Linear Fresnel lenses, their design and use

A linear Fresnel lens (LFL) designed according to Fermat's principle is slightly modified with respect to used technology for mass production from glass. Manufactured Fresnel lenses are used in a fully tracking concentrating collector with aperture about 36 m² and in a collector with stationary concentrator and movable absorber, which may serve as solar collector with temperature and illumination control. A combination of linear Fresnel lenses with PV cells may reduce cost of autonomous solar installations.