On the estimation of global solar insolation

A curve suitable for estimation of global solar energy insolation in equatorial regions has been generated from humidity considerations using an empirical “universal” formula and experimental solar insolation data recorded for over 20 yr at specific locations in Kenya, East Africa. The curve has then been used to estimate global insolation in other locations in Kenya and the neighbouring countries with longstanding experimental data. The agreement between the experimental and theoretical insolation values is found to be satisfactory. This curve, we believe, can serve a useful purpose in estimating global solar insolation in other tropical locations with similar climatic conditions as those in Kenya which lack proper global solar insolation acquisition equipment.