Japanese, British and European companies are expected to compete for the 200 megawatts project, which will be used to plug the gap when Britain's doesn't have enough power.
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One bidder, American firm AES, said that the energy stored will be equivalent to that generated by more than a million iPhone-sized lithium-ion batteries, according to the Times.
The scheme is increasingly important given the number of coal-fired power plants that are going offline, as well as the intermittency of renewable energy sources such as wind and solar.
A spokesman for National Grid said: "It will support the UK’s energy mix in a rapidly changing market. Contracts will be announced at the end of August."