Dearest Umbra,
Why are electric cars considered so great? They don't pollute the air where they are driven. But certainly when they are plugged in they use energy from a power plant, which does pollute and also contributes to global warming. Doesn't this just move the pollution from one area to another? Then you have to consider that there are power losses when electric energy travels over transmission lines. Are electric cars more efficient -- using less energy per mile? What gives here?
Patricia Rice
Lafayette, Colo.
Dearest Patricia,
Many people think electric cars are the bee's knees. They do have tangible benefits and a lot of potential, but also a few drawbacks.
Before cheap oil, electric cars were
common.
Photo: Courtesy National Museum of
American History
The benefits include a totally silent engine, and -- depending on gas and electricity prices -- a cheaper ride than a comparable car powered by gas or diesel. Also, as you suspected, electric cars are much more efficient than gas-powered ones. This has to do with engine design. For an example, let's look at the new "it" car for greens with means: the 250-mile-range, 0-to-60-in-four-seconds Tesla Roadster. An Australian newspaper raves, "Unlike a traditional V8 engine, with its eight pistons, eight connecting rods, crankshaft, valves, oil pumps, and other mechanicals, the Tesla's engine has only one moving part. This gives it an efficiency rating of about 95 percent, compared with the 20 percent (or less) of an internal combustion engine." I doubt you or I will be snapping up a Tesla anytime soon, but it's still nice to think about a pleasant, simple engine like that.
But even though the engines are more efficient, that doesn't mean electric cars are more efficient overall. When you consider the fuel source, the calculations get tricky, because the source of electricity for an electric car can vary quite a bit. In a paper Tesla Motors published [PDF] recently, the company calculates that when the source of electricity is an efficient combined-cycle natural-gas generator, the fuel efficiency of the Roadster, even taking into account the power lost during transmission, is nearly twice that of the Prius. When the actual average energy mix of the U.S. grid was considered, the Roadster still beat all the other gasoline and diesel vehicles (even hybrids), though not by nearly as much. As far as pollution goes, check out this handy lifecycle assessment (hooray) to get a better sense of how different types of power sources affect the CO2 produced by different types of cars.
Your concern about pollution and global warming is justified. I think the real hope is that someday our power sources won't be so dirty, which will make electric cars a near-perfect way to get around. While much of the power in the U.S. and the rest of the world currently comes from coal, nuclear, and natural gas, it's at least possible to run your electric car on clean, renewable energy. Check your region's source if you don't know where your power comes from, and look into the option of buying green energy from your utility. It costs a little more right now, but it's worth it.
Right now, the electric car might not be The Answer, despite what rabid fans say. Besides the likelihood of fueling with dirty power, some of the current models have a relatively limited range -- depends on the length of the cord. But as the Tesla people show, there are brains out there working on improving this scheme. Someday we will all be zooming silently around. (You know I was kidding about the cord length, right?)
Juicily,
Umbra
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Comments
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cgarlow Posted 6:16 am
23 Aug 2006
Most new usage by electric vehicle owners, and there aren't many now, nor will there be unless and until we get Big Auto to hop to it, will be generated by renewable energy. Most EV owners are people like me who want to save the earth and so we buy our electricity from solar and wind, as anyone can. http://www.newwindenergy.com, http://www.greenpower.gov and others. Even if there are some who buy whatever is available, the average electricity "gallon" is alot cleaner than gasoline gallons, and the electricity costs are 75 cents per gallon versus $3 plus for gasoline.
And electricity is getting cleaner all the time as we are suing and forcing coal plants to clean up their emissions, and some states are forcing reductions in CO2 from coal plants, like my state,Maryland.
What about Umbra's Institute of whatever it was lifetime CO2 emissions article? It shows that even with 100% coal [which no one has] as the fuel source, EVs emit less CO2 than gasoline and with cleaner electricity EVs are miles ahead in the race to stop global warming.
EVs and plug in hybrid cars powered by solar and wind are the way to stop global warming. Current proposals to put solar in an internal combustion engine, like ethanol, are getting nowhere fast and are left in the dust by my EV.
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aloneindc Posted 7:16 am
23 Aug 2006
Karen
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Bensch Posted 9:57 am
23 Aug 2006
The range limitations then were about the same as they are today - battery technology really hasn't come that far, and it can't! It's more limited by physics than design, just like the amount of energy necessary to create a given number of lumens has been the same for fluorescent light technology ever since Tesla came up with it in the first place.
We expect the car, a single solution, to meet all of our needs. This is ridiculously inefficient - cars are bad for short trips, and also bad for very long ones. But we expect the car to take us 100-200 miles regularly, when those trips would be more efficiently made by rail in any other first world country.
This will change - in Washington, for instance, we're slowly ramping up our Amtrak Cascades service, now primarily funded by the state, rather than federal, government. California's High Speed Rail Authority has completed an environmental impact statement as well as other necessary documents to move forward with 220mph electric rail service similar to the Japanese Shinkansen, French TGV or German ICE. That service will be time and cost competitive with air travel.
With public support for new highways eroding and our existing systems largely at capacity, longer distance transit systems are beginning to see a new renaissance. With them comes a shift in expectations for private passenger vehicles, and a shift in our land use back toward more compact communities.
The real issues for electric vehicles do come in the form of electrical generation. With California's new solar mandate, wind farm construction at an all time high, and more efficient appliances and lights coming to many consumers, you'd expect to see a surplus of power - but these are being met by forced closure of coal and oil-fired plants as well as the potential demolition of hydroelectric dams on major fish runs. With the concept of peak oil also translating to our uranium supplies, I don't think we're going to be able to generate the kind of power necessary for everyone to drag 3,000 pounds of steel on inefficient rubber tires - especially when our communities adapt to lend themselves to walking and bicycling.
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Bensch Posted 9:57 am
23 Aug 2006
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Tod Brilliant Posted 12:35 pm
23 Aug 2006
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Biodiversivist Posted 12:46 pm
23 Aug 2006
You still end up with something like the EV1, a short range, very heavy vehicle that costs an arm and a leg that takes all night to recharge. There is a guy here in Seattle who converts cars and he's booked up. It might be worth waiting for a plug-in from Toyota.
Well done Umbra.
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scatter Posted 6:53 pm
23 Aug 2006
Once the mass market takes off, legislation may be necessary to ensure EVs don't displace emissions from the tailpipe to the power station stack. Until that point, most EV purhcasers are likely to be environmentally conscious.
I'm surprised you didn't mention the battery though. These are full of all sorts of environmental nasties however the good news is that these are recyclable and in Europe this is now a legal obligation.
EVs are definitely The Answer for personal transport (once they sort out some battery recharge and range issues).
Forget combustion engines - as you said they are grossly inefficient.
Forget fuel cells - it's a costly distraction that is wasting time: Why take electricity (from wind or solar), use it to split water into hydrogen and oxygen, transport it to your car, fill up a tank, and then recombine the hydrogen with oxygen to generate electricity again in a fuel cell to power an electric motor?
EVs cut out the middle man and just imagine where we'd be now if the car manufacturers had invested all those billions in proven battery technology?
And indeed yay for life cycle analyses! We need much more of this, ESPECIALLY when it comes to products that claim to be sustainable. Proper LCA is the only way we can work out what is the best option - I can't emphasise this enough!
http://www.ilea.org/ is worth looking at, although is now sadly defunct.
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Bensch Posted 3:08 am
24 Aug 2006
I'd love to know where we're going to get all this electricity, though.
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sunflower Posted 3:29 am
24 Aug 2006
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scatter Posted 7:14 pm
24 Aug 2006
More conventional cars will have cheaper and smaller packs and both cost and size will rapidly come down as technology improves but it's still not an easy task.
Much better will be fast recharging battery technology like what Toshiba is developing (http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm) although you'll need a special charger to be able to pump electricity that quickly.
As for where the electricity will come from, if EVs take off then the demand for renewable energy will explode and massive construction of wind and solar plants will follow with a consequent reduction in green electricity costs. Maybe EVs will prove to be the tipping point for renewables? We shall see...
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KayLansky Posted 5:05 am
29 Aug 2006
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hewman1 Posted 9:54 am
04 Nov 2006
I'm not!
Someone else called the GM EV1 heavy and slow-to-charge. I drove an original, lead acid-battery EV1 and beat everything out of stoplights with it. The weight of even old-tech lead cells is nearly offset by the absence of a heavy internal-combustion engine (plus all its complicated support systems,) transmission and fuel tank.
Also, advanced batteries now weigh a quarter as much, making electric vehicles ligter than equivalent gas cars.
Another point: the original 1996 EV1 recharged (in free public charging spaces) to 80% full in two hours while I shopped or ate a leisurely lunch. The full six-to-eight hour charging took place at night while I slept. GM built an improved model EV1 with quicker-charging nickel-metal hydride batteries in 1998.
Another person thought that GM sold EVs. Of several thousand of eight EV models built by six major automakers for US use, only a few hundred of two models (Ford Ranger EV and Toyota RAV4 EV) were ever offered for sale, at double the price of their gas equivalents. They were snapped up. All the other EV models were closed-end leased and have nearly all been repossessed and crushed. This (as well as the lack of marketing and lawsuits to avoid EV requirements,) is definitely not normal automotive business practice.
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