High energy yield bifacial spectrum-splitting photovoltaic system.

Abstract

In this paper a photovoltaic system is proposed that achieves high energy yield by integrating bifacial silicon cells into a spectrum-splitting module. Spectrum splitting is accomplished using volume holographic optical elements to spectrally divide sunlight onto an array of photovoltaic cells with different bandgap energies. Light that is reflected from the ground surface onto the rear side of the module is converted by the bifacial silicon cells. The energy yield of the system is optimized by tuning the volume holographic element parameters, such as film thickness, index modulation, and construction point source positions. An example is presented for utility-scale illumination parameters in Tucson, Arizona, that attains an energy yield of $1010\frac{{{ kw}\cdot { hr}}}{{{ yr}\cdot{{ m}^2}}}$1010kw⋅hryr⋅m2, which is 32.8% of the incident solar insolation.