Comment by pfdietz

There's also very interesting work on non-battery storage technology. The one that has gotten my attention is Standard Thermal's "hot dirt" thermal storage technology. I don't know where they are in crossing the chasm on this, but the theory looks very promising, with capex as low as $0.10 per kWh of thermal storage capacity. This promises to make 600 C heat available 365/7/24 for a cost as low as $3/GJ, similar to heat from combustion of Henry Hub natural gas.