An overview of large-scale stationary electricity storage plants in Europe: Current status and new developments

Pumped hydro energy storage (PHS) currently is the only electricity grid storage technology with substantial deployment throughout the world, representing over 99% of storage capacity, but other storage technologies such as batteries are increasingly finding application. In Europe, the implementation of storage systems is expected to increase because of the integration of intermittent, nondispatchable renewable energy sources. Nevertheless, there is no overview available of the power and energy ratings of large-scale stationary storage at the supranational level. In the absence of officially collected statistics on energy capacity, publicly available information is collected from storage owners, freely accessible databases, scientific articles, reports, brochures and government websites. The status of PHS and other large-scale storage technologies in the EU-28 countries, supplemented by Norway and Switzerland, is presented. First, this paper defines a measure of energy storage capacity, to allow comparison of pumped hydro storage plants with other storage technologies. Next, a set of technical parameters of current large-scale storage plants is presented, as well as an overview of planned storage projects. The estimate of PHS power ratings in the EU-28 exceeds previous estimates, with a total of 160 plants and 45.283GW rated power in turbine mode and a full cycle storage capacity of 602GWh. When adding Norway and Switzerland, a total of 188 operational PHS plants is shown with 1313GWh. The data is used to obtain EU-wide discharge curves and national indicators of utilization and significance.