from the the-grid-is-fine-but-my-car-won't-go dept.
phys.org has an article on a study which investigates the improved stability that electric vehicles bring to the power grid.
Several recent studies have shown that plug-in electric vehicles (PEVs) operating as vehicle-to-grid (V2G) devices can offer advantages for the grid such as backup power for renewable energy sources, power regulation, and load balancing.
Now in a new study, researchers have found another potential advantage of using PEVs as sources of power for the grid: they can improve stability when the grid is subjected to large disturbances
This study appears to look at a two way communication mechanism between the grid and vehicles using low latency ethernet links to control power consumption - Vehicles can consume when there is surplus power, but can react to shortages by feeding return power back into the grid.
The results of the simulations show that PEVs can improve stability in two ways. First, they can reduce the speed and voltage fluctuations resulting from large disturbances by up to 80%. And second, they can extend the critical clearing times (after which the system will be unable to resume stable operation) by 20-40%. In general, the PEVs can begin to stabilize the grid within seconds of a large disturbance
The paper, published in the New Journal of Physics, is available for download.
(Score: 3, Insightful) by frojack on Tuesday November 25 2014, @08:59PM
Placing large batteries around the grid for stability, and short-term back-filling of capacity temporarily unavailable is all fine and dandy, and maybe a good idea.
But draining my EV car battery just before I need it is hardly acceptable. Its like solving an oil shortage by siphoning everyone's gas tank.
No, you are mistaken. I've always had this sig.
(Score: -1) by Anonymous Coward on Tuesday November 25 2014, @09:22PM
I also have the image of someone:
"I have to go on a long trip, might as well fill up before I go"
*the power company has decided they need the excess power of your vehicle, citizen*
"darn"
I also love the idea of power-stealing:
1 - Set up a small microcontroller and power outlet near your shop
2 - Transfer 80% of battery life from every vehicle which plugs in to your (dis)"charging station".
3 - Skip to 4
4 - Free power, donated from 'the greenies'.
(Score: 2, Insightful) by Anonymous Coward on Tuesday November 25 2014, @09:25PM
> But draining my EV car battery just before I need it is hardly acceptable. Its like solving an oil shortage by siphoning everyone's gas tank.
Because no one would ever think of that when designing a system like this. These guys are idiots for not realizing that was an unsolvable problem. If only frojack had been on the peer review committee for this mickey-mouse paper, it would have never made it to publication. Good thing we have him here to tell it like it is!
(Score: 0) by Anonymous Coward on Tuesday November 25 2014, @09:38PM
I believe that the GP poster as made a contribution to the discussion of utilizing this technology in a semi-comical manner.
I do not believe that you have done the same.
(Score: 1, Insightful) by Anonymous Coward on Tuesday November 25 2014, @09:58PM
Hhhm, so its OK for one poster to call someone an idiot using snark but not OK for another poster to call the original poster an idiot using snark.
Seems kind of tribal on your part.
(Score: 3, Insightful) by choose another one on Tuesday November 25 2014, @10:10PM
Well actually it seems the paper does not consider it at all... mostly I suspect because they are focusing on controlling very short term transients.
They do allude to some of the bigger issues, one being that it will use up battery charge/discharge cycles, which may be even more of an issue. Be interesting to see how that interacts with any warranty on the vehicle. Secondly their scheme needs low latency gigabit ethernet to each vehicle when it's plugged in, presumably often at home, which could be great news except they seem to omit to mention any political or legal obstacles that incumbent broadband suppliers might raise to the provision of gigabit connections to every home...
For longer / larger grid variation I suspect the work they reference on variable pricing will be more relevant - I don't see variable pricing reacting in the timescales of this scheme but it would handle the windless night plus power station fire scenario. In short, you'll still be able to get to work in the morning if the grid has a bad night, but you better enjoy the drive because your effective fuel cost will be up with the Ferraris.
(Score: 0) by Anonymous Coward on Tuesday November 25 2014, @11:53PM
You seem to be arguing that this narrowly focused technical paper is valueless because it doesn't address all of the issues required for a full-scale system implementation.
I do not understand that attitude, I do not see what value it adds to the discussion to assume that anyone taking the scope beyond that of this paper would do so in the stupidest possible way.
(Score: 2) by sjames on Wednesday November 26 2014, @11:53PM
A better answer would be to have the cars just suspend charging when the load spikes. It wouldn't provide as much benefit, but would be beneficial without battery wear.
(Score: 1) by GWRedDragon on Tuesday November 25 2014, @09:52PM
>> But draining my EV car battery just before I need it is hardly acceptable. Its like solving an oil shortage by siphoning everyone's gas tank.
Don't worry, problems like this are easily solved! They'll just hardcode it to make sure the battery is filled by 7am the next morning, because surely nobody will want to drive their car at 3am. "It's fine, our solution works for 98% of users!"
[Insert witty message here]
(Score: 4, Informative) by TrumpetPower! on Tuesday November 25 2014, @09:53PM
They're not even remotely considering draining the batteries, just drawing a small load for a few minutes at a time to stabilize the grid when something happens to a generating substation somewhere and until a backup substation can kick in. Those things don't have instant response / power-on times, but vehicle batteries most certainly do.
And they describe a system where the vehicle has an high-speed data connection to the grid operators as being essential to how it's supposed to work. That means your car gets to make the decision as to whether or not it'll supply power back to the grid. That, in turn, means that your car isn't going to do that if it doesn't have enough charge to do so -- and, similarly, that you, yourself, will be able to decide how much is enough.
I imagine most people will be quite happy to grant the utility up to 15% - 20% of their battery capacity on demand in exchange for some sort of financial compensation. And, yes, if you've got some big trip planned for the next day that you really need that extra bit of charge, you'll be able to set an override.
b&
All but God can prove this sentence true.
(Score: 3, Insightful) by frojack on Tuesday November 25 2014, @10:10PM
The article further states that EVs can deliver electricity to the grid at a RATE of 10KW (which is not a rate).
Virtually all home charging stations are 30 amp at 240 volts which is 7.2KW, and all of them are required to isolate the house panel (and hence the grid) against backfeed.
So there is a bit of an infrastructure problem to overcome.
As for the few minutes claim, that's not all that believable either. When it comes to spooling up another gas plant to handle the evening cooking load the temptation would be to delay that as long as possible, (and they take 30 minutes to come on line even if they run pre-heat). And if they get away with that, why build another gas plant when they can satisfy peak demands with parked cars?
They may sell it as 3 minutes, but that is not how these things actually happen in the real world. You can't keep your doctor even if you like your doctor.
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Wednesday November 26 2014, @04:36AM
10KW (which is not a rate)
From the 'kipedia [wikipedia.org], emphasis mine:
(Score: 1) by m2o2r2g2 on Tuesday November 25 2014, @10:28PM
So because your car has connectivity, you the end user have complete control over it? The car company does not decide these rules for you? And every big company always make decisions with the interests of their customers in mind?
Wow. Where can I buy more belongings like that?
(Score: 1) by m2o2r2g2 on Tuesday November 25 2014, @10:45PM
Many people have shouted parent down (even though an identical comment further down was not marked troll!)
Mod them up.
RTFA does not consider impact on car battery. It is looking at this from one perspective only. This counter-point is valid. If there are not protestations from the end users, they will not be thought of and accordingly worked with or compensated. Current infrastructure (thanks to subsidised solar) is trending toward one rate for supply and another for feeding back into the grid. How happy would you be if you had to fill your tank at $2 per litre (or 2 score $ per hogshead or whatever other imperial units you use) but then the petrol company needed some back and only gave you $0.5 per litre back, or if they don't mandate 2 way monitoring you get nothing back.
Also there are regulations in place about backflow that need to be wiped out. There is the compensation for extra wear on your battery issue.
There are many problems not addressed (because comprehensive analysis is harder than "this simple idea will solve all the world's problems" papers)
(Score: 0) by Anonymous Coward on Wednesday November 26 2014, @03:30AM
> If there are not protestations from the end users, they will not be thought of and accordingly worked with or compensated.
Where does that idea come from? What kind of perspective does it take to think that such an obvious issue would not be considered during design and specification phases? You might have a point if we were talking about non-obvious corner cases that have unanticipated interactions and cascade effects , but what does it take to think that something so obvious that a first post on some obscure news aggregation blog could figure it out but that actual engineers who do this work for a living, who themselves almost certainly have to drive to and from work, would ignore it?
I am generally curious here, explain yourself.
(Score: 2) by Arik on Tuesday November 25 2014, @09:44PM
But these should be dedicated batteries for this purpose - house batteries. Trying to stack another use on top of the car battery sounds like a remarkably bad idea. Need to take the car? Too bad. It's a heavy usage time, the battery is dead. Try again later after it's had time to charge.
If laughter is the best medicine, who are the best doctors?
(Score: 2) by tibman on Tuesday November 25 2014, @09:50PM
If people get battery systems then they might as well get solar to charge it. Which means the power company is making less money. But yes, it would be a stabilizer : )
SN won't survive on lurkers alone. Write comments.
(Score: 3, Informative) by frojack on Tuesday November 25 2014, @11:04PM
This has nothing to do with electric vehicles. It's about batteries.
It has everything to do with electric vehicles. RTFA before making such a claim.
They are going to let every vehicle owner finance their surge capacity and load stabilizer systems.
House batteries exist in a vanishingly small number of house. EVs are starting to appear in
increasing numbers. 2% of all vehicles by 2020, so 2 out of every 100 houses will have
and EV in the garage. When you consider 56% [ornl.gov] of households have multiple cars, the numbers suggest something closer to 3 houses out of 100.
Percent of households with battery banks?
Most places its zero. Even in Hawaii with its 4% photo-voltaic penetration, household batteries aren't common. Rooftop solar is used to heat water, or feed the grid, but almost nobody is storing in battery banks.
A car gets maintenance. People take it in to the shop once in a while. Batteries in houses? Joe Sixpack is never going to look at them.
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Tuesday November 25 2014, @11:57PM
In 10 years there are going to be a lot of discarded electric car batteries with 50%+ capacity remaining.
Those would be ideal for use as storage in the home.
Maintenance on them is no big deal, people typically have furnace and/or AC maintenance once a year, doing a battery check as part of that visit would be a natural outgrowth.