Heat/cold storage is very efficient when you have direct consumers for heating/cooling: charge the insulated tanks in times of electrical surplus, heat/cool whe

Heat/cold storage is very efficient when you have direct consumers for heating/cooling: charge the insulated tanks in times of electrical surplus, heat/cool when needed. Mixed application installations (e.g. campus-scale air conditioning and hot water, generously overprovisioned to allow some paid grid stabilization work on the side) might be an economic sweet spot even with terrible cycle efficiency. In any case, for grid storage, price per effective capacity will remain the key metric as long as the storage market is not saturated. Tanks scale pretty good.