Booster reflectors for PV modules in Sweden

Abstract

The performance of photovoltaic modules with planar booster reflectors with variable length and tilts for Swedish conditions is analyzed. It is shown that a stationary flat booster reflector can increase the annual output of the module in the order of 20-25%, provided that the influence of short lateral length of the reflector and temperature rise can be limited. The principal difference between using modules with crystalline silicon cells or thin film modules is discussed and numerical examples together with experimental results are given. The electrical coupling of rows in a PV module and/or the electrical coupling of modules in a PV installation are important when booster reflectors are used. If horizontal rows of cells in a module are parallel coupled, the module better utilizes radiation reflected from a booster reflector in front than if the rows are coupled in series. Low serial resistance, low module temperature and small edge effects, i.e. not too short lateral length of the booster reflector, are important to achieve good performance of modules with booster reflectors.