PUSH-CCC proposes to solve the key existing limits of Compressed Air Energy Storage (CAES) scalability, replicability, efficiency, and energy density while boosting its cost-effective commercial development in Europe by bringing a breakthrough CAES concept to TRL4, which is based on a novel optimized integration of advanced technology and scientific advances beyond the state of the art, pushing the efficiency and profitability of the volatile-fluid-based isobaric adiabatic Combined Cycle CAES (CCC) patented by RIEGOSUR, a scientifically proven high-potential concept due to the enhancement of turbomachinery efficiency and cavern volume minimization.