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

[FBaggins]

9. No... I mean actual supply/demand spikes.

On a small scale they aren't a big deal, but they add up.

I'll give you an example.

A common demand-management technique is to get homeowners to connect their electric hot water heater in such a way that the utility can turn it off if it needs to. That way, when demand peaks on a hot day in the summer, they can flatten the peak of demand and save money (passing some of the savings on to you to encourage participation in the plan). Most consumers never notice it happening because they use little hot water in the middle of the day and the insulation on the tank keeps the water hot for hours anyway (really over a day depending on the model and how hot you consider acceptable).

In this case, consider that many appliances (A/C, fridge, well/sump pump) have a spike in their current draw as they are starting up, but have much lower run rates. "Smart" controls on that battery can level out the demand from the home without a net draw on the battery. Connected to a smart grid, and it can do the same thing in the agregate for supply surges.

But I still don't see how depending on cars being plugged in is a smart architecture

Not on any particular car... but on cars in the agregate.

Not only is it a hostile act to take precious electrons out of my car battery,

Not at all. You would choose whether or not to participate (and to what extent) and would be compensated for it. Take that water heater example. As I remember it, you could save $5/month by just agreeing to make your unit available to the demand management program (this was several years ago). There are some programs that aren't even "smart"... they just turn of the water heater entirely from 7am to 11pm and saving $10-15/month. There are lots of people who would still never notice the difference.

if several of us happen not to be plugged in at that moment, it seems like that whole premise falls apart.

The system would need to be designed to account for cars being used as cars.

But the EVs of the future will likely be plugged in either at home or at work a very high percentage of the time. And, of course, that behavior can be modified with incentives funded by the savings they provide to the grid.

Another think that Kristopher had mentioned in the past is that EV batteries have value to the grid long after they are usefull in the car. The repurposing of those batteries in smarter homes or in bunches as grid storage can help make EVs affordable sooner and reduce the expense of grid storage.

The bottom line, as I see it, is that EVs are nowhere near being commercially viable at this point.

Of course not. But infrastructure planning is a game with a very long time horizon. They will someday be viable unless something better comes along.