Modeling and assessment of a novel solar-biomass based distributed multi-generation system

In this research, a distributed multi-generation system combining photovoltaic-thermal collectors with biomass generating units is established in a numerical simulation environment. This system aims to fulfilling heating demand of single-storey cottage located in Xi'an, Northwest China. The feasibility of this system and stepped utilization of different levels of energy are validated and illustrated. In order to achieve reachable maximum efficiency, key parameters of the system, such as collector area, thermal storage capacity, and set heating temperature among other parameters, are combined in a multitude of different ways, and a set of optimal parameters are obtained. After running the model, throughout the heating season, the results show that solar energy contributes 1698 kWh accounting for nearly 60% of the total energy input, while biomass accounts for 40% with 852.95 kWh, which directly determines the stability of the system energy supply. Once-daily maximum electricity buffer generated by the biomass generator holds at 21.67 kWh, the system is able to meet most of the heating load scenarios in Xi'an, China, without auxiliary energy input, as well as achieves the carbon neutrality goal.