In Finland, engineers have created a groundbreaking sand battery that could revolutionize renewable energy storage. The system uses ordinary sand, heated to over 500°C (932°F), to store excess energy from wind and solar sources. This stored heat can be released months later to generate electricity or provide district heating — keeping homes warm and lights on even during Finland’s long, dark winters. Unlike lithium-ion batteries, the sand battery doesn’t rely on rare minerals, doesn’t...
