Point-focus spectral splitting solar concentrator for multiple cells concentrating photovoltaic system

TL;DR

This paper introduces a low-cost, spectrally splitting solar concentrator that concentrates sunlight and separates it into spectral components, achieving high concentration ratios and high optical transmissivity, suitable for efficient photovoltaic systems.

Contribution

The paper presents a novel, low-cost, dual-axis concentrating spectral splitter device with experimental validation, improving upon previous designs for photovoltaic applications.

Findings

Achieved spectral separation within a 3x1 cm² area.

Maximum concentration ratio of 210x for a single wavelength.

Optical transmissivity above 90% in 400-800 nm range.

Abstract

In this paper we present and experimentally validate a low-cost design of a spectral splitting concentrator for the efficient conversion of solar energy. The optical device consists of a dispersive prismatic lens made of polycarbonate designed to simultaneously concentrate the solar light and split it into its spectral components. With respect to our previous implementation, this device concentrates the light along two axes and generates a light pattern compatible with the dimensions of a set of concentrating photovoltaic cells while providing a higher concentration ratio. The mathematical framework and the constructive approach used for the design are presented and the device performance is simulated using a ray-tracing software. We obtain spectral separation in the visible range within a 3x1 cm2 area and a maximum concentration of 210x for a single wavelength. The device is fabricated by injection molding and its performance is experimentally investigated. We measure an optical transmissivity above 90% in the range 400-800 nm and we observe a spectral distribution in good accordance with simulations. Our results demonstrate the feasibility of the device for cost effective high efficiency concentrated photovoltaic systems.