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Electric Cars Won't Strain the Power Grid
thecarchik writes "Last week's heat wave prompted another eruption of that perennial question: Won't electric cars that recharge from grid power overload the nation's electricity system? The short answer is no. A comprehensive and wide-ranging two-volume study from 2007, Environmental Assessment of Plug-In Hybrid Vehicles, looked at the impact of plug-in vehicles on the US electrical grid. It also analyzed the 'wells-to-wheels' carbon emissions of plug-ins versus gasoline cars. The load of one plug-in recharging (about 2 kilowatts) is roughly the same as that of four or five plasma television sets. Plasma TVs hardly brought worries about grid crashes."
...most people buy electric SUV's? Didn't think that one through, did they? :P
I read TFA and all I got was this lousy cookie
Being in that particular biz, I can say I am not concerned about it. Most of our power goes to industrial loads anyway. Joe Consumer is only a real concern to us on those hot mid July afternoons when he is at work running his air conditioner at the same time as the thirty million others Joes. Now, if they were to ALL buy electric vehicles and charge them in the afternoon in the middle of the summer while at work.. hah well, I think the major load on the charging systems would either be early morning when you just get to work and plug in, or early evening when you just get home and plug in. Not exactly prime time for brown outs..
"Computers are a lot like Air Conditioners" "They both work great until you start opening Windows"
The more uses of electricity we have that can be done "whenever", the better the future looks for power sources like wind and solar. Hopefully power companies will start charging different rates for on-peak and off-peak residential usage (like they already do for major industrial users), and the market will take care of it.
I admit I didn't have time to read the study thoroughly, but:
(a) The study specifically talks about hybrid cars, not pure electrics; the headline is misleading.
(b) Let's take a very conservative estimate and say an electric car draws an average of 10hp when driving. That's about 7.5kw. Let's round that up to 8 for simplicity's sake, and if we assume 100% efficiency, the car needs to spend 4 minutes on the charger for every 1 minute it spends on the road. If we charge it overnight (8 hours), that's 2 hours of driving time, or 60 miles if you average (as many drivers do) somewhere around 30mph - before you have to plug it back in for another 8 hours. And that's in the absolutely best case.
I might be missing something, but 2kw to charge sounds very unrealistic to me.
Yes but plasma TVs replaced CRT TVs.
And I expect there was a rather large switch from incandescent to compact fluorescent globes around the same time - which may have given greater savings than losses from those plasmas....
But what on earth kind of argument is that? Electric cars wont be a problem coz plasma TVs weren't.... How absurd.
Never happened. True story.
If the electric cars go home and charge at night, no, they won't strain the grid. Power is overproduced at night (you actually can't spin down the generators all the way, so they produce power even if nobody wants it.)
If they decide to charge during the day (for example, if people charge them at work), it could strain the grid. Particularly if they charge during hot summer afternoons.
Unless a significant part of the grid goes to solar, which produces the highest power during the daytime at summer, of course.
http://www.geoffreylandis.com
Probably because households buying plasma televisions purchase one, maybe two, and they are replacing cathode tube (with shadow mask) televisions which have been consuming electric load since the 1950s. And those plasma TVs are not operating for too many hours (hopefully), never mind that LCD televisions are far more popular. It's not surprising that many people are at least more concerned when typical two-car households each might add the equivalent of 8 to 10 plasma televisions of net new electricity consumption to the grid. Thankfully that consumption should be off-peak, especially if timed chargers and peak electricity pricing are mandated, but the plasma TV analogy breaks down very quickly.
I think there are roughly 2 houses on my block (of about 20 homes) that have a single plasma TV. They do, however, have at least a single car. Many of them have 2 or more. That translates as a lot of "plasma TVs" on that block.
Also, we need to realize that they are limiting their expectations:
Basically they are saying "Electric cars wont bring down the grid -- if they aren't widely adopted". What if, instead of half a million, there's 10-30 million? How many "plasma TVs" does it take to bring down the grid? Add to this that our current administration wants to increase the cost of our energy -- so not only will gas be more expensive, but so will electricity. What's the incentive?
Just like most working people, the first thing I always do when I get home is turn on my 4 or 5 plasma TVs. Since that wasn't a problem, I'm sure the electric car I buy won't be a problem either!
It may very well not be a problem, but that statement is goddamn stupid. Most of us aren't drawing that much power regularly when you get home.
Breaking Into the Industry - A development log about starting a game studio.
http://en.wikipedia.org/wiki/Rolling_blackout
Though the term did not enter popular use in the U.S. until the California electricity crisis of the early 2000s, outages had indeed occurred previously. The outages were almost always triggered by unusually hot temperatures during the summer, which causes a surge in demand due to heavy use of air conditioning. However, in 2004, taped conversations of Enron traders became public showing that traders were purposely manipulating the supply of electricity, in order to raise energy prices.
The DoE has stated that most of the Eastern Seaboard could support the energy requirements of every single car used for commuting today, without any changes to transmission or power production, as long as the cars are charged at night.
http://www.greencarcongress.com/2006/12/doe_study_offpe.html
What a great idea. And they could market it under a clever name like "time-of-use"or something equally catchy.
After we roll out the http://en.wikipedia.org/wiki/Vehicle-to-grid/ and http://en.wikipedia.org/wiki/Smart_grid/ and technology, then electric car owners will be able to sell their power back to the grid during peak usage to prevent blackouts, then recharge their car at night. Everyone wins - the owners electric bill is reduced, the utility avoids a blackout, and everyone else enjoys their AC. So - how many electric cars would it have taken to prevent the Enron blackouts?
The load of one plug-in recharging (about 2 kilowatts) is roughly the same as that of four or five plasma television sets.
Sorry, I don't understand this idea of power rated by plasma TVs. Could you please give that in terms of the number of slow cookers required to have the same draw as one EV charge?
Ask me about repetitive DNA
In future, it won't be enough to let a consumer make the decision on when to consume and encourage him with discounts in low peak hours. The model should be that for those loads where "time doesn't matter" we (the consumer) can indicate our constraints and then the electricity company will work within those boundaries. Of course, the more lenient the consumer is, the better rate he gets.
For this example, if I park my car at the office I don't care if the battery gets reloaded at 11 am of after lunch. As long as it's done before I drive home at 5 PM. Same for the return trip, the car could be rechared at 11PM or at 3AM, I don't care.
The crucial thing here is that fore heavier, but also time independent loads like this, your utility company gets control over when you are using electricity. We're still quite a bit away from that, but with smart grids, that's the way we're going.
And it will all benefit green power that produces electricity at "unexpected moments".
Browsers shouldn't have a back button!! It's all about going forward...
Tesla range: 160-250 miles (depending on options)
Subaru G4e range*: 125 miles
Mini Electric: 100 miles
Chevy volt: 40 miles
Coda Sedan: 90 miles
Nissan Leaf: 100 miles
*vehicle has not hit production yet
The ______ Agenda
In future, it won't be enough to let a consumer make the decision on when to consume and encourage him with discounts in low peak hours. The model should be that for those loads where "time doesn't matter" we (the consumer) can indicate our constraints and then the electricity company will work within those boundaries. Of course, the more lenient the consumer is, the better rate he gets.
Actually, it's quite the opposite. As a time of day electricity user, my utility sends me a forecast of power costs for the next day broken up by hour, and I can plan my energy use accordingly. So, in the future, you'll be able to tell devices in your home above what cost threshold they shouldn't run (with the devices fetching the current and predicted cost of power via a web service). So you work around the energy company and their constraints based on the market price of power in your area.
Here is the graph from my provider:
https://il.thewattspot.com/login.do?method=showChart
To put that another way, a 100m rise with a reservoir that's 50m by 50m by 10m stores 5 MWh, enough to run 200,000 houses for an entire day
Is this supposed to be problematic?.
Yes, very.
5MWh for 200,000 houses is 25 Watt-hours each, or a continuous load of about 1 Watt for a day. That would be about enough for one torch [flashlight] bulb. Are these hen-houses?
Looking at the actuals vs. the predicted costs in the graph you linked, they underestimated by 30%. Maybe they were just having a bad day.
Yep, with those sort of ranges, there's not much use for electric cars. I live in a city center so for about half my car use, those might be okay. However, the other half (pre time I use a car, not milage) when I can't just walk or take the public transit, I'm heading a minimum of 50 miles away and usually more like 100+. The only car that might be useful would be the Tesla with full options. The rest effectively aren't useful enough for me to deal without some sort of gas driven car. No hiking, camping, seeing friends and family in nearby cities. If I still lived in the suburb of a midwestern city, it was not uncommon to drive 100+ miles in one night. Drive into town and shop at a store, go to a friends, go to a night club, drive home. When I was in Houston, just getting in my car to go anywhere seemed like a two hour round trip on the highway. Since in the midwest, one has to drive to anything and it's usually a significant ways away, they really don't look useful for anything.
This raises the question, what does one do when your electric car runs out of juice? You can't really just pick up the battery and carry it to a station to recharge to get enough charge to get to that station with the car. Can a tow truck come charge you up enough to do so? Or do you have to get towed. Given the way my laptop batteries are with inaccurate readings or just cutting out when they get old, I really worry about electric cars.