New (Flow) Battery Design Could Help Solar and Wind Energy Power the Grid

[FBaggins]

7. "Drain EVs" dramatically oversimplifies the proposal.

There are three critical challenges to the variability of some renewables. One is what you're addressing... the fact that the grid can go for extended periods of time (occasionally days) with little to no generation from those sources. EVs won't do much to help that (though I could imagine a use in my home). It wouldn't make sense to have a system that could result in the owner waking up in the morning and not being able to get to work.

But that's not really how they expect this to work.

The second challenge is the mirror of the first. Sometimes they produce "too much" power and the grid operator has to do something with it while they adjust more controllable output. EVs combined with a smarter grid could fill that demand as they charge on power that would be incredibly cheap (since it would otherwise be thrown away). Both the consumer and the grid operator benefit.

But that too is only a small part of it.

The third challenge is that this variability is not day by day or hour by hour. It's a constant fluctuation that gets more and more challenging to manage as variable sources increase their penetration in the market. This is on top of the already existing challenge of the momentary fluctuations on the demand side as well.

This is where I think V2G solutions really could shine. They could go a long way toward smoothing that instantaneous variability (on both the supply and demand side)... and they can do so without any risk to your morning commute. I would imagine utilities offering you a guarantee that they will charge the vehicle when supply is cheap and only drain down to a given point (say, 90% full). This would allow them to not only increase the penetration of renewables generation, but also keep prices down by avoiding the most expensive peaking power costs - all without extreme expense for grid-scale storage.

This would, of course, require a significant market penetration of EVs as well as a much smarter grid, but there are synergies there that make it very attractive.