Herefordshire Council has given planning permission for the building of a 20MW energy storage system (ES) which will give real-time grid stabilisation to the local distribution network. Energy Reservoirs now has three years to start building the system, which will be made up of batteries housed in ten containers on a greenfield site to the west of Clay Hill Pitch, Dormington. The original planning documents state that the system will be directly connected to the adjacent substation to provide energy storage capacity to the National Grid. It will mean that excess electricity generated from a number of conventional and renewable sources will be allowed to be stored in the batteries during times of low demand. The stored capacity will then be fed back into the grid during peak demand times, which can coincide with times of low generation. A spokesperson for Energy Reservoirs said that in terms of other potential streams of revenue, the process of prequalifying for the capacity market was “an expensive job” for a battery due to the high bid bond require, while arbitrage “doesn’t really work yet sadly”. The project is therefore expected to rely on providing frequency balancing services as the main revenue stream. However, the spokesperson added that the company intended to take part in National Grid’s next tender after failing to win in the recent EFR competition. Energy Reservoirs has yet to appoint a supplier and is currently attracting quotes from a number of potential partners, the majority of which are offering lithium-ion batteries.