Analysis of yearly solar radiation by using correlations based on ambient temperature: India

Solar energy technologies offer a clean, renewable and domestic energy source, and are essential components of a sustainable energy in the future. This paper presents the comparison of yearly mean daily solar radiation using temperatures of different cities in Andhra Pradesh, India from April 2010 to March 2012. The main objective of this paper is to comparing the potential of monthly solar radiation using air temperatures at three cities (Hyderabad-17.37° N, 78.43° E, Vishakhapatnam-17.7° N, 83.4° E and Anantapur-14.6° N, 77.6° E) of Andhra Pradesh, India. Solar radiation is the principal, fundamental and abundantly available energy for many physical, chemical and biological processes. However, it is measured at a very limited number of meteorological stations in the world. Proper and adequate information on solar radiation and its components at a given location is very essential in the design of solar energy systems. Since the temperature is probably the most registered meteorological variable, correlation models based on air temperature data are especially interesting to compare monthly average values of solar irradiation in countries with lack of direct measurements. The Hargreaves equation was used to estimate the solar radiation. Measured long-term monthly air temperatures including Tmax and Tmin, were gathered from meteorological stations and analyzed. Three combinations of air temperatures, namely Tmax, Tmin, and Tave were served as inputs. The approach in this present paper seems to be adequate to the data obtained from meteorological stations supported by organizations web site in India. The Vishakapatnam weather conditions are entirely different because of a diverse orography on the eastern Indian coast than other cities.