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."

Comments

Well.. being in that biz

[gearloos]

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..

Re:Well.. being in that biz

[Rei]

Your correct but the environmentalist want every car on the road to be either electric or hybrid, preferably electric. Hmm about 25,000,000 cars registered in CA give or take, so at a 2kwh charging load thats 2,000 & 25,000,000 = 50,000,000,000 or 50 gigawatt hours and that is more then the entire supply that the state of California has available and thats a combination of all available fuels we have on line.

Yeah! And my gasoline car burns about two gallons per hour of driving. Hmm about 25,000,000 cars registered in CA give or take, so 2 gallons per hour times 24 hours * 365.24 = 440 billion gallons of gasoline per year, three times what the whole US consumes!

(I.e., the problem with your calculation is that people's cars don't charge nonstop; they charge intermittently and in a staggered manner, whenever people or a smart grid tells them to. Never will they all be charging at the same time)

The next problem is that gigawatt hours are a measure of energy while 2 kilowatts (not kwh) is a unit of power.

That is the myth if the electric car, if we shift to all electric we simply shift the fuel consumption to another type of engine.

That's the "long tailpipe myth", and it's a myth. All peer-reviewed studies on the subject show that it's much better to switch to electric.

Now an electrical generating plant is more efficient then an internal combustion engine but you have to build out that capacity and keep a lot of it on hot stand-by because it takes a long time to spin up from cold to generating electricity

Wrong; utilities love EVs because the stabilize and even-out the load, meaning *less* need for peaking and spinning reserve.

Additionally no one is really talking about the insanely toxic batteries that will have to be disposed of on a regular basis.

You clearly have no clue what you're talking about. You can literally, legally throw discharged A123 batteries into municipal trash. The CEO of BYD likes to show off by *drinking* his batteries' electrolyte. As for "regular basis", we're talking ~80% capacity in 10 years.

Technology can move fast but we are pushing the limits of known technology as far as electrical storage is concerned

Not even *close*. I could list about a dozen cathode techs and two dozen anode techs, each of which could increase the density of their respective electrode ~50% to ~1000%. Will all of them make it to commercialization? Not a chance. Will *none* of them make it to commercialization? Likewise, not a chance. The rate of battery energy density increase has been a pretty steady 8% per year, but it's actually *increasing* of late.

There is a lot of progress being made in Electric double-layer capacitor "EDLC's" but even those are still experimental and cannot provide the kind of power you would need to run say a Tesla car

That's backwards. Capacitors have huge power density but poor energy density.

No problem, long as they charge at night

[Geoffrey.landis]

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.

Re:No problem, long as they charge at night

[TooMuchToDo]

Is there a dummy load set up somewhere?

Sort of. What happens is the power company almost gives away the power between midnight and 5am to industrial customers and large cities with *lots* of street lights. Nuclear power plants in particular run extremely poorly at anything under 90% of what they're rated to run at, whereas natural gas generators, hydro, etc can be scaled forward and back.

Re:No problem, long as they charge at night

[digitalunity]

Not sure if you know why, but the European Union passed a Restriction on Hazardous Substances law which limits among other things lead in all products sold in the EU. Sadly. the market in the EU is so large that many manufacturers simply changed over all their production lines to use lead-free solder and other products.

What I've heard that with lead-free solder is that it will eventually grow hair like structures between wave soldered IC pins that are closely spaced and they aren't protected with conformal coatings. This causes malfunctions in equipment. Lead prevented that from happening but it was decided, for whatever reason, that being lead-free was better for the environment than the waste the changeover created.

Re:No problem, long as they charge at night

[afidel]

They also often have to scale down during the hottest times of the year due to problems with thermal pollution of their heat sinks (rivers or lakes).

Re:No problem, long as they charge at night

[Rei]

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?

Want to see a TON of storage? Run the numbers on pumping a couple meters of water back and forth between Lake Superior and Lakes Michigan/Huron. ;)

Re:No problem, long as they charge at night

[Rei]

And the latest NG plants are now up to 60%, NOT counting that you can reuse the waste heat for industrial heating. 60% just for the electricity generation.

The grid is ~93% efficient, chargers ~92-93% efficient, li-ions 94% (inefficient rapid charging) to over 99% (efficient slow charging) in efficiency, and the drivetrain averages 85-90% efficiency in normal usage.

Non-hybrid gasoline ICEs average about 20% efficiency since the engine runs out of its optimal operating envelope most of the time and much energy is wasted through braking. Diesels average about 25% (their mileage numbers look even better, but part of that is due to the greater density of diesel fuel). Gasoline hybrids can get 30-35% efficiency (diesel hybrids even more, but the added weight and complexity is rarely considered justified by manufacturers).

Re:No problem, long as they charge at night

[QuantumPion]

Sometimes you end up having to scale your nuclear plant back because there's so much renewable energy:

http://green.blogs.nytimes.com/2010/07/07/sudden-surplus-calls-for-quick-thinking/

Columbia is accustomed to reducing power to 85 percent and sometimes 60 percent. In the following days, however, BPA asked the nuclear [note: I added "nuclear" for context] plant operators to go down to just 22 percent. “This year was extraordinary because it all came so heavy and so fast,’’ Mr. Milstein said.

Here by renewable energy, you mean hydroelectricity. And they had an excess due to larger than normal amount of rain. And the reason why they had an excess of electricity was because they lacked the transmission capacity to sell the power to other areas where it was needed.

Re:Is this future tense?

[copponex]

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

Vehicle to Grid

[onthegrid]

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?

Re:What if...

[rsborg]

You were being funny, but I think it's important to point out: we produce about 14 exajoules of energy for electric power a year. We use about 28 exajoules for transportation.

This study seemed to overlook something rather important.

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.

Re:Plus they could be set to charge at night

[cgenman]

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