Could Sand Be the Next Lithium? Searching for Better Renewable Energy-Storing Batteries

"The green energy revolution still faces a huge obstacle: a lack of long-term, cost-efficient renewable storage," writes the Washington Post. But then they check in on a Finnish start-up running the world's first commercial-scale sand battery, which uses solar panels and wind turbines to heat sand-filled vats (up to 1,000 degrees) to back up district heating networks:The sand can hold onto the power for weeks or months at a time - a clear advantage over the lithium ion battery, the giant of today's battery market, which usually can hold energy for only a number of hours. Unlike fossil fuels, which can be easily transported and stored, solar and wind supplies fluctuate. Most of the renewable power that isn't used immediately is lost. The solution is storage innovation, many industry experts agree. In addition to their limited capacity, lithium ion batteries, which are used to power everything from mobile phones to laptops to electric vehicles, tend to fade with every recharge and are highly flammable, resulting in a growing number of deadly fires across the world. The extraction of cobalt, the lucrative raw material used in lithium ion batteries, also relies on child labor. U.N. agencies have estimated that 40,000 boys and girls work in the industry, with few safety measures and paltry compensation. These serious environmental and human rights challenges pose a problem for the electric vehicle industry, which requires a huge supply of critical minerals. So investors are now pouring money into even bigger battery ventures. More than $900 million has been invested in clean storage technologies since 2021, up from $360 million the year before, according to the Long Duration Energy Storage Council, an organization launched after that year's U.N. climate conference to oversee the world's decarbonization. The group predicts that by 2040, large-scale, renewable energy storage investments could reach $3 trillion. That includes efforts to turn natural materials into batteries. Once-obscure start-ups, experimenting with once-humble commodities, are suddenly receiving millions in government and private funding. There's the multi-megawatt CO2 battery in Sardinia, a rock-based storage system in Tuscany, and a Swiss company that's moving massive bricks along a 230-foot tall building to store and generate renewable energy. One Danish battery start-up, which stores energy from molten salt, is sketching out plans to deploy power plants in decommissioned coal mines across three continents... But in order to succeed, natural batteries will need to provide the same kind of steady power as fossil fuels, at scale. Whether that can be achieved remains to be seen, say energy experts. And the industry may be subject to the same pitfalls that loom over the renewables energy sector at large: Projects will need to be constructed from scratch, and they might only be adopted in developed countries that can afford such experimentation. Lovschall-Jensen, the CEO of a Danish molten salt-based storage start-up called Hyme, says the challenge will be maintaining the same standards to which the modern world has become accustomed: receiving power, on demand, with the flip of a switch. He believes that natural batteries, though still in their infancy, can serve that goal.

Read more of this story at Slashdot.