Design and field testing of a sunflower hybrid concentrator photovoltaic-thermal receiver

Hybrid concentrator photovoltaic-thermal (CPV/T) systems generate both electricity and process heat by splitting concentrated sunlight onto CPV cells and a thermal receiver utilizing a heat-transfer fluid. Such energy co-generation increases total conversion efficiency and reduces system costs to compete with more widely used electricity and heat-generation methods in target markets. Here, we design and prototype a sunflower-like CPV/T system that collects a portion of the incoming sunlight using triple-junction CPV cells operating with an average temperature of <85°C. In the same receiver, thermal output >245°C may be generated from both waste heat from the CPV cells and a spatially separated fraction of the incoming concentrated light illuminating a heat-exchanger coil. In total, >65% of incident sunlight is converted to electricity or process heat. On-sun field tests validate this model and guide future development, and a techno-economic model demonstrates a US average levelized cost of heat of 2.5 ¢/kW t h.