Commercialisation of Energy Storage

This report was created to ensure a deeper understanding of the role and commercial viability of energy storage in enabling increasing levels of intermittent renewable power generation. It was specifically written to inform thought leaders and decision-makers about the potential contribution of storage in order to integrate renewable energy sources (RES) and about the actions required to ensure that storage is allowed to compete with the other flexibility options on a level playing field.
The share of RES in the European electric power generation mix is expected to grow considerably, constituting a significant contribution to the European Commission’s challenging targets to reduce greenhouse gas emissions. The share of RES production in electricity demand should reach about 36% by 2020, 45-60% by 2030 and over 80% in 2050.
In some scenarios, up to 65% of EU power generation will be covered by solar photovoltaics (PV) as well as on- and offshore wind (variable renewable energy (VRE) sources), whose production is subject to both seasonal as well as hourly weather variability. This is a situation the power system has not coped with before. System flexibility needs, which have historically been driven by variable demand patterns, will increasingly be driven by supply variability as VRE penetration increases to very high levels (50% and more).
Significant amounts of excess renewable energy (on the order of TWh) will start to emerge in countries across the EU, with surpluses characterized by periods of high power output (GW) far in excess of demand. These periods will alternate with times when solar PV and wind are only generating at a fraction of their capacity, and non-renewable generation capacity will be required.
In addition, the large intermittent power flows will put strain on the transmission and distribution network and make it more challenging to ensure that the electricity supply matches demand at all times.
New systems and tools are required to ensure that this renewable energy is integrated into the power system effectively. There are four main options for providing the required flexibility to the power system: dispatchable generation, transmission and distribution expansion, demand side management, and energy storage. All of these options have limitations and costs, and none of them can solve the RES integration challenge alone. This report focuses on the question to what extent current and new storage technologies can contribute to integrate renewables in the long run and play additional roles in the short term.