Photovoltaic thermal (PVT) apparatus 10 combines a photovoltaic panel (PV) panel 24 and solar air heater (SAH). The SAH includes body 12 with hollow interior 14 defining ducts 16a, 18a for air inlet 16 and air return 18. Jets 22 provide air to convey heat from the PV panel underside. Spaces between the jets provide drains 26 for warmed air to flow away. Flow modifiers/deflectors 124 can guide the airflow. A fan 42 pushes ambient air into the inlet 16 via air handling unit (AHU) 50. Return warm air flows via the AHU to escape via the ambient exhaust 40. A combined thermal transfer and storage unit 52 determines whether air from the PVT panel(s) diverts to the interior space. For cooler ambient conditions, the PVT apparatus can radiate heat to return cooled air into the space. The PVT apparatus can harvest condensation, heat/cool pools and industrial processes.

Concentrated solar power and heating systems using solar receivers, and related devices and methods, are generally described.

Concentrated solar power and heating systems using solar receivers, and related devices and methods, are generally described.

The element on which solar radiation is concentrated, specifically, a vacuum tube, remain static at all times with respect to the movements that a parabolic reflective surface may make according to the direction of solar radiation, such that inlet and outlet pipes of the vacuum tube do not need to be articulated, which facilitates the installation and insulation thereof and reduces production costs. The parabolic reflective surface can pivot 360° with respect to the vacuum tube without interfering with the pipes, allowing an active safety system for protecting against strong winds and preventing overheating to be produced, in addition to allowing the surfaces to be cleaned by means of nozzles spray pressurized water. The collector also includes passive safety means against strong winds.

Various implementations include solar thermal energy collection system comprising a solar energy concentrator, a heat transfer fluid, an absorber pipe. The absorber pipe includes a pipe wall and has a central longitudinal axis. The pipe wall has an inner surface and an outer surface. The inner surface has a first contour defining alternating peaks and troughs along a length of the absorber pipe. The outer surface has a second contour defining alternating peaks and troughs along the length of the absorber pipe. The inner surface defines the entire flow path for the heat transfer fluid through the absorber pipe. The first contour, as viewed through an axial cross section of the absorber pipe, forms sinusoidal waves on each side of and spaced apart from the central longitudinal axis. The sinusoidal waves on each side of the central longitudinal axis are symmetrical with respect to the central longitudinal axis.

A roof or wall comprising an insulating selective surface (1) for the use of transferring net heat energy into or out of an enclosure, such as a building. The insulating selective surface comprises at least one transparent cover (2) that comprises a chamber (9), and in the chamber is a moveable plate (4) comprising a plurality of surfaces (5, 6). At least one of the surfaces is a selective surface which can be moved to substantially face the sky, or moved to face away from the sky. The device insulates the enclosure from conductive losses, while using the sun to heat the enclosure, or the cold of deep space to cool the enclosure depending on how the plate is moved.

Systems and methods for radiative cooling and heating are provided. For example, systems for radiative cooling can include a top layer including one or more polymers, where the top layer has high emissivity in at least a portion of the thermal spectrum and an electromagnetic extinction coefficient of approximately zero, absorptivity of approximately zero, and high transmittance in at least a portion of the solar spectrum, and further include a reflective layer including one or more metals, where the reflective layer has high reflectivity in at least a portion of the solar spectrum.

The present invention relates to an automatic motion system by dilatation of a fluid, said system acting on elements of a compact solar collector with integrated storage tank, said solar collector having least a face exposed to the solar radiation and at least another face not facing the solar radiation, said solar collector comprising a plurality of primary tubes, for containing at least one primary heat carrier element adapted to the storage of thermal energy, and an external collector element arranged movable with respect to each primary conduit, adapted to overlap, at least partially, during its motion, in each primary conduit.

A system for energy conversion including photoluminescent (PL) material for absorbing solar radiation and emitting PL radiation, a solar concentrator for concentrating solar radiation on the PL material, photovoltaic (PV) material configured to absorb the PL radiation, and a chamber for containing the PL material and Heat Transfer Fluid (HTF), and further including the system configured to pipe the HTF from the chamber to a system for conversion of HTF heat to energy. Related apparatus and methods are also described.

This invention concerns a receiver unit (10) for a parabolic trough solar plant. The receiver unit (10) has a conduit (12) for conveying a heat transfer fluid (14) and a cover (16), which is located about the conduit (12) such that a vacuum is formed between the conduit and the cover. The conduit (12) is designed to absorb thermal radiation. The cover (16) has a first portion (26) defining a window (22) through which incoming solar radiation (24) passes into the vacuum and onto the conduit (12) and a second portion (28) carrying a reflective surface (20) so as to reflect thermal radiation back onto the conduit (12). The invention also concerns a method of reducing thermal radiation loss from a parabolic trough receiver.