Generalized models for estimation of diffuse solar radiation based on clearness index and sunshine duration in India: Applicability under different climatic zones

摘要

Abstract Generalized models for assessment of monthly average diffuse solar radiation over India were established using long-term solar radiation data available for 15 years (1986–2000) obtained from Indian Meteorological Department (IMD), Pune. Regression analysis was employed to correlate the diffuse fraction ( K ? d ) with clearness index ( <