Spectral-shifting and holographic planar concentrators for use with photovoltaic solar cells

Two types of solar concentrators for use with standard silicon photovoltaic cells are compared. The first is a spectral shifting luminescent concentrator that absorbs light in one spectral band and re-emits light at longer wavelengths where the absorption of standard silicon photovoltaic cells is more efficient. The second type is a holographic planar concentrator that selects the most useful bands of the solar spectrum and concentrates them onto the surface of the photovoltaic cell. Both types of concentrators take advantage of total internal reflected light, do not require tracking, and can operate with both direct and diffuse sunlight. The holographic planar concentrator provides a simpler and more cost effective solution with existing materials and construction methods.