Author: Lei Gu (Tianjin University) - As an important supplement to the centralized energy system, the distributed energy system has the advantages of flexible layout and high energy efficiency. Solar dish collector can also be flexibly configured and output high-temperature thermal energy, making it an ideal energy supply unit for distributed energy system. However, the conventional solar dish Stirling system has single function and low reliability. In particular, the Stirling engine has high cost, complex regulation, and is difficult to couple with the thermal energy storage, resulting in the lack of competitiveness compared with other solar energy application schemes. This research used photovoltaic module to replace Stirling engine and established a typical hybrid system of solar dish collector and photovoltaic for the application scenario of distributed energy systems, and conducted comprehensive assessment of the performance and economy of the hybrid system in three cities with different solar irradiance conditions, Tianjin, Yinchuan and Lhasa. The results showed that the daily thermal load satisfaction rate of the system during the heating season was higher than 50%, especially in Yinchuan and Lhasa with good radiation conditions, which can reach 83.44% and 96.69% respectively. The daily electrical load satisfaction rates of the system using 15kW photovoltaic module in Tianjin, Yinchuan, and Lhasa can reach 29.80%, 49.67%, and 94.70%, respectively. By using 20kW photovoltaic module, the corresponding values can be further increased to 51.66%, 84.77% and 98.68%. In economy, the lowest levelized electricity cost for matching 20kW photovoltaic module in three cities were 2.12 CNY/kW·h, 1.41 CNY/kW·h, and 0.81 CNY/kW·h, respectively.
