Evaluation of energy storage in integrated energy systems

In the context of the globally agreed decarbonization, Germany aims in a reduction of CO2 emissions by at least 80 % by 2050. In this work, power-to-gas (PtG) and power-to-power (PtP) storage systems are investigated based on computer-aided simulations and compared to scenarios without additional storage. The results reveal that cross-sector PtG systems reduce not only CO2 emissions but also costs by the displacement of natural gas. A maximum share of renewable energies in total demand of 53.4 % is possible. PtP storage systems are hardly feasible. Investment costs are that high, that CO2 reductions are with little exceptions associated with an increase in global costs. Here, hydrogen storage is the most cost-efficient option resulting in a renewable share in electricity demand of around 76 %.