Abstract: A solar heat collecting element for use in solar troughs and solar power systems. The solar heat collecting element includes a conduit for carrying a heat transfer fluid; a light transparent envelope disposed about the conduit; and an edge welded metal bellows assembly coupling a first end of the conduit with a first end of the envelope.

Abstract: A solar heat collecting element for use in solar troughs and solar power systems. The solar heat collecting element includes a conduit for carrying a heat transfer fluid; a light transparent envelope disposed about the conduit; and an edge welded metal bellows assembly coupling a first end of the conduit with a first end of the envelope.

Abstract: A solar receiver assembly includes a tube adapted to carry a heat transfer medium and a glass envelope surrounding the tube and having opposed ends. An interface is disposed between each end and the tube so as to seal and support the tube from the envelope. And the receiver includes a prism disposed over the interface to divert incident radiation away from the interface and toward the tube and/or the glass envelope. The prisms may be provided with reflective and/or anti-reflective coatings to further optimize diversion of radiation from the interface.

Abstract: A solar receiver assembly includes a tube adapted to carry a heat transfer medium and a glass envelope surrounding the tube and having opposed ends. An interface is disposed between each end and the tube so as to seal and support the tube from the envelope. And the receiver includes a prism disposed over the interface to divert incident radiation away from the interface and toward the tube and/or the glass envelope. The prisms may be provided with reflective and/or anti-reflective coatings to further optimize diversion of radiation from the interface.

Abstract: A matched glass-to-metal connecting device for use in a vacuum tube collector for a solar energy collecting apparatus is made of a glass envelope and a metal sleeve directly bonded to the glass envelope. The glass envelope is made of a glass having a composition, in percent by weight on the basis of oxide content, consisting essentially of B2O3, 19; Al2O3, 8; Na2O, 2; K2O2, 3; BaO, 3; LiF, 1; and balance of SiO2 and the metal sleeve consists of metal material number 1.3981 of DIN 17745. The glass envelope has a thermal expansion coefficient that deviates from the metal part's thermal expansion coefficient by no more than 4% in the temperature range from 25° C. to 350° C.