Abstract: A solar thermal assisted water heating system includes a thermal collector comprising a plurality of fluid channels configured to collect heat from a surface of a photovoltaic module, a drain-back tank coupled to the thermal collector, a first pump coupled to the drain-back tank and configured to pump fluid from the drain-back tank to the thermal collector, a first heat exchanger configured to receive fluid from the thermal collector, a heat pump coupled to the first heat exchanger and configured to remove heat from the fluid and heat water with the removed heat, and a controller configured to control the first pump and heat pump. The system may include a photovoltaic module and a hot water tank. These systems improve the efficiency of water heating, and the drain-back tank may serve as a thermal battery that stores heat and provides the stored heat when environmental temperatures decrease.

Abstract: A heat collector device is provided. The heat collector includes an exterior surface exposed to an environment, and an interior surface. Side walls separate the exterior and interior surfaces. A heat insulation interposes the exterior and interior surfaces. Each hot air duct includes a first portion interfacing with the external surface and a second portion interfacing with the heat insulation. Each cold air duct is encompassed by the heat insulation. A first chamber formed by a first side wall provides fluidic communication between the air ducts at a first end portion of each respective duct. A second chamber formed by a second side wall provides fluidic communication between the air ducts at a second end portion of each respective duct. A heat exchange mechanism disposed in the second chamber removes heat from a first fluidic medium of the air ducts, the first chamber, and the second chamber.

Abstract: A heat storage and heat release system for molten salt with steam heating is provided. The heat storage and heat release system for molten salt with steam heating includes a low-temperature molten salt tank, a high-temperature molten salt tank, molten salt pumps, a boiler barrel, a fixed tube-plate heat exchanger and a drum. The boiler barrel, the fixed tube-plate heat exchanger and the drum are arranged from high to low and are respectively. At least one molten salt outlet pipe and at least one molten salt returning pipe from the low-temperature molten salt tank are connected with the tube pass of the fixed tube-plate heat exchanger. At least one molten salt outlet pipe and at least one molten salt returning pipe from the high-temperature molten salt tank are connected with the tube pass of the fixed tube-plate heat exchanger.

Abstract: A solar collector is provided. The collector comprises a monolithic flow control component to direct a flow of the heat transfer fluid between an inlet and outlet; and a solar absorber supported by the monolithic flow control component. The monolithic flow control component is able to support the solar absorber without any additional structural components to lend mechanical strength to the monolithic flow control component.

Abstract: A method and apparatus for storing thermal energy by flowing a heat transfer medium horizontally over and between a plurality of relatively thin concrete plates in parallel flow paths.

Abstract: The present disclosure is directed to multi-stage falling particle receivers and methods of falling particle heating. As the particles fall through the receiver, the particles are periodically collected and released by flow retarding devices. The periodic catch-and-release of the particles falling through the receiver reduces particle flow dispersion, increases particle opacity and solar absorption, and reduces erosion and damage to surfaces caused by direct particle impingement.

Abstract: An integral collector storage solar water heat collecting apparatus comprises an integral solar heat collecting and storage apparatus having one or more solar ray and ambient temperature heat absorbing and storage material(s) which hold said energy within an enclosure, said enclosure having within it one or more heat exchange coils with pressurized water to be heated for the end-user or client from said heat storage. Said heat collector is combined with other system components to provide heated water to users.

Abstract: A hybrid solar system including a hybrid solar collector using non-imaging optics and photovoltaic components and a heat transfer and storage system in thermal communication with the hybrid solar collector, the heat transfer and storage system using particle laden gas as thermal media to simultaneously generate and store electricity and high temperature dispatchable heat.

Abstract: The invention discloses an efficient solar flat plate heat absorption system, composed of a primary circulating pipe network, a secondary circulating pipe network and a control system, wherein the primary circulating pipe network is formed by communicating a pipeline in a pressure bearing water tank with a heat exchange tube I in a flat plate heat collector group through a pipeline I and a pipeline III, the secondary circulating pipe network is formed by communicating a pipe network at the bottom of a swimming pool with a heat exchange tube II in the flat plate heat collector group through a pipeline II and a pipeline IV, wherein thermometers are arranged at a water outlet of the heat exchange tube I, at the water outlet of the heat exchange tube II, in the swimming pool and in the pressure bearing water tank, and circulating pumps are arranged on the pipeline I and the pipeline II.

Abstract: The invention, in some embodiments, relates to solar energy collectors, and methods of use thereof. In some embodiments, the invention relates to liquid-air transpired solar energy collectors, and methods of use thereof. In some embodiments, the invention relates to thermal energy transfer systems that comprise solar energy collectors, and methods of use thereof. In some embodiments of the invention, methods of constructing solar energy collectors are provided.

Abstract: A warewash machine includes a sump for collecting hot cleaning water that is recirculated in the chamber during cleaning, a drain path for draining cleaning water from the sump and a fresh water input line including at least a fresh water input that receives fresh water. A waste water heat recovery arrangement includes a plurality of heat exchange compartments arranged in series flow communication and forming part of the drain path. A waste water input is associated with a first of the heat exchange compartments and a waste water output associated with a last of the heat exchange compartments. Waste water at least partially fills each of the heat exchange compartments. At least part of the fresh water input line passes through each of the heat exchange compartments. Heat from waste water is transferred to fresh water in the drain line within each heat exchange compartment.

Abstract: A solar collector has an opaque cover heated by solar energy. Heat flows from the opaque cover by conduction, convection, and infrared emittance across a gap within an at least substantially airtight enclosure to an absorber containing a working fluid. The exterior surface of the opaque cover has high solar energy absorptance and the interior surface has high infrared emittance. The exterior surface preferably has low infrared emittance. In one embodiment, fully wetted surface geometry permits direct and reflected infrared absorption by the absorber. The opaque cover eliminates the weight, cost and other shortcomings of glass. A hollow continuous side wall with rounded corners provides an embodiment that is robust yet economical, that is easy to manufacture and seal, that permits a reduced thickness of the opaque cover and mitigates the destructive potential of severe winds, and that can withstand the compressive forces experienced by an evacuated solar collector.

Abstract: In one embodiment a solar collector is provided. The collector has a modular heat transfer component, which includes a heat transfer core to heat up a heat transfer fluid in the form of an aerogel. The heat transfer core positioned comprises a light absorption element, and a fluid transfer element in the form of an aerogel. The aero gel comprises voids shaped and dimensioned to support passive pumping of the heat transfer fluid therethrough.

Abstract: A density engine includes an object movably positioned in a host liquid, the object having a density less than that of host liquid. An injector injects gas below the object creating a rising fluid region having a density less than that of the object. The object is not buoyant in the rising fluid region. An electrical generator is coupled to the object to generate electrical energy upon movement of the object. A biofuel production facility receives gas from the density engine and produces a biofuel through a biological process of a living organism that utilizes the gas. A consolidated energy production and storage system includes a gas sequestration facility, a density engine, and a biofuel production facility located together on a contiguous plot of land. Windmills and solar collectors may be located on the plot of land.

Abstract: The present disclosure provides a system and method for generating power, such as electrical power, using an increased volume of a working liquid in a tank when the working liquid is heated. The increased volume of the working liquid may increase a pressure in the tank such that a portion of the working liquid is forced through one or more fluid lines towards a hydraulic generator. The hydraulic generator may then generate electricity based at least in part on the portion of fluid transferred to the hydraulic lines.

Abstract: In one embodiment a solar collector is provided. The collector has a modular heat transfer component, which includes a heat transfer core to heat up a heat transfer fluid. The collector makes use of the heat transfer fluid itself to prevent heat loss through radiation.

Abstract: The present invention relates to a dual-passage open-type solar heat absorber having a porous plate array, and more particularly, to a dual-passage open-type solar heat absorber which is formed in a form of a rectangular-shaped container in order to increase a contact area with collected sunlight and easily extend in a lateral direction or in a form of a circular-shaped container which is advantageous when a pressure is applied thereto, and which includes a main body formed in a formed of a rectangular or circular-shaped container by using a three-layered tube to form a dual passage therein so that heat is prevented from being lost through an outer wall.

Abstract: In one embodiment a solar collector is provided. The collector has a modular heat transfer component, which includes a heat transfer core to heat up a heat transfer fluid. The collector makes use of the heat transfer fluid itself to prevent heat loss through radiation.

Abstract: A novel heat exchange device to provide sufficient amounts of heat within a manifold including a working fluid within heating coils to generate electricity through an external combustion steam engine and electrical generator is provided. Such a novel heat exchanger includes coils that surround a central heating compartment thereby exposing such coils to gradually increasing temperatures such that the working fluid is first vaporized and then is ultimately superheated to a “dry” steam upon the point of egress of the heat exchanger leading to the engine portion. In this manner, greater efficiency in heating of the working fluid is accomplished with all of the fluid converted to a gas under pressure to effectuate the necessary engine, etc., movement for energy production.

Abstract: A solar water heater has a main panel having a boiler panel and a reservoir panel. The reservoir panel feeds the boiler panel. A tubular reservoir is installed in the reservoir panel. An evacuated tube is installed in the boiler panel. The evacuated tube has an inner vacuum wall and an outer vacuum wall for insulating the evacuated tube. A boiler line receives heated water from the reservoir panel. The boiler line passes through the evacuated tube. An electrical production module is connected to the boiler panel. The electrical production module generates electricity from steam power taken from the boiler panel. A feed line connects to the reservoir panel. The feed line ends at an intake filter.

Abstract: Described is a pipeline system for conveying a salt melt, comprising at least one pipeline (5) through which the salt melt flows, at least one inlet and at least one outlet, wherein the pipeline (5) through which the salt melt flows has at least one gradient inclined with respect to the horizontal and is respectively connected at the lowest positions via a drainage valve (25) to a drainage line (27) and at the highest positions to a venting valve (23). Also described is a method for draining the pipeline system.

Abstract: Insulated solar panels that provide a solar thermal collector with means for limiting stagnation temperatures and preventing damage include: temperature limiting is provided by the insulated solar panel, isolating internal components from the environment, using passive closed systems within the sealed solar thermal collector, while also allowing alternative implementations as active systems and/or portions of the temperature limiting system outside the sealed solar thermal collector. A heat pipe can be used as a passive thermal switch, where the temperature induced action at a predetermined temperature causes an abrupt transition from a state of thermal isolation to a state of strong thermal coupling. Additionally, a set of siphon circulation pipes provides a passive closed system for temperature limiting.

Abstract: Towards recovering thermal energy, an accumulator buffers a working fluid over an energy recovery cycle that includes two processes: one in which working fluid is accumulated in the accumulator at increasing pressure and the other that draws working fluid from the accumulator at decreasing pressure. Heat storage fluid is displaced in a storage fluid conduit towards a heat storage region in response to increasing pressure in the accumulator and towards a reservoir region in response to decreasing pressure in the accumulator. One or more heat exchange conduits traverse the storage fluid conduit to come in thermal contact with the heat storage fluid where they transfer heat to the heat storage fluid during the first process of the energy recovery cycle and transfer heat from the heat storage fluid during the other process.

Abstract: An auxiliary steam supply system in a solar power plant includes a solar receiver having a superheater section, a turbine, a steam circuit, a thermal energy storage arrangement and an auxiliary steam circuit. The thermal energy storage arrangement, including a thermal energy storage medium, is configured for the steam circuit to receive a portion of the steam to heat the thermal energy storage medium. The thermal energy storage arrangement may receive the steam from any location across the superheater section. Moreover, the auxiliary steam circuit generating auxiliary steam flow, which thermally communicates with the thermal energy storage arrangement to be heated, is introduced to any location across the superheater section. Capacity of the thermal energy storage arrangement may be relatively small as compared to the solar receiver and may be compact for placement on top of a tower.

Abstract: A solar receiver includes a multi-sided central assembly with wing assemblies extending from corners thereof. The central assembly includes one-sided heat absorption panels, while the wing assemblies use two-sided heat absorption panels. Stiffener structures run across the exposed faces of the various heat absorption panels.

Abstract: The present invention relates to a heating arrangement for heating a fluid, comprising a first heat exchanger loop (5), arranged to act on a fluid to be heated, and a second heat exchanger loop (8), arranged to also act on said fluid to be heated, wherein said second heat exchanger loop (8) is connected to a panel (4) that serves as a solar collector and that is arranged to heat at least a part of said second heat exchanger loop (8).

Abstract: A solar energy receiver comprises a panel, having a graphite core, a substantially gas tight housing encasing the graphite core, a heat exchanger comprising heat exchanger tubing, a heat exchanger inlet and a heat exchanger outlet. The heat exchanger tubing is at least partially embedded in the graphite core, and the heat exchanger inlet and the heat exchanger outlet extend through the housing. The housing is sealed around the heat exchanger inlet and the heat exchanger outlet. A method of manufacturing a solar energy receiver comprises: a) fabricating the heat exchanger in a serpentine coil shape; b) inserting grooved planks of graphite between individual coils of the heat exchanger to form the graphite core such that the coils are encompassed in the grooves; c) inserting the graphite and heat exchanger into the housing; and d) sealing the housing and sealing openings around the inlet and outlet where they pass through the housing.

Abstract: A heat exchanging structure of a solar heat exchanger 3 includes a housing 5 and a pipe 11. The solar heat exchanger includes a heat-resistant container 8 having an open top and containing a low-melting-point metal 9 and a light receiving plate 10. The housing accommodates the solar heat exchanger. The pipe passes a heat carrier H. The pipe is arranged in a space between the housing and the solar heat exchanger in such a way as not to touch the solar heat exchanger. The heat carrier is surely heated by radiant heat from the solar heat exchanger that is heated to very high temperatures. The light receiving plate has a container-like shape having an open top, and therefore, has a large light receiving area to heat itself to higher temperatures compared with a flat light receiving plate.

Abstract: A solar energy collecting system comprises a manifold defining a closed fluid passage between a condensation point and a heating point. The manifold includes a plurality of heat exchange members configured to be in heat exchange relationship with the fluid passage at the heating point, and a heat sink at the condensation point. A plurality of solar energy collector members extend from and operably connect to the heat exchange members of the manifold. The solar energy collector members collect solar energy and transform it into heat energy. Heat energy is transferred from the solar energy collector members to the heat exchange members and to a fluid in the passage in the manifold at the heating point so as to heat the fluid into a vapor. The fluid is circulated in heat exchange relationship to the condensation point where heat energy is transferred to the heat sink so as to cool the fluid to a liquid.

Abstract: A heat pipe comprises an evaporator section 5 having a radiation absorbing plate 6 a portion of an elongate tube 7, and a condenser section 10 at a distal end of the elongate tube 7 remote from the evaporator section 5. A flow control valve 20 is provided between the evaporator section 5 and the condenser section 10 to selectively interrupt communication between said sections when the temperature within the condenser section 10 exceeds a predetermined maximum. A temperature sensitive member, (coil of memory metal 34?, or discs 34?) acts between a support plate 26 and a seat 36 located on a valve pintle 30 to urge the valve head 22 towards the valve seat 24 when the temperature of the temperature sensitive member 34 exceeds a predetermined limit. A return spring 38 is provided to bias the valve head 22 away from the valve seat 24.

Abstract: Insulated solar panels provide that provide a solar thermal collector with means for limiting stagnation temperatures and preventing damage include: temperature limiting is provided by the insulated solar panel, isolating internal components from the environment, using passive closed systems within the sealed solar thermal collector, while also allowing alternative implementations as active systems and/or portions of the temperature limiting system outside the sealed solar thermal collector. A heat pipe can be used as a passive thermal switch, where the temperature induced action at a predetermined temperature causes an abrupt transition from a state of thermal isolation to a state of strong thermal coupling. Additionally, a set of siphon circulation pipes provides a passive closed system for temperature limiting.

Abstract: A solar water heating system, including: (a) a solar heating collector, having: (i) an array of convex lenses; (ii) a panel disposed below the array of convex lenses, wherein the array of convex lenses focuses sunlight on the panel to heat areas of the panel; (iii) a fluid chamber disposed below the panel; and (iv) a plurality of members extending from the panel into the fluid chamber to transfer heat from the panel into fluid in the fluid chamber; (b) a fluid reservoir; (c) a fluid inlet line for moving fluid from the fluid reservoir into the fluid inlet of the solar heating collector; (d) fluid outlet line for moving fluid from the fluid chamber of the solar heating collector to the fluid reservoir; and (e) a pump for moving fluid cyclically through the fluid chamber of the solar collector and the fluid reservoir.

Abstract: A thermal energy storage system includes fluid conduits disposed in a loose solid material. The loose solid material may be disposed inside a waterproof barrier, and the fluid conduits may be configured to define a plurality of zones having different temperatures in operation. The system may include a solar collector or other source of heated oil or other fluid that is routed to the thermal energy storage unit and/or an energy-consuming facility.

Abstract: A solar hot water and recovery system includes a water loop, a refrigerant loop and a solar loop. Cross-heat exchange occurs in a first heat exchanger between the heat transfer mediums of the refrigerant loop and the solar loop to produce a super-heated fluid stream which is returned to the air conditioning or heat pump unit. Cross-heat exchange also takes place in a second heat exchanger between the now-lower temperature heat transfer medium of the solar loop and the water loop to produce a heated water stream. The main objective of the system is to superheat refrigerant and use all excess heat for heating the water. The heat exchangers are preferably housed in the same heat recovery unit and arranged so that the refrigerant heat exchange area is before the water heat exchange area, thereby maximizing solar potential.

Abstract: A hot water feeder in which a solar heat collector is used. The feeder has a first heat exchanger for heating a heat medium by solar heat, a second heat exchanger for heating water in a hot-water tank by the heated heat medium, and a heat exchange volume determination unit. The heat exchange volume determination unit calculates the flow rate of the heat medium circulating between the first and second heat exchangers on the basis of the detected temperature of the heat medium fed to the first heat exchanger and the rotational speed of a heat medium circulation pump, and calculates the heat exchange volume on basis of the flow rate and the temperature difference between the detected temperatures.

Abstract: A device for using solar energy to heat air. The device can include a hot air panel having a box. The box can include a glazing, a collection plate, and a base layer. The collection plate can be disposed between the glazing and the base layer so as to define a first chamber and a second chamber. The first chamber can be an insulation chamber that can hold air within the box. The second chamber can be a flow chamber that allows air to flow through the box. The box can be further associated with a temperature detection device and a fan.

Abstract: A thermal storage and transfer method for use in both indirect and direct heating solar power plants that involves the use of nitrogen gas as a thermal storage medium for heat transfer in circumstances where little or no solar radiation is available to produce the thermal energy needed to convert water into steam and generate electricity.

Abstract: A method and a control system for a hot water supply system, wherein the hot water supply system includes at least one boiler having a heating fluid input pipe line, the control system comprising: a motorized valve; installed upon the heating fluid input pipe line; a first thermistor installed upon the heating fluid input pipe line; a second thermistor installed within the boiler; a motor mechanically connected to the motorized valve; and a controller, wherein the controller is adapted for opening and closing the motorized valve according to temperature difference between a temperature measurement by the first thermistor and a temperature measurement by the second thermistor, wherein the controller is electrically connected to the motor, to the first thermistor, and to the second thermistor.

Abstract: A thermoregulation apparatus for a solar thermal energy capture system comprising a piping infrastructure in fluid communication with a fluid storage tank and one or more solar thermal energy collectors. The thermoregulation apparatus comprises: (i) a thermostatically actuated valve interposed the piping infrastructure downstream from the one or more solar energy collectors and upstream from the fluid storage tank, and (ii) piping for interconnecting the thermostatically actuated valve with the piping infrastructure, and the fluid storage tank. The thermostatically actuated valve can be configured for diverting the flow of working fluid away from the fluid storage tank when the temperature of the working fluid is below a selected set point for actuating the valve, and for diverting the flow of working fluid to the fluid storage tank when the temperature of the working fluid is about or greater than the selected set point.

Abstract: A thermal storage system 1 includes: heat transfer medium that absorbs the solar thermal energy; phase-change material 10a6 that is heat exchanged with the heat transfer medium; and first thermal storage tanks (stratified tanks 10a-10c) in which the phase-change material 10a6 is supported and through which the heat transfer medium flows, wherein a plurality of the first thermal storage tanks (stratified tanks 10a-10c) are present, and the first thermal storage tanks (stratified tanks 10a-10c) are connected in parallel for the heat transfer medium flowing through, when storing the solar thermal energy, while the first thermal storage tanks (stratified tanks 10a-10c) are connected in series for the heat transfer medium flowing through, when exploiting the stored solar thermal energy. The thermal storage system is capable of exploiting the solar thermal energy more efficiently than conventional ones, while considering a variation in the amount of solar thermal energy.

Abstract: Embodiments provide a solar thermal receiver comprising: (a) a first containing member transparent to sunlight; (b) a second containing member comprising an inner surface reflective of sunlight; (c) an inlet proximate to the first containing member that is configured to receive injected heat transfer fluid; and (d) an outlet distal from the first containing member, where the first containing member and the second containing member together form a vessel configured to conduct injected heat transfer fluid from the inlet to the outlet under hydrostatic pressure.

Abstract: A solar power system having a heat exchanger, a heat-focusing device used to receive sunlight, a power-generating device, a power-transforming device coupled to the power-generating device, and a power storage coupled to the power-transforming device is provided. The heat exchanger has a first guiding channel for a first heat-exchange fluid and a second guiding channel for a second heat-exchange fluid. Sunlight is focused to the first heat-exchange fluid flow in the first guiding channel by the heat-focusing device. One end of the power-generating device is communicated with the outlet of the second guiding channel, and the second heat-exchange fluid is suitable for driving the power-generating device to produce a mechanical energy. The power-transforming device is suitable for transforming the mechanical energy into an electric power and storing the electric power into the power storage.

Abstract: A receiver system for harnessing solar radiation. Embodiments of a receiver system include a receiver including one or more receiver elements, each receiver element including: a plurality of transparent tubes including a first tube and at least one second tube at least partially within the first tube; a first passage interposed between the first tube and the at least one second tube, the first passage having an inlet and an outlet; a second passage within the at least one second tube, the second passage having an inlet and an outlet; and an absorber in the at least one second tube, the absorber adapted to absorb the solar radiation. In some embodiments, a receiver further includes a housing having at least one transparent portion, the housing configured to enclose the plurality of receiver elements, whereby a third passage is formed between the first tube and the housing.

Abstract: A drainback tank having a solar return pipe, at least a portion of the solar return pipe being located within the internal body of the tank, the solar return pipe having a hole that is in close proximity to the hole of an output pipe, such that the fluid in the solar return pipe flows into the output pipe and leaves the tank housing to be used to heat the fluid of a corresponding hot water tank via convection in a heat exchanger.

Abstract: Systems, apparatus, devices and methods of using and mounting solar collectors and photovoltaic collectors in gutters or directly along fascia and eaves and on architectural ledges on buildings, along building walls at various heights above the ground, as well as in ground engaged collectors for providing heated water, power and/or lighting. The collectors can have a pair of conduits/tubes for passing water therethrough. Each of the collectors can be attached to one another by mateably interlocking male and female connectors on the sides of each collector to one another.

Abstract: A steam generation system of an embodiment has a first to fourth heating units. The first heating unit heats a first heat medium by collected solar heat. The second heating unit heats a second heat medium different from the first heat medium by the collected solar heat. The third heating unit heats water or steam by heat of the heated second heat medium. The fourth heating unit further heats the heated water or steam by heat of the heated first heat medium so as to generate steam which is further increased in temperature.

Abstract: The disclosed solar power system includes an oil circuit, a molten salt circuit, and a heat exchanger in communication with both the oil and molten salt circuits. The disclosed heat exchanger includes at least one heat pipe, the ends of which are within first and second plenums provided by spaced-apart housings.

Abstract: The present invention provides a process for absorbing solar energy and, simultaneously having a continuous control of the light admission making it possible to install the device in external openings of buildings and equipment, such as windows, shutters or skylights. The system comprises two frames which support plates of transparent material, between which it is possible to introduce a colourful solution coming from an external reservoir. Both frames are interconnected through a flexible membrane which allows the plates to be pushed against each other, making the window transparent, or pushed away interposing the colourful solution, which will make the window uniform and gradually translucent or opaque. The said liquid comes from a reservoir and the access to the gap between the plates through is obtained by means of a channel that separates the two frames, allowing the liquid to flow evenly into the whole surface, thus being a homogenous and adjustable darkening obtainable.

Abstract: The invention relates to a solar collector (1) comprising a collector housing (2), an absorber (3) arranged therein and having a heating medium fluid (13) flowing through it, to absorb solar radiation (28), a return line (6) leading to the absorber (3) and a flow line (7) leading away from the absorber (3). Thereby a pump (14) is arranged on or at least partially inside the collector housing (2) for circulating a heating medium fluid (13) through the absorber (3).

Abstract: A solar power system, comprising a solar receiver that absorbs solar radiation, at least first and second fluid flow paths passing through the receiver, a first working fluid flowable through the first fluid flow path to absorb thermal energy from the receiver up to a first maximum temperature and a second working fluid flowable through the second fluid path to absorb thermal energy from the receiver up to a second maximum temperature.