Abstract In this communication, an attempt has been made to develop modified Hottel-Whillier-Bliss (HWB) equation for N-number of fully covered photovoltaic thermal- compound parabolic concentrator (N-PVT-CPC) collector. The Analysis is based on basic energy balance equations for each component of the system as a function of design and climatic parameters. Developed modified Hottel-Whillier-Bliss (HWB) equation is applicable for various configurations namely conventional flat plate-compound parabolic concentrator (FPC-CPC), fully covered photovoltaic thermal-flat plate collectors (PVT-FPC) and conventional flat plate collectors (FPC) as a special case. The characteristic curve for thermal and electrical efficiency has also been developed for all cases considered in the present paper. Further, an experimental validation for N = 1 has also been carried out under indoor simulation condition.