High-concentration collection and remote delivery of sunlight with fiber-optic mini-dishes

A new approach to the efficient collection and remote delivery of concentrated solar energy is proposed. The system's building block is a miniature (e.g., 0.2 m diameter) dish which concentrates sunlight into a single optical fiber. A number of mini-dishes comprise a module from which the optical fibers transport bundled power to a remote receiver. A second-stage nonimaging concentrator can boost flux levels to those approaching the thermodynamic limit and can be performed either in each individual dish or collectively in one or more larger devices at the entrance to the remote receiver. There are substantial advantages in efficiency, compactness, reduced mechanical loads, and ease of fabrication and installation relative to conventional solar designs. The design exploits the availability of low-attenuation optical fibers of high numerical aperture, as well as the practical advantages of mass producing highly accurate very small parabolic dishes. Designs for maximum efficiency attaining collection efficiencies as high as 80%, and maximum-concentration designs realizing flux levels of 30,000 suns, are achievable.