This is pretty interesting, but not the sort of $s I expect will be enough to make a difference.
The economics of energy storage are pretty interesting, and not entirely related to the penetration of renewables. Energy storage already exists in the Australian network; look up the Bendeela Pondage as an example. Leaving aside the corporate objectives for the site, this sort of energy storage is designed to cover the gap when demand changes faster than generation can. So in a grid with lots of coal plants, the classic ‘baseload’ plant can’t move its load quite as quickly as demand can change. Something quick to switch on like hydro, can cover this shortfall.
Interest in storage has increased dramatically in recent years, mostly because of the obvious link to renewables. But as you can see from above, storage is also necessary when network demand changes rapidly. I’ve mentioned in other posts the link between demand and air-conditioning use, and they impact that has on the network. Good energy storage could help smooth these peaks and troughs, decreasing the need network upgrades.
We’ll see though; most of the most promising energy storage technologies at the moment are relatively expensive or in the case of pumped-hydro, severely limited by the availability of suitable geography.
For more information on energy storage, the Energy Storage Association in the US is an excellent place to start.