Sand batteries are a similar concept, with the advantage of being able to store at over 100°C. I believe they can store heat for months. https://polarnightener

Sand batteries are a similar concept, with the advantage of being able to store at over 100°C. I believe they can store heat for months. https://polarnightenergy.com/news/worlds-largest-sand-battery-now-in-operation/ https://polarnightenergy.com/news/worlds-largest-sand-batter...