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Power Transportation

Electric Car Environmental Impact: Power Source Matters 341

another random user writes with news of a study from the Norwegian University of Science and Technology, which looked into the environmental impact of electric vehicles — not just how they do when driven, but how they are produced and by what means they are charged. The study pointed out that the production of EVs has twice as much of an environmental impact as the production of typical gas-powered cars, which must be taken into account when comparing the two. Also, they say it's important to consider the source of the electricity used to charge the vehicles. In places like Europe, where a good chunk of the electricity comes from renewable sources, EVs do indeed provide a benefit to the environment. However, "In regions where fossil fuels are the main sources of power, electric cars offer no benefits and may even cause more harm." The study says, "It is counterproductive to promote electric vehicles in regions where electricity is primarily produced from lignite, coal or even heavy oil combustion."
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Electric Car Environmental Impact: Power Source Matters

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  • Re:Captain Obvious (Score:5, Informative)

    by pixelpusher220 ( 529617 ) on Friday October 05, 2012 @10:53AM (#41558721)
    'bonehead' - great name, you do it proud.

    "Pure electric? Zero chance." Uh, electric doesn't mean battery powered it means it runs on electricity. The Chevy Volt is completely electric under 60 mph. Even when the battery runs out, it's still 'electric' via the gas generator. It runs on electricity. How it gets that electricity is up to you. You could put a 2nd battery pack in, or use hydrogen fuel cell, or propane as you suggest. Whatever, the important part is getting to electric propulsion so now your fuel can come from anything rather than 'only' a limited and polluting fossil fuel source.

    Diesel-Electric locomotives are 'electric'. They get their electricity from diesel generators, but the motors are still 100% electric. Why? Because it's more efficient. The Volt is basically the same thing.

    What needs to still improve is the technology for storing energy. Today the single best energy storage mechanism is fossil fuels. Unfortunately there are some significant draw backs to using this as a fuel source.
  • Re:Captain Obvious (Score:5, Informative)

    by itof500 ( 239202 ) on Friday October 05, 2012 @10:57AM (#41558751)

    Do the math;
    With regard to climate change/CO2 production it matters a great deal where the energy comes from.

    Here in central Indiana our electricity comes from coal fired power plants down on the Ohio river. Each kW-h of electricity produces 1.88 libs of CO2 (ref Duke Energy mailings). The EPA rates the Nissan Leaf as using 34 kW-h to go 100 miles (ref []). So, doing the math going 100 miles through the Indiana countryside in the Nissan Leaf produces about 64 pounds of CO2.

    How does that compare to burning gasoline? Burning that gallon of gas produces 20 lbs of CO2 (ref []), so the 64 lbs of CO2 for the electricity to drive the LEAF 100 miles is equivalent to 3.2 gallons of gasoline. That figures out to 31 miles per gallon.

    Nissan LEAF -> 31 miles per gallon.


  • Re:Captain Obvious (Score:5, Informative)

    by Hillgiant ( 916436 ) on Friday October 05, 2012 @11:19AM (#41558997)

    30% of the energy in the fuels gets used for moving

    Oh, it's worse than that. At steady state, the very best that a perfect engine (frictionless bearings, dragless intake, massless pistions, etc) can achieve is around 35% [] at steady state. Add real-world parasitic losses and acceleration and I'm pretty sure the efficiency drops into the teens.

    I will grant that calculating losses between the power plant and the car battery is difficult, but your average combined cycle power plant is starting off at 60% Carnot efficiency, has proportionally lower parasitic losses, and can be much more cost efficient in pollution controls. I.e. it is more difficult to reduce one ton of carbon emissions at each of 100 tailpipes than 100 tons at one stack.

  • Re:Variables (Score:5, Informative)

    by bonehead ( 6382 ) on Friday October 05, 2012 @11:49AM (#41559431)

    The advantage of the small diesel is that it can provide charging at all speeds including idle speed.

    Actually, the big advantage of decoupling the IC engine from the drivetrain is that when the IC must be used, it can run at its ideal RPM range at all times, independent of vehicle speed. That means that 10 gallons of diesel burned in a hybrid vehicle will produce less pollution than the same 10 gallons burned in a conventional diesel vehicle.

  • by Medievalist ( 16032 ) on Friday October 05, 2012 @11:51AM (#41559449)

    I was under the impression that the manufacturing processes to make the power plant / batteries for *POPULAR BRAND OF HYBRID VEHICLE* released the equivalent quantity of CO2 into the atmosphere as would be saved by the reduced CO2 released by the hybrid drive over it's serviceable life.

    That's neo-con disinformation, operating at several levels, that is being distributed by marketing organizations like CNW. Not only is it factually incorrect, it also implies CO2 is the most significant car exhaust pollution issue, which it certainly isn't, and ignores the fact that auto batteries are recycled (in the USA) at a rate exceeding 95%.

    There's also the issue of "service life". We all heard the stories of how buying a new Prius battery would cost more than the car, and we'd have to do it every three years - yet I have 130,000+ miles on my ten year old battery pack and it has had zero maintenance and zero problems. Other people have gone 300,000 miles with no issues. Good quality electric motors, such as the traction motors in Japanese hybrids, have a 40 year service life before rebuilding - and if the bearings are replaced at the first sign of heat or noise brushless motors can last over a hundred years. I have an 80 year old electric fan in my house (it has hand-wound coils and hand-cut steel gears in the oscillating mechanism) and it works better than modern plastic chinese-made fans - pushes more air and uses less energy, because it's extremely well made. Service life estimates based on worst-case fantasies of hybrid haters are clearly not realistic.

    The net being a loss to society, as the process for making the batteries released toxic elements not used in making regular combustion engine cars.

    Again, this is factually incorrect. Even if you accept the ridiculous definitions of pollution and service life, it's still just plain not true, and has been repeatedly [] debunked [] in peer-reviewed [] literature [] and in journals []. Of course the Wall Street Journal and Fox News will keep repeating absurd anti-environment propaganda forever, but those are not reality-based [] news sources.

  • Re:Captain Obvious (Score:5, Informative)

    by Grishnakh ( 216268 ) on Friday October 05, 2012 @11:52AM (#41559477)

    No, not always, but it really depends. A lot of industrial processes become more environmentally-friendly over time. As an example, making lead-acid batteries probably used to be a lot worse than it is now, as all that lead had to be mined somewhere. These days, you don't really need to mine for lead any more, since lead-acid batteries are recycled with extreme success (nearly 100% of the lead in batteries is recycled), thanks to aggressive recycling programs with car batteries (every time you buy a new battery, they take back your old one and send it off to be recycled). So if lithium mining is a problem with new EV Li-ion batteries, for instance, that probably won't be so much of a problem farther into the future as the material is recycled more.

  • Re:Captain Obvious (Score:5, Informative)

    by martyros ( 588782 ) on Friday October 05, 2012 @12:28PM (#41559907)

    Nissan LEAF -> 31 miles per gallon.

    So, about equivalent to a light gasoline car, except:

    • it doesn't create any smog in a city
    • it's ready with 0 cost, modification, or anything to switch from fossil fuel to nuclear or renewables.
  • Re:Captain Obvious (Score:4, Informative)

    by Greenspark ( 2652053 ) on Friday October 05, 2012 @01:23PM (#41560563)
    How about, like toll roads? They justified those birds with the promise that 'one day they would be paid for' -- i think we all know by now that it's never gonna happen.

Never worry about theory as long as the machinery does what it's supposed to do. -- R. A. Heinlein