Study Finds Plug-In Hybrids With Lots of All-Electric Range Won't Be Cost-Effective
By John O'Dell February 26, 2009Weight, Price Penalty for 40 Miles of All-Electric Range Is Prohibitive, Researchers Say
By John O'Dell, Senior Editor
In a report sure to be a blow to GM's hopes for its upcoming plug-in hybrid, researchers at Carnegie Mellon University have found that the extra cost and weight of the
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Researchers say vehicles like the the Chevy Volt may be too much of a good thing.
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batteries a vehicle such as the Chevrolet Volt must carry to achieve its targeted 40 miles of all-electric range make it too expensive to be cost-effective transportation for most people.
The report, to be published in a future issue of the journal "Energy Policy," doesn't identify the Volt by name but compares a plug-in hybrid with its basic characteristics to conventional hybrids, other plug-ins with less electric range, and even conventional vehicles.
"Large-capacity PHEVs sized for 40 or more miles of electric-only travel are not cost-effective in any scenario," the report's authors insist.
Bloomberg News issued the first report on the study today.
Fuel Savings Not There
General Motors Corp. has designed the Volt to travel up to 40 miles on a fully charged battery pack before its auxiliary gasoline engine-generator kicks in.
The automaker says that because the average American drives less the 40 miles a day when commuting or using the vehicle for normal household errands, the Volt will be highly fuel-efficient and will run as a zero-emissions vehicle for much of its time on the road.
That may be true, the Carnegie Mellon researchers say in their study of plug-in hybrid cost-effectiveness, but if an owner hopes to recoup ownership costs from fuel savings, a rechargeable hybrid vehicle capable of that much all-electric range isn't the answer.
"Forty miles might be a sweet spot for making sure a lot of people get to work without using gasoline, but you're doing it at a cost that will never be repaid in fuel savings," Jeremy Michalek, an engineering professor who led the study, told Bloomberg News in an interview.
Plug-In Choices Coming
Bloomberg characterized the study as an effort to test how prices and driving habits could shape consumers' choices as the variety of hybrid-electric vehicles increases and General Motors, Toyota Motor Corp. and Ford Motor Co. all promise to bring plug-in hybrids with extended all-electric range into the mix in coming years.
A plug-in with 7 to 10 miles of electric range, or any conventional hybrid, might provide the best mix of price, faster charge times and fuel-efficiency, Michalek said.
Bloomberg cites "current industry and academic estimates" in figuring the cost of the Volt's 400-pound lithium-ion battery pack at about $16,000.
GM also is developing a plug-in version of its Saturn Vue hybrids that will have just 7 miles of all-electric range.
Toyota, whose conventional hybrids last year accounted for 83 percent of all hybrids sold in the U.S. (the Prius alone accounted for about 55 percent of the market), is introducing the redesigned 2010 Prius this summer that will achieve an estimate 50 miles per gallon and can travel for a new miles in all-electric range at speeds of up to about 25 miles an hour.
The automaker plans to introduce a limited-production plug-in Prius late this year for testing in commercial fleets.
It will be outfitted with lithium-ion batteries for more all-electric range, but likely will not be able to travel more than 20 miles before the initial charge is depeleted and it reverts to conventional hybrid operation.
Ford also plans a plug-in hybrid, most likely a version of its Escape SUV, for retail sales in 2012. Like the Prius, it will have a relatively short all-electric range and will use its batteries and electric motor instead to augment the gas engine for overall improved fuel economy.
Pollution Benefits
While so-called long-range plug-ins such as the Volt may not pay for themselves with fuel savings, the Carnegie Mellon researchers do find that they "could minimize [greenhouse gas] emissions for some drivers and provide potential to shift air pollutant emissions away from population centers."
GM has said it will launch the Volt by the end of next year. Pricing hasn't been set, but company insiders have said that the extended-range plug-in is likely to cost around $40,000 before a $7,500 federal income tax credit is applied.
One scenario the university researchers didn't address in their study is the impact that nationwide gasoline shortages and rationing would have on the cost-effectiveness of a vehicle that can run a substantial distance on its grid-charged batteries before requiring a petroleum engine assist.
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Edmunds AutoObserver looks at how Carnegie Mellon study is affecting GM's stock price.
LEAVE A COMMENT
Click here to comment on this entry.The problem with this analysis is that it misses out entirely on the point of a plug-in electric: fuel savings. That's not the same as determining a cost-benefit analysis. The idea is to use less fuel to serve the purpose of meeting national security needs, i.e. reducing the need for foreign oil. Eventually, the technology will progress further and meet the cost-benefit analysis too. Or we could just keep kicking the can down the road. Fortunately, this Ivory Tower dweller will have little or no impact on whether or not the Volt and other plug-ins are introduced.
The problem with this analysis is that it misses out entirely on the point of a plug-in electric: fuel savings. That's not the same as determining a cost-benefit analysis. The idea is to use less fuel to serve the purpose of meeting national security needs, i.e. reducing the need for foreign oil. Eventually, the technology will progress further and meet the cost-benefit analysis too. Or we could just keep kicking the can down the road. Fortunately, this Ivory Tower dweller will have little or no impact on whether or not the Volt and other plug-ins are introduced.
[from article]..if an owner hopes to recoup ownership costs from fuel savings, a rechargeable hybrid vehicle capable of that much all-electric range isn't the answer. "Forty miles might be a sweet spot for making sure a lot of people get to work without using gasoline, but you're doing it at a cost that will never be repaid in fuel savings"..
To which I must ask, when /will/ it become "the answer"? Never say "never", Mr. Michalek.
GM's analysis resulted in the easily understood benchmark of a 40 mile range to keep most commuters on pure electric drive. That variable won't change significantly over time. However, the costs of the resources needed to build and operate a plug-in hybrid car will change. At some point in the future, batteries will become cheap enough, and gas expensive enough, that the Volt will be the answer. But where in the battery vs. gas cost equation is that break-even point? THAT would be useful information.
A couple more things to consider.
Assertion 1: The vast majority of hybrid vehicle owners have not run the ROI calculation for the added cost of the hybrid drivetrain. Just like anyone else who pays a premium for extreme performance, they bought the car as a form of self expression. And, yes, fuel mileage /is/ a performance criteria. The Prius has been a success because, in addition to having the performance numbers on paper, you can SEE the performance in the shape of the car.
Assertion 2: Every ROI calculation I've read about allocates $0 to the resale value of the hybrid drivetrain. Example: "At current gas prices, driving 15,000 miles a year, you?ll need to own the InsertHybridCarHere for 15 years to recoup the added cost of the hybrid drive system vs. its standard drive counterpart." Or some such thing. Who cares?! What matters is that they saved money on gas while they owned the car, they enjoyed the distinction, and they were also able to sell it on the used car market for a premium over the standard model. Ultimately, if we really want to split hairs about the ROI of hybrid systems, it must be done in the context of the expected life of the vehicle, which could be 300K miles or more, rather than the expected ownership period of the poor sap that drove it off the dealer lot with only 5 mi on the odo. Will a hybrid car go 15 yr x 15,000 mi/yr = 225,000 mi before croaking? Probably. Will all of it?s owners feel better for using fewer non-renewable resources? Absolutely.
Great piece John. It's great to see some more light shed on the complexity of plug-ins. They can provide some great benefits in the near-term. But longer-term, you're going to need some additional options.
This study confirms what the National Hydrogen Association has been saying for a while that long-term, you're going to need something else besides just batteries to design the kind of multi-purpose cars most car buyers want to buy. For a 300-mile range family-sized car, even the best batteries will weigh twice as much and take up twice the size of a hydrogen system. http://hydrogenassociation.org/webinar/archives/23oct08_slides.pdf
But as this article points out, a balance that isn't "heavy" on batteries could work well with gasoline engines or ethanol engines or hydrogen fuel cells. Using these technologies smartly and in organized succession could really reduce emissions and oil use--and some green jobs too!
Hey here's a thought - If some cars offer 4, 6 and even 8 cylinder engines as options why not offer 10, 20 and 40 mile range "battery pack options"?
Probably will not pencil out, but would think that there could be some battery weight/cost savings.
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