Zhixun Wang

The goal of “carbon peaking and carbon neutrality” accelerates the development of renewable energy, and also places higher demands on industries to improve energy efficiency. On the other hand, the high proportion of renewable energy raises the operating costs of the power system, and expands the cross-subsidy to guarantee stable tariffs for residents and agriculture. To reasonably evacuate the increasing costs, a differential electricity tariff for the high-energy-consuming industry is designed in this paper. The total tariff cross-subsidy of residential and agricultural users is first calculated based on the average feed-in tariff and transmission and distribution tariffs by voltage levels. Then, a comprehensive energy consumption index (CECI) is designed to evaluate the energy consumption efficiency of each industry. Finally, the tariff increases for different high-energy-consuming industries are calculated according to the CECI of each industry, forming a differentiated apportionment of emission reduction costs for the power system.

Energy storage systems used for the flexible grid connection of wind farms in terms of minute timescale usually consist of batteries. Due to the capacity constraints of batteries, when wind energy fluctuations exceed limits continuously, this type of energy storage system topology cannot present good performance. To solve this problem, this paper introduces a hybrid energy storage system (HESS) topology consisting of batteries and a hydrogen conversion system (HCS). To achieve a flexible wind farm grid connection with a minimum energy loss, a HESS control strategy is proposed to make full use of the advantages of the HCS capacity and battery energy conversion efficiency. The optimization goal is to minimize power fluctuations, battery life consumption, and energy loss. The energy conversion characteristics of the flexible wind farm grid–connection system are also analyzed. The simulation results show that compared with other strategies using only batteries, the operating strategy using the HESS with the same cost can combine the advantages of the battery efficiency and HCS power continuity to achieve a balance between the controlling energy loss and smoothing power fluctuations.