In this communication, an attempt has been made to develop a characteristic equation known as improved Hottel-Wheelier-Bliss (HWB) equation for Fresnel Lens integrated Semi-transparent photo-voltaic Thermal (FLiSPVT) Liquid collector as a function of design and climatic parameters. The analysis is based on energy balance equation for each components of the proposed FLiSPVT liquid collector. It has been observed that FLiSPVT liquid collector is better and economical in comparison with semi-transparent photo-voltaic thermal (SPVT) liquid collector in terms of thermal gain as well as electrical gain.