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USA Today's Misplaced Criticisms of PHEV Emissions
Feb 26, 2008 (From the CalCars-News archive)
This posting originally appeared at CalCars-News, our newsletter of breaking CalCars and plug-in hybrid news. View the original posting here.
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USA Today automotive reporter Jim Healey was quite positive about the test drives he took in Ford and Toyota prototype PHEVs in January:­calcars-news/­911.html

Now he's gone back to several reports released months ago, including one by the Electric Power Research Institute and the Natural Resources Defense Council, and selectively cherry-picked the most unlikely scenarios under which coal could be the culprit for PHEVs resulting in higher emissions. While eliciting worst-case comments from NRDC, he failed to ask EPRI for its views.

This may be simply be a journalist's report, or it could signal the beginning of a sustained effort by a range of liquid fuel advocates to attempt to slow the growing momentum of support for the electrification of transportation.

Within 18 hours of the article appearing, over 350 responses appeared on the website. Below is the story followed by our brief comments and some posted to the site by Sherry Boschert, author of Plug-In Hybrids. We expect to point our readers to further responses from EPRI and NRDC.

Plug-in cars could actually increase air pollution By James R. Healey, USA TODAY February 25, 2008­tech/­products/­environment/­2008-02-25-plug-in-hybrids-pollution_N.htm

The expected introduction of plug-in hybrid electric vehicles could cut U.S. gasoline use but could increase deadly air pollution in some areas, two reports say.

That's because a plug-in's lower tailpipe emissions may be offset by smokestack emissions from the utility generating plants supplying electricity to recharge the big batteries that allow plug-ins to run up to 40 miles without kicking on their gasoline engines. Plug-ins, called PHEVs, are partly powered, in effect, by the fuel used to generate the electricity.

About 49% of U.S. electricity is generated using coal, so in some regions a plug-in running on its batteries is nearly the equivalent of a coal-burning vehicle. The trade-off is one that even plug-in backers acknowledge. It could undercut the appeal of vehicles that appear capable of using no gasoline in town and hitting 50 to 100 mpg overall fuel economy.

If large numbers of plug-in hybrids were being recharged with power from the least-sophisticated coal plants, "There is a possibility for significant increases of soot and mercury," says a report by environmental advocacy group Natural Resources Defense Council. Soot particles can make it hard to breathe, especially for asthmatics. Mercury is toxic.

"Plug-in hybrids are perhaps not good for all areas," says Howard Learner, executive director of the Environmental Law & Policy Center, a Chicago-based advocacy group. In "states that are heavily coal, that equation doesn't work out very well for the environment."

After PHEVs drain their stored energy, they operate like conventional hybrids, triggering their gasoline engines to help drive the wheels and recharge the batteries. Conventionals can't be plugged in; their batteries are recharged only while driving.

The longer a plug-in is designed to operate on just the batteries, the less gasoline it uses, but the more electricity it needs to recharge the larger batteries.

Thus, the better the PHEV that is, the longer it goes just on its batteries the greater the charge required and the more the pollution that might result from an electric utility's power generation.

Learner calls PHEVs "really important emerging technology where the cleaner technologies are used to charge them."

Sulfur dioxide also may be an issue

A study by the Minnesota Pollution Control Agency found plug-ins also could result in more sulfur dioxide (SO2) emissions. SO2 is toxic in large amounts and is a component of corrosive acid rain.

The Minnesota study found that use of PHEVs would lower most emissions compared with other vehicles, but that resulting SO2 emissions would be more than double those from gasoline vehicles and about three or four times greater than from driving a regular hybrid. Exactly how much depends on how far the PHEV can run on battery power alone.

The Minnesota study also found that PHEVs would emit more carbon dioxide (CO2) than driving a conventional hybrid. CO2 is a greenhouse gas thought to contribute to global warming.

The Minnesota numbers are striking because they predict the big jump in SO2 even if 40% of the state's electricity were generated by wind power, not coal or other polluting fuels. About 4% of the state's electricity now is from wind, according to state officials.

The state's PHEV study concludes: "Alternative vehicles offer benefits, but no single technology currently stands out as a clear choice."

The NRDC calculus shows that a plug-in charged from a power plant burning the dirtiest type of coal still has an overall pollution level less than a conventional gasoline car. But it would produce 11% more greenhouse gas emissions than a regular, non-plug-in hybrid, according to Luke Tonachel, vehicles analyst at the NRDC and co-author of the group's report on plug-ins. The report was produced jointly with the non-profit Electric Power Research Institute.

He says, however, that charging a plug-in with electricity from renewable resources wind or water, for instance cuts overall greenhouse gas emissions to as low as a conventional gasoline car getting 74 mpg. No current gasoline car does that.

The NRDC and Minnesota studies were published last year but have yet to trigger alarms. PHEVs still are experimental; their possible threat is distant.

"It seems a little premature to think of it being a problem but there are a lot of issues we should have been thinking of sooner," says Charles Griffith, auto project director at the Ecology Center, an environmental non-profit based in Michigan. He cites as an example debate over use of land to grow crops for ethanol fuel vs. for food.

Even so, Griffith says, "The scenario where there are so many plug-in hybrids plugged into the (electric power) grid that you'll see a change in air quality just doesn't sound true to me."

Plug-ins may be on streets soon

Automakers say PHEVs could be on the streets in significant numbers within five years. Prototypes being tested by car companies suggest they should be able to go up to 40 miles on battery power, which could enable them to deliver average mileage in the neighborhood of 100 mpg in general driving.

The first plug-in vehicle in production, however, is likely to be General Motors' Chevrolet Volt, which is not a hybrid. Due in 2010 or 2011,Volt runs entirely on battery power. Like PHEVs, its battery pack can be recharged by plugging into a normal outlet, using electricity from a utility generating plant. A small gasoline engine recharges Volt's batteries when an outlet isn't handy, but unlike in a hybrid, that engine never directly powers the car. GM could sell 60,000 or more a year, forecasts consultant J.D. Power and Associates, if the price is $30,000 or less.

GM said at the Detroit auto show in January that it also will produce a plug-in hybrid version of its Saturn Vue SUV near the same time Volt is to launch.

Toyota Motor and Ford Motor each showed a prototype plug-in hybrid at auto shows this year and will test the designs. "It will come," says Toyota's Jaycie Chitwood, senior planner at the automaker's advanced technologies unit in the USA. "It's more a question of 'when' than 'if.' "

Ford's Greg Frenette, chief engineer of zero-emission vehicles, says it should take no more than five years to decide if plug-ins can be made reliable and inexpensive enough.

The U.S. Energy Department is backing PHEVs.

In January it offered $30 million for projects to "deliver up to 40 miles of electric range without recharging" and to make plug-ins "cost-competitive by 2014 and ready for commercialization by 2016."

"We look at plug-in hybrids as the next generation of hybrids. They run cleaner, they save oil and they can save consumers money at the pump," NRDC's Tonachel says. But, he says, "Until our oldest power plants are replaced or upgraded, there could be increases in local particulate matter and ozone."


The groundbreaking EPRI-NRDC that is the basis for much of this journalist's report really amounted to a series of models and projections for how the US power generation industry will evolve and how plug-in hybrids will come into the marketplace. Under every realistic scenario, PHEVs will bring substantial environmental benefits. (See our summary and links to the original report in our June 19, 2007 posting at­calcars-news/­797.html .)

Models of this system show greenhouse gas improvements for PHEVs in every region of the country, for every scenario reviewed, even the ones that assumed the least progress in the electric sector for improved technology, emissions, and efficiency.

The USA Today report in discussing non-greenhouse gases doesn't recognize that the "dirty coal plants" are on the way out, and that "criteria pollutants" are already capped by the Clean Air Interstate Rule.

PHEVs won't arrive in volume for some years, and by the time they are in widespread use, there will be fewer and fewer dirty-coal plants providing night-time power.

That's why electric drive vehicles are the only vehicles that can get cleaner as they get older because the power grid gets cleaner.


I wonder if Mr. Healey bothered to read the NRDC study, and if he's ever heard of the EPA. And I wish the headline writer hadn't confused local results with national ones.
- The NRDC/EPRI study concluded that NATIONALLY, all emissions (including carbon dioxide) will decrease with plug-in hybrids, even though a few small pockets of the country near old coal plants could see a few increased emissions ASSUMING that we increase our overall use of coal to 60% of electricity (when in reality, we are moving away from coal). For my summary of this and more than 40 other studies of emissions from plug-in vehicles, see­images/­EmissionsSummary.pdf
- The Minnesota study (which I just read, and is not yet in my summary) reports local emissions, not national ones. It concludes that with heavy coal use (60%), plug-in hybrids reduce all emissions compared with today's cars except for sulfur oxide (SOx) emissions. Lots of other studies have found that same theoretical increase in SOx with plug-in cars, but in the real world (which the reporter ignored), the federal Environmental Protection Agency has laws and regulations that limit power-plant emissions. As a result, as our energy-hungry society produced more and more electricity between 1993 and 2004, SOx emissions fell from 15 million down to 10 million metric tons per year. No matter how much more electricity we produce, SOx emissions will continue to decline if the regulations continue to be enforced.
- The Minnesota study also has a hypothetical scenario in which the only cars out there are hybrids. Compared with them, and using 60% coal electricity, plug-in hybrids theoretically increase SOx (but not really, see above), and could increase carbon dioxide emissions by 0.5% -- or 1/500th more than hybrids. Essentially, the greenhouse gases would be the same, and that's assuming that in the decades it will take for all cars on the road in Minnesota to become either hybrids or plug-in hybrids, we make no other advances in limiting the use of dirty, nasty coal. (If that happens, the planet is toast, no matter what we drive.) The Minnesota study says nothing about the greater reductions in carbon dioxide on a NATIONAL scale if we had plug-in hybrids, nor about the benefits of using far less imported, expensive gasoline with plug-in hybrids compared with conventional hybrids.

I'm sure the oil companies will spread this unfortunate article far and wide. As a member of the California Sierra Club's Climate-Energy Committee, I'm going to have to do a lot of re-education of any environmentalist friends who've read it.

Sherry Boschert, author Plug-in Hybrids: The Cars That Will Recharge America

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