Estimation of annual collectible energy by flat plate solar thermal collectors: case study of Colombo

Abstract

The Utilizability concept has been adopted as a design method for flat plate solar thermal collector sizing. Hourly & Daily utilizability curves on a monthly time scale have been generated for the city of Colombo using hourly irradiance data on horizontal surfaces. Based on some selected curves, their specific characteristics have been shown and the method of estimating long-term collectible energy by any flat plate solar thermal collector (horizontal) installed in Colombo is highlighted. These curves will enable the carrying out of an accurate sizing of an industrial solar thermal system with least effort.