Multi-dimensional comprehensive evaluation of multi-energy complementary energy system

Low-carbon and sustainable development has drawn much attention in social communities in recent years. The conventional single energy system cannot meet the urgent needs of sustainable energy against the background of energy shortage, due mainly to the low utilization efficiency and many deficiencies in technology. As a result, a multi-energy complementary energy system has emerged at present. It is necessary to fully evaluate the implementation of multi-energy complementary energy system for the economic and social benefits. In this article, a system architecture was first designed, according to the "source-network-load-storage" structure, including energy inputs (such as wind, light, gas, and electricity), load demand for electricity, heat, cold, and gas, as well as energy conversion equipment (such as gas turbines, electric refrigerators, and electric boilers). Then, the demand relationship was established among the three stakeholders: energy suppliers, local governments, and energy users. Five levels were set to be evaluated, including the clean and low-carbon, safe and reliable, energy utilization, high-efficiency economic, and social service level. An evaluation index system was then constructed for the multi-energy complementary energy system, including 5 first-level and 45 second-level indicators. The detailed indicators were defined, such as the proportion of electric heating (gas) replacement time, energy storage equipment (battery, heat storage tank, and gas storage tank) peak shaving capacity, user smart energy participation, and energy business online operation rate. Among them, the G1 was used for the subjective weighting of indicators, while the CV was used for the objective weighting, where the subjective and objective weights were combined, according to the optimal comprehensive weight using the maximizing deviation method. As such, this weighting was adopted the expert opinions, together with the indicator data. The improved multi-level matter-element extension was used to comprehensively evaluate the multi-energy complementary energy system. Finally, the evaluation was implemented using G1-CV maximum deviation comprehensive weighting-multi-level matter-element extension, particularly suitable for the three-level evaluation index system. In addition, an example was selected to verify the evaluation index system. Consequently, the comprehensive evaluation can also be expected to serve the construction and operation for different multi-energy complementary energy systems, further to obtain refined evaluation from various dimensions. This finding can also provide a theoretical guidance for the optimal planning of energy system. © 2021, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.