A glass tube with a glass tube wall is provided, wherein an inner surface of the glass tube wall comprises at least partially at least one infrared light reflective coating. Additionally a heat receiver tube for absorbing solar energy and for transferring absorbed solar energy to a heat transfer fluid, which can be located inside a core tube of the heat receiver tube, is provided. The core tube comprises a core tube surface with a solar energy absorptive coating for absorbing solar absorption radiation of the sunlight. The core tube surface and an encapsulation are arranged in a distance between the core tube surface and the inner surface of the encapsulation wall with the infrared reflective surface such, that the solar absorption radiation can penetrate the encapsulation with the infrared light reflective coating and can impinge the solar energy absorptive coating.

An inflatable non-imaging solar concentrator water desalination system comprises an inflatable non-imaging stationary solar concentrator and shallow black basin type evaporator. The evaporator is made into a semi-close structure house like a stadium to surround the concentrator. An absorber made of black coating or porous absorption materials is placed on the basin of the concentrator. The evaporator consists of an inner holder, a outer holder, a freshwater collector, and a condenser to form a space for water to evaporate, and to be condensed and collected. The inflatable non-imaging solar concentrator is assembled with the evaporator in such a way that the output aperture of the solar concentrator is directly over the surface of the absorber

An inflatable non-imaging solar concentrator water desalination system comprises an inflatable non-imaging stationary solar concentrator and shallow black basin type evaporator. The evaporator is made into a semi-close structure house like a stadium to surround the concentrator. An absorber made of black coating or porous absorption materials is placed on the basin of the concentrator. The evaporator consists of an inner holder, a outer holder, a freshwater collector, and a condenser to form a space for water to evaporate, and to be condensed and collected. The inflatable non-imaging solar concentrator is assembled with the evaporator in such a way that the output aperture of the solar concentrator is directly over the surface of the absorber

A solar panel (302) for heating a target fluid using incident solar radiation is described, the solar panel (302) includes: three major edges (306) arranged so that the solar panel (302) can be inscribed in a triangle with each major edge (308) of the panel (302) lying along at least a portion of a side of the triangle; a cavity for retaining the target fluid; and an inlet and an outlet for the target fluid, for exchanging the target fluid with adjacent solar panels (302).

A solar panel (302) for heating a target fluid using incident solar radiation is described, the solar panel (302) includes: three major edges (306) arranged so that the solar panel (302) can be inscribed in a triangle with each major edge (308) of the panel (302) lying along at least a portion of a side of the triangle; a cavity for retaining the target fluid; and an inlet and an outlet for the target fluid, for exchanging the target fluid with adjacent solar panels (302).

A glazing unit is provided for producing an aesthetically pleasing effect. The glazing unit may include at least one polymer with a first structured surface to which a photonic structure is applied. The surface can reflect a first partial spectrum of incident electromagnetic radiation, and can transmit a second partial spectrum of incident electromagnetic radiation. A reflected proportion corresponds to a higher harmonic and is in a visible spectral range.

A glazing unit is provided for producing an aesthetically pleasing effect. The glazing unit may include at least one polymer with a first structured surface to which a photonic structure is applied. The surface can reflect a first partial spectrum of incident electromagnetic radiation, and can transmit a second partial spectrum of incident electromagnetic radiation. A reflected proportion corresponds to a higher harmonic and is in a visible spectral range.

A laminated and etched glazing unit having a substrate and a multi-layered interference filter each delimited by two main faces; the incident medium having a refractive index n.sub.inc=1, the substrate having a refractive index n.sub.substrate defined as: 1.45n.sub.substrate1.6 at 550 nm, and the exit medium being defined as follows 1.45n.sub.exit1.6 at 550 nm; and wherein the following requirements are met: The saturation of the colour is higher than 8 at near-normal angle of reflection, except for grey and brown; the visible reflectance is higher than 4%; the variation of the dominant wavelength .sub.MD of the dominant colour M.sub.D of the reflection is smaller than 15 nm for .sub.r<60; and the total hemispherical solar transmittance is above 80%.

A solar window system for a building includes multiple heat generation encasements each including thermoelectric sheets, where the thermoelectric sheets are positioned inside a housing having an interior metal layer. Air inside each heat generation encasement is heated by solar energy. Inside each heat generation encasement, there are pipes filled with Phase-Change Material (PCM) materials that help provide heating to the building. The solar window system further includes a storage tank on top of the system filled with PCM materials for storing heat from the heated air, the storage tank being connected to the pipes of each heat generation encasement. The solar window system includes a set of connection pipes, wherein the set of connection pipes draw cold air from an indoor space inside the building into the plurality of heat generation encasements, connect each of the heat generation encasements to at least two other heat generation encasements, and transfer the heated air from the set of heat generation encasements to the storage tank. The solar window system also includes circular movable rings that can be open and closed as needed. These rings are located around each heat generation encasement and have two movable flexible solar panels capable of generating electricity.

An inflatable light concentrating mirror (10) comprising a first transparent sheet (1) and a second reflective sheet (2), wherein the first sheet and second sheet are connected or sealed to each other, whereby a void is provided there-between, the void being adapted to receive a gas so as to inflate the light concentrating mirror, characterized in that the mirror further comprises tensioning means (14) adapted to produce a defined longitudinal tension (11) in at least the second sheet (2) such that wrinkles or creases therein are significantly reduced. The tensioning means comprises one or more tensioning devices (14) adapted to be attached to at least one mirror end or one free end of the second sheet, the tensioning device is configured to provide a pulling force (11) on the second sheet so as to provide the longitudinal tension.