by Don Anair, via Union of Concerned Scientists
The longer you own an electric vehicle, the lower its global warming emissions are likely to become. Why? As some of the oldest, dirtiest coal plants are being retired and investments in renewable electricity increase, the global warming emissions that result from generating a given amount of electricity are estimated to fall nationwide by an average of about 13 percent by 2025.
That means, for 70 percent of Americans, charging their electric vehicle (EV) on the regional electricity grid in 2025 would result in lower global warming emissions than even today’s most efficient gasoline hybrid, the 50 mpg Prius. While that’s good news, it could be even better. By investing in more renewables and retiring more coal plants over the next decade, using electricity as a transportation fuel would deliver even greater global warming benefits than projected.
How will changes in the grid affect the emissions from charging an EV?
To get an idea of how emissions from charging an EV may change in the coming years, I looked to the Annual Energy Outlook updated most recently in June of this year by the U.S. Energy Information Administration (EIA). The outlook projects changes in the electricity grid expected in the coming years as a result of varying energy demand, regulatory drivers, expected power plant retirements, and other factors.
Using the same well-to-wheels methodology used in our State of Charge report (more on this in the notes below), and the Annual Energy Outlook’s projections for 2025, I estimated how the emissions from charging an EV powered by the grid in 2025 compare to the emissions of a gasoline vehicle. I did this analysis across each of the grid regions across the United States, excluding Hawaii and Alaska for which projections were unavailable.
For each region, I show the miles per gallon that a gasoline vehicle would need to achieve to have emissions similar to an EV powered on the electricity grid (see the map below). For example, charging an EV in Massachusetts on the 2009 regional (NEWE) electricity grid (the most recent year for which we have data) would create about the same global warming emissions as driving a gasoline vehicle that gets 75 mile per gallon. That’s better than any gasoline or hybrid vehicle on the market. In 2025, as the grid in Massachusetts gets cleaner, that same electric vehicle would be responsible for about the same emissions as a gas-powered vehicle with the astounding fuel economy of 106 mpg.
The maps show how EV emissions stack up across the country, with current data and projecting to 2025. Both maps stick with the same GOOD, BETTER, BEST ratings we used in State of Charge, where BEST means an EV has lower emissions than the even the most fuel efficient gasoline hybrid available today (50 mpg). By 2025, four additional regions move into the BEST category and another three move from GOOD to BETTER. A closer look at the map reveals the change in mpg ratings, and shows every regional electricity grid getting cleaner between 2009 and 2025
If the population distribution remains similar, 70 percent of Americans will live in BEST regions by 2025, where a grid powered EV will emit less global warming emissions than a 50 mpg gasoline vehicle. That holds true for about 45 percent of Americans today.
The improvement in emissions is expected as regions around the country clean up their electricity grids. EIA projections show renewables increasing their share of national electricity generation from about 11 percent in 2009 to about 15 percent in 2025. The projections also show the share of our grid powered by coal, the largest source of global warming emissions from electricity production, decreases from 44 percent in 2009 to about 38 percent in 2025.
National numbers don’t tell the whole story
These national figures are positive, but they don’t reflect the magnitude of what’s happening in many regions.
For example, the California grid region is expected to reach 35 percent of its electricity from renewables by 2025, a large change prompted by a strong state Renewable Electricity Standard (RES). As a result, the mpg equivalent of an EV in California is well over 100 mpg by 2025.
In contrast, the Rocky Mountain grid region (RMPA on the map) also sees relatively strong growth in renewable electricity, increasing to about 17 percent of its electricity generation by 2025 from about 10 percent in 2009. But the region remains in the GOOD category as a result of a continued reliance on coal for the vast majority of its electricity needs.
The future has yet to be written
Clean electricity policies are driving the grid in the right direction, meaning an EV bought today is likely to have lower global warming emissions over time.
Some regions are lagging behind, but we have opportunities to change that. In Michigan, currently classified as a GOOD region, a renewable energy standard is likely headed for the ballot this fall. According to a letter from experts across Michigan, the 25% renewable electricity by 2025 standard will not only reduce global warming emissions, but will create jobs, reduce air pollution, and boost the state’s economy.
State and federal renewable energy policies are critical for cleaning up the grid and unleashing the full potential of EVs. The future state of charge looks strong, and with the right policies in place will only get better.
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Language Intelligence: Lessons on persuasion from Jesus, Shakespeare, Lincoln, and Lady Gaga
So we are bent on keeping the car fleet running on a different fuel because after all, ‘The American way of life is not negotiable,’ right? The question of whether cars should even have a place in our energy constrained future does not get asked.
What about the fact that most Americans cannot be expected to afford the purchase of a new car ‘upgrade?’ Or do we only care about the reasonably well-off?
What about the fact that most of the GHGs come from the manufacturing of the vehicle?
What of the burden of maintaining our crumbling, melting, obsolete highway system made of oil, serviced with oil?
We wouldn’t want to bother talking about massive social change would we? How forward-thinking do you think we will appear to posterity?
“It is the omnipresent affirmation of the choices that have already been made in the sphere of production and in the
consumption implied by that production”- Guy Debord
Hear hear
The simply, undisputable fact is that every new electric vehicle that hits the road, pushes back the day when our power grid will finally be 100% sustainable, carbon-free.
There is no such thing as a “green” car.
Last time I checked there was no set date that you had to go out and buy yourself and EV. You can keep driving a gas car if you enjoy paying 4 bucks a gallon for gas. I pay ten cents to charge my vehicle, 10 cents takes me 40 miles. The fact of the matter is oil is running out. I’m 20 years old and experts are predicting oil will run out in my lifetime. So explain to me sir, If we don’t invest our time and money in alternative fuel sources, what will happen to our society when the oil runs out?
Great analysis. EV’s clearly make a significant contribution, however, for them to make the impact, there must be a sufficient number of them on the road. There in lies the problem. Prices must come down, which translates into lower cost for batteries. The administration made a concerted effort to help the battery industry bring down the cost of batteries –but the results so far have been mixed. The second concern is “range anxiety.” Many americans are very concerned about the limited range of EV’s even though studies have repeatedly shown that the range of an EV is more than adequate to meet most driving needs, particularly around urban centers. Finally, vast progress must be made in the charging infrastructure to alleviate concerns of folks that may get stuck in a EV with a discharged battery and no convenient place to charge it.
The EV is a nice idea – and the article was appropriately specific to the issue at hand – but there are many issues that would need to be dealt with if EVs became the norm – such as the ability of the GRID to handle the load – better to just reduce car usage and reduce consumptive growth overall.
Of course if you have already selected a 100% renewable wind power supplier for your electricity (there are two competing 100% renewable wind power providers in my area) then your electric car will be a truly zero emission vehicle.
One of those suppliers is selling 100% renewable wind power for slightly less than my utility’s conventional electricity rate.
Based on a cursory review of the report cited, it appears that a significant portion of the future reduction of CO2 generation associated with electricity production is attributable to the replacement of coal by shale gas.
It would behoove those who oppose fracking to consider this.
Well, James, would it not be even better to replace coal with real renewables, like solar, wind, tidal, geothermal etc, and energy efficiency and reduced consumption, and do without the ‘frack cocaine’ of gas obtained at the cost of massive pollution, waste of precious water, increased risk of earthquake and the very real greenhouse menace of methane emissions?