ELECTRICITY REPLACEMENT BENEFITS OF VARIOUS RECEIVER COMBINATIONS IN A MULTI TOWER SOLAR ARRAY DISTRIBUTED CHP PLANT

摘要

The Multi Tower Solar Array (MTSA) may use single thermal or photovoltaic receivers, or alternatively employ two separate receivers using a beam splitting filter to allocate the solar spectrum optimally. A fully integrated MTSA system will provide both electricity and heat to cover the demand of hot water and/or air conditioning. This paper addresses the issue of what various receivers that might be used in an MTSA configuration can deliver to an end-user, both in terms of the solar fraction utilized and in terms of conventional electricity replacement. The output electricity/heat fraction may be chosen quite flexibly by selecting a suitable receiver configuration, and can be taylored for the particular pattern of energy quality in demand. In general, the more effective strategy seems to involve replacing electric or gas heating with low temperature waste heat, rather than to replace fossil fuelled vapour compression air conditioning with solar powered absorption air conditioning that requires solar heat above 100 ºC. Provided that the thermal energy produced by the system may be fully utilized, a resulting effective solarto- electric conversion efficiency of around 50% seems feasible. This is comparable to the most efficient future 100% solar-powered central combined cycle plants.