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Electric Cars Are Cleaner Today and Will Only Get Cleaner Tomorrow

Max Baumhefner

Posted August 5, 2013 in Curbing Pollution, Moving Beyond Oil, The Media and the Environment

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By Max Baumhefner and Cecilia Springer*

Uncovering a fraud is uniquely satisfying, which is perhaps why news outlets continue to provide electric car deniers with a platform to proclaim they aren’t as green as they appear. But close examination reveals the latest round of skeptics to be lacking in substance. Numerous peer-reviewed articles have reached the same conclusion — from cradle to grave, electric cars are the cleanest vehicles on the road today. And unlike cars that rely on oil, the production of which is only getting dirtier over time, the environmental benefits of electric cars will continue to improve as old coal plants are replaced with cleaner sources and manufacturing becomes more efficient as it scales up to meet growing consumer demand.

“Did you account for the pollution from the electricity it takes to power the vehicles?”

This question has been asked and answered. Using today’s average American electricity mix of natural gas, coal, nuclear, hydro, wind, geothermal, and solar, an electric car emits half the amount of harmful carbon pollution per mile as the average new vehicle. In states with cleaner mixes, such as California, it’s only a quarter as much. To find out how clean your electric car would be today, plug your zip code into the EPA’s “Beyond Tailpipe Emissions Calculator.” Those benefits will only improve as the electric grid becomes cleaner over time.

Before NRDC began advocating for vehicle electrification, we did our own homework, publishing a two-volume report in partnership with the Electric Power Research Institute. The work took almost two years and concluded that a long-term shift to the use of electricity as a transportation fuel provides substantial reductions in carbon pollution and air quality benefits.

It’s essential to take a long view when examining vehicle electrification because the electric grid doesn’t stand still. Since the time we published that report, the EPA has adopted power plant standards for mercury and other air toxics, ozone-forming emissions, fine particulate pollution, soot and coal ash, proposed standards for greenhouse gases from new power plants, and has been directed by the president to adopt greenhouse gas standards for existing plants. Meanwhile, twenty-nine states have adopted renewable energy targets to reduce emissions. Driving on renewable electricity is virtually emissions-free.

“Did you account for the resources it takes to build the cars?”

Producing an electric car today requires more resources than producing a conventional vehicle, generally due to the large batteries. However, comparing the efficiency of relatively nascent and small scale electric vehicle manufacturing to the efficiency of conventional automobile production, which has benefited from more than a century of learning-by-doing, is misleading. Automakers are racing to save money and materials through recycling and more efficient production. Those who win the race will win the market.

Even with today’s technology, on a lifecycle basis, the electric car is still the cleanest option available. Higher emissions from manufacturing are more than offset by the substantial benefits of driving on electricity. We examined six peer-reviewed academic studies and found that in every case, electric vehicles win by a substantial margin, with estimates ranging from 28 to 53 percent lower crade-to-grave emissions than conventional vehicles today.[1] 

Opponents often rely upon the original version of a Norwegian study (Hawkins 2012), which has much higher estimates of emissions associated with the production of electric cars. Those skeptics generally cherry-pick from the original version of that article, and ignore the fact it was corrected post-publication, resulting in its estimate of the comparative emissions benefit rising from 22 percent to 28 percent. In other words, even the source relied upon by skeptics shows a substantial lifecycle advantage for electric cars.  The Norwegian study finds the lowest benefit relative to the other articles examined partially because it includes an estimate of emissions associated with the disposal of advanced battery materials that is higher than other studies, which brings us to the next question:

 “What about mining and disposing of the materials needed to make the batteries?”

First off, there is no shortage of the materials needed to make advanced vehicle batteries. A recent article in the Journal of Industrial Ecology concludes, “even with a rapid and widespread adoption of electric vehicles powered by lithium-ion batteries, lithium resources are sufficient to support demand until at least the end of this century.” Another analysis of the trade constraints associated with the global lithium market came to a similar conclusion, and noted that even a “five-fold increase of lithium price would not impact the price of battery packs.” Furthermore, companies like Simbol Materials are already finding innovative ways to acquire lithium by harvesting materials from the brine of geothermal power plants — no mining required.

Secondly, advanced vehicle batteries are unlikely to be simply thrown away; they’re too valuable. Even once they’re no longer suitable for automotive use, they retain about 80 percent of their capacity and can be re-purposed to provide grid energy storage to facilitate the integration of variable renewable resources, such as wind and solar. Automotive batteries can also be re-purposed to support the electrical grid at the neighborhood level, preventing the need to invest in costly distribution system equipment. Pacific Gas & Electric plans to use money saved through the strategic deployment of used battery packs in neighborhoods throughout Northern and Central California to provide electric car drivers with rebates to reduce the purchase price of new electric cars.

Finally, those batteries that aren’t re-purposed will likely be recycled. Conventional vehicle manufacturing is one of the most efficient industries in the world – around 95 percent of vehicle parts are recycled, reducing the energy needed to make more parts.  It is worth noting that conventional lead-acid car batteries are consistently the most recycled product for which the EPA provides data, with a recycling rate of 96 percent. Advanced battery recycling could cut associated emissions in half, according to a 2012 study from researchers at Argonne National Laboratory.  Companies are already investing in such technologies.

In summary, a sustained and serious examination of the cradle-to-grave impacts of electric cars reveals they are the cleanest option available today, and that the environmental benefits of vehicle electrification will only increase over time. That’s not only good news for the eco-conscious, but for any consumer interested in driving on a cleaner fuel at a price equivalent to buck-a-gallon gasoline. For more, see Real Oil Independence: Buck-a-Gallon Electricity for Life.

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*Cecilia Springer is an associate at Climate Advisers, where she manages projects on transportation and sustainable supply chains.


[1] Ma (2012); EPA (2013); Hawkins (2012); Michalek (2011); Notter (2010); Baptista (2010)

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Comments

Paul ScottAug 9 2013 02:29 PM

Thanks Max for providing a comprehensive rebuttal to the anti-EV misinformation crowding the media landscape. The oil companies are clearly paying people and institutions to try and put doubts about EVs into people's minds. I even have to fight to convince certain Sierra Club people of EV viability in this regard. Of all people, you'd think they would get it, but the Ozzie Zehner types have put doubt into their heads as well. Please keep up the fight with these good articles!

John A. TamplinAug 10 2013 11:55 AM

The other thing EV opponents ignore is that they don't have to be perfect, just better than the alternatives. Less overall pollution and moving that pollution away from population centers are both good. (As an aside, I find that EV deniers are the same group as vaccine deniers; you would think they would be all over EVs since the number of cars on the road correlates with increased autism just as well as increased use of vaccines).

The other point you didn't mention is that the opponents talk about well-to-wheel efficiency for EVs, but never for ICEs. How much energy from that barrel of oil pumped out of the ground makes it to your car, and how much energy did it take to drill, pump, transport, refine, transport, and pump it into your car? I haven't seen what I considered an unbiased report on that (and I would love to see one), but some of them have suggested that a gas car uses more electricity per mile than an EV does when you count the lifetime energy costs of that gallon of gas.

Barry FitzgeraldAug 10 2013 02:10 PM

Some basic facts: EVs run on what electric is available, it CAN be 100% solar or wind. ICEs can NEVER be run on renewables.
Electricity is easy to transport instantly, fossil fuels require existing or new infrastructure that is never ubiquitous (have to find a station to get some)
Fossil fuels require drilling pumping etc for a fuel that used ONCE. EVs require mining and refining materials to be used and reused ad infinitum. So damage done to the environment is not repeated forever.
Electricity can be generated at your home or in community solar and taken from the grid at a charging station at work.

Trish WeberAug 14 2013 12:47 PM

i have a question - is there a break-even point in terms of miles driven/week where an electric vehicle surpasses a conventional gas-powered vehicle in terms of being cradle-to-grave cleanest?

in 2008 i bought a gasoline-powered honda fit (relatively high mileage for a gas engine) because i drive relatively little on a day-to-day basis and i had heard that hybrids were only a cleaner option if one drives more than 40miles/day or something like that. i don't recall the exact figure but my low driving distance, plus price, tipped me toward the fit. of course this was before the leaf came out or there were really very many viable EV options.

is there truth to this or was i duped by propaganda? i was happy with my purchase at the time as my car was the only gas-powered engine 4-door vehicle that made the top 10 or top 5 greenest vehicles...

i would definitely consider going EV next time though. thanks!

Jon MorganAug 14 2013 01:15 PM

Another question I would love to see answered is how much of an impact there is from the fact that an electric vehicle's batteries have a shorter lifespan than the car itself. While a small, fuel-efficient gasoline car will run for 150K miles or longer, an EV will need a second battery at around 80K or 90K. Is this offset by the additional mechanical work needed to maintain a gasoline vehicle? How much impact does that additional battery actually have?

Max BaumhefnerAug 14 2013 01:15 PM

Good question, Trish. It's not so much miles/week that causes the tipping point, but total miles driven. The consensus of the peer-reviewed literature discussed above is that, early in EV's life, the much lower emissions during the use-phase off-set the higher emissions from the production-phase. In states with cleaner electricity, like California, you'll reach that tipping point more quickly. If you drive less per week than the average person, it'll take a little longer, but you'll still get there. And what really matters is that you've bought a car that will provide substantial environmental benefits during its entire life. You're transforming the vehicle fleet and every mile you drive on electricity as opposed to gasoline is much cleaner.

Max BaumhefnerAug 14 2013 01:31 PM

Also a good question, Jon. The battery is the single largest reason why EVs require more energy to produce (at least with today's technology). Each of the peer-reviewed studies cited above makes different assumptions about battery life, which partially explains why the estimates of cradle-to-grave benefits vary. Bottom line, even the studies that assume short battery lives show life-cycle benefits. Of course, it's too early to know with certainty how long the batteries out there today will last, but the manufacturers are providing 100K mile warranties on the electric powertrains. As noted above, once batteries are no longer suited for automotive purposes, they still retain about 80% of their capacity and will likely be put to work elsewhere. You also raise a good point about the simplicity of electric drive. There are likely some additional environmental benefits in terms of avoided oil changes, spark plugs, hoses, brake pads, clutches, etc.

robert winfieldAug 14 2013 03:36 PM

@Jon Morgan. at present, the Tesla S battery has been estimated to be good for over 700,000 miles. deep cycling and over 3,000 cycles. the Li in them is about 7%. many of the EV owners I know also max out their PV in addition

Kristian HandbergAug 15 2013 07:37 AM

Great article Max tackling a difficult issue. I reached very similar conclusions in a similar study I completed in 2012 (http://goo.gl/Qde1Fo). The transferred impacts arising from battery production remain a bit of a grey area due to the proprietary nature of the process, but the benefits still look likely to fall in favour of PEVs. It is hard to avoid feeling that PEVs are being held to a higher standard...

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