Looks like another great way to use excess renewable power when the grid is underutilized but the wind is blowing and the sun is shining. Build enough of these to matter and you could probably get away with a fair bit less battery storage as long as you still have natural gas peakers.
It's not really all that conducive to starting and stopping depending on energy prices. We already have that same capability with Aluminum and I've never heard of any Aluminum plant shutting down during the day and picking back up at night. Those cells and keeping them running are going to be expensive enough that I doubt it would make economic sense to stop production unless power is just absurdly expensive. The price of iron isn't about to fall through the floor and the price of electricity isn't going to skyrocket so even if power was free all night I'm still not sure that it would be worth it to save a little on electricity costs in the day and miss out on a chunk of production.
I think the much bigger impact is going to come from deferred charging of battery electric vehicles. The transportation sector accounts for 28% of total US energy consumption. Electric cars are getting capacities large enough that range is close enough to on par with traditional ICE vehicles. It's already commonplace to shift around when you fill up at the gas station by a day or so, with electric vehicles rather than having to work around personal schedules to refill you can just leave it plugged in when parked at home and let it charge whenever it's appropriate so long as it meets basic constraints like e.g. make sure I have at least 60% charge by time to leave for work.
If a large portion of 28% of total energy demand can be deferred a bit that should do a lot to increase the flexibility of demand to accommodate the variability of renewable power sources. And that doesn't even touch on repurposing spare capacity as a distributed energy storage mechanism. If the margins of buying power at cheap costs and selling it at peak demand can more than pay for the degradation of the battery and any conversion inefficiencies then that's a ton of energy storage capacity right there. It already makes economic sense for utilities to use some battery energy storage systems today so I can't imagine it would be impractical when the capital costs are reduced to nothing and it's just the operational costs to consider.
Haha, I didn't notice that actually. The presentation I saw was last year by some folks researching the topic who found a way to make it economical enough.
I could have sworn the name was the one I thought but guess I am too old to have a good memory =)
