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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."
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"
This IEEE article (http://spectrum.ieee.org/green-tech/advanced-cars/speed-bumps-ahead-for-electricvehicle-charging) states a Level 2 EV charger can draw as much as 6.6 kilowatts.
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
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
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?
A constant mid-high usage is basically the best case scenario for a power grid. This is especially true where nuclear power plants and other electricity producers can't actually be scaled back during low-load situations.
The ______ Agenda
No, I think the study's numbers are on-base. Electric car adoption will not be 100% overnight (or we'd be pretty screwed). They are assuming 500K (out of 300M) cars with current power plant base loads... and that would be 0.0017, about 1/6 of one percent. I think our nighttime base load (which throws away energy right now) can handle it.
And that's assuming you are calculating actual energy converted from gasoline (a horrible conversion loss) and you are not conflating industrial/commercial transport with personal transport.
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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
And then the fact that you have to replace a major and expensive component of your vehicle (batteries) every 3-5 years.
Where are you pulling that figure from?
I doubt the battery lifespan is going to be that short when the Chevy Volt (for example) is coming with a 150,000 miles/10 year warranty, and Nissan seems likely to follow suite with the Leaf.
upon the advice of my lawyer, i have no sig at this time
The biggest heat sources in an electric vehicle are the inverter and the motor. Li-ion pack efficiencies vary a lot depending on the particular chemistry choice and operating conditions. I've seen as low as 94% and well over 99% (some chemistries really are absurdly efficient). There's also some losses in the cabling.
Chargers are not "80-90%" efficient. They're usually 92-93% efficient.
Trump's plan to get rid of Mueller appears to be 'be so guilty of so many things that Mueller works himself to death.'
As usual, the answer is "it depends", with lots of assumptions you can argue about in the absence of actual data.
A biggie is where the grid electricity comes from.
Another is how long the batteries will last, and how long an electric car will last. There have been studies claiming that a Hummer has lower life cycle emissions than an electric car, but they assume an absurdly long lifetime for Hummer and an absurdly short lifetime (and no recycling) for the EV.
Google "life cycle emissions BEV" or something like it and you'll have many hours of reading material on the matter.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
I don't think he needs to look up "spinning reserve", he has (almost) described it.
Nuclear and the most efficient other power stations provide the base load. Other stations provide spinning reserve where their alternators are syncronised to the grid, turning at grid frequency but with little or no power input. The boilers of spinning reserve fossil fired stations are kept hot but with little energy flow. There is not much wasted energy - despite some crazy theories here about dumping electricity to resistor banks and even light bulbs, ffs!!!! Spinning reserve stations can be brought on-line in minutes.
Other stations are shut down but at standby, with levels of notice required to join the grid typically hours (but days for a nuclear). Hydro stations however can start and stop generating like at the turn of a tap.
The GP's last paragraph was perfectly logical. Currently electricity is sold cheap at night (to local distributors, factories, railways and some end consumers) because of the otherwise wasted capital and attendance costs of the spinning reserve, not because much fuel is being wasted. However if there were greater demand for night electricity, the price of night electricty (and I believe the GP meant night electricity) would go up with market forces.
Like the grocer might sell stale bread cheaper than fresh. But if there were suddenly a big demand for stale bread, because someone had invented a gadget to restore it, he would put its price up (even if not as much as fresh bread) believe me.
I am a (nuclear) power station engineer btw.
... I bought one of these, and based on watching my loads over time, 2 kilowatts is no big deal at all. My dryer uses way more power than that. In fact, an electric toaster uses over a kilowatt. So not only could you charge an electric SUV, you could charge an electric freaking train and still have enough capacity to spare.
...and the situation seemed more worrisome than this article suggests. I assumed that, eventually, people will shift to all-electric vehicles as opposed to hybrids. Below are the numbers I used. Did I flub the math? Because these calculations sure seem to suggest an electricity crunch as we move off petroleum:
Total miles driven in the U.S. yearly: 3x10^12 mi
http://www.greencarcongress.com/2008/05/us-vehicle-mile.html
Electricity use per mile for a fully electric car: 0.17 to 0.37 kWh/mi (mean: 0.27)
http://en.wikipedia.org/wiki/Electric_car#Energy_efficiency
Total electricity needed to support all miles driven by fully-electric vehicles: 3x10^12 mi * 0.27 kWh/mi = 8.1x10^11 kWh
Total yearly electricity production of the U.S. (2007): 4.157x10^9 kWh
http://en.wikipedia.org/wiki/Electricity_sector_of_the_United_States#Electricity_generation
In other words, if we assume that hybrid/electric vehicles currently account for an insignificant portion of total miles driven, and we were to covert all vehicles to be fully electric, U.S. electricity production would have to increase by a factor of 194 in order to support the additional load.