Exergy Analysis of Solar Radiation Based on Long Term for Van City

The present study has analyzed the solar radiation exergy for the period of 1993 to 2007 in Van (38.28 o N, 43.20 o E). In this regard, various models have been applied for determination of solar radiation exergy. The exergy efficiency of solar radiation taken from meteorological data is evaluated based on these models for Van. According to results, the highest long term monthly average solar radiation exergy values is observed in June with 26.85 MJ/m 2 for Petela Model and same result also is observed for Spanner model but Jeter’s approach is different from these models approximately %1.7. The ratio of solar radiation exergy to the long term monthly average solar radiation energy values varies from 0.934 to 0.939 both Spanner and Petela approach, and from 0.950 to 0.954 for Jeter’s approach. The highest annual value  exergy of the solar radiation is observed for the year of 2000 with 19.68 MJ/m 2 and the lowest annual value exergy of the solar radiation is found for the year of 1993 with 16.50 MJ/m 2 .