A thermal receiver, such as a solar flux thermal receiver, is disclosed comprising a modular arrangement of arrayed microchannels or micropins to heat a working fluid by heat transfer. Disclosed solar receivers provide a much higher solar flux and consequently a significant reduction in thermal losses, size, and cost, relative to known receivers. Unit cell receivers can be numbered up and combined in parallel to form modules, and modules combined to form full scale receivers.

The invention relates to a receiver (50) having an absorber (55) and an opening (53) for the solar rays incident on the absorber (55) during operation, wherein a window (52, 60, 61, 62) is provided, which covers the opening (53), and wherein a changing assembly (51) is provided, which interacts with said window to change the window (52) covering the opening (53) for another window (60, 61 62).

The invention relates to a receiver (50) having an absorber (55) and an opening (53) for the solar rays incident on the absorber (55) during operation, wherein a window (52, 60, 61, 62) is provided, which covers the opening (53), and wherein a changing assembly (51) is provided, which interacts with said window to change the window (52) covering the opening (53) for another window (60, 61 62).

An absorber system solves problems of known absorber systems for use in solar fields in that the absorber tube is suspended on a rail below an absorber cover. The design also makes it possible to move measuring and cleaning robots and the like along the absorber tube more and allows the absorber tube and the secondary reflector to be jointly suspended, whereby an exact mutual alignment between the two components is enabled.

Methods and systems for separating a first metal from a metal-containing feed stream are provided. The method can include applying solar energy, for example, by focusing one or more mirrors in one or more heliostats, to heat a metal-containing feed stream in a heating zone to a first temperature to produce a first vapor including the first metal. The first vapor can be condensed in a condensation zone to produce a first liquid including the first metal, and the first liquid can be collected. The system can include a separation unit include a heating zone in fluid communication with a condensation zone and a means for applying solar energy to heat a metal-containing feed stream disposed in the heating zone.

Methods and systems for separating a first metal from a metal-containing feed stream are provided. The method can include applying solar energy, for example, by focusing one or more mirrors in one or more heliostats, to heat a metal-containing feed stream in a heating zone to a first temperature to produce a first vapor including the first metal. The first vapor can be condensed in a condensation zone to produce a first liquid including the first metal, and the first liquid can be collected. The system can include a separation unit include a heating zone in fluid communication with a condensation zone and a means for applying solar energy to heat a metal-containing feed stream disposed in the heating zone.

Passive cooling articles may include a first element defining a high absorbance in an atmospheric infrared wavelength range and a high average reflectance in a solar wavelength range. The first element may define a first major surface (114, 214, 314, 414) positioned and shaped to reflect solar energy in the solar wavelength range to an energy absorber (108, 208, 308, 408, 508, 608) spaced a distance from the first major surface (114, 214, 314, 414). The energy absorber (108, 208, 308, 408, 508, 608) may be a heating panel or a photovoltaic cell. A second element may define a high thermal conductivity and thermally coupled to a second major surface (116, 216, 416) of the first element to transfer thermal energy from the second element to the first element to cool the second element.

A mirror includes a carrier, a reflecting layer disposed above a main face of the carrier, and a transparent layer disposed above the reflective layer. The carrier includes a base body, and the base body includes one or more of a material comprising a density in a range from 0.1 to 1.0 g/cm.sup.3, a porous material, a foamed material, a material comprising a structure containing closed cells, a material comprising a honeycomb structure, or a structure containing carbon fibers.

A mirror includes a carrier, a reflecting layer disposed above a main face of the carrier, and a transparent layer disposed above the reflective layer. The carrier includes a base body, and the base body includes one or more of a material comprising a density in a range from 0.1 to 1.0 g/cm.sup.3, a porous material, a foamed material, a material comprising a structure containing closed cells, a material comprising a honeycomb structure, or a structure containing carbon fibers.

The present invention refers to a method for making a reflecting stratiform structure (100), configured so as to reflect the incident radiation coming from an upper side with respect to the reflecting stratiform structure (100), comprising an upper transparent protective coating layer (101) configured in that the upper transparent protective coating layer (101) is applied to the reflecting stratiform structure (100) through a cross-linking process, which is carried out by cross-linking a polymerisable resin, which will form the upper transparent protective coating layer (101), making energy pass through a transparent thermoplastic film (102, 120), preferably made of polyethylene terephthalate (PET), so as to cross-link the polymerisable resin.