A novel achromatic Fresnel lens for high concentrating photovoltaic systems

The paper presents a novel Fresnel lens for concentrator photovoltaic (CPV) technologies with reduced chromatic aberration that allows increasing the attainable concentration. Although achromatic doublets for CPV have previously been proposed, they were based on coupling two plastic materials but no practical fabrication procedure was described. Here we present for the first time a cost-effective manufacturing process consisting in laminating a high-dispersion plastic, a low-dispersion elastomer and a rigid glass substrate. Ray-tracing simulations showed a concentration factor three times higher than that attained by a classic Silicone On Glass (SOG) Fresnel lens while maintaining the same acceptance angle. Due to the cost-effective manufacturing process the significant performance increase due to the higher concentration could be attained at a cost comparable with the current manufacturing cost of a conventional SOG Fresnel lens. Even taking into account the small efficiency loss resulting from the more complex geometry (about 4%) we believe that this novel concept may introduce a disruptive change in optics for CPV