V2G - Vehicle to Grid

[eberrong]

Surely you have heard about this buzzword V2G regarding the next generation of plugin hybrids. Can anyone explain to me the benefits of this technology to the consumer? I work in the power plant industry and I can totally understand the benefit to the power companies. They get extra reserve power (to use as they please) without having to purchase more power plants. But for the consumer this means: having an unpredictable battery charge when you go to hop in your car and increased battery wear that you are not in control of. The only benefit that I can see is that if the power companies pay you more for the power that they remove from your battery than you paid to charge them in the first place. So far, I have not seen this point mentioned in any articles I have read on the topic. All articles seem to describe v2g is the greatest thing since sliced bread.

Also I have concerns that v2g is really going to cloud the picture for the typical American consumer. I think most consumers are very skeptical about regular hybrids...much less plug-in hybrids...much less v2g plug-in hybrids. Also I hope that the deployment of plug-in hybrids to the general public is not in any way delayed due to v2g.

Am I missing the point here? Please someone correct me if I am wrong.

[chogan]

I'd say you have it right. It's just another way to shave the daytime peak of electrical demand. As with any other approach to that, there are system benefits to reducing the peak demand for electrical generation and shifting that demand to nighttime. It's just a question of whether the cost of doing it with batteries makes sense, and whether you can afford to pay consumers for their trouble, enough so that they'll agree to do it.

Let me put the most positive spin on it. Imagine a world with lots of EVs (big batteries) not PHEVs (small batteries). So the typical driver doesn't drain the battery on a typical day.

Further, assume that these EVs all use batteries that typically last far longer than the car does. For example, the currently available Altairnano Li-ion batteries are supposed to last 20 years or 15,000 full discharge cycles -- longer than you'd expect a typical vehicle to last. Lets say the technology gets even better than what's currently available from Altairnano, so the car dies before the battery does.

(Those battery life claims are shown here:

http://www.altairnano.com/documents/..._Datasheet.pdf.

Of course, what I've just assumed is that the typical car on the typical day has lots of unused capacity lots of unused battery life. Under those conditions -- spare capacity, spare battery life -- then V2G might make a lot of sense. Even then, the question would be the cost of the infrastructure to support this method of peak shaving, versus alternatives.

Just to put that in perspective, if, by contrast, you had a bunch of lead-acid battery EVs with limited range, no, you'd be crazy to do V2G. As you point out, you'd strand motorists and kill batteries. But as the tech moves to what Altairnano can produce today, and better, V2G starts to make more sense. It's all just a question of getting the cost on those batteries down.