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

Table 1

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

Author	a	b	Region of application
Turton (1987) [20]	0.30	0.40	Tropics
Fagbenle (1990) [21]	0.28	0.39	Tropics
Otu-Danquah (1990) [22]	0.27	0.45	Ghana (everywhere)
Jackson and Akuffo (1992) [23]	0.25	0.45	Kumasi, Ghana
Augustine and Nnabuchi (2009b) [18]	0.29	0.42	Tropics
Proposed model	0.22	0.43	Kumasi, Ghana