Hybrid azimuth-tracking intermediate photovoltaic concentrator system

The design and fabrication of a low-concentration photovoltaic array is described. The concentrator consists of horizontal reflector troughs floated on a shallow 10 meter diameter pond and tracked in azimuth. One-sun panels are used in the receiver to produce dc power. Thermal energy is collected from the panels by circulated water and is stored in the pond. Performance data for two days are shown and used to estimate annual array performance. Peak efficiency is 5.5% and annual energy produced in Tucson is estimated to be 71 kWh/m/sup 2/ (roughly 3% annual efficiency).