关键词: 可再生能源, 盐穴氢储能技术, 绿氢, 度电成本分析

Abstract:

Combining the current developmental renewable energy and hydrogen energy trends in China, this paper summarizes the current developmental status of an underground salt-cavern hydrogen-storage technology at home and abroad. Consequently, it was evident that the abundant renewable energy and underground salt cavern resources in Jiangsu Province, including the good coincidence of resource and energy storage sites, were ideal for developing this technical route. Therefore, we systematically analyzed the feasibility of this coupled power generation renewable energy technology, including that of the salt-cavern hydrogen-energy storage and these technical route's full-cycle power generation costs. Investigations revealed that this technical route recovered renewable energy in the form of chemical energy by electrolyzing water from renewable energy to produce hydrogen, then stored this energy on a large scale through underground salt caverns, which used fuel cells to generate electricity for reusing renewable energy when needed. Next, this paper comprehensively considered and analyzed the cost of hydrogen production, including hydrogen storage and re-power generation, and then conducted a preliminary analysis of the kWh costs of re-power generation for this technical route. The results showed that the current cost of electricity reproduction was high, about 1.88 CNY/kWh, of which the cost of electricity and equipment accounted for 61.1% and 25.6% of the total cost, respectively. We also discovered that if the interference power generated by renewable energy was used to electrolyze water to produce hydrogen, the cost of related equipment in the technical route was reduced to 50% of the current, thereby reducing the electricity cost in the technical route to 0.49 CNY/kWh. Additionally, if reducing the power generation cost of the technical route further was necessary, a reliance on the progress of technological and manufacturing levels was needed to improve the power generation efficiency of the fuel cell further. To this end, we observed that if the fuel cell efficiency was increased to 60%, the cost of the technical route could be further reduced to 0.43 CNY/kWh, which was the same as the current electricity price. It also had practical application values. Hence, we propose that industrial and technological progress should improve China's energy security and competitiveness in the international energy field, helping her realize the optimization and transformation of the energy structure, including her peak carbon dioxide emission and carbon neutrality goals, as soon as possible. Moreover, with an improvement in the technical level and efficiency of equipment, such as electrolyzers and fuel cells, in the future, this technical route could also have extremely high application prospects.

Key words: renewable energy, salt cavern hydrogen storage technology, green hydrogen, kWh cost analysis