Subsurface System Design and Feasibility Analysis of Compressed Air Energy Storage in Aquifers

Abstract:

A concept model for compressed air energy storage system in aquifer (at a depth of 800 m and with a permeability of 0.5×10-12 m2) was designed and investigated through numerical simulations. The pressure variation, gas plume evolution and system cycle times during the formation of initial gas bubble and system daily cycle were analyzed. The modeling results show that there is a small change in pressure and gas saturation after each daily cycle. However, the total effective gas volume in gas bubble decreases with cycle continuing. Makeup gas should be injected into gas bubble during daily cycle or carry out another gas bubble injection after cycle is ceased. The comparisons of daily cycle and weekly cycle scenarios indicate that weekly cycle needs higher requirement for system. Aquifers as storage tank for compressed air energy storage is feasible and should be designed according to the specific geological conditions.