The objective of eStorage is to develop cost-effective solutions for the widespread deployment of flexible, reliable, GWh-scale storage across EU, and to enhance grid management systems to allow the integration of large share of renewable.The key issue we plan to address is the need for power regulation during low demand periods, when only inflexible baseload generation and intermittent renewable generation are operating. In contrast to conventional generation, a storage plant able to regulate its consumption could help to avoid curtailing wind.Conventional Pumped Storage Hydro Plants (PSP) can only regulate their power in generation mode; variable speed technology for PSP can bring the additional flexibility in pumping mode as well. Developing technically and economically feasible solutions in eStorage will allow upgrading a significant part of European PSP capacity to variable speed, providing up to 10 GW of additional regulation capability with no environmental impact and little administrative burden, all at a much lower cost than developing new plants.We will also develop and demonstrate solutions for coupling the dispatch of storage plants with renewable generation using advances Energy Management Systems. This will enable storage plants to maximise their value in the balancing markets.. From simulation studies, demonstration results and storage potential analysis we will evaluate the system-level benefits of storage and identify development barriers in order to draw recommendations for efficient market and regulatory framework to maximise the impact of project outcomes.eStorage gathers major stakeholders from the entire value chain across EU (Elia – TSO, EDF – Generation Company, Imperial College – Academic Institution, Kema – Engineering Consultancy and Alstom – Equipment Manufacturer).