Optimal calculation of the operation strategy of a distributed heating system combining wind, solar and electrical energy

Abstract

In this paper, a distributed combined heating system is proposed, composed of an electrically driven air source heat pump (two-stage compression type), solar collector, wind turbine heater, and thermal storage device. A multi-objective optimization mathematical model is established, aiming to minimize the operating cost and carbon dioxide emission during a certain time. The multi-objective planning problem is used to guide solutions to building heating problems in Northern China. Subsequently, for a specific example, the NSGA2 algorithm is used to solve the calculation. Based on the compromise solution of the two optimization objectives, the optimal operation strategy is determined: the amount of heat generated or stored by each device on a typical day. The optimal operating strategy is as follows. In the low heat load period (9:00-16:00), which coincides with the sunny period, the heat production of the solar collectors and the wind turbine heaters exceeds the heat load, and the storage device stores surplus heat. During peak hours (0:00-9:00, 16:00-24:00), the solar collectors are not activated because the solar irradiance is nearly zero. And at this point, the heat production by the wind turbine heaters fluctuates greatly, and the air source heat pump turns out to be the main heating equipment and the heat storage device to release heat when necessary.