Optimal configuration of multi-energy stations in coal mines under regional source-load balance

To meet the "dual carbon" goals, the transformation of mining energy systems is required. The issues of scattered source-load distribution and insufficient multi-energy synergy in underground coal mines located in central and western China are adddressed in this paper. An optimization method for multi-energy station configuration based on regional source-load distribution is proposed. Firstly, three types of energy stations are defined in this study: energy-consuming stations, energy-exporting stations, and small-scale thermal stations. This architectural design takes into account the distinct load characteristics and resource endowments of core production areas, auxiliary industrial areas, and logistic areas. Secondly, refined production-consumption models are established. These models incorporate mining-excavation-transport equipment, drainage systems, ventilation systems, renewable energy systems, and energy conversion systems. Mine safety requirements and auxiliary equipment operation rules are also integrated into the models. The optimization objective is set to minimize the total annual comprehensive cost. Through this method, the capacity of equipment and the strategies for cross-regional electricity/heat exchange are optimized. A western coal mine with an annual output of 5 million tons is selected as a case study to verify the proposed model. Four configuration scenarios are considered in the analysis: scenarios without power generation equipment, with power generation equipment, with full equipment and adjusted maintenance periods, and with full equipment while considering renewable energy uncertainty. Additionally, a special scenario with 30% load fluctuations is included. Simulation results indicate that local energy consumption efficiency is significantly improved by the regional synergistic architecture. The cost of purchased electricity is reduced by 64.29% through the system. A 61.44% reduction in the total cost is achieved by adjusting maintenance periods to align with peak-valley price periods, in comparison with the first scenario. The system cost is increased by 7 500 yuan due to renewable energy fluctuations. Nevertheless, the economic viability and operational reliability of the system are maintained under load uncertainty conditions. The effectiveness of the proposed configuration method is verified by these results.