A Study of Suitable Meteorological Condition for Solar Collector Performance Testing for Thailand

Abstract

This research purpose is to study suitable meteorological condition for outdoor testing ofthermal efficiency of flat plate solar collector for Thailand. The condition of thermal efficiency testingof flat plate solar collector is conducted based on American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 93-1986 and Australian Standard. Solar radiation, windvelocity, and average temperature in Thailand are also taken into account in the test. Based on theabove test, the School of Renewable Energy Technology (SERT) Standard 2003, which shows solarcollector efficiency in the form of linear equation η = FR[(τα)e - UL(Ti - Ta)/It], is developed. Theequation shows the products of the heat transfer coefficient and over all heat loss coefficients (FRUL),and the heat transfer coefficient and an effective transmittance-absorbtance product (FR(τα)e). Forexample, thermal efficiency of SERT Standard 2003 is η = 0.499 - 16.996(Ti - Ta)/It, FRUL = 16.996 W/m2 0C and FR(τα)e = 0.499, of which the result is 1.2% and 5.1% different from ASHRAE and AustralianStandard respectively. The result shows that SERT Standard 2003 corresponds to International Standardsunder meteorological condition such ambient temperature and wind velocity of Thailand. ThenSERT Standard 2003 is suitable for flat plate solar collector outdoor testing in Thailand.

Keywords : Collector / Thermal Efficiency / ASHRAE Standard / Australian Standard /SERT Standard