Abstract: A heat receiver tube for absorbing solar energy and for transferring the absorbed solar energy to a heat transfer fluid is provided. The heat receiver tube includes a first partial surface, which is covered by a solar energy absorptive coating, and a second partial surface, which is substantially uncovered by the absorbing coating. Also provided is a parabolic trough collector with a parabolic mirror having a sunlight reflecting surface for concentrating sunlight in a focal line of the parabolic minor and a heat receiver tube which is arranged in the focal line of the parabolic mirror, wherein the heat receiver tube is arranged in the focal line such that the first partial surface with the solar absorptive coating is at least partially located opposite to the sunlight reflecting surface and the second partial surface at least partially averted to the sunlight reflecting surface.

Abstract: A solar reflective assembly includes a plurality of reflective segments radially configured to collectively at least partially define a dish-shaped reflector having a center axis, each reflective segment having a generally conical shape and being discontinuous relative to the conical shape of an adjacent reflective segment, and an elongated receiver having a length generally extending in a direction of the center axis. Each reflective segment reflects and focuses sunlight on the receiver along the length of the receiver.

Abstract: In a solar concentrator of a type having a curved mirror adapted to focus light onto an energy collecting body mounted at the mirror's focal axis, an alignment correction apparatus and method includes a linear array of light detectors adapted to be mounted at a bottom of and across a centerline of the curved mirror so as to intercept the shadow cast by the energy collecting body mounted along the focal axis. Outputs of each of the detectors are measured and plotted according to an order of arrangement of the light detectors on the array. The output results in a dip across adjacent detectors when a shadow falls across the array. A shadow detection means is adapted to determine a center point of the dip and correction means are configured to output a correction command if the center point is different from an optimal position.

Abstract: A solar collector includes a collecting mirror defining a radiation-transparent window. A collimating mirror re-reflects the collected radiation through the window to a black-body absorber located behind the collecting mirror. A working fluid flows through the black-body absorber to absorb the resulting power and to transfer the power to a utilization apparatus. The collecting and collimating mirrors may be elongated (cylindrical), or they may be axially symmetric. The working fluid may flow through a separate tube, or simply be contained by an aperture in a block of insulation.

Abstract: A boiler for a solar receiver includes a panel support structure. A boiler stay is operatively connected to the panel support structure. A panel stay is slideably engaged to the boiler stay. A boiler panel is operatively connected to the panel stay with the panel stay being affixed to a plurality of tubes of the panel. The boiler stay and panel support assemblies are configured and adapted to slide with respect to one another to accommodate thermal expansion of the boiler panel. In certain embodiments, a pin connects the boiler stay and the panel stay, wherein the pin is removable for installation and removal of the panel from the support structure.

Abstract: A parabolic trough solar collector system has a parabolic reflector used with an independently supported collector tube. The parabolic reflector has a reflective surface formed on a reflective surface support structure, supported by a circular support beam. This assembly rests on a plurality of support and drive rollers supported by a roller support arm, supported by a roller support column. The parabolic reflector assembly rotates against the rollers along a single axis to maintain a focus line of the parabolic reflector surface at the same location as the center of the circle described by the outer edge of the circular support beam. Located at this same focus line is the independently supported collector tube not attached to the parabolic trough reflector. The collector tube is supported on pipe roller hangers, which in turn are supported by a wire catenary system connected to support towers which straddle the parabolic reflector.

Abstract: Solar energy generates steam in a “once-through” configuration without recirculation, with closely managed steam quality, to produce wet steam from high-contaminant feed water without scaling or fouling. Feed water is pressurized, preheated, and evaporated in a series of pipes exposed to concentrated solar energy to produce a water-steam mixture for direct distribution to an industrial process such as enhanced oil recovery or desalination. Water flow rates are managed based on measurements of solar energy and steam production to manage variations in the solar energy. Steam generator piping system uses continuous receiver pipe that is illuminated by segmented parabolic mirrors enabled to track the sun. Provisions for steam generator piping recurring maintenance are provided. Thermal energy from hot condensate and/or from low quality steam is recaptured and warms inlet water.

Abstract: A focal display panel is situated in a parabolic solar energy collection array having reflective surfaces and a tube containing a working fluid to be heated. The panel comprises a target area to display patterns of light and shadow reflected from the array, and provides a visual means for determining the amount, if any, by which the focal point of the parabolic array misses the center of the tube containing the heated working fluid.

Abstract: The inventive solar trough field system (A) comprises multiple parabolic reflectors (1), support circles (3) of which the center coincides with the focus of the parabolic reflector (1 ) and which are used in order to support the reflector (1), core mechanisms (2) which are located on the center of the circles (3), guy wires (4) which connect the circle (3) and the core mechanism (2) to each other, side support units (5,5J) which bear the support circles (3) from their outer surfaces, lightweight filling materials (6) which support the reflectors (1) from their lower parts, thermal receiver tubes (11) which pass through the center axis of the circles (3). The parabolic reflectors (1) are rotated around the center axis of the circles (3), which is the focus thereof, and directed towards the sun. Thus, the parallel beams coming from the sun are concentrated in the thermal receiver tubes (11) which are located in the focus of the reflectors (1).

Abstract: The solar panel includes a housing for a heat collecting element, delimited by walls, one of which includes slits for the passage of solar rays. At least one reflective area is arranged to face the heat collecting element. At least one reflective strip is arranged outside the housing to face a respective slit so as to focus the solar rays received towards this slit. Elongated reflective elements are arranged side by side, and include coplanar flat bases, forming together the wall of the housing having slits and the flat base of at least one elongated reflective element forming a reflective area of this wall of the housing, and including one concave surface arranged to face the reflective strips such that the solar rays reflected by each concave surface are focused towards the corresponding reflective strip.

Abstract: The present disclosure provides an apparatus for collecting solar energy for electrical energy generation through one or more thermodynamic closed-cycle heat engines or the like. The present invention includes new designs for solar collectors that concentrate solar energy, and mechanisms for transporting and transferring the concentrated solar energy directly into the working fluid (e.g., a liquid, a gas, or a phase change substance) of the closed cycle thermodynamic engines without heating the outside surface of the engines. In an exemplary embodiment, the present utilizes an inflatable design for a dual-surface reflector which provides low cost and weight, protection from external elements, and the ability to inflate/deflate as required.

Abstract: Systems, methods, and apparatus by which solar energy may be collected to provide heat, electricity, or a combination of heat and electricity are disclosed herein.

Abstract: A solar reflection apparatus (60) is disclosed comprising a rotatable reflection (assembly 20) and a drive mechanism (12) which is operable to drive rotation of the reflection assembly (20) at its axis of rotation. The reflection assembly (20) comprises a curved linear reflector (4) defining a focal axis F, a counter weight (17) operable to balance the self weight of the reflector (4), and a support structure (15) via which the reflector (4) and counter weight (17) are rotatably mounted at locations along the focal axis F of the reflector (4). A solar collection apparatus (2) is also disclosed comprising a solar reflection (apparatus 60) as disclosed above and a heat collecting element (6), fixedly mounted along the focal axis F of the reflector (4).

Abstract: A solar panel configured to reduce contaminant accumulation thereon, including a surface adapted to harvest solar energy; and a vortex-inducing generator including chevron-shaped features disposed across at least a portion of the surface to reduce contaminant accumulation thereon by causing air flow passing over the surface to remove at least some contaminants deposited thereon and/or keeping particles entrained in the air flow to reduce deposition on the surface. A method of passively cleaning a solar panel includes providing the solar panel, and positioning the solar panel such that the leading edge is oriented to intercept a prevailing wind direction. A solar array includes a plurality of the solar panels, wherein each solar panel is positioned such that the leading edge is oriented to intercept a prevailing wind direction.

Abstract: The present invention relates to a solar cooking apparatus, comprising: a first solar reflector; a second solar reflector; a solar collection element; and a solar collection element holder, wherein the first solar reflector and the second solar reflector are concave, and opposably arranged and aligned with a solar collection element axis, each reflector having a range of motion on a plane perpendicular to the solar collection element axis, and focusing, radiation at the solar collection element, which rapidly heats when the first and/or second solar reflectors are in an opened position, the first and second solar reflectors protectably encase the solar collector when in a closed position. The solar cooking apparatus is adjustable and, in some embodiments, portable.

Abstract: Apparatus and methods related to solar energy are provided. A system includes a solar array supported to be angularly repositionable. A shuttle and linkage arrangement is coupled to the solar array. Thermally activated actuators sequentially control the linear translation of the shuttle such that the solar array is incrementally angularly repositioned over the course of a daylight period. Concentrated solar energy is used to heat the actuators in their sequential order. Systems for generating electrical and/or thermal energy, embodied as panels or other form-factors, are contemplated.

Abstract: A solar reflective condensing device, including a condensing film (2), a face-contour bottom plate (3), and a face-contour focusing support (4). The condensing film (2) is arranged on a top surface of the face-contour bottom plate (3). The face-contour bottom plate (3) is a thin plate, a bottom surface of which is attached to a top surface of the face-contour focusing support (4), and reproduces the shape of the top surface of the face-contour focusing support (4). The face-contour focusing support (4) includes a top optical surface (4a) and a focusing structure (4b) integrated with the face-contour focusing support. The top optical surface (4a) is positioned on the top surface of the face-contour focusing support (4), and a central point of the focusing structure (4b) integrated with the face-contour focusing support is positioned at a focus (f) of the top optical surface (4a).

Abstract: A parabolic trough solar collector system has a parabolic reflector used with an independently supported collector tube. The parabolic reflector has a reflective surface formed on a reflective surface support structure, supported by a circular support beam. This assembly rests on a plurality of support and drive rollers supported by a roller support arm, supported by a roller support column. The parabolic reflector assembly rotates against the rollers along a single axis to maintain a focus line of the parabolic reflector surface at the same location as the center of the circle described by the outer edge of the circular support beam. Located at this same focus line is the independently supported collector tube not attached to the parabolic trough reflector. The collector tube is supported on pipe roller hangers, which in turn are supported by a wire catenary system connected to support towers which straddle the parabolic reflector.

Abstract: A solar thermal collector includes a receptacle and a fluid conduit. The receptacle is evacuated to a subatmospheric pressure. The receptacle includes a window and a reflector facing the window. The window and the reflector are exposed to the subatmospheric pressure in the receptacle. The fluid conduit extends through the receptacle between the window and the reflector. The reflector concentrates solar radiation passing through the window onto the fluid conduit.

Abstract: A system for transferring torque between modules in a concentrating solar collector array. A trough collector system includes at least two modules, each module including a reflector having a reflective surface shaped to concentrate incoming radiation onto a linear tube, and a structural lattice attached to the reflector. The modules are constrained to rotate about a common axis. A torque transfer connection directly connects the three-dimensional structural lattices of the two modules at a location removed from the axis of rotation. Torque is thus transmitted between the modules by a force couple acting on the module. Also described are a method of transferring torque between adjacent trough collector modules, and a three-dimensional structural lattice configured for use in the system and method. Mechanisms for accommodating thermal expansion and contraction of the array are described. A drive system is described that imparts torque to a module near an edge of the module.

Abstract: The solar concentrator includes a base with a support frame that is rotatably connected thereto. A torsion box is tiltably mounted to the support frame to provide a wide range of movement of the torsion box and the finish surface thereon, which is preferably of a single plane parabolic shape that carries linear mirror strips. A receiver is mounted above the surface of the mirror strips at the focus of the parabola by a bracket to optimize reflection of radiation thereto. Plumbing transports liquid, such as water, through the receiver for heating thereof for various purposes, such as water desalinization. Thus, the solar concentrator is an optimized low cost and easy to manufacture solar concentrator.

Abstract: Parametric cylindrical solar collector with an optimized secondary reconcentrator and its design process, where the geometry of the primary reflector is an evolution of the Helmet collector concept towards a discontinuous curve that allows increasing the C/Cmax concentration to over 0.52 as well as reducing the wind loads. The structure is optimized to withstand the different loads to which the collector is exposed. The collector's center of gravity is brought closer to the axis of rotation of the collector. The geometry of the secondary reconcentrator is optimized and the collection efficiency of the collector is of 100%. The secondary reconcentrator is obtained partially mirroring the glass tube that keeps the vacuum in the absorber tube.

Abstract: A parabolic trough collector includes a parabolic mirror support structure with a parabolic mirror surface applied thereto, and an absorber support structure supporting an absorber tube. The parabolic mirror support structure and the absorber support structure are mechanically fastened in a fixed position relative to one another on a torsion tube that is arranged below the parabolic mirror surface, and mounted together with the parabolic mirror surface in a fashion capable of rotation about a parabolic trough collector longitudinal rotation axis. The torsion tube is arranged such that the parabolic trough collector longitudinal rotation axis coincides with the central longitudinal axis of the torsion tube.

Abstract: To secure stable heat collection efficiency and a safe and less expensive support/driving mechanism, a solar collector includes a tracking unit rotatably arranged around a drive shaft. The tracking unit includes a heat collection tube disposed in a longitudinal direction of the tracking unit and converts sunlight into heat. A collector has a reflection panel having a concave cross section in a lateral direction thereof for reflecting sunlight on the heat collection tube and a support member supporting the reflection panel from the backside. The heat collection tube 30 is fixed to the collector. The support member includes a tubular main pipe at a lowermost portion and in the longitudinal direction of the support member, and a plurality of flat support frames fixed to the upper portion of the main pipe in the lateral direction and vertically fixed to the backside of the reflection panel along the concave portion.

Abstract: A curved surface structure for reflecting solar light, heat or electromagnetic radiation is made by scoring two opposing pairs of curved bend lines along one pair of opposing edges of a sheet of bendable material, dividing it into a center section joined by curved bend lines to curved ribs, joined by curved bend lines to respective curved edges; bending the curved ribs down and curved edges up along the bend lines to nominally right angles to form a curved surface supported by two curved ribs and two curved edges. Two straight ribs and respective straight edges may be scored and formed on the other pair of opposing edges of the sheet. A backside sheet may be applied to the four edges. A widthwise corrugated, elongate right angle reinforcement member may be employed for strengthening the formed bend lines.

Abstract: The segment of a solar collector comprises a top side, a bottom side and a circumferential end face having at least one longitudinal side, wherein the longitudinal side forms a top edge with the top side and forms a bottom edge with the bottom side, and comprises a core structure having at least one core made of foamed material. The segment of a solar collector further comprises a shell made of one or a plurality of layers of a fiber material, wherein the shell at least partially covers the top side, the bottom side and at least the longitudinal side of the circumferential end face, wherein at least one layer of the shell extends about the top edge and at least one layer of the shell extends about the bottom edge, and a reflection layer disposed on the top side.

Abstract: Exemplary embodiments are disclosed that utilize waste heat from one or more aeroderivative turbines to provide backup thermal energy for a parabolic trough concentrating solar power (CSP) plant.

Abstract: In a reflector dish, a small quantity of elongate mirror-surfaced reflector panels are structurally integrated with a support framework that is configured to enable convenient shipping and on-site assembly and erection of a reflector dish assembly with an effective reflecting surface that closely approximates a desired parabolic dish shape with short focal length, synthesized from combination of the reflector panels originally procured as flat rectangular sheet metal panels and formed to provide the desired dish curvature. The panels can be conveniently shipped to location along with a corresponding quantity of reinforced crescent-shaped support frames to which the panels are made to attach as structural elements, by novel attachment hardware, for erection at the operational site.

Abstract: An apparatus is disclosed including: a trough shaped reflector extending along a longitudinal axis and including at least one reflective surface having a shape which substantially corresponds to an edge ray involute of the absorber.

Abstract: A passive solar collector utilizes a support constructed of precisely machined foam to simplify the construction and calibration of the reflective surface. Further improvements include sensor-based positioning, and a receiver having inflow and outflow conduits adapted to improve thermal efficiency.

Abstract: Concentrating solar collector systems that utilize a concentrating reflector to direct incident solar radiation to a solar receiver are described. In one aspect, the reflective surface is arranged to direct light to the receiver in a non-imaging manner in which the solar rays reflected from the opposing edges of the reflective surface are generally directed towards a central portion of the solar receiver. Rays reflected from selected central portions of the reflective surface are directed closer to the edges of the receiver than the solar rays reflected from the edges of the reflective surface. The described reflectors are generally intended for use in solar collector systems that track movements of the sun along at least one axis.

Abstract: A solar thermal power plant is provided. The solar thermal power plant includes a solar collection system configured for utilizing incident solar radiation to heat a heat transfer fluid (HTF) and a power block configured for utilizing the heated HTF to generate power. The solar collection system includes a plurality of pipes for carrying HTF characterized by a first degree of permeability to hydrogen, at least some of the pipes including portions exposed to the atmosphere, and including a membrane made of a material being characterized by a second degree of permeability to hydrogen, the second degree of permeability being higher than the first degree of permeability to hydrogen.

Abstract: The absorber pipe 10 according to the invention features a thermal opening 14, on which means are provided that reduce the radiation 26 emitted outwards from the absorbing surface 13 as a result of its operating temperature to an increasing extent as the operating temperature increases.

Abstract: This invention relates to a solar furnace. In particular, this invention relates to a solar furnace which is capable of raising the temperature of transfer medium. In use, the heated transfer medium can be used to generate electricity or put to other work, such as, for example, air conditioning, pasteurisation or desalination. In fact, for any situation that requires a source to generate work or power. The present invention describes a solar furnace for raising the temperature of a heat transfer medium, comprising a lens array for admitting incident thermal and solar energy onto a reflector portion and a pressure vessel. The reflector portion being generally shaped so as to concentrate said solar energy onto said pressure vessel. The pressure vessel having an inlet through which said heat transfer medium is injected and a central core which defines a continuous heat transfer path for said heat transfer medium to contact the surface of said pressure vessel and exit said pressure vessel at an outlet.

Abstract: Disclosed are systems and methods for controlling arrays of solar thermal energy collectors. Rows of the array are actuated sequentially or consecutively rather than concurrently.

Abstract: A solar collector including a linear receiver and an array of linear mirrors positioned to concentrate sunlight onto the linear receiver, with all of the mirrors in the array tracking solar motion in a direction perpendicular to the longitudinal axis of the receiver, a fraction of the mirrors tracking solar motion in a direction parallel to the longitudinal axis of the receiver and a two-axis steering mechanism adapted to combine the linear images formed by each linear mirror into a single linear image that remains focused on the linear receiver as the mirrors rotate about the two axes, with the linear receiver incorporating a secondary concentrator, and concentrated sunlight heating an atmospheric-pressure gas-phase heat-transfer fluid.

Abstract: A passive solar collector utilizes a support constructed of precisely machined foam to simplify the construction and calibration of the reflective surface. Further improvements include sensor-based positioning, and a receiver having inflow and outflow conduits adapted to improve thermal efficiency.

Abstract: A solar energy module includes a casing, a mirror, a transparent top, a pipe, a fluid within the pipe and photovoltaic cells. The casing has three walls including two end walls and one wall in the form of an elongated U-shaped structure. The mirror is parabolic and sits atop the bottom wall of the casing to produce a line focus within the casing. The transparent top closes the casing to form an air-tight enclosure. The pipe has flat walls and is positioned at the line focus. The flat walls are at least a top-facing planar wall and a bottom-facing planar wall. The photovoltaic cells are attached at least to the bottom-facing planar wall. The fluid is confined within the pipe and carries away the heat from the photovoltaic cells. The air-tight module is optionally holding a vacuum and/or contains inert gas.

Abstract: Systems, methods, and apparatus by which solar energy may be collected to provide electricity, heat, or a combination of heat and electricity are disclosed herein.

Abstract: A solar thermal power plant is provided. The solar thermal power plant includes a thermal-electric power plant and a solar collection system in communication therewith to provide heat thereto for driving its operation and being designed to facilitate capture of thermal energy of incident solar radiation by a thermal transfer fluid flowing therethrough for providing the heat. The solar collection system includes one or more solar collectors configured for the capture. The solar collection system further includes at least one dual-purpose pipe configured for carrying heated thermal transfer fluid to the thermal-electric power plant, the dual-purpose pipe including a supply chamber for carrying the thermal transfer fluid therethrough, and at least one storage element in thermal communication with and in fluid isolation from the supply chamber, and being configured for storing thermal energy for providing heat for driving operation of the thermal-electric power plant.

Abstract: This invention is a trough solar collector that uses inexpensive aluminized plastic films as the reflecting surface. The films are held in proper shape by stretching them between rigid ribs that are spaced apart along the length of the collector. The structure of the trough is held rigid by a unique sun-tracking system that not only guides a whole of array of troughs on a field to point them toward the sun, but also maintains the whole length of each trough in rigid configuration. It is not necessary to extend rigid metal beams along the trough to maintain the rigidity of the trough. Small-diameter cables are wrapped around rotatable pipes that extend along the east and west sides of the field. The cables extend over the field of the troughs and are attached to connecting points above the troughs in such a way that when the rotatable pipes rotate, the cables move, the troughs move with them, and the cables provide the rigidity of the troughs.

Abstract: A solar energy system comprising linearly focusing optical components and at least on receiver. The solar energy system comprises a device for assembling and disassembling the receiver, wherein the receiver (2) is slidably arranged on a longitudinal rail (4), which enables the receiver in its entirety, or in parts to be slid into and moved to a desired position in the solar energy system, or disassembled, respectively.

Abstract: The present application provides a primary reflector in a solar collection system. The primary reflector includes a first reflective section that can reflect solar rays onto a first focal line, a second reflective section on the left side of the first reflective section, and a third reflective section on the right side of the first reflective section. The second reflective section can reflect solar rays to the right side of the first focal line. The third reflective section can reflect solar rays to the left side of the first focal line.

Abstract: A method of wastewater treatment comprises: providing waste water to a vessel within a solar collector; and superheating the waste water under pressure within the vessel using solar energy of the solar collector, thereby to provide oxidation conditions from said solar energy to oxidize organic matter. The water may then be passed to a flash chamber to vaporize and leave behind a brine with dissolved salts.

Abstract: A solar power conversion receiver is described. In one aspect, the solar power conversion receiver includes a circular glass envelope and an absorber tube encapsulated within the circular glass envelope. An annulus, positioned between the circular glass envelope and the outer perimeter of the absorber tube, is bifurcated by first and second fins operatively coupled to the circular glass envelope and the absorber tube. These fins create first and second annulus compartments that are substantially sealed off, or independent, from one another. The first and second fins are ductile and responsive to expansion and contraction of components in the solar power conversion receiver due to temperature effects. In one aspect, gas in the lower annulus compartment stratifies with cooler gas interfacing with the encapsulating glass envelope, and hotter gas interfacing with the hotter absorber tube, resulting reduced natural convection heat loss as compared to conventional glass encapsulated receivers.

Abstract: The fixed focus parabolic trough collector comprises a mirror structure (10) with a plurality of mirror segments (S1, S2, S3, . . . ). At least two adjacent mirror segments (S1, S2) form a gap (14) through which radiation (R3) reflected by a third mirror segment (S3) is incident on the absorber pipe (13) positioned at the focal point of all mirror segments. This minimizes the path of the reflected radiation. The mirror structure has compact dimensions relative to the aperture opening and is minimally affected by wind.

Abstract: Concentrating solar collector systems that utilize a concentrating reflector to direct incident solar radiation to a solar receiver are described. In one aspect, the reflective surface is arranged to direct light to the receiver in a non-imaging manner in which the solar rays reflected from the opposing edges of the reflective surface are generally directed towards a central portion of the solar receiver. Rays reflected from selected central portions of the reflective surface are directed closer to the edges of the receiver than the solar rays reflected from the edges of the reflective surface. The described reflectors are generally intended for use in solar collector systems that track movements of the sun along at least one axis.

Abstract: Solar trough apparatuses are disclosed, where a heat transfer fluid conduit remains fixed in a focal of a solar trough as the solar trough tracks the sun. The support structures can be ring or arcuate structures, where rotation is about their central axis and the trough is support in them so that the focal zone is coincident with the axis of rotation and the conduit is situated in the focal zone eliminating the need for articulated or flexible conduit.

Abstract: A solar trough field system according to the invention comprises multiple parabolic reflectors; a thermal receiver tube, center of which coincides with the focus of the parabolic reflectors and which consists of a metal heat receiving pipe (1) and a glass tube (2) which are nested (the glass tube surrounds the metal heat receiving pipe from outside); a ‘vacuum seal and glass tube connector system’ (E) which connects the glass tubes (2) and the thermal heat receiving pipe (1) to each other; a rotating support unit (21), which connects the parabolic panel to the glass tube connector system (E) and provides the thermal receiver tube (1) to stay stationary while the parabolic panel is rotating around it; ‘flexible expansion unit’ (29) located at the end of each parabolic trough unit which provides vacuum seal while the Heat Receiving Pipe (1) is moving due to heat expansion; and a vertical loop (52) located at the discharge side of the parabolic unit, which can be used instead of water separator and which also pr

Abstract: This invention is a trough solar collector that uses the principles of high leverage in order to produce a lightweight, inexpensive thermal solar collector. The parabolic reflectors are held in proper shape by rigid ribs that are spaced apart along the length of the collector. The structure of the trough is held rigid by a unique sun-tracking system that not only guides a long trough row to point it toward the sun, but also maintains the whole length of the row in rigid configuration. Small-diameter cables are wrapped around a rotatable pipe that extends along the row. The cables extend around circular arches attached to the parabolic ribs that provide high leverage for rotating the troughs. Since the arches rotate in unison, the long trough row is maintained in rotational rigidity. Rather than having heavy concrete foundations and heavy structures to support the troughs, lightweight support posts are placed into the ground, and guy wires maintain the position of the posts.