A RATING PROCEDURE FOR SOLAR DOMESTIC HOT WATER-SYSTEMS BASED ON ASHRAE-95 TEST-RESULTS

A rating method for solar domestic hot water (SDHW) systems is presented that provides site-specific annual performance estimates based on ASHRAE-95 test results. An overall loss and overall gain coefficient are estimated by lumping the entire thermal behavior of the actual system exhibited during the ASHRAE-95 test into the collector parameters of a simplified system model. The performance of the simplified model can then be predicted using either the F-chart or TRNSYS and presented as an estimate of the annual performance of the actual system. Experimental performance measurements taken from relevant literature as well as extensive simulations, indicate that this method is capable of predicting the annual performance of a wide range of SDHW system types to within 5%, independent of location.