AU2010257517A1

AU2010257517A1 - Solar field and method for assembling the solar field

Info

Publication number: AU2010257517A1
Application number: AU2010257517A
Authority: AU
Inventors: Ori Gil; Shmulik Klapwald; Naim Levi; Yigal Sharon
Original assignee: Siemens AG; Siemens Concentrated Solar Power Ltd
Current assignee: Siemens AG; Siemens Concentrated Solar Power Ltd
Priority date: 2009-06-08
Filing date: 2010-06-08
Publication date: 2011-12-15
Also published as: EP2440857A1; CL2011003045A1; MA33337B1; WO2010142664A1; CN102803862A; IL216389A0; BRPI1012974A2; US20120174910A1

Abstract

This invention relates to a method for automatically assembling a solar field, the method comprising following steps: a) Providing at least one solar collector unit (100) with a radiation concentrator collector comprising a radiation absorber with an absorber tube (106) for a flow-through of a heat transfer medium and a parabolic mirror (102) for focusing solar radiation onto the absorber tube of the radiation absorber for heating up the heat transfer medium flowing through the absorber tube; b) Transporting the solar unit to a target location of the solar field; and c) Assembling the solar unit on the target location of the solar field. Additionally a solar field with a plurality of prefabricated solar collector units is provided.

Description

WO 2010/142664 PCT/EP2010/057980 1 Description SOLAR FIELD AND METHOD FOR ASSEMBLING THE SOLAR FIELD 5 FIELD OF THE INVENTION This invention relates to a solar field and a method for assembling the solar field. 10 BACKGROUND OF THE INVENTION Amid concerns over global warming, and forecasts of both the depletion of non-renewable energy sources and rising power demand, suppliers of energy are increasingly seeking 15 alternative primary sources of energy. One such source of energy is solar energy, and one way of utilizing solar energy is with a solar thermal power plant. One type of solar power plant comprises a solar field which 20 utilizes a "radiation concentrator collector" which concentrates the solar radiation by focusing it onto a smaller area, e.g., using mirrored surfaces or lenses. In this system, a reflector, which is typically parabolic, receives and reflects (focuses) incoming solar radiation onto 25 a radiation absorber, which is formed as a tube. The tube radiation absorber is concentrically surrounded by a treated glass enclosure tube to limit the loss of heat. The collector system further includes means to track the sun. 30 The tube radiation absorber is made of metal with a coating having a high solar radiation absorption coefficient to maximize the energy transfer imparted by the solar radiation reflecting off the reflector. A heat transfer medium (e.g. heat transfer fluid (HTF), which is typically a liquid such 35 as oil, flows within the tube radiation absorber. The thermal energy is transported by the HTF to provide energy to, e.g., a thermal-electric power plant to drive one WO 2010/142664 PCT/EP2010/057980 2 or more power-generation systems thereof, in order to generate electricity in a conventional way, e.g., by coupling the axle of each of the turbines to an electric generator. One such example of a thermal-electric power plant is a 5 steam-electric power plant, which uses thermal energy provided thereto to produce steam to drive turbines thereof, which in turn drive a generator, thus generating electricity. Throughout the solar field, the HTF flows within a tube, 10 which is partially constituted by the tube radiation absorber. The entire length of the tube should be designed so as to limit thermal losses therefrom. Along much of its length, it is surrounded by a tube or pipe of a larger diameter, with the space therebetween being evacuated in 15 order to limit heat loss due to convection. SUMMARY OF THE INVENTION It is an object of the invention to provide an easy and cheap 20 method for building up a solar field. A further object of the invention is a solar field which can be cheaper manufactured with respect to solar fields of the state of the art. These objects are reached by the claims. 25 According the invention a method for automatically assembling a solar field, the method comprising following steps: a) Providing at least one solar collector unit with a radiation concentrator collector comprising a radiation 30 absorber with an absorber tube for a flow-through of a heat transfer medium and a parabolic mirror for focusing solar radiation onto the absorber tube of the radiation absorber for heating up the heat transfer medium flowing through the absorber tube; b) Transporting the solar unit to a target 35 location of the solar field; and c) Assembling the solar unit on the target location of the solar field.

WO 2010/142664 PCT/EP2010/057980 3 The providing the solar unit comprises a manufacturing of the solar unit. The location of the manufacturing differs from the location of usage of the solar unit. 5 In a preferred embodiment a solar collector unit is used having a tube support for supporting the absorber tube and/or having a reflector support for supporting the parabolic mirror and/or having a mirror tracker for tracking the parabolic mirror based on the beaming direction of the 10 radiation of the sunlight. In a further preferred embodiment a checking of the solar collector unit is carried out before the transporting the solar unit to the target location. The checking the solar 15 collector unit includes preferably a measuring of at least one characteristic of the absorber tube and/or a measuring of at least one characteristic of the parabolic mirror. E.g. such characteristics are the absorptivity of the absorber tube for sunlight or a reflectivity of the parabolic mirror 20 for the sunlight. A testing of the solar units is executed before they are installed. By this cost can be saved due to that fact that just tested solar units are used for the solar field. 25 In a further preferred embodiment a plurality of solar collector units are provided and assembled together at the target location of the solar field. Especially all of the solar units of a solar field are manufactured and tested before the solar field is built up with them. 30 For the transporting the solar units in principle different transport vehicles can be used. But special designed transport vehicle for the transporting the solar collector unit are preferred. The vehicles are designed such that the 35 solar units can be supported in a save way. According to another aspect of the invention a solar field with a plurality of prefabricated solar collector units is WO 2010/142664 PCT/EP2010/057980 4 provided. The solar collector unit are assembled together, wherein each of the solar units comprises a radiation concentrator collector comprising a radiation absorber with an absorber tube for a flow-through of a heat transfer medium 5 and a parabolic mirror for focusing solar radiation onto the absorber tube of the radiation absorber for heating up the heat transfer medium flowing through the absorber tube. BRIEF DESCRPTION OF THE DRAWINGS 10 Further features and advantages of the invention are disclosed by the description of exemplary embodiments with reference to the schematic drawings. 15 Fig. 1 is a perspective view of a typical solar concentrator as part of a solar thermal power plant; Fig. 2 is a cross-sectional view of the heat collecting element (HCE) taken along line II II in Fig. 1; 20 DETAILED DESCRIPTION OF THE INVENTION As illustrated in Figs. 1, there is provided a solar concentrator 100 built up by a plurality of solar collector 25 units. The solar concentrator 100 is part of a solar thermal power plant (not illustrated) and comprises a reflecting surface of a mirror 102, which may comprise a plurality of light concentration devices (LCDs) 104. The reflecting surface 102 extend linearly and/or along a curved path dozens 30 of meters, and has a parabolic cross-section. The mirror is a parabolic mirror. As such, a tracking mechanism (tracker, not illustrated) is provided in order to ensure that the reflecting surface 102 faces the sun, thereby concentrating solar radiation impinging thereupon toward it geometric 35 focus. A heat collection element (HCE, absorber tube of the radiation absorber) 106 is provided along the focus of the parabola of the reflecting surface 102, thus receiving the concentrated solar radiation.

WO 2010/142664 PCT/EP2010/057980 5 As seen in Fig. 2, the HCE 106 comprises a tube radiation absorber (TRA) 110 through which a thermal fluid flows, surrounded by a glass tube 112 along its length. This tube is 5 called UVAC (Universal Vacuum Air Collector).A thermal fluid, which is used to heat a working fluid in a separate loop to drive a power-generation cycle, flows within the TRA. The thermal fluid is heated by the concentrated solar radiation. The space between the TRA 110 and the glass tube 112 is 10 evacuated in order to minimize heat loss due to cooling of the thermal fluid within the TRA by convection. Each end of the glass tube 112 may be enclosed by flexible external shield member (not illustrated). 15 HCE support posts (absorber supports) 108 are provided, e.g., at regular intervals along the length of the HCE, to maintain the position of the HCE 106 at or near the focus of the parabola of the reflecting surface 102. They are designed to pivot about a bottom end thereof, in the direction along 20 which the HCE extends. The solar collector unit (solar field basic component) is approximately 12 meters long and 5.7 meters wide and consists of a main torque tube, a reflector support, and reflectors. 25 For example eight solar collector units are assembled together to form a solar collector assembly (SCA). Metal base columns are based on a concrete foundation and holding the parabolic mirrors. A drive pylon is where the hydraulic system is located in order to rotate the solar complete 30 collector assembly according to the sun's movement. All electrical & communications panels are mounted on these pylons. By the invention the solar field as a part of a complete 35 power plant can be assembled automatically. The parabolic mirrors (parabolas) and the triple UVACs will be assembled at the site, i.e., at the Portable Assembly WO 2010/142664 PCT/EP2010/057980 6 Building (PAB), and will be dispatched to the Solar Field, to be installed according to a construction plan. The construction plan defines a dispatch of the other components of the solar field as well (pylons, crossover 5 pipes, ball joints, risers) so as to coordinate the timing of their arrival to their location in the solar field and their installation. The parabolas delivered at the outlet of the PAB will be transported to the solar field on a specially designed parabola carrying cart 10 (transport vehicle). The SCA is includes metal parts manufactured in standard process of steel structure. The driving system is installed in an assembly line. The final station includes a set of 15 tests to inspect and run a solar collector unit, to ensure the required performance of the solar collector unit. The optical accuracy achieved by drilling holes and mounting the drilled parts in the automatic assembly line. 20 The line includes special equipment that has been developed for mounting the parabola components. In the end of the line a measurement station inspects the final parabola accuracy. 25 A special gripper developed to transfer the parabola from the line to the wagon and later to lift it onto the SCA. In contrary to existing methods which are mainly done by hand using conventional tools, the method concerning the invention 30 uses specially designed tools and vehicles which offer several advantages: - higher precision; - better quality assurance; 35 - faster assembly time; - less manpower; - lesser chance for human errors; - lesser depreciation; WO 2010/142664 PCT/EP2010/057980 7 - less sensitive to weather conditions; - more flexible in the assembly process; - better control in the assembly process; - better control on the whole process (project schedule, 5 parts flow, inventory management, etc.); - efficient logistic of the assembling; - safeness of the whole process; - reliability of the manufacturing method an reliability of the resulting solar field.

Claims

1. Method for automatically assembling a solar field, the method comprising following steps: 5 a) Providing at least one solar collector unit with a radiation concentrator collector comprising a radiation absorber with an absorber tube for a flow-through of a heat transfer medium and a parabolic mirror for focusing solar radiation onto the absorber tube of the radiation absorber 10 for heating up the heat transfer medium flowing through the absorber tube; b) Transporting the solar unit to a target location of the solar field; and c) Assembling the solar unit on the target location of the 15 solar field.

2. Method according to claim 1, wherein a solar collector unit is used having a tube support for supporting the absorber tube and/or having a reflector support for 20 supporting the parabolic mirror and/or having a mirror tracker for tracking the parabolic mirror based on the beaming direction of the radiation of the sunlight.

3. Method according to claim 1 or claim 2, wherein a checking 25 of the solar collector unit is carried out before the transporting the solar unit to the target location.

4. Method according to claim 3, wherein the checking the solar collector unit includes a measuring of at least one 30 characteristic of the absorber tube and/or a measuring of at least one characteristic of the parabolic mirror.

5. Method according to one of the claims 1 to 4, wherein a plurality of solar collector units are provided and assembled 35 together at the target location of the solar field. WO 2010/142664 PCT/EP2010/057980 9

6. Method according to one of the previous claims, wherein a special designed transport vehicle is used for the transporting the solar collector unit. 5

7. Solar field with a plurality of prefabricated solar collector units which are assembled together, wherein each of the solar units comprises a radiation concentrator collector comprising a radiation absorber with an absorber tube for a flow-through of a heat transfer medium and a parabolic mirror 10 for focusing solar radiation onto the absorber tube of the radiation absorber for heating up the heat transfer medium flowing through the absorber tube.