake (the engine piston recedes , but the rear piston moves back even faster - the succession of these phases being fast, one can even predict that, rather than being braked and then set in motion in opposite direction, the rear piston "bounces" on the engine piston which would be equipped with fairly flexible springs).

 Finally, it seems necessary to obtain a fairly good stabilization of the piston during half of the cycle. Indeed, the yield is optimal if the vaporization of the water is done in a not too small duration (at least a minute) and with a rather stable volume (one can however use the piston to compress the air before heating it and vaporize the water, as will be seen later, and these two phases may slightly interpenetrate, it is also useful to start the expansion of the gas a little before the end of heating, so as to clipping the curve of pressure, and thus reduce the pressure resistance specifications, which are a significant cost factor).

To obtain this stabilization of each piston during about half of its cycle, while transforming its cycle into rotational movement and its motive force in engine torque as constant as possible once the contributions of the different "cylinders" have been added, it is necessary to to adapt the principle crank-handle. Three solutions are presented in the following three points.

 (A last homogenization can come from the use of flywheels, which will have to be capable of supplying or absorbing from 10 to 100 MJ without significant variations in their rotational speed - a kinetic energy of 1000 MJ corresponds by example at 40 tons distributed at 7 m from an axis turning at S revolutions / s, or at 110 tons at 3 rev / s. From this point of view, it is a good complementarity with the speed and speed control. hot air ballooning: at time scales of less than one second, the power required on the flywheels, and not on the electrolyzers envisaged on page 19-20, can be used to relieve the hot-air balloon and enable it to accelerate; a few seconds to a few tens of seconds, it is the opposite of the acceleration of the balloon that relieves the air plant and allows it to restock kinetic energy rotation, beyond the minute, a reinforcement of the flow of ch from the solar basins both increases the electric power of the air plant, and the flow of moist air produced by the latter, which must stabilize at a higher level if hot air balloons are to continue to turn faster with unchanged volume).

<I> b) First variant of the crank-handle principle: crank with groove </ I> The first solution is to use as a crank a disc (in the practically hollowed out practice) equipped with a groove going from the center to a crank point close to the periphery (Figure 2). The end of the connecting rod is housed in this groove; during a half-turn, it remains in the center of the disc: this allows the piston to stabilize during half of the cycle, which was sought; for a quarter turn, the expansion of the gas pushes the connecting rod which drives the disc; and during the last quarter, the return of the connecting rod and therefore the piston allows the exhaust and intake phases.

The disadvantages of this solution are that it is the radius of the disc which is equal to the stroke of the piston (so its diameter is equal to twice), and that the trajectory of the different connecting rods prevents these discs are mechanically secured by a fixed link .

They can however be coaxial (around a vertical axis) and rotate at the same speed. They are supported, held in place (according to the principle described in point II - C - 1, page 19, holding the winding drums of the cables or straps of balloons) and secured by their circumferences, which are equipped with except for the underside of the lower disk and the upper surface of the upper disk, toothed tracks slightly discharged to the outside. Gear wheels whose horizontal axes are integral with the frame, constitute with these tracks conical gears, and thus ensure both homo généisation movements (rotation speeds will be strictly equal, although in the opposite direction of a disk) and, for one of them, the transmission of the neck (reduced since the speed of rotation will be amplified) to a horizontal shaft which feeds itself, after one or more other stages of gearing, the electric generator (alternator or DC machine). A disc may have two grooves, one on its underside and one on its upper face. In total, one can for example have four disks, and therefore eight pistons, two of which work at the same time, one at the beginning of its relaxation, and the other at the end, so with a lower force. The number of eight pistons thus allows a certain smoothing of the transmitted power, which can be further improved by adapting the shape of the grooves to the evolution of the force produced (they have not been represented in rectilinear form, in the figure 2, that for the sake of simplification - moreover, they may be equipped with springs, so as to prevent the crank from passing abruptly from one end to the other of this groove).

<I> c) Second variant of the crank-rod principle: use of engrena - </ I> <I> non-circular grids </ I> The second solution consists, once the reciprocating movement of the rod converts in circular motion crank, to use non-circular gears, or circular but eccentric. It is thus possible to widen, in the curve giving the abscissa of the udder as a function of time (before this transformation, this curve is approximately a sinusoid), the minimum abscissa level.

A typical example of non-circular gears is a pair of identical ellipses, each rotating around its focus, which are separated by a distance equal to the major axis of the ellipses. This geometry is quite suitable here (see Fig. 3), although it is possible to slightly modify these contours so as to obtain the best smoothing, on a cycle, of the balance on the cylinder and pistons. between the power produced and the power consumed. Moreover, by varying the eccentricity of the basic ellipses, one can choose the number of cylinders, connecting rods and gear pairs, while maintaining this objective of smoothing the power.

The main problem is as follows: whatever the mechanical variant proposed, as soon as the thrust phase of the piston succeeds that which one wanted to widen (quasi-immobility allowing the vaporization of the hot water), this phase piston thrust (for which the two ellipses are contiguous by their long sides) leads to a traction of one ellipse by the other, and not to a thrust (there is naturally rolling of one on the other but the non-circularity of the gears makes the force not only have a tangential component, here the normal component tends to separate the gears and not to join them).

It is therefore necessary to create a bilateral mobile link. This will take the form of a small trolley with horizontal wheels (Fig. 4), forming two or three pairs of pincers between which they will be clasped from the vertical running tracks inside each toothed ellipse. The robustness of this truck and its wheels must be such that it transmits a large part of the total thrust of the piston (its normal component). It is excluded that its bearing can result from the simple advance of the contact points of the two ellipses: the fact that in the rear, they tend to deviate, can very easily be transformed into forward motion of the cart. It will therefore be motorized, and enslaved to follow the movement of this point of contact (the simplest being a servo controlled by the difference in spacing between the pair of front wheels and the pair of rear wheels).

The diameter of the circle described by the crank is equal to the stroke of the piston, so its radius is equal to half of this stroke. The gears are in horizontal position, the "cylinders" are distributed around a vertical central axis, to which are fixed, one above the other, all the follower gears of each pair (the cohesion of this set may result not only the attachment of each gear to a cylindrical shaft, but also direct links, thus benefiting from a greater lever, a gear to the next). The movement can then be scaled down and transferred to horizontal axis electrical machines using conventional gears.

<I> d) </ I> Third <I> variant of the crank-rod principle: </ I> alternative <I> connection </ I> <I> of the two-piston </ I> piston rod <I> phase opposition </ I> The same purpose (to obtain the immobility of the engine piston during the fraction of the cycle about its half - during which the cold air is heated and saturated with water vapor by the hot water of the "showers" ") can optionally be achieved by a third variant: two neighboring" cylinders "operate with a phase shift of half a cycle, so that the same rod is connected half the time to the piston of one of these cylinders and the the other half to the piston of the other cylinder. This connecting rod therefore has a quite classical movement and leads to no particular characteristics other than large dimensions (here we find here an articulation that describes a circle whose diameter, and not the radius, is equal to the piston stroke) of the system, a "normal" crank.

In particular, unlike the first variant, it is possible to have a single solid playing the role of all cranks: it can be a large crankshaft, in the case where the different "cylinders" are arranged side by side on both sides of a horizontal axis, or a single vertical axis with cylinders arranged in a circle around the disk which carries this collective crank eccentrically (in the latter case, the two cylinders in opposition of phase should preferably be located one above the other).

The difficulty of this technical solution lies in the fact that it is not enough to uncouple a piston from the connecting rod at the moment when the other is coupled; it is necessary, perfectly synchronized, lock the piston that is uncoupled and unlock the one that is coupled, which requires a control system (for example pneumatic) sufficiently branched, powerful, fast and reliable.

<I> e) Fourth variant of the </ I> principle <I> crank-rod: use of </ I> <I> quasi-epicyclic movements </ I> The aim is simply that the piston remains almost immobile during the heating phase of the air, it is not absolutely necessary that the rod is deprived of all its degrees of freedom. It can therefore describe a circle around its point of attachment to the piston (with the particularity that the concavity of this circle is on the outside of the entire trajectory of the connecting rod-crank).

Such a shape corresponds to that of an epicycloid (movement of a point of a circle that rolls without sliding inside a fixed circle - <B> CE </ B> Fig. 5). This must be three points, so that one side corresponds to the heating, one to the relaxation, and one to the phases under atmospheric pressure (exhaust - admission). A symmetry of order three is obtained if the inner circle has a circumference, thus a radius, three times smaller than the fixed outer circle.

The point of this inner circle which describes the epicycloid plays the role of crank. It is possible to add an adjustment variable by admitting that the crank-crank joint is situated at a distance r from the axis of the crank, distinct from the radius r of the rolling circle (in any case, this articulation necessarily having a certain volume, it must necessarily be at a different level from that of this circle - see Fig. 6).

We can then look for an optimum. Theoretically, the result to be achieved is a radius of curvature of the trajectory almost constant around each passage closest to the center. It is obtained for a value of r, equal to 0.8 r. However, this leads to a connecting rod length equal to 10.8 r (ie 1.8 times the diameter of the fixed outer circle).

However, wide variations are possible without greatly degrading the quality of this optimum. Thus, a length of connecting rod (this is the distance between the axis of the crank and the articulation with the piston) equal to 1.05 times the diameter of the outer circle, which is optimal in terms of size , combined with a radius r, equal to 1.06 r, certainly generate small oscillations of the position of the piston during heating, but these remain less than 1% of its stroke, which is quite acceptable. Fig. 5 corresponds to this solution.

The symmetry of order three allows to associate any number of cylinders, as long as it is a multiple of three (in practice, it will be 3, 6 or 9). Each group of three cylinders, distributed at 120 and out of phase by a third of period, has its three connecting rods connected to a single crank. One (for 3 connecting rods), two (for 6) or three (for 9) cranks are joined in a vertical crankshaft. Viewed from above, on the circle of radius r ,, whose center itself describes a circle of radius 2 r, they are distributed at 180 or 120 (see Fig. 7).

The usefulness of having two or three sets of three cylinders and three connecting rods results from the fact that, during the not insignificant time interval spent near a point of the epicycloid (a fortiori if it has been transformed into a loop with r, greater than r), none of the three cylinders works (this results from the fact that the period of quasi-immobilization of the piston is, thanks to these small loops, of the order of half a cycle, which is in itself a good thing, however, the period of thrust being only equal to half of the rest, we see that three times a quarter is not 100%). Only the work of one of the cylinders or other games ensures the continuity of the driving force (which does not dispense with having a flywheel as powerful as for the previous variants).

On the other hand, the disadvantage <B> (CE </ B> Fig. 7) is that the rolls are much narrower than wide, which is not optimal in terms of pressure-resistant material surface, for a given volume.

Fig. 6 describes the concrete realization of this principle. It can be seen that there is a second gear wheel of radius r, in the center of the system. Its function is threefold - by turning on itself without translating, it forces the gear of the crankshaft to remain in a crown r rr inner r and outer 3r, which ensures the maintenance of contact with the outer circle, and therefore the quasi-epicyclic trajectory of the crank-rod joints - always because it turns on itself without translating, unlike the crankshaft, it allows to collect the movement and transmit it to a horizontal shaft; - Finally, it rotates twice as fast as the crankshaft, whose rotational movement (distinct from its translation on a circular path) was already twice as fast as the movement of the crank-link joint, itself of equal period at the cycle heating- relaxation - exhaust - admission. It has thus taken a lead of a factor 4 on the subsequent gear ratios (an even higher ratio could be obtained by using two different gears for the crankshaft: one of radius r for the internal contact with the fixed circle of radius 3r, and one of radius between r and 2r, for transmission to a central gear, however, it is not certain that this solution has more advantages than disadvantages).

 The cylinders (pistons side) always being filled with air at a pressure equal to or greater than that of the ambient air, the thrusts are always exerted towards the center of the device. This has two consequences, which are solved by a single solution <B> (CE </ B> Fig. 6).

On the one hand, the frames of these cylinders are subject to these important tensions, and it is useful to reinforce them, inter alia, by connecting the lintels of their front faces, which form a triangle, a hexagon or an enneagon. Achieving better rigidity for this assembly requires the realization of a lattice on its entire surface, which therefore constitutes a ceiling for the device described above.

On the other hand, the crankshaft is, in its upper part, subjected to horizontal forces whose resultant is directed towards the center of the device, which unbalances it and exerts a push on the central part. In order to avoid further strengthening this piece to stiffen it, at great price (as the crankshaft itself), we can extend the latter upwards, and finish with a pin found the axis of the crankshaft, this which ensures a circular translational movement of radius 2r, and therefore the possibility of leaning on a track made in the ceiling defined above, by means of a wheel mounted (with respect to this pin, him- even in rotation) on rolling, and rolling without slipping on the track in the ceiling.

This solution may possibly have the consequence of making superfluous the other adaptations shown in FIG. 6 and intended to reduce the fatigue of the central structure and the gears: and the fact of using two levels of non-slip contact, one or both being equipped with gear wheels; and the fact of adding another cylinder symmetrical to the one carrying the crankshaft, but being devoid of crank itself (one could imagine that each of these cylinders carries a crank, for example to better distribute the forces, however, the axis of the crank linked to the upper link set would be swept by the lower links The solution proposed in Fig. 6 results from the fact that, as for the solution of the firing by the propeller center for the old fighter planes, the only zone which is not swept by the connecting rods and which can thus ensure the connection with the next game, is that which is inside the crank).

The same solution would be possible at the base of the crankshaft, provided that the problem of thrust towards the center arises with the same acuity, which does not seem to be the case considering the distance of the cranks and the number of contacts already existing. It is therefore not implemented in FIG. 6.

The rigidity of the crankshaft itself is obtained thanks to a large widening of the cranks, in particular the lower one. Although this may lead to the fact that they overflow from the rest of the mechanical power collection device, there is no congestion problem as long as their radius remains below 1.5 r because they are falling back (circle greyed out in Fig. 7, which, like Fig. 6, corresponds to the most unfavorable case) where the piston has actually retracted to return to its most recessed position, and because the "cusp" shape of the epicycloids allows them to exit where they entered without moving transversely, thus respecting the guiding structures of the pistons.

For the different bearings, there are conventionally two options: either the balls or rollers directly contact the two parts to be connected, with the disadvantage that they are not fixed with respect to any of these two parts and that it is therefore necessary a complete circle, the same balls or rollers are mounted on an axis itself linked to one of the two parts by a smaller ball bearing.

In both cases, it appears difficult to ensure a direct contact (using a single bearing) between the frame and the base of the crankshaft, whose trajectory is epicyclic. This movement being the composition of two rotational movements, the solution is to interpose a piece having only one of these movements. This piece is the flat elliptical ring of fig. 6, clearly visible in the view from above, and which is well in rotation of period T with respect to the frame, the crankshaft being rotated by period T / 2 with respect thereto (this ring also provides additional guiding of the base crankshaft, guaranteed that its axis describes the circle of radius 2r).

* Finally, we note (in Fig. 7, for example) that the three connecting rods of the same crank always make it at least an angle of 90 between them. The transmission of the thrust is thus not limited to a thin horizontal crown, as one might think from fig. 6, but can be exercised, in the limit of 90, on a higher height, which is mechanically preferable. Only a thin crown makes the complete turn of the crank, which is not a problem since, the cylinder being always at least at atmospheric pressure, the rod never works in tension.

<I> Adaptation of the rotary piston engine </ I> It is also possible to draw inspiration from the rotary piston engine and no longer from the conventional two- or four-stroke engine, which makes it possible to dispense with the crank-rod system. .

The rotor comprises a number NI of pistons <B> (Ni </ B> = 10 in FIG. 8) which, as in a vane pump, are subjected to a force (preferably of pneumatic origin) directed towards the outside, which plates them permanently against the wall of the stator. The latter has a non-circular section, the profile of which can be quite freely chosen, in particular to satisfy the same criteria as before (to obtain a roughly constant torque and to leave a long enough time for heating the air by volume almost constant).

This profile can have a symmetry of order N2 (N2 = 3 in Fig. 8, which makes it possible to detail all the phases, but nothing prevents to have N2 = 1 (no symmetry), or N2 = 2 ). Since <B> Ni </ B> and N2 are two prime numbers between them, we return to the same situation (except for this rotation of a <B> N2 </ B>, no turn) every l / N1.N2 turns (here, every <B> 301 "</ B> turn), and all the Niéme (here, every tenth) cycle heating admission - relaxation - exhaust.

As seen in fig. 8, constant volume heating is achieved by moving a cell in a relatively long constant width passage.

The expansion begins when the front piston of this cell meets an enlargement on the side of the stator. This simultaneously increases the volume available to the air of this cell, and a larger piston surface at the front than at the rear, which makes it possible to push the rotor in the direction of rotation, since this cell is precisely, at this moment, the one whose pressure is the greatest.

The exhaust and the intake start when the front and rear pistons of this cell are of the same width (its volume then reached its maximum, since it will then decrease, proportionally to the difference of surface between these two pistons, which difference change of sign). This escape and admission, which must take place at the same time, can be organized in two ways.

The first, shown in fig. 8, consists in introducing, from the stator, a temporary fixed wall just behind the front piston. The exhaust will be at the rear of this wall, until the arrival of the next piston (the temporary wall will then retract the time of its passage), while the admission will be just in front of this wall.

The second is to take advantage of differences in the density of cold air and hot air. It is thus possible, in an unseparated compartment, to extract the hot air from above and to introduce the cold air from below, without much risk that they mix.

One of the main difficulties lies in the contact between the rotating pistons and the walls (side and, if, they are not integral with the rotor, lower and upper) of the stator. This contact must be both watertight (with pressure differences up to '/ 2 atm.), Generate little friction, and pass over the pierced surface that constitutes the "shower".

With regard to this last point, it is conceivable that the floor of the cells is secured to the rotor, as well as the hot water supply system and the evacuation of the water warmed, which would allow the pierced surface to never come into contact with a rotating piston. It would simply be necessary to turn the shower on and off at the right time, not just the automatic passage of the cell in coincidence with the showers (fixed) in the constant width passage.

Moreover, the slowness of the process makes it possible to imagine a system of contact between the mobile piston and the stator, in "caterpillar": there is no sliding, simply two flexible contacts, in the manner of a broom. wiper perpendicular to a windshield. Each one seals a big half of the time, and takes off, to advance, twice as fast as the piston itself, the other half of the time.

All of the above devices can be transposed to any variant that would exchange the roles of the stator and the rotor (outer rotor stator, non-rotating pistons folding in the stator and providing a sliding contact on the rotor surface that would have a non-circular profile, etc.). The principle of action and reaction ensures that in all these configurations, a torque between the rotor and the stator would develop in any case.

With regard to the transmission of power to electrical machines, the advantages of the system are the removal of the crank-rod mechanism, and the resolution by a simple choice of profile of the problems of heating at constant volume of the air and the constancy the couple produced. The disadvantages are the large size of the system under pressure and moving, and the slowness of the rotor, hence the interest of having sufficiently low N2. g) <I> <I> System Supply <I> in Cold Air </ I> With "showers" to heat the air to <B> 60'C, having the air at an initial temperature of 0 C instead of <B> 30'C </ B> makes it possible theoretically to obtain twice as much pressure difference, hence a piston stroke that is twice as long, and electricity production per piston cycle, four times higher. The most efficacious improvement of the yield therefore consists in taking advantage of the consequence of the very low content of water vapor in the desert air: the fact that the nights are very cold. The air supply of the plant will therefore be preferably from night air, stored before dawn (at the coldest hour of the day) in a very large volume (up to 0.1 km ') and protected from solar radiation by a cover reflecting light and infrared.

The reflective envelope surface, and therefore the cost of the system, can be reduced, at constant volume, if it is possible to take advantage of a natural relief: short gorges or can be closed over a certain length, circus, or even simple cliff from one to a few hundred meters high. The tightness of the contact with the rock walls does not need to be perfect, the cold air tending to stay down and the hot air at the top; the descent or ascent of the reflective cover can therefore be done with a rather rustic guidance, and be content to accompany the decrease in the volume of cold air due to consumption by the plant.

In sites without relief, storage can be done in one (or more) very large balloon (but which, unlike balloons, would remain on the ground). As for golf courses, the upper part of the balloon can be supported (or constituted - see below) by auxiliary balloons at HZ or He, so that the "filling" does not require pressurization, and consists of simply a lift of this cover as light as air (with openings on the top or on the sides, as desired). Once the ambient air is warmed up a little, the cold air can be operated by flowing by gravity.

Viewed from the outside, the envelope must have a beveled shape (connecting to the ground practically horizontally), on which the wind has the least grip. This cover can however, if necessary, be doubled inside a real balloon, flattened but constituting a closed envelope. The most elegant solution, which can even be relatively economical because of the minimization of the tensions it implies, is, by analogy with the characteristics of the construction of the balloon, to make these covers from elements ( for example parallelepipeds in waterproof fabric, filled with HZ or He) generally almost as light as air so as to facilitate their handling, and fixed to each other by systems such as slides or ventou ses, and magnetic rods, described above.

This cover must be completely horizontal in the evening and in the first half of the night, and on the contrary rather strongly convex (while offering a hold to the mini male wind) in the morning, when the air is the coldest, and remain it a a good part of the day, as long as the gas of the elements defined above (which may have better thermal contact with the cold air beneath it than with the atmospheric air which floats it) also remains cold enough. As a result, between day and night, there is a variable curvature and a difference in area, mainly distributed in areas of steeper slope.

This constraint can be managed in the following manner (see Fig. 9) A good part of the surface difference can result from an anti-expansion phenomenon: an element which, cold, has a rectangular section, tends, when the gas which it contains expands, to approach a form which maximizes its volume on a constant face, that is to say a square section. Its horizontal dimension therefore decreases with temperature. To take advantage of this effect while maintaining a minimum wind catch, one must either find a way to cover the entire area of slippery covers, or that the various elements involved are connected mainly in the middle of the walls to be joined, by strong bonds (slides, suction cups or equivalent) and, on the surface, reversible links (magnetic rods) at several levels.

The convex curvature is obtained on an intermediate element between those which have just been described, and the "normal" elements which constitute the top of the cover, thanks to the use, at the junction with the anti-dilator elements, of the same magnetic bonds, not at the same time at the top and at the bottom of the walls to be joined, but only at the top: the difference in length (in section in Fig. 9, in reality, of surface) between the lower and upper faces is sufficient to generate the desired curvature.

The concave curvature can be obtained either by applying the opposite principle of the one just described, or, more simply, by not using, in the corresponding areas, light gas balloons, but a simple stretched canvas. .

<I> h) </ I> <I> eventuality of a pre-compression of the air introduced into the plant </ I> To compress for example by 10% (0.1 atm) the fresh air introduced into the cylinder, which reduces its volume by 7% (PVy = cte, with y = 1,4) and increases its temperature by 3%, ie 8 to 9 K, it is necessary to provide a work equal to 0,05 atm x 0 , 07 V. The increase in pressure under the effect of heating by the shower is reduced by the effect of the 3% already obtained on the temperature. Instead of increasing by 20%, it will increase by: 10% + (20% - 3%), or about 27%. In both cases, the saturation vapor pressure of the water (0.2 atm) is added, which gives 0.47 atm instead of 0.4.

The relaxation (always roughly isothermal given the condensation of water vapor) will be with an amplitude of 43.5% of V; "t (47% of 93% of V) instead of 40% By approximating these isotherms by line segments, the net work produced will be, measured in atm x V, n, t, of: (% z x 43.5% x 47%) - (0.05 x 0.07) 0.098, instead of% Zx40% x40% = 0.08 This improvement in performance is explained by the fact that we release slightly less hot air and charged with water vapor, since the The relaxation is longer, and the fact that the heating of the air has been a little less irreversible, since the air is initially heated a little less cold.

If it turns out that the costs involved in storing cold air, the pressure resistance of the plant, and the lengthening of the piston stroke, are important, the principle described above and the use of the night air can be used alternately: at night, ambient air is used, which makes it possible to maximize the efficiency of the resistance at 1.4 atm obtained from 0 C; during the day, the same limit is reached with a lower rise in pressure due to heating with hot water, since the air is less cold, but it is replaced by pre-compression at the end of admission. fresh air, and the water of the solar pools being a little warmer during the day, we get about the same power, without bearing the cost of storage.

Conversely, if the costs of storing cold air, the pressure resistance of the plant and the stroke length are low, the pre-compression of the additional air and the use of stored night air can be used together: each advantage of the one and the other plays on the power reached and on the stroke of the piston, so, in theory, the efficiency of the whole is proportional squared of the difference of pressure obtained: each gain, in coldness of cold source as in precompression of the air, makes even more profitable the following gain, that it comes from the same effect or the other.

 In either case, only a complete techno-economic calculation would make it possible to know how much preliminary compression must be involved, which also complicates the sequencing of the exhaust, intake and heating phases of the engine. air, as well as the geometry to obtain the most stable torque at the output of the set of pistons.

<U> 4. Modification of the </ U> inner structure of balloons </ U> The relevance of water vapor heating does not come mainly from the fact that it increases the temperature of the air, but especially because it can then almost completely prevent it from decreasing during adiabatic relaxation. If, for any reason, the device described in point 3 above could not be achieved, the same logic could lead to change the internal structure of balloons, according to the following principle The vaporization of one mole of water consumes 40670 joules. If, in a hot air balloon, it is condensed at the end of the race, we obtain, during the climb, an Archimedes pressure of the order of 11 g (29 g -18 g), and at the top, 18 g water from which we will recover the poten tial energy. For a run of 5760 m, one obtains 1637 J. On the other hand, if this mole vaporizes immediately, it makes it possible to increase by 1.4 the temperature of 1000 moles of air (or of that of <B> 100 < Moles, etc.). As a result (at 300 K) an Archimedean pressure of 135 g (difference in density of 5.5 g / m 'applied at 24.6 m') and a gain of 7617 J. (in fact a a little less, because we start to empty the balloon before it reaches the top of its course, but we still have the quadruple 1637 J obtained above). It clearly appears that the advantage of the principle of water heating lies essentially in the fact of stabilizing the internal temperature of the balloon thanks to the latent heat of vaporization.

It therefore seems desirable to avoid the dilution effect of water vapor which, by decreasing its partial pressure (which is equal to its saturation vapor pressure), reduces its stabilization temperature (from 12 for a mixture to 50 / 50). This is possible by filling the hot-air balloon with a few thousand long vertical cylinders, of the order of the radius and of a height equal to that of the balloon, which alone will be filled with moist air. The rest will be filled with dry air, enjoying the latent heat of moist air without reducing its concentration of water vapor.

In fact, the basic design of the system (complete filling and complete emptying by air saturated with water vapor, tare rendered negative by the use of small auxiliary gas balloons) has three disadvantages, which one can remove, of course not without compensation, but by accepting this slightly different design of the balloon.

If we want the balloon to provide a significant force in the last kilometers of the race, it is necessary that the indoor air remains warm enough (at least 30, if possible more for a good performance) and wet. Now, as we have seen, it is in its moisture that most of its energy (latent heat) resides. It is therefore a shame to release it in the upper atmosphere, pure loss. At least we can try to recover the fresh water it contains but this requires a device for mixing with cold air outside, which increases the complexity of the whole.

Hence the three disadvantages that we can try to eliminate: the impossibility of recovering part of the latent heat of vaporization, the difficulty of recovering the corresponding fresh water, and the hydrogen or helium balloons.

Hydrogen balloons can be removed if it is accepted that the hot air balloon does not go down completely empty, but with a residue of hot air. The idea is then to only release pure air, albeit relatively hot, but dry, and keep the air moist (this option is therefore almost exclusive that of "air factories", since those -continually produced moist air whose outlet was the set of gulf mount). This is the best use of the long casings mentioned above, filled with a humid air which only returns by the "shower" to raise its moisture content, the rest being dry air that is introduced to the soil and which is released at 6000 m altitude.

Provided that the thermal exchanges between the two parts of the balloon are good, the stabilization of the temperature of the balloon thanks to the latent heat of the water vapor can be obtained from the order of one tenth of the total volume : the volume of air to be passed under the "shower" is therefore lower, and one can use water of increasing temperature, up to nearly 100, to obtain a hot air balloon temperature close to this value, without having to regret that this improvement results in more and more heat losses of vaporization during the emptying of the balloon at the top of its race.

 I. <B> GENERAL PRINCIPLES </ B> <B> A. Description of Principles </ B> used <B> 1 </ B> 1. Nature of the working fluid 1 2. Use of hot-air balloons 2 3. Installation site best suited to the hot-air balloon race 3 4. Use of air wet and combined seawater desalination function 3 5. Production of hot water used 4 6. Pre-spray of water at constant volume 5 7. Thermodynamic and economic efficiency 6 <B> B. Comparison with competing techniques 6 </ B> II. <B> PRODUCTION OF ELECTRICITY AND POSSIBLE WATER </ B> <B> SWEET WITH MONTGOLFIÈRES 7 </ B> <B> A. Hot air balloon structure 7 <B> 1. </ B> Objectives to be achieved 7 2. Choice of a relatively rigid but light structure 8 3. Constitution of solid bricks 9 4. Assembly of textiles 10 5. Lower appendix use in low winds 11 6. Thermal characteristics of hot air balloons 12 <B> B. Operation of </ B> hot-air balloons <B> stricto sensu 12 </ B> 1. Hot-air balloon filling position 12 2. Hot air balloon hot-air filling and starting 14 3. Balloon climb analysis and sizing 14 a) Dry air balloon 14 b) Air balloons with steam saturated air 15 4. Return of hot-air balloons and stowage 17 <B> C. </ B> Ground-based facilities <B> 18 1. Transformation of the balloon traction power in electrical power 18 2. Overall management of powers, speeds and cycle times 20 <B> III. PRODUCTION OF AIR USED AS MOTOR FLUID 21 </ B> <B> A. </ B> Heating <B> of Air in Solar <B> Baffles 21 </ B> 1. Transformation radiative energy in heat 21 2. Dimensioning and interest of linking together several glass roofs 23 3. Storage of heat and thermal insulation of the floor 25 <B> B. Vaporization of moderately hot water in the air 26 </ B> 1. Use of solar pools 26 2. Other possible sources of hot water 28 3. Improvement of energy efficiency by vaporization of water at constant volume29 a) Principle of the "air plant" 30 b) First variant of the crank-handle principle: crank with groove 32 c) Second variant of the crank-handle principle: use of non-circular gears 33 d) Third variant of the crank-crank principle : alternative connection of the two-piston connecting rod in phase opposition 34 e) Fourth variant of the crank-rod principle: use of quasi-epicyclic movements 34 f) Adaptation of the rotary piston motor 38 g) Supply of the system in cold air 40 h ) Possibility of pre-compression of the air introduced into the plant 41 4. Modification of the internal structure of balloons 42 <B> CLAIMS (1 to 62) 41 </ B>

Claims (14)

1) Device for producing mechanical energy or electricity, originating from a source of available energy with low cost but at low temperature, characterized in that: the driving fluid is the atmospheric air heated in contact with this energy source; the "piston" consists of hot-air balloons whose course can extend over several km, thus using the upper troposphere as a cold source. 2) Device according to claim 1 characterized in that the balloon tare is zero or negative through the use of auxiliary balloons inflated with a light gas (hydrogen or helium). 3) Device according to claim 1 or claim 2 characterized in that the best performance is obtained by a race whose first part is done with a constant amount of air and a growing volume, and the second part with a constant volume and a decreasing amount of air. 4) Device according to any one of the preceding claims, characterized in that the balloon is constituted around two circular frames which, in the closed position, enclose the fabric, protect it from the wind, and constitute a beveled outer edge providing a grip at lateral wind quite weak and which, in the deployed position, delimit a vertical cylinder of fabric prepared to fold by forming folds of about ten meters wide between these two frames, from ripple primers, for example under form of horizontal bulks very extensible, filled with helium, imposing on the envelope part of their curvature, and / or a geometry of the spindles alternating narrower places and wider passages. 5) Device according to the preceding claim, characterized in that these frames consist of elements which, so as to be easily manipulated, are almost as light as the air through the use of hydrogen or helium, substituted for air in the manufacture of expanded polystyrene and / or filling the voids of a rigid structure made for example of aluminum or one of its alloys. 6) Device according to any one of the preceding claims, characterized in that the textile parts constituting the balloon are connected by fasteners whose rupture limit is high but lower than that of the fabric itself, and can be closed or open effortlessly by an action that only the user can cause, such as zippers, or linear suckers. 7) Device according to the preceding claim, characterized in that the connections described therein are supplemented by rods attached to the fabric and provided with magnets providing, in normal weather, a smooth facade, but capable, in case of burst of wind, yield and then return to the closed position having dissipated some of the energy transmitted to the canvas by the turbulence of the air. 8) Device according to one of the two preceding claims, characterized in that the linear mass of the structures described above, a source of deformations of the fabric, is compensated by the buoyancy of an expansible helium filled with helium . 9) Device according to any one of the five preceding claims, charac terized in that the horizontal folds mentioned in claim 4 are lined with magnetic rods identical to those of claim 8, so that the filler of the hot air ballooning is done by making (reversibly) yield one by one these links, which makes it possible to avoid that during its filling its wall is vulnerable to the wind. 10) Device according to any one of the six preceding claims, characterized in that a wide inexpensive fabric skirt and little worked because designed to operate only in stable weather, can be deployed under the balloon to increase its volume , thus allowing either a larger injection of hot air or a longer conservation within the system, the air mass initially introduced and which, as noted in claim 3, expands, therefore overflows hot air balloon, as the pressure decreases. 11) Device according to any one of the preceding claims, characterized in that the conservation of heat in the balloon may result in a reduction of losses by convection and conduction through the suspension at the "ceiling" of the balloon very light canvases which behave like additional "peels" near the envelope, and a reduction of losses by infrared radiation thanks to the opacity of the same peels, or the application inside the balloon of a reflective material. 12) Device according to any one of the preceding claims, characterized in that, without it being necessary to bring the hot air balloon itself to the ground or close distance thereof, its reloading hot air is done by a textile cylinder, guided by means of free contacts (rings) by the cables (or straps) outside the hot-air balloon, and whose base is collected by a funnel which directs it to the docking system. 13) Device according to any one of the preceding claims, characterized in that for the hot air supply hot air balloon (it is done directly or according to the device provided in the preceding claim) for the last meters before assembly, a ferromagnetic attraction allows the exact positioning of the ring at the base of the hot-air balloon or textile cylinder of the preceding claim, on an equivalent ring located at the top of the outlet mouth of the air hot on the ground. 14) Device according to any one of the preceding claims, characterized in that, in order to combat the possibility of large oscillations of the tractive cables, the first pulley on which they pass is in fact made of several pulleys cerning the cable by occupying all 360 around him. <B> 15) </ B> Device according to the preceding claim, characterized in that fluid damping systems of coefficients adapted to the different possible frequencies of resonance of the cables are interposed in the connection by which the "first pulley" cited in the preceding claim is attached to the frame, and also at the level of lower pulleys. 16) Device according to any one of the preceding claims, characterized in that, so as to exert lower stress on the hot air balloon and in particular on its fabric, the towing cables are replaced by wide straps containing as many fibers and transmitting globally the same traction to identical drums, the devices provided in the two preceding claims being adapted accordingly. 17) Device according to any one of the preceding claims, characterized in that the winding drum of the cable (or strap) tractor is not fixed to the installation by an axis, but by two ball bearings, whose inner radius is equal to the outer radius of the drum. 18) Device according to any one of the preceding claims, characterized in that the number of cables or straps is calculated taking into account that their winding on the drums (in equal number) is all the easier as this number is tall. 19) Device according to any one of the preceding claims, characterized in that, so that the windings are made in a perfectly coordinated manner, and that the drums can be connected mechanically while allowing the control of each cable, the fingerprints of cables are preformed on the drums. 20) Device according to any one of the preceding claims, characterized by mechanisms for controlling and correcting the verticality of the balloon and the voltage of each cable relative to its immediate neighbors. 21) Device according to any one of the preceding claims, characterized in that, for better control of the hot air balloon from the ground, the towing cables rejoin the ground being widely spaced relative to each other. 22) Device according to any one of the preceding claims, characterized in that, in the transitional phase where the power demand increases (mutatis mutandis, dimi nue) sharply and where a correction consisting of allowing the balloons to accelerate to increase the power produced would initially the opposite effect, the necessary power is taken from the consumption of large electrolysers using, in competition with the network, the energy produced. 23) Device according to any one of the preceding claims, characterized in that the driving fluid is atmospheric air simply heated by passing through a canopy whose floor is lined with black bodies. 24) Device according to the preceding claim, characterized in that the air outlet of the canister operates on the principle of solar chimneys, so as to suck the air without the need to place many fans. 25) Apparatus according to any one of the two preceding claims, characterized in that the canopy is thermally connected with large masses (eg water) allowing storage of heat, and therefore a functioning at the same time diurnal , in sunny or overcast weather, and at night. 26) Device according to any one of the three preceding claims, characterized in that several balloons can be inflated from the same canopy, allows as long as there is at any moment or almost at any time a balloon stowed to the canopy, and that the dilation of the air finds in this balloon an outlet. 27) Device according to the preceding claim, characterized in that the lateral air inlet locks and the air circulations within the canopy are adjustable, so as to slow the arrival of the nearest unit, and to accelerate those of the most distant arrivals, so that each hot air balloon, whatever its place of departure, fills with all or almost all the air of the canopy. 28) Device according to any one of the five preceding claims, characterized in that the use of methods for improving the heat capture of the solar radiation is preferably located in the areas where the air comes after having circulated longer in more external parts of the canopy, and where, moreover, it is necessary, for reasons of flow of the air, that the canopy has a greater height. 29) Apparatus according to any one of the six preceding claims, characterized in that the double glazing effect can be optimized by placing at mid-height or at any intermediate height, the 2nd window. 30) Device according to any one of the preceding claims, characterized in that the air of the balloon is charged with moisture by the evaporation (in "showers") of water from any source of low temperature heat of which water is the heat transfer fluid, which is available in large quantities, and is not otherwise profitable, this hu midity making it possible firstly to reduce the average molar mass of the gas mixture of the hot-air balloon, and then to obtain a condensation inside the balloon, which allows at the same time to recover fresh water (especially if the evaporated water was salty) and rich in gravitational potential energy, to increase the relative temperature difference between the indoor and outdoor air by recovering the latent heat of vaporization, and helping to solve the dilemma of increasing the maximum size of the golf course or the loss of gas. hauds. 31) Device according to the preceding claim and claim 2, characterized in that the valuation of the gravitational potential energy results from a larger amount of hydrogen or helium in the auxiliary balloons, fully compensated, during the game of the rise which takes place after the condensation and during descent, by the weight of the condensed water (collected at the bottom of the balloon as well as at the base of the "skirt" described in claim 10), but not compensated during the first part of the climb, which results in an additional upward force equivalent to the weight of this water, over a distance equal to the altitude at which the condensation takes place. 32) Device according to one of the two preceding claims, characterized in that the salt water to be evaporated is heated by the technique known as "solar pools". 33) Device according to the preceding claim, characterized in that the improvement of the behavior of the surface of the solar pools may result from the existence of waves propagating on the surface or an additional layer of thermal insulation, antireflection and / or anti-evaporation. 34) Device according to one of the two preceding claims, characterized in that the hot water is collected at the bottom of the solar pools with large pipes drilled, sweeping angular sectors, jointly with devices for varying heights , the return of some of the water lukewarm and enriched with salt, and the addition of new sea water. 35) Device according to the preceding claim, characterized in that the parameters (height, possible mixtures) of the reinjection of the salt-enriched water and new seawater are adjustable (since on average, return as much water and salt as is harvested), depending on the weather or other management choices, including the possibility of using a preheating pond, the water of which feeds higher temperature. 36) Device according to any one of claims 23 to 28 and 32 to 35, charac terized in that the thermal insulation to the ground can, without major inconvenience, be reduced to an insulating circular skirt around the energy sensor solar (canopy or basin), about ten meters down, stopping side leaks, providing horizontal insulation under the sensor, since heat flows in this direction can be considered as long-term storage rather only as losses. 37) Device according to claims 30 and 31, characterized in that the heating of water (salt or not) results from the use of geothermal energy. 38) Apparatus according to claims 30 and 31, characterized in that the heating of water (salted or not) results from the use of the cold source heat of thermal power plants or nuclear. 39) Device according to the preceding claim, characterized in that a particular device for vaporization of water in atmospheric air is not necessary in the case of water cooling tower plants, which can also play the role of solar chimneys allowing the flight and the management of balloons. 40) Device according to any one of the preceding claims, characterized in that the air is preheated by contact with black panels, under nets capable of fulfilling the function of obstacle to the escape of hot air to the top in so far as the air is guided and maintained in slight underpressure with respect to the atmosphere, by fans 41) Device according to the preceding eight claims except for the last, characterized in that the heating of the air, motor fluid, and its saturation in water vapor, can be used, on land, in "cylinders" of reasonable dimensions (some 104 m3) in cycles of a few minutes, where it is heated and humidified to volume constant, then undergoes a relaxation which generates the motive power then transformed into electrical power, and can finally either be released directly into the atmosphere, or feed (directly or after a new enriched The hot-air balloons described in claims 1 to 22 and 30 and 31. 42) Device according to the preceding claim, characterized in that several out-of-phase cells constitute an assembly which, in a continuous and as regular manner as possible, absorbs cold air and hot water, produces electricity, and releases warm air still wet. 43) Device according to the preceding claim, characterized in that the collection of the successive mechanical powers is by analogy with the various cylinders of a combustion engine, with this difference that the crank is replaced by a disc equipped with a groove, connecting the center of the disc to a point near its circumference, and where can move the end of the rod, so that during half of the cycle, the piston remains stationary, allowing to heat and humidify the l air at constant volume (see Fig. 2). 44) Device according to the preceding claim, characterized in that the horizontal discs described above, which may have a groove on each of their faces, are arranged one above the other, and rotate in the opposite direction but at the same speed because of their connection by conical gears rolling between tracks located on and under the circumference of these discs, one of these wheels ensuring the transmission of the total torque to the electrical machines. 45) Device according to claim 42 (and therefore alternative to the two previous claims), characterized by the use of a rod-crank system extended by a non-circular gear wheel driving a complementary gear wheel, both by tangential contact and, for the normal component of the force, with the aid of a mobile carriage, the quasi-immobilization of the piston during nearly half of the cycle, resulting from a strong widening of the minimum abscissa bearing of the piston during of the cycle, thanks to the use of these non-circular gears (see Fig. 3). 46) Device according to the preceding claim, characterized in that the carriage is motorized and controlled by the difference in spacing between its pair of front wheels and its pair of rear wheels. 47) Device according to claim 42, characterized in that two "cylinders" neighbors operate with a phase shift of half a cycle, so that the same rod is connected half the time to the piston of one of these cylinders and the other half to the piston of the other cylinder, and drives a crank "normal", in the sense that it is possible to have a single solid joining all the cranks. 48) Device according to claim 42, described in Figures 5, 6 and 7 and character ized by the fact that the crank-crank joints describe quasi-epicyclic trajectories with three points, one of whose sides is comparable to an arc of circle and allows a quasi-immobility of the piston during the heating phase of the air, which can thus take place during a third to a half of a cycle, the power produced by three air heating cylinders, distributed at 120 and phase shifted by one third of period, being transmitted by three connecting rods to the same crank, then to a vertical crankshaft secured to a circular and horizontal track (or cogwheel) rolling without sliding inside a fixed circle of triple ray 49) Device according to the preceding claim, characterized in that the vertical crankshaft described above and whose axis follows the circle radius 2 r, gathers n cranks distributed around this xe, on a circle of radius r ,, at angles of <B> 360 '</ B> / n. 50) Device according to any one of the two preceding claims, characterized in that the transmission of mechanical power is then via a piece of vertical axis located in the center of the device, the same radius or radius less than that of the toothed wheel (integral with the crankshaft) which drives it, and therefore making at least 4 turns in a heating-expansion - exhaust - intake cycle. 51) Device according to any one of the three preceding claims, characterized in that the crankshaft is extended upwards, and terminated by a pin which, through a rolling ring without sliding on a track practiced in a fixed structure forming a ceiling, based on this structure and thus on the frame 52) Device according to any one of the preceding claims, charac terized in that the bearing of the base of the crankshaft on the frame is via of the flat elliptical ring of FIG. 6, which allows the composition of two rotational movements, achievable by means of ordinary bearings, unlike the epicyclic movement of the crankshaft itself relative to the frame. 53) Device according to any one of the preceding claims, characterized in that the phases of admission and exhaust of the driving fluid are made with the aid of a rear piston not subjected to significant efforts during its movements. 54) Device according to claims 41 or 42, characterized, as shown in Figure 8, in that: the "air plant" consists of a rotor comprising pistons subjected to an outward force, which the plates permanently against the wall of the stator, whose profile can be freely chosen, in particular to allow a long enough time of heating the air to about constant volume through the displacement of a cell in a passage with constant width relatively long; the expansion takes place when the forward piston of this cell meets a widening on the side of the stator, and until its front and rear pistons are of the same width; then start the exhaust and the admission, which must take place at the same time, which can be organized by introducing, from the stator, a fixed temporary wall, just behind the front piston, behind which will make the exhaust, while admission will be just in front of this wall; all of the above devices can be transposed to any variant that would exchange the roles of the stator and the rotor (outer rotor stator, non-rotating pistons folding in the stator and ensuring a sliding contact on the rotor surface that would have a non-circular profile, etc.). 55) Device according to the preceding claim, characterized in that the temporary fixed wall is removed, the cold air and hot air coexisting in an unseparated compartment, which fills with cold air from below while the Hot air is extracted from the top. 56) Apparatus according to any one of the two preceding claims, characterized in that the contact between the rotating pistons and the or the walls of the stator is "chenille", without any sliding, but with two flexible contacts, as a wiper blade perpendicular to a windshield, each sealing half the time, and moving the other half. 57) Device according to any one of the sixteen preceding claims, characterized in that the expansion can begin before the end of the heating, which allows to clip the pressure curve and to reduce the specifications of resistance to pressure. 58) Device according to any one of the seventeen preceding claims, characterized in that the air introduced into the plant is collected before dawn under very large reflective covers (visible and infrared), forming a dome on the ground or closing a natural escarpment (throat, ...) and used throughout the day with a very low initial temperature, so a relatively large increase in temperature during heating by hot water, increase to which are proportional the pressure difference obtained and the change in volume during the relaxation. 59) Device according to the preceding claim, characterized in that, by analogy with the characteristics of the elements of the hot air balloon, the covers for the collection and preservation of cold night air to feed the "air factories" consists of waterproof fabric elements, filled with H2 or He) generally almost as light as air so as to facilitate their handling, and fixed to each other by systems such as slides or suction cups, and magnetic rods, described in claims 6 and 7. 60) Device according to the preceding claim, characterized in that, in the case of a cover to form a dome, the geometry of these elements, as well as their connection systems, allow to take advantage of the fact that the dome is most accentuated at the hours when the gas of its elements is, in particular thanks to the contacts with the interior air, the coldest, and that inversely, the opening is flattened when its elements are warmed, so that these adaptations are made without generating strong tensions, using the principles outlined on p. 41 of the description and illustrated in FIG. 9. 61) Device according to any one of the preceding claims, characterized in that after the end of the intake phase, the driving piston can be used for a pre- compression of the fresh air, before the start of the heating, which, by accepting a longer detente and an increase of the pressure resistance specifications, makes it possible to increase the output of the plant, by increasing the power without increasing the amount of heat consumed and without increasing in such large proportions the amount of cold air introduced. 62) Device according to any one of claims 30 to 38, characterized in that the balloons are filled with long vertical cylinders, only filled with moist air (which allows the rest to be filled with dry air benefiting from the latent heat of the humid air without diminishing its concentration of water vapor) and destined to be alone emptied once the hot-air balloon reaches the top of its course, the humid air of the intestines being re-enriched with water vapor at his return to earth.