Development of a cassette-panel transpired solar collector

Transpired solar collectors (TSCs) are an elegantly simple, façade-integrated solar air-heating technology that is widely used to pre-heat the ventilation air supply of buildings. TSCs have historically been manufactured from long profiled pre-finished steel cladding sheets and used on industrial buildings, with which they are aesthetically compatible. Buildings such as offices and multi-storey residential buildings, however, often use flat building façade elements. In order to provide architects with the choice between a profiled or flat TSC absorber, which may be more suitable aesthetically in some circumstances, a novel, flat, cassette-panel TSC (CP-TSC) solar air-heating system has been developed and trialled in situ. Two prototype CP-TSC systems were installed onto an unoccupied 1960s multi-storey residential building at Oxford Brookes University and operated for 95 days during the winter of 2010/2011. The results show that under typical operating conditions, the CP-TSCs heated the ventilation air stream by 10–15°C on clear-skied, winter days, and that this air temperature rise can be predicted by a relatively simple energy balance model.