Holographie planar concentrator increases solar-panel efficiency

The holographic planar concentrator (HPC) has emerged as a significant approach, to reduce the cost of solar power and improve the efficiency of solar cells. A HPC is built from several layers of film, composed of gelatin on polyethylene terephthalate. Holographic optical elements are imprinted on each film, using diode-pumped solid-state lasers. The holographic film diffracts wavelengths that can be used by solar cells, while allowing unusable wavelengths to pass through, without being absorbed. The usable energy is guided through total internal reflection at the glass/air interface of solar cells, resulting in significant concentration of energy per unit area of photovoltaic material. The efficiency of an HPC-equipped solar cell module remains high for lower-light conditions, generating significantly higher yield in real-world lighting conditions.