Batteries are one of many storage technologies in development. Scottish Company Gravitricity are using spare electricity to lift very heavy weights to the top of very deep shafts and then, when we need the wattage, they can be dropped to spin turbines.

HighView Power is using excess power to compress and refrigerate air, then store it in tanks for as long as required. When peak demand comes, the air is allowed to expand and, once again, drive generators. Hydrogen has a potential role in storage too: use electricity for the energy intensive process of breaking hydrogen out of water. Getting the H from the H2O gives you a tank of that zero-carbon fuel.

Dan McGrail, from the trade body Renewable UK, says: “We’re going through one of the biggest changes in our energy system of all time at the moment. So having energy, energy storage in the system is going to be a really vital component of how the system works in the future and stays in balance to provide electricity for homes and businesses.”

Merseyside’s mega-battery is switched on – and here’s how it will save billions of pounds off bills and huge amounts of CO2 | Climate News | Sky News