This communication offers an investigation of photovoltaic thermal integrated greenhouse system (PVTIGS) for heating of slurry in potable biogas plant developed at IIT Delhi, India. The energy through biomass is one of the renewable and clean energy which is generated with the help of organic raw materials (such as animal dung, vegetable waste, and tree leaves) through anaerobic process. PVTIGS may utilized for different applications like making electricity, enhancing the slurry temperature (resulting in improved production of biogas), crop cultivation and cooking etc. Thermal modelling of the newly developed system (PVTIGS) with load condition has been derived. Different parameters of PVTIGS have been calculated namely, solar cell temperature, slurry temperature, greenhouse room temperature and biogas plant wall temperature with the help of thermal modelling. Further, theoretical values has been compared with experimental values. Correlation coefficient (r) and root mean square percentage deviation (e) found to be 0.93, 5.25; 0.97, 4.2; 0.98, 3.35 and 0.85, 8.07 for greenhouse room, flow air, biogas chamber and slurry temperature respectively. During sunshine hours (7 AM to 6 PM) and off sunshine hours (6 PM to 7 AM), the average temperature difference between slurry and ambient air temperature are 3.93 °C and 6.74 °C. © 2017 Elsevier Ltd