Flat Plate Collectors with Booster Mirrors

摘要

The annual performance of large high performance flat plate collector fields can be further improved by almost 70 percent. This can be achieved by introducing several improvements such as antireflective coatings and V-corrugated or honeycomb anticonvection devices and improved absorber properties (absorptance and emissivity). Booster mirrors in between the rows in a collector field will further increase the annual performance by at least 30 percent. This is achieved with no extra ground area requirement. Simulation results using a detailed model for the reflector show that the collector can be tilted at nearly the same optimum angle (45 degrees - 50 degrees) as without a reflector (40 degrees - 45 degrees). Standard corrugated roofing aluminium materials have shown surprisingly good long-term performance (four operating seasons) in spite of a visually large degradation of the reflectance.