New Solar Air Heater Based on Non-Imaging Optics for High-Temperature Applications

A novel solar air heater is presented, that allows for temperatures exceeding 100° C with thermal efficiencies of over 50%, due to a non-imaging solar concentrator and the reduction of thermal losses from the air circulating between the absorber and mirrors with a circular cross-section, which are well insulated from the outside surroundings. The receiver consists of a concentrator with transparent prisms that function as lenses. The rays of light refracted by the prisms enter a series of CPC concentrators, which have been optimally truncated so that the space between them allows for the positioning of the absorber, which consists of a series of metallic segments covered with a selective film. Its excellent performance makes it ideal for applications such as Sauna baths, drying processes at high temperatures, and air conditioning systems.