THERMAL PERFORMANCE ANALYSIS OF A CONCENTRATING BEAM SPLITTING HYBRID PVT COLLECTOR

摘要

Typically the maximum fluid outlet temperature of a solar photovoltaic/thermal PVT collector is limited by the maximum operating temperature of the silicon PV cells. Spectral beam splitting has been demonstrated as a means of decoupling the thermal absorber from the PV cells, allowing thermal energy outputs in excess of the optimal PV cell operating temperatures. The current work describes the thermal performance analysis of a concentrating hybrid beam splitting PVT system designed to operate on linear concentrators and generate high-grade thermal output up to 150°C together with a secondary low-grade thermal output at around 60°C. Computational heat transfer simulations were conducted at various operating conditions in order to explore the heat loss and thermal efficiency of the hybrid receiver. PV cell temperatures were shown to remain below 75°C under worst case scenarios. Hot stream thermal efficiencies of around 50% were demonstrated under typical ambient operating conditions. The effects of convective heat loss were shown to significantly degrade the thermal efficiency.