Solar powered combined ejector vapour compression cycle for air conditioning and refrigeration

Refrigeration and air conditioning play important roles in providing human comfort, food processing and storage and many other industrial processes. These applications are generally powered by electric energy. On the other hand, solar energy is widely available and has no fuel cost, which makes the running of solar powered refrigeration a viable and economic proposition. Unfortunately, research shows that solar powered conventional refrigeration systems have a relatively low coefficient of performance (COP). This paper describes a new way for harnessing solar energy, using a combined ejector-vapour compression cycle. This combined cycle brings together the advantages and eliminates the disadvantages of the two common conventional cycles. H2O is used as the refrigerant in the ejector sub-cycle and HFC-134a in the vapour compression sub-cycle. The study shows that the combined cycle is: (i) a potentially high performance system with a potential increase in system COP by more than 50% over the conventional cycles; (ii) a ''green'' system that conforms to all foreseeable ozone preserving regulations and reduces ''green house'' effects; and (iii) a cost effective system with low maintenance. (C) 1997 Elsevier Science Ltd. All rights reserved.