The investigation on a hot dry rock compressed air energy storage system

For the strict site requirement and the consumption of fossil fuel in compressed air energy storage system, the large-scale application of compressed air energy storage is limited. In this paper, a hot dry rock compressed air energy storage system is proposed, and the cracks of hot dry rock are used as the storage place of compressed air. Meanwhile, the thermodynamic model and wellbore model are constructed to evaluate the performance of proposed system. In the range of mass flow rate and recharge pressure of present work, the numerical results illustrate that the production temperature increases with the augment of the mass flow rate, but the increase of the recharge pressure has no obvious effect on the production temperature. Besides, the consumption of valley electricity increases with the augment of mass flow rate and the reduction of the recharge pressure. In addition, the round trip efficiency of the system fluctuates between 48.59%similar to 54.88%, which is much better than that of the traditional compressed air energy storage system (42%).

Automated summary

A hot dry rock compressed air energy storage system is proposed in this paper, which utilizes the cracks of hot dry rock as the storage place for compressed air, solving the strict site requirement and fossil fuel consumption issues. The performance of the system is evaluated through thermodynamic and wellbore models, and the results indicate that the production temperature increases with the mass flow rate, while the recharge pressure has little effect on it. Moreover, the consumption of valley electricity increases with the mass flow rate and decreases with the recharge pressure. The round trip efficiency of the system fluctuates between 48.59% to 54.88%, which is much better than the traditional compressed air energy storage system.