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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."
Wait until everyone leaves on holiday some unusually hot 4th of July morning. The earlybirds are fine, but those leaving later have empty "tanks" because ConEd sucked out all their battery power to run all of the air conditioners.
AC Propulsion, who built the car, has been working on this technology for quite a long time. Their press release is at http://www.acpropulsion.com/releases/10-24-2007.htm. They also have a solar powered, unmanned aircraft, an electric sports car that long precedes the T-Zero, and good taste in car bodies since they've used the Sportech and xB for their major projects.
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 or a high-speed flywheel, 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)
If I have nothing to hide, don't search me
It's like a giant Carpacitor!!!
It's only really useful if it can store 8.6 jigawatts!
Probably lose 10% of power charging and 10% discharging if you are lucky. You want your car in the daytime when loads are heaviest. Must not put power on lines when linemen are working on them. Pumped hydroelectric is much better and currently used to store power. Always thought wind powered generators near a pumped hydroelectric would be a good thing. Also large windfarms in places like west Texas generating hydrogen would also be a reasonable thing to do. When we run out of natural gas, the existing gas distribution system could be used to pump the hydrogen all over the country much as we do with natural gas today.
Computer voice: "Sorry, you cannot go to Vegas this weekend, we need your batttery."
Table-ized A.I.
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.
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?
Umm... no? Right now, you can already do time of day metering, where you get charged different rates at different times. People with solar installations like this, because their solar panel returns power to the grid at daytime rates, and then they come home at night and use power at evening rates. You could do that with a battery too, except that batteries are expensive so no one does. Unless you already happen to have the battery...
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.
The brownouts we're mainly hot air. First off, very few actually happened. Secondly, they were artificial- caused by manipulations of the power grid by energy providers for profit. There was no energy shortage.
Bzzzt... Wrong.
The energy shortage was real and localized. In the Enron days, California capped electricity rates as a consumer protection move. As a result, Enron in a move to cut losses from expensive generation and as a leverage tool to negotiate new rates, took the oppertunity when fuel prices spiked to shut down a lot of ineffecient generation plants for maitenance. This was followed by a heat wave which put a spike in demand for AC. A line tripped offline. It was either blackout time as systems cascaded carrying the overload or simply drop part of the load and leave the rest of the sytem up.
http://tdworld.com/mag/power_world_technology_update_2/
"California Energy Crisis Reaches Stage Three Electrical Emergency Already under a Stage Three Electrical Emergency due to scant resources, the California Independent System Operator (California ISO) encountered a significant and sudden loss of transmission capacity Jan. 21, 2001, that forced municipal utilities in Northern California, U.S. to endure a brief 20-min transmission-related outage."
"The California ISO issued the controlled outage to keep the ac lines from overloading at Path 15, a group of high-voltage lines in central California already at their limit because of low resources in the northern part of the state."
There was a blackout because there was not enough in area generation online. The capacity of the system was stressed. A line failed. The already loaded lines couldn't take on the replacement load. Part of the area was shut off to preserve the remaining area. It was small blackout time of watch the entire area go dark as the system collapsed.
http://en.wikipedia.org/wiki/California_electricity_crisis
"Due to price controls, utility companies were paying more for electricity than they were allowed to charge customers forcing the bankruptcy of Pacific Gas and Electric and the public bail out of Southern California Edison. This led to a shortage in energy and therefore, blackouts. Rolling blackouts began in June 2000 and recurred several times in the following 12 months."
"Energy price regulation forced suppliers to ration their electricity supply rather than expand production. This scarcity created opportunities for market manipulation by energy speculators."
If you need any more proof that price controls cause shortages, just re-read the above. You can mandate $1/gallon for gasoline, but don't expect to find it for sale anywhere.
Read between the lines.. they didn't pay high prices for fuel for ineffecient plants.
"Despite the action, PG&E said it still is having trouble getting gas suppliers to comply with the emergency order originally issued January 19. PG&E has said it has enough gas in storage to make up for the lost supply under such a scenario until the first week in February. According to a company spokesperson, PG&E's storage currently is well below 50% full, or less than 16 Bcf and depleting rapidly by about 500 MMcf/d to 1 Bcf/d."
They used their reserve fuel, but could only buy fuel at a loss due to price caps and high fuel cost. Gas suppliers were not selling below market. They sold at market rates, a price the utilites could not afford.
Expensive to run generation plants were shut down for upgrades and maitenance while they waited out the high fuel prices. The spike in demand caused the inevetible. The lines into the area could provide only part of the cheaper power from elsewhere.
http://www.usbr.gov/dataweb/html/pninter.html This is the list of the lines from Oregon into California and their capacities.
The truth shall set you free!
This isn't about generating electricity at YOUR desire (or sun's desire or wind desire). What you propose is the PROBLEM for which the electric car's battery balancing is the SOLUTION.
The battery in the car will give energy back into the system WHEN THE ELECTRICITY IS NEEDED, not when you have some available.
In the electric grid there is a minimal, constant power needed - this is the baseline. Above this, the request fluctuates - with some slow gradients and some fast gradients.
Slow gradients are things like the move from evening to night (people go to sleep, lights go off, TVs go off). As people go to sleep from - let's say 9 PM to 12PM, there is a slow change in electricity need. "Baseload" power plants usually can change their output to account for this.
And there are fast gradients. Some of them are small, like an entire office building starting or shutting down their lights. Some, however, are not so small - like - let's say - an entire neighboorhood starting their electric boilers at the same time). When this happens, a brownout ensures - the electric plant is overwhelmed, and its output voltage drops. Having a lower voltage, the electric boilers will consume less power than at full voltage (Power is voltage squared demultiplied by resistance/impedance). However, some consumers (switching power supplies) will just take a higher amperage, and the voltage goes even lower.
For this kind of fast gradients, the gas turbines are used as "fast switching" sources. A gas turbine is able to ramp from - let's say 10% to 90% rated power - in the space of a couple of seconds (for comparation, a hydroelectric big plant will ramp the same in a couple of minutes or more). Ramping back might be even slower on baseload power plants (unless they choose to vent already heated steam). Yet, electricity generated from natural gas is expensive (much more so compared to coal or hydro). Also, the nuclear plants (while they might be able to ramp quickly on and off) are NOT designed to do so, and are not tested to do so. They are just slow-ramping, base line power plants.
As such, the electricity company hopes to supplement some of this "fast switching", expensive electricity with your car's battery.
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.
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Disclaimer: I worked on some of the software in the vehicle mentioned in the article. The article was a little light on technical details. Dr. Kempton is much more qualified to comment with respect to V2G technology, but I'll try to preemptively clear a few things up, here.
Why would I let the big bad utility company wear out my expensive battery?
Because they'd pay you more than enough to make it worthwhile. The details of the business model are undefined, but as TFA explains, there is a lot of money on the table (at least $4K/year), so there is considerable financial incentive to put a fleet of vehicles to use. The basic idea is that a vehicle owner would sign on with an aggregator, who would control a fleet (thousands or hundreds of thousands of vehicles) and sell regulation services to the utilities at the megawatt level. It could be that you'd lease your battery from the aggregator.
The most-valuable proposition is called ancillary services. Very simplistically, in this model you're not really moving much energy; you're really just selling the availability to provide fast-reacting regulation. Grid operation is a giant, complicated balancing act -- balancing generation with load.
Right now the balancing is done by ramping generator output up and down. As greater amounts of solar and wind make their way into the power mix, generators will end up doing even more regulation. Unfortunately, generators are generally least efficient and most polluting when ramping, so a fleet of vehicles that can provide small amounts of regulation within milliseconds is extremely attractive to grid operators.
But what if the utility company drains my battery when I need it for that long trip?
Obviously the system would have to be designed to take your individual driving needs into account. The good thing is that it doesn't really matter what you do as an individual -- the statistical behavior of the fleet as a whole remains predictable.
Furthermore, with a sufficiently large fleet of vehicles, it's possible to provide all the necessary regulation just by charging. If a vehicle is charging at 10kW, but is capable of charging at 20kW, then it can adjust its power up or down by 10kW, subject only to the constraint that it needs to be full by morning (or whenever). I've seen estimates by people more knowledgeable than I that we could regulate all of California with a fleet on the order of hundreds of thousands of EVs.
If you're doing all your regulation via charging, then you can't claim you're wearing out your battery prematurely (unless you were never planning to charge it again, of course).