Joshua Rhodes for Forbes:  Cheap energy storage, long hailed as renewable energy’s younger cousin that, once of age, would create a dynamic duo strong enough to upend the electricity system as we know it, got a steroid shot this week when FERC announced that it was going to let energy storage operate in the wholesale markets as both a buyer and a seller.

While this development plays to storage’s benefit, the market (at current prices) is still relatively small. For energy storage to make a big play, costs still needs to come down by about half, and the market itself might have to change.

In the U.S., most energy storage comes from pumped hydro facilities, but these systems require large amounts of co-located land, elevation and water. Batteries have been (or will be) built in both Texas and Arizona in order to defer expensive transmission line upgrades.

But battery prices are now declining to the point where they are starting to move into new markets. Tesla’s 100MW/129MWh battery in South Australia appears to be taking full advantage of market price fluctuations and helping the grid ride through multiple coal plant trips this (Australian) summer.  Full Article: