Test method for system characterization and yearly performance prediction of solar water heating systems

Abstract

As per ISO 9459: Part 2; Solar water heating systems are mainly categorised into two types
depending upon the collection of solar radiation. These are flat plate collector system and
evacuated tube collector system. The tests are performed for characterization of these two types of
systems. The tests are based on mixing of cold water with hot water for obtaining necessary
condition, runoff to determine delivery temperatures profile and determination of heat loss from the
storage cylinder. The tests were performed for a period of fifteen days and the results are
extrapolated to determine yearly performance of both above mentioned systems. After that, the tests
are repeated with auxiliary heating device. The results show that flat plate collector is having
better performance than evacuated tube collector for varying test conditions. Inferences are drawn
from the tests conducted over both systems about the performance. The effect of various parameters
like temperature difference, solar irradiation, supply water temperature and use of integrated
auxiliary heating devices are taken into consideration during the present work.