And pure thermal uses are not good storage for high-grade energy forms, e.g. electric, because of conversion losses. In Norway, pumped hydro is a good place to

And pure thermal uses are not good storage for high-grade energy forms, e.g. electric, because of conversion losses. In Norway, pumped hydro is a good place to park high-grade energy. That said, for rarely drawn-upon storage, conversion efficiency doesn't matter very much. It is why back when hydrogen electrolysis still lost 40% off the top, it was considered fine for long-term storage. Now that it has exceeded 90%, it is useful in more places.