The present invention provides an apparatus for heating a fluid using solar energy. The apparatus comprises: a fluid source, a first chamber comprising a fluid inlet to allow one-way movement of a fluid from the fluid source to the first chamber, a second chamber comprising a fluid outlet to allow the controlled movement of a fluid internal the second chamber to a further chamber or external the apparatus, and a fluid connection between the first and second chambers to allow substantially one-way movement of a fluid from the first chamber to the second chamber. Each of the chambers is fluid tight and configured as a solar collector to heat a fluid therein. The apparatus as a whole operates such that under even incident solar radiation a fluid is heated in each of the chambers and upon thermal expansion of the fluid, the fluid is moved in a controlled manner substantially one-way from the first chamber to the second chamber, and from the second chamber to a further chamber or to the outside the apparatus. By the movement of fluid from the first chamber to the second chamber, the first chamber donates a portion of the heat energy held by the fluid therein to the second chamber, the second chamber becomes enriched in heat energy by the gain of fluid and the first chamber becomes deprived in energy by the loss of fluid such that the second chamber contains fluid that is hotter than the first chamber.

The invention provides in some aspects a thermal energy collection system comprising a first solar collector through which a first heat transfer fluid flows to absorb energy from sunlight as it passes through the first solar collector, and a second solar collector that collects energy from sunlight that has passed through the first solar collector. The first heat transfer fluid of the thermal energy collection system according to these aspects of the invention is in thermal coupling with the first solar collector, but not with the second solar collector. In other aspects, the invention provides a radiator system, comprising a multi-wall panel, an interior of which is in fluid coupling with, and that forms part of, a fluid circuit through which a first heat transfer fluid flows. A reflective surface is disposed in a vicinity of a second face of the multi-wall panel. Still other aspects of the invention provide a reflective film solar energy collector and a solar energy absorber.

The invention provides in some aspects a thermal energy collection system comprising a first solar collector through which a first heat transfer fluid flows to absorb energy from sunlight as it passes through the first solar collector, and a second solar collector that collects energy from sunlight that has passed through the first solar collector. The first heat transfer fluid of the thermal energy collection system according to these aspects of the invention is in thermal coupling with the first solar collector, but not with the second solar collector. In other aspects, the invention provides a radiator system, comprising a multi-wall panel, an interior of which is in fluid coupling with, and that forms part of, a fluid circuit through which a first heat transfer fluid flows. A reflective surface is disposed in a vicinity of a second face of the multi-wall panel. Still other aspects of the invention provide a reflective film solar energy collector and a solar energy absorber.

A heat transfer device (100) includes an inner tube (102) mounted within a tubular chamber (104) of a heat exchanger (106). The hollow tubular chamber (104) has a closed end (108) with inwardly sloping inner surfaces (110) and the inner tube (102) has an open end (112) that terminates short of the closed end (108). A diffuser (114) is provided and is shaped such that an operatively front part (116) thereof substantially conforms to a shape of the inner surfaces (110) of the closed end (108) so as to form a narrow flow passageway (118) between the diffuser (114) and the inner surfaces (110) at the closed end (108), and an operatively back part (120) of the diffuser (114) slopes towards the inner tube (102) and away from its open end (112) to form a diffusion zone (122). Heat transfer assemblies utilising the heat transfer device (100) are also disclosed.

The invention relates to a method for producing syngas by means of solar radiation, in which the reactor of a receiver-reactor is periodically heated via an aperture provided in the same for solar radiation by means of the solar radiation to an upper reduction temperature for a reduction process and subsequently cooled to a lower oxidation temperature for an oxidation process in the presence of an oxidation gas, wherein the sunlight is guided through an absorption chamber onto an absorber configured as a reactor, which includes a reducible/oxidizable material, and wherein a gas that absorbs the black-body radiation of the absorber is guided through the absorption chamber and the absorption chamber is configured so that the back radiation of the absorber through the aperture is essentially absorbed by the gas. Radiation losses caused by back radiation of the black-body radiation exiting the optical aperture are thus avoided in accordance with the invention. The heat of the back radiation, however, can be utilized directly in the heat-transporting fluid and is available for a flexible usage. The receiver-reactor has a simple design and is suitable as a low-cost receiver-reactor.

This invention provides a solar heat-collecting pipe that includes, in the stated order from the inner side on the outer surface of a ferrous material pipe through the interior of which a heat transfer medium is allowed to flow, at least a first diffusion-preventing layer, a second diffusion-preventing layer, an infrared radiation-reflecting layer, a sunlight-to-heat conversion layer and an anti-reflection layer. The first diffusion-preventing layer includes at least one selected from the group consisting of silicon oxide, aluminum oxide and chromium oxide. The second diffusion-preventing layer includes at least one selected from the group consisting of tantalum nitride, tantalum oxynitride, titanium nitride, titanium oxynitride, niobium nitride, and niobium oxynitride.

This invention provides a solar heat-collecting pipe that includes, in the stated order from the inner side on the outer surface of a ferrous material pipe through the interior of which a heat transfer medium is allowed to flow, at least a first diffusion-preventing layer, a second diffusion-preventing layer, an infrared radiation-reflecting layer, a sunlight-to-heat conversion layer and an anti-reflection layer. The first diffusion-preventing layer includes at least one selected from the group consisting of silicon oxide, aluminum oxide and chromium oxide. The second diffusion-preventing layer includes at least one selected from the group consisting of tantalum nitride, tantalum oxynitride, titanium nitride, titanium oxynitride, niobium nitride, and niobium oxynitride.

A solar heat collector tube in which at least an infrared reflective layer, a sunlight-heat conversion layer and an anti-reflection layer are provided on the outer surface of a tube, through the interior of which a heat medium can flow, wherein the infrared reflective layer in the solar heat collector tube has a multilayer structure in which an Ag layer, having dispersed therein at least one metal selected from the group consisting of Mo, W, Ta, Nb and Al, is sandwiched between two metal protective layers.

A solar heat collector tube in which at least an infrared reflective layer, a sunlight-heat conversion layer and an anti-reflection layer are provided on the outer surface of a tube, through the interior of which a heat medium can flow, wherein the infrared reflective layer in the solar heat collector tube has a multilayer structure in which an Ag layer, having dispersed therein at least one metal selected from the group consisting of Mo, W, Ta, Nb and Al, is sandwiched between two metal protective layers.

A cladding panel that collects and/or emits thermal energy, which includes: a first panel; a second panel with an extrados adhered to an intrados of the first panel, forming a leaktight seal, with a low-relief channel, the channel being attached to the intrados of the first panel to form a conduit; an inlet connector for heat-conducting fluid, connected to a first end of the channel; and an outlet connector for heat-conducting fluid, connected to a second end of the channel, wherein the first panel is made of calibrated laminated ceramic with a flat, smooth intrados and a flat, smooth extrados and has a uniform thickness of 3-6 mm, and the second panel is made of waterproof heat-insulating plastic that is stable up to 120 C.