Will buying an electric car make an environmental difference?

Apr 11, 2011 By Paul Rogers

Sure, you might get a carpool sticker and a tax break. But if you buy an electric car, will it make much environmental difference?

Experts say that depends on three factors: What were you driving before? How is your electricity generated? And how many other electric cars are going to be sold?

In many cases, people who trade gasoline-powered cars for electric ones won't be dramatically lessening the smog they emit. But when it comes to global warming, even when emissions from generating the electricity are taken into account, have a much smaller carbon footprint than gas-powered vehicles because they are much more efficient. However, it will take a decade or more until enough electric vehicles are on the road to make a significant impact.

"If you have a person who is driving a nice, newer car, having them switch to an electric car, there isn't going to be much benefit in reducing ," said Tom Cahill, a professor emeritus of physics at University of California Davis. "But there could be a whole lot of gain in ."

Because all-electric vehicles like the Nissan Leaf burn no , and plug-in hybrids like the Chevy Volt burn only small amounts of gasoline, tailpipe emissions from electric cars are basically zero. In smoggy cities like Los Angeles, driving one on summer days may actually clean the air because the tailpipe emissions contain less pollution than the air.

Yet most people currently buying electric cars weren't driving old, smog-belching vehicles. They are often affluent motorists who drove newer-model gasoline cars. In California, because it has for 50 years had the toughest tailpipe standards in the nation, a 2010 gasoline-burning car puts out only 2 percent or less of the pollution spewed by a 1980s model.

Along with the national-security benefits of reducing America's use of foreign oil, the main societal benefit of electric cars might be their dramatically smaller global warming footprint.

A 2008 study by researchers at Carnegie Mellon University found that life-cycle greenhouse gas emissions, which include emissions from both manufacturing and operating a vehicle, are 32 percent less from plug-in hybrids than from gasoline-powered cars.

That finding was based on America's electricity mix: 45 percent of U.S. electricity is generated from coal, 23 percent from natural gas, 20 percent from nuclear, and 12 percent from dams, solar, wind and other sources.

The global warming footprint of electric cars varies by region. Some states get nearly all their electricity from coal, the most polluting fuel.

Using a nearly all-coal scenario for electricity, plug-in hybrids emit fewer greenhouse gases than gasoline-powered cars, the study found, but aren't as "clean" as ordinary hybrids like the Prius.

"The types of power plants installed in the next two decades will not only affect how much we can reduce emissions from electricity, but also from vehicles," said Carnegie Mellon engineer Kyle Meisterling, one of the study's authors.

In states with cleaner power mixes, plug-in hybrids have less than half the greenhouse gas footprint of conventional gasoline vehicles. Why? Efficiency, said Mark Jacobsen, a professor of civil and environmental engineering at Stanford University.

In cars with internal combustion engines, only 20 percent of the energy goes to move the car and 80 percent is wasted heat, he said. But in an electric car, 80 percent moves the vehicle and only 20 percent is wasted.

"Electricity is more efficient," Jacobsen said. "As a result, you just need less energy."

In a recent study, Jacobsen computed the carbon footprint of every major energy source, wondering which would be greenest if America converted all its vehicles to run on each. He found that electric vehicles powered by wind energy were best, with a 99 percent reduction in carbon and air pollution emissions from the current vehicle fleet. In fact, every vehicle in America could run on the electricity provided by 144,000 5-megawatt wind turbines, he concluded.

Building them sounds like a massive job, but he noted that the United States built 300,000 airplanes during World War II. Ethanol ranked last in his study, with the largest .

"There's no technical reason we can't ramp up to a lot more electric vehicles," he said. "It's a question of whether society as a whole is motivated to do it."

Gas prices at $5 a gallon might provide motivation. But even then, the transition is expected to be slow. Americans bought 11.6 million vehicles last year. Including the popular Prius, just 2.4 percent were hybrids. Only three automakers - GM, Nissan and French firm PSA - plan to produce more than 10,000 a year by the end of 2011.

"Almost anything you do won't have much effect for five to 10 years because you have all these used cars that stay on the road for so long," said Tom Turrentine, director of the Plug-in Hybrid Electric Vehicle Research Center at UC Davis. "It takes 10 years to really move through the fleet and change it. But you've gotta start somewhere."

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User comments : 14

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Doug_Huffman
1 / 5 (1) Apr 11, 2011
He found that electric vehicles powered by wind energy were best,...
Ready about? Jibe ho!

NIMBY is the only difference.
Skeptic_Heretic
not rated yet Apr 11, 2011
To respond to the article title, depends on the electric car and the infrastructure that goes along with it.
wolfkeeper
5 / 5 (1) Apr 11, 2011
The thing is, in some places like the UK, you can pick your electricity supplier, and so you can then guarantee that your vehicle is clean.

Doing it that way would mean that you're putting money into clean energy, and doing that will tend to get more windmills built.
Vendicar_Decarian
1 / 5 (2) Apr 11, 2011
There is no need for any of this according to American TeaPublicans, who insist that all natural resources on earth are effectively infinite.
ryggesogn2
1.4 / 5 (9) Apr 11, 2011
"There's no technical reason we can't ramp up to a lot more electric vehicles," he said. "It's a question of whether society as a whole is motivated to do it."

That's why the environuts keep up the scare tactics and want to create a war-time environment to force their vision of utopia.

The best and most reliable indicator of scarcity is price. The real, market price, not one subsidized by any govts.
The Soviets eventually understood this. Too bad the rest of the socialists don't get it.
Quantum_Conundrum
4.3 / 5 (6) Apr 11, 2011
ryggesogn2:

You're an idiot.

Solar power costs a lot up front, but long term it is the cheapest thing there is, by far.

Check my post on that article about Google investing in a new solar power plant.

At present energy costs, that thing is going to provide a return on investment of well over 4 billion dollars across the next 25 years.

These companies will eventually be able to provide power for HALF existing long term costs of coal or nuclear, and will still make a 500% profit or more over 25 years, which makes most stocks and bonds look like garbage...
Skeptic_Heretic
5 / 5 (5) Apr 11, 2011
That's why the environuts keep up the scare tactics and want to create a war-time environment to force their vision of utopia.
Are you saying Bush junior is an environut or are you saying scientists invaded Iraq and Afghanistan?
Jimee
not rated yet Apr 11, 2011
I feel there isn't enough emphasis on being a leader toward a(n eventually) much less harmful technology. Leading the way to a less poisonous and healthier world seems like an important and practical goal.
ryggesogn2
1 / 5 (4) Apr 11, 2011
At present energy costs, that thing is going to provide a return on investment of well over 4 billion dollars across the next 25 years.

Is that why the govt has to subsidize the industry?
unknownorgin
3 / 5 (2) Apr 12, 2011
How do you define environmental? The electric car will have so many metals in it that are now considered toxic because of the electronics needed that the 10,000 plus wreaked cars a year will have to be shipped off shore to be recycled. what about the 100,000 tons a year of bad batterys and feul cells?
All that plastic in the interior and body will end up being burned in a power plant. Environmental overegulation and the fact that nothing is built to last more than 5 years have condemed the electric car to only be a toy for the very rich.
Eikka
not rated yet Apr 12, 2011
The thing is, in some places like the UK, you can pick your electricity supplier, and so you can then guarantee that your vehicle is clean.


That is total bunk. The electricity is still coming from the plant nearest to you, and when you turn the charger on, the computer at the power station puts more coal in the fire.

Someone else is going to use your "clean" energy somewhere else, and it just means that both the coal and the wind or whatever power gets used.
wiyosaya
not rated yet Apr 12, 2011
The thing is, in some places like the UK, you can pick your electricity supplier, and so you can then guarantee that your vehicle is clean.


That is total bunk. The electricity is still coming from the plant nearest to you, and when you turn the charger on, the computer at the power station puts more coal in the fire.

Someone else is going to use your "clean" energy somewhere else, and it just means that both the coal and the wind or whatever power gets used.

I have to agree, though I would like to believe otherwise. It is marketing that is aimed at the conscience of the target market. Where I live, we can pay extra to support green energy. I refuse to do so as I believe it represents a profit opportunity for our local electric utility.
wiyosaya
not rated yet Apr 12, 2011
Personally, I think the investment in the technology will foster future developments in areas like batteries, ultra-capacitors, electric motors, and electric generation.

This study really presents nothing that has not already been known for years; mainly, that even with the dirtiest electrical generation technology currently available, electric cars represent significantly cleaner technology. I wonder if they factored in the pollution generated by transporting gasoline to the end-user.

I have my doubts about their hybrid vs PHEV conclusions. With the volt, this is certainly the case; however, you can bet chevy made the volt as cheaply as possible with little regard to long-term efficiency. 28mpg after battery drains is not at all impressive. My gen 2 US Prius gets twice that.

I am extremely happy that this study points out ethanol for what it is - the worst polluter by far. Now if only those who make decisions would listen to this study instead of the corn lobby.
kaasinees
1 / 5 (2) Apr 12, 2011
How do you define environmental? The electric car will have so many metals in it that are now considered toxic because of the electronics needed that the 10,000 plus wreaked cars a year will have to be shipped off shore to be recycled. what about the 100,000 tons a year of bad batterys and feul cells?
All that plastic in the interior and body will end up being burned in a power plant. Environmental overegulation and the fact that nothing is built to last more than 5 years have condemed the electric car to only be a toy for the very rich.


It really depends on the car ... if we compare electric vs fuel and ignore the materials used than it should be more environmental friendly. Yes the batteries are toxic, but they can be made recycable, but so are mining coal and oil, if not way more toxic. The materials used in the car is really a non-argument, new fuel cars are starting to use more aluminium which also produces toxic by products.

In the end the debate is useless.