Abstract: The present disclosure is directed to concentrating sunlight. In some implementations, a concentrator includes a plurality of reflector support structures and a plurality of reflector segments associated with each reflector support structure. Each reflector support structure formed to include a curved surface that receives an associated reflector segment and a bottom portion that distributes the weight of the reflector segment along a surface area. Each reflector segment includes a reflecting surface adjacent a flexible element such that the reflecting surface reflects incident sunlight light. In some examples, the reflector support structures may comprise a light weight material such as a polyurethane and/or the reflecting surface may be 5 mils or less.

Abstract: The present disclosure is directed to generating hydrogen using thermal energy. In some implementations, a method includes concentrating solar energy on an absorption element to heat the absorption element to about 2,000° C. or greater. The absorption element is in thermal contact with a reservoir of water. The water is at a pressure of, for example, approximately 760 Torr or less, and at least a portion of the water disassociates based on heat from the absorption element. The hydrogen and the oxygen are rapidly cooled to substantially avoid recombination. After cooling, the hydrogen gas and oxygen gas are pressurized and then separated using a size-selective membrane.

Abstract: In some implementations, a system for disassociating water includes a decomposition chamber, a heating element, a plurality of hollow fiber membranes, and a water inlet. The heating element is positioned in the decomposition chamber and configured to generate heat sufficient to dissociate at least a portion of water to hydrogen and oxygen. The plurality of hollow fiber membranes include at least a section of each hollow fiber membrane that passes through the decomposition chamber and has an inner conduit and an outer wall. The inner conduit for each hollow fiber membrane is configured to pass a sweep gas, and the outer wall for each hollow fiber membrane is configured to selectively pass either oxygen or hydrogen. The water inlet connected to the decomposition chamber and configured to pass water vapor into the decomposition chamber.

Abstract: The present disclosure is directed to generating hydrogen using thermal energy. In some implementations, a method includes concentrating solar energy on an absorption element to heat the absorption element to about 2,000° C. or greater. The absorption element is in thermal contact with a reservoir of water. The water is at a pressure of, for example, approximately 760 Torr or less, and at least a portion of the water disassociates based on heat from the absorption element. The hydrogen and the oxygen are rapidly cooled to substantially avoid recombination. After cooling, the hydrogen gas and oxygen gas are pressurized and then separated using a size-selective membrane.