OPTIMISATION OF REFLECTOR AND MODULE GEOMETRIES FOR STATIONARY, LOW-CONCENTRATING, FAÇADE-INTEGRATED PHOTOVOLTAIC SYSTEMS

摘要

The high cost of photovoltaic modules motivates the use of parabolic aluminium reflectors that increase the irradiance on the modules and thus the electricity production. Static, two-dimensional systems with low concentration ratio are appropriate for building-integration. In this work, the system geometry (module tilt and tilt of the optical axis) of systems with parabolic concentrators has been optimised for maximum annual electricity production in southern Sweden. The optical efficiency of systems with different geometries was calculated from short-circuit current measurements on CIGS modules in parabolic reflectors. The measurements were performed at incidence angles of 0–70° and a large indoor solar simulator was used as light source. The measurements were performed both for modules in concentrators and for a flat vertical module. The geometric variations of the concentrating systems were enabled by using an adjustable module plane together with a parabolic reflector of anodised aluminium. The calculated optical efficiencies were used in MINSUN to simulate annual electricity production for systems where the optical axis of the reflector has different tilt angles. A module tilt of -15° and a tilt of the optical axis of the parabolic reflector of about 45° were found to give the highest electricity yield per cell area. The highest simulated annual electricity production was 148 kWh per m² cell area, which is 70 % higher than for a flat vertical module.