Electric Cars to Help Utilities Load Balance Grid

Reservoir Hill writes "A team at the University of Delaware has created a system that enables vehicles to not only run on electricity alone, but also to generate revenue by storing and providing electricity for utilities. The technology, known as V2G, for vehicle-to-grid, lets electricity flow from the car's battery to power lines and back. When the car is in the V2G setting, the battery's charge goes up or down depending on the needs of the grid operator, which sometimes must store surplus power and other times requires extra power to respond to surges in usage. The ability of the V2G car's battery to act like a sponge provides a solution for utilities, which pay millions to generating stations that help balance the grid."

Battery Life?

[corsec67]

Most batteries have a nominal number of charge/discharge cycles that they can go through before they can't hold any capacity any more.
Why would you wear out an expensive, hard to dispose of part of a car like that?

(Unless the cars use Supercapacitors [wikipedia.org] or a high-speed flywheel [wikipedia.org], in which case the only issue is transformer/inverter losses, which might be balanced by transmission losses if the usage is near to the car, in which case this could be a good idea)

Re:will never work

[myrdos2]

To my mind, the serious flaw here is that the highest cost of running an electric car is having to periodically replace the batteries. If you talk to the owners of lead-acid battery cars, they'll tell you they replace them an average of once per year. These things are only good for a few hundred deep-discharge/recharge cycles.

Of course, the electric company might not deep-discharge your batteries, but they're still wearing them out. The battery is the weakest part of an electric car. Expensive and barely adequate to move you around. I'd prefer to wait until my battery's capacity had dropped below the point of being usable, and then let them store power in it while I buy myself a new one.

Re:will never work

[calebt3]

Hence the Ultracapacitors [slashdot.org]

Re:Battery Life?

[Leuf]

If it were actually economical to do this, then why wouldn't the utilities just buy the batteries themselves rather than pay you to use yours?

Re:Better ways to balance load

[edwardpickman]

Natural gas lines are't suitable for hydrogen. It's the smallest atom so it tends to leak from most any seal. Part of the problem with hydrogen is storage and distribution because of leakage. If you leavea full tank of gasoline for a year it's still full. Even the best hydrogen car storage system would be empty long before the year is out. If you are driving constantly the loss would be manageable but even leaving it overnight would result in some loss and a weekend might see a noticeable drop in tank pressure. I love hydrogen but it seems best suited for short term storage and it's strictly a storage medium and not a true power source. I think it's better suited to home storage system of power for solar and wind and recharging electric cars. Even the hydrogen cars that are being proposed are in truth electric cars they just use hydrogen instead of batteries. I've never heard of a hydrogen car getting 200+ miles on a tank like some of the latest electric cars using batteries. Recharge times are the biggest problem but that's strictly for long range travel since most people see home recharging as a plus with electrics. Capacitors may eventually solve this problem. Either way electrics if the cost of batteries came down would still work for 90% of the driving and even at current prices they are radically cheaper than hydrogen fuel cells. Platnium is going to keep the costs high. Electric is practical today and works with or current infrastructure. People complain about costs and range on electric cars I can't see them accepting hydrogen cars that cost many times as much and have a range of a 100 miles. Nano processes may drop the amount of platium needed but it will still be expensive and the storage problems still exist. You still need an energy source to produce hydrogen so there is no real difference between it and electric cars.

Offloading costs more like it.

[SeaFox]

The ability of the V2G car's battery to act like a sponge provides a solution for utilities, which pay millions to generating stations that help balance the grid.

So since I'm now taking over that job, how much will my cut be?

I thought so.

And this wont have any impact on the life span of my car's expensive battery will it?

Oh, it will.

Well since they're now saving so much money, they'll be able to lower utility ra---
What's so funny?

Yeah. Right. Sure.

[mbstone]

So the electric co. will buy the electricity in your car battery (at wholesale prices). Then when it doesn't need the power anyore, it recharges your battery (for which you are billed retail). Do this several dozen times a day and watch your bill skyrocket.

Re:Battery Life?

[evanbd]

Well, if it's not economical to buy the battery for the purpose, but you're going to buy the battery anyway to use it in the car... A lot of batteries (especially LiIon) have a significant component of their lifetime measured in years of service, not charge cycles. So if it's not costing you anything to use the battery like this, and you already own it...

Re:will never work

[fractalVisionz]

It will never work not because of the fact that the energy conversion isn't this or that, it will never work because nobody would ever want their car half full, or less, right as they are about to head out on a long trip. Long trip by todays electric standards is about 150-200 miles also.

Re:Better ways to balance load

[Nqdiddles]

Well, I don't actually need my car ALL day. I've seen scenarios described where the vehicles could be plugged in at home, then again at work (while you're in the office and not using it).
Planning the controls on the system would require a fair bit of effort/balancing, but it could be worth a look.
If perhaps the manufacturer (or power company, or someone else)"leased" the batteries to you, or otherwise minimised the effect of the increased use on your hip pocket, and allowed for user customisable minimum charge limits for letting it flow back onto the grid... I'm sure I can think of situations where I would be willing to try it.
I use my car for 30 minutes in the morning, and 30 minutes at night, during the week. Give me an incentive, financial or otherwise, without noticeable drawbacks, and I'd probably be happy to let them make use of my battery.
Getting this sort of system to the point where it actually made a difference (ie. enough of these cars in use) would be quite a challenge though.

Re:will never work

[evilviper]

it will never work because nobody would ever want their car half full, or less, right as they are about to head out on a long trip.

When you're planning on a car trip, you SHUT OFF this V2G mode, and put it on the normal charging cycle.

The other 99% of the time, when you need less than half the range to get you through the day, you leave it to charge in V2G mode, and potentially make some money while it's sitting there. It's not an issue.

The only issue is the lifetime of the batteries and converters, and the amount of money the power companies are going to pay participants for providing the service.

Though, peak metering would serve the same purpose better, and once there are a significant number of electric vehicles, the off-peak loads will be high enough to make it economical to just build more power plants, and run them at max capacity 24 hours a day.

Re:Make money from your car?

[Anonymous Coward]

So had the plants which were shut down 'for maintenance' not been shut down, there would have been adequate supply. They were all magically shut down at the same time because they were inefficient and the power companies didn't like running inefficient plants on expensive fuel.

So, in conclusion, the GP was right, but looking from a different angle.

Re:will never work

[Calinous]

"When you're planning on a car trip, you SHUT OFF this V2G mode, and put it on the normal charging cycle.
"
This bets against the consumer's laziness, and as such is a hopeless measure.

Re:will never work

[sean1279]

So are you telling me I replace my batteries every year? Try 3 years, mister. The battery is the weakest part of the electric car because your perception that electric cars should go cross country is flawed. I rarely need to travel more than 50 miles in a day.

Re:Make money from your car?

[darthflo]

Well, what's wrong with having your own private grid?

Not gonna happen in the next few years. Especially in the U.S., energy prices are ridiculously low thanks to the economies of scale kicking in. To truly live off grid, investments in the (lots of) tens to hundreds of thousands are necessary; the typical break-even for "private" type generators seems to be in the order of 10+ years; quite a bit out of reach for the average consumer.
If you really care about the stability of your power, some UPS kind of installation is, of course, possible. On its own this will ensure short-term stability, augmented with an own diesel generator you could bridge blacked out days or even weeks, datacentre- or hospital-style. It's somewhat of an own private grid but most people find a nice stack of hundred-dollar bills a lot more attractive than 99.99% instead of 99.5% or even 98% of power.

V2G is somewhat of a combination of this UPS idea with typical griddedness. Given the (gradually more-or-less forced) switch to electric cars, it'll be a few bucks saved without (much of) an investment to many. Given enough users, it could very well turn into a great way to cheaply turn the grid into a large-scale UPS. Implemented correctly this might not only balance out spikes extremely fast and on location but keep whole blocks powered even in worst-case situations without any connection of those blocks to the outside grid.