Energy storage technologies will play a crucial role in increasing both the efficiency as well as the availability of renewable energy. Compressed Air Energy Storage (CAES) enables the efficient and cost effective storage of large amounts of energy usually above 100 MW. However, this technology is limited by the inherent risks of underground exploration. In order to reduce this handicap, we propose a mini-CAES concept where the cavity is shallower than current CAES. This concept re-defines energy storage capacity with storage capacity power in the range 10-100 MW, thus minimizing the impact on the surface and making it less expensive than conventional CAES. The findings describe the technical parameters to be considered for mini-CAES and the relationship thereof with energy storage capacity. As a result of this study, the subsurface infrastructure and its interactions with the surface, and energy conditions have been optimized. Mini-CAES is more suitable for renewable energy than deeper CAES. (C) 2017 Elsevier Ltd. All rights reserved.