LED solar spectrum simulator

Abstract

This paper is intended to report a solar spectrum simulator based on high power LED (Light-Emitting Diode) as the source of radiation for the tests and trials of systems that otherwise would depend on the natural solar radiation. Among the devices that would benefit from this simulator for testing are solar thermal collectors and photovoltaic cells. Traditionally, solar simulators employ metal halide, xenon or tungsten halogen lamps, which consume much more power than Leds and have a shorter life, around 1000 hours. Furthermore, these simulators only approximate the spectral characteristics of natural sunlight because of the mismatch between the spectrum of radiation generated and the natural solar spectrum. The light-emitting diodes are recognized for their low power consumption and its small dimensions. Recent advances in led technology have provided high power and high efficiency devices. Leds with power levels of radiation in the order of 100 mW and reduced dimensions are now available. Moreover the power radiated can vary from 0 to 100% by controlling the current flowing through the leds. This makes it possible to reproduce the solar spectrum with high fidelity.