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Your Future Home Might Be Powered By Car Batteries (bloomberg.com)
Increasingly utilities and automakers are wondering if they could use the batteries inside electric cars as storage for the entire public power grid. An anonymous reader shares a report: The idea, known as "vehicle-to-grid," is to someday have millions of drivers become mini electricity traders, charging up when rates are cheap and pumping energy back into the grid during peak hours or when the sun simply isn't shining. If it works -- and it's a big if -- renewable energy could get much cheaper and more widely used. "We really, really need storage in order to make better use of wind and solar power, and electric cars could provide it," said Daniel Brenden, an analyst who studies the electricity market at BMI Research in London. "The potential is so huge." Today, fewer than one percent of the world's vehicles are electric, but by 2040 more than half of all new cars will run on the same juice as televisions, computers and hair dryers, according to estimates by Bloomberg New Energy Finance. Once cars and everything else are fed from the same source, they can share the same plumbing.
The Powerwall costs extra money, but you will already have your car battery, so there is no additional capital cost other than an inverter.
My wife has a Tesla with a 240 mile range, and on 95% of days she uses less than 20% of the capacity. The rest could be available for energy price arbitrage.
The car starts charging at 2 am, when electricity prices are lowest. The power companies need to fill the gap from 4pm to 7pm when power use peaks, but solar is fading.
(Disclaimer: EV owner, researcher in relevant field, and I was once asked to evaluate a research project on V2G in an European country)
The idea is interesting, and may well have an impact in countries with a lot of non-controllable power (wind, sun, but to a degree nuclear and other baseloads too), if price oscillations are large enough. The article mentions a potential of USD 40 a month, which is just above a buck a day. Would you risk not having enough charge in your car to get home for such a pittance?
More importantly, there is no mention of battery wear. Batteries are much more expensive than the energy they store through their lifetime. Teslas have actually a very limited lifetime of about 500 cycles (since the batteries are large, there is no need for more lifetime—it's actually smart to use short-lived, cheaper NCA batteries as Tesla does), which means that, if you assume USD 200 / kWh by 2030, each kWh will cost 40 cents only in battery depreciation: that's a lot more than what the energy costs, and will likely more than offset those 40 USD a month. (Yes, there are longer-lived batteries; they are also more expensive) (Yes, battery wear is not just a matter of cycling, it's also storing at high voltage, rate of charge/discharge at which temperature, and lots of other things)
V2G is very interesting for grid companies as a solution to their energy storage problems, but they seem to intend to exploit the lack of consumer understanding of EV cost dynamics: the real cost of a kWh is the battery wear, not the actual energy. There is a reason why these companies are not buying the batteries directly.
I believe V2G has more potential in "private grid" applications: e.g. if you have a cabin in the woods with no option of grid connection, you could drive to it with you EV and power it from your batteries while you are there (a home uses a lot less power than a car); or you could transfer some charge to a vehicle that ran out of it on the road (actually the Toyota Mirai has a similar feature, a ChaDeMo outlet).
Victims of 9/11: <3000. Traffic in the US: >30,000/y
A lot of pure EVs store significantly more power than the average home uses in a day so there's a good chance it can be used to store renewable energy. Even if people can't get renewable power, they're valuable for levelling power use. Part of what keeps electricity costs high is that our power use swings wildly during the day so power systems need to be designed to generate more power than will ever be used.
Also most EV's use the much more reliable LIthium-Iron-Phosphate class batteries (https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery) which wear out at a much slower rate than most lithiums and rarely if ever catch on fire. Tesla I believe doesn't use these more reliable batteries but the trade-off is the ability to pack more power in a smaller space / weight which is why they have some of the smallest batteries for their incredible capacity on the market.