In the deserts of the United Arab Emirates, a sprawling clean energy project covering an area roughly the size of 12,600 football fields will host a breakthrough allowing solar energy to power the equivalent of half a million homes through the night. The Gulf state has combined 5.2GW of solar power capacity with 19GWh of battery storage to create the largest battery scheme in the world. This was reported by Qazaqyia.kz citing The Guardian.

About 7,500 miles away, at the US National Renewable Energy Laboratory in Colorado, researchers and engineers are making some of the smallest batteries ever seen. Designed to power electronic tags tracking young salmon and eel species about 7.5cm long, these batteries are a fraction of the size of grid-scale lithium-ion batteries.

As traditional lithium-ion batteries push boundaries in size and scale, alternative battery types could provide the same vital role in harnessing low-carbon energy without the scramble for critical minerals like lithium, cobalt, and nickel. Unlike lithium-ion batteries, many of these alternative technologies can be used indefinitely and recycled after their 20-year service life.

Developers are turning to a wide range of materials to store renewable electricity. Here are some innovations:

Liquid air battery

Late last year, on the site of a former coal plant in Trafford, the former mayor of Greater Manchester marked the start of construction on a long-awaited energy storage project. Andy Burnham said the Trafford green cluster development could make "this decade the most exciting since the Victorian period for Greater Manchester." The Carrington project, developed by British startup Highview Power, aims to capture renewable energy when abundant and store it as liquid air. A "cryobattery" can store energy for hours, days, or even weeks. The project has faced delays but once operational at the end of the year, it will deliver 300MWh of storage and 50MW output for six hours.

Molten salt battery

While in Manchester energy is stored at sub-zero temperatures, in the Nevada desert the opposite approach is taken. Here, 10,000 panes generate electricity for the Crescent Dunes scheme, which for the past 10 years has harnessed the sun's power to heat a reservoir of potassium and sodium nitrate to 560°C. This temperature can be maintained for 10 hours after sunset, before the stored thermal energy is converted into electricity via a traditional spinning turbine. These molten salt batteries serve as primary power sources for most modern guided missiles and nuclear weapons.

In the 2020s, Denmark proved molten salt storage technology could decarbonize heavy industry. The leading wind power nation unveiled a 1GWh large-scale molten salt battery project this year, which can store clean electricity for up to two weeks by heating salts to approximately 600°C.

Sand battery

In Finland, Polar Night Energy created a "sand battery" in Pornainen. This system can cover almost a month of the small town's heating demands in summer and nearly a week in winter, cutting oil use.

Human sweat battery

Researchers at the University of California developed a bio-battery using lactate from human sweat. It could power wearable devices but is currently at the concept stage.

These innovations demonstrate diverse approaches to storing renewable energy, each with its own advantages and applications.