Energy collection efficiency of holographic planar solar concentrators

Abstract

We analyze the energy collection properties of holographic planar concentrator systems. The effects of solar variation on daily and annual energy collection are evaluated. Hologram diffraction efficiency, polarization, crosstalk in cascaded elements, and constraints imposed by the radiance theorem, as well as solar illumination characteristics, are considered. A planar holographic solar concentrator configuration is designed and modeled to maximize energy collection efficiency during the course of a year without the need for tracking. Results indicated that nearly 50% of the available energy illuminating hologram areas can be collected by photovoltaic cells without the need of tracking.

Progress in phosphors and filters for luminescent solar concentrators

“…Such devices are attractive, since they are inexpensive and thin and can be easily integrated in appliances. There are several ways to couple sunlight into a light guide [1]: non-luminescent (scattering, refraction or diffraction [2]) and luminescent. Non-luminescent concentrators suffer from limitations given by conservation of étendue [3].…”

Diffractive flat panel solar concentrators of a novel design

“…Inevitably, TIR leads to multiple encounters with the grating [5]. However, by using a properly shaped light guide it is possible to limit the losses that result from these re-encounters.…”

“…Alternatively, the use of diffractive optics has been proposed to design concentrators with a low concentration ratio, but which have the additional benefits of being inexpensive, compact and lightweight [4][5][6][7][8]. A possible concept is to couple sunlight into a light guide using a diffraction grating and subsequently guide it towards a solar cell via total internal reflection (TIR).…”

Characterization of volume holographic optical elements recorded in Bayfol HX photopolymer for solar photovoltaic applications

“…Two kinds of photosensitive materials proven to be suitable for the recording of holographic lenses as solar concentrators are dichromated gelatin (DCG) [5,[8][9][10][11] and photopolymers [12][13][14]. Both of these materials can be self-produced or acquired from manufacturing companies and provide high efficiency, resolution, index modulation and transparency.…”