On the charge The UK battery firm aiming to unlock the way to net zero

Think of battery manufacturing and it may evoke images of Elon Musk and Tesla's sprawling "gigafactories" around the globe, or China's vast, hi-tech clean rooms churning out cells to go in anything from electric toothbrushes to mobile phones and cars. But at Invinity Energy Systems' small factory in Bathgate, near Edinburgh, workers slotting parts together are hoping that Britain can also play a part in the battery revolution.

- Jasper Jolly

These batteries, which rely on vanadium ions, are put in 6-metre, 25-tonne shipping containers. They will not go into cars, but the manufacturer hopes the technology can win a place in a global rush for storage to usher in the shift to net zero carbon grids.

Renewable electricity is the future of the global energy system: cheaper and cleaner than fossil fuels. However, its main drawback is that renewables are tied to the weather, and the sun may not be shining or the wind blowing when energy is most needed. "Time shifting" that energy generation with battery storage, so it can be used later, will be crucial. "What suddenly started to happen is that people have woken up to realise energy storage is needed to be able to deploy more renewables," said Jonathan Marren, Invinity's chief executive, at the factory, where the batteries are stacked in a row, ready to be shipped.

Experts have long been grappling with the options for storing renewable power, but the issue of the reliability of grids rose up the agenda in April when Spain and Portugal suffered a blackout. Some people rushed to blame renewable energy, although a Spanish government report said that was not the case. Nevertheless, battery storage could help grids around the world to avoid such chaos.