A comprehensive feasibility evaluation of hydrogen-carbon-salt cavern-renewable energy (HCSR) system

Abstract

Renewable energy utilization, hydrogen energy development, and carbon emissions reduction are crucial methods to build a green and clean society. However, the problems with the large scale of energy utilization and storage efficiency restrict the growth of the above methods. To solve these problems, a hydrogen-carbon-salt cavern-renewable energy (HCSR) system that produces and stores the CH₄, CH₃OH, CO, and petrol was proposed based on the principle of power to gas (PtG). To analyze the feasibility of the HCSR system, a comprehensive evaluation system that includes three evaluation models (economy model, geological stability, and environment model) was built. The application prospect, energy conversion, system sensitivity, and system limitations were discussed. The study showed that the HCSR system (power to petrol) can save $1.68\times {10}^{10}\text{dollars}$ and $1.79\times {10}^{10}$ dollars compared to the surface storage tanks and rock cavern storage in 2024, and the economy of the HCSR system was greater than other traditional systems. The maximum displacement, effective strain, and dilatancy of the salt cavern energy storage (SCES) in salt caverns with interlayers were 4.5 m, 0.18 , and 0.4 , respectively, and these parameters satisfy the stability criteria. The maximum environmental parameters of the HCSR system were the zero-carbon circulation and utilization of renewable energy, which account for 43.06 % and 23.12 %. Geological stability was the most sensitive parameter (54.13 %) in the HCSR system. The system will contribute to the development of zero-carbon circulation and energy transition.