Empirical Models for Estimating Global Solar Radiation over the Ashanti Region of Ghana

Table 2

Summary of the regression constants used by different authors in the tropics as well as that proposed by this paper, based on air temperature measurements.

Author	a	b	Model form
Hargreaves and Samani (1982) [14]	0.153	−0.033	𝑅=𝑎(Δ𝑇)^0.5+𝑏
Chandel et al. (2005) [13]	0.264	−0.155	𝑅=𝑎ln(Δ𝑇)+𝑏
Proposed	0.311	−0.293	𝑅=𝑎ln(Δ𝑇)+𝑏