Haley Zaremba Haley Zaremba is a writer and journalist based in Mexico City. She has extensive experience writing and editing environmental features, travel pieces, local news in the… More Info Premium Content By Haley Zaremba – Jul 22, 2025, 4:00 PM CDT Finland has deployed the world’s largest sand battery, which uses heated sand to store thermal energy for district heating and industrial use, significantly cutting emissions. Sand batteries offer a cost-effective and efficient al...