In this paper, the design and fabrication of photovoltaic thermal integrated greenhouse system (PVTIGS) for biogas heating has been done for climatic condition of IIT Delhi, India. PVTIGS can also be used for a number of applications like generating electricity, space heating, enhancing production of biogas, crop cultivation and crop drying, etc. Thermal modelling of proposed system (PVTIGS) without load has been developed based on energy balance equations. Further, with the help of thermal modelling the solar cell temperature, room temperature and solar cell efficiency have been calculated for a typical clear day of May. Experimental validation have been done on the basis of correlation coefficient (r) and root mean square percentage deviation (e) and found to be in fair agreement between theoretical and experimental values. Effect of packing factor, mass flow rate of air below module, absorptivity (degradation effect) and transmittivity (dusting effect) on thermal load levelling have been discussed. Electrical energy has been calculated and validated with experimental values. Further, thermal energy and overall thermal energy have been evaluated and found to be 11.18 kW h and 12.76 kW h respectively for a clear day without load. © 2016 Elsevier Ltd