Report: Plug-in electric cars not the greenest choice in Iowa

Buying a hybrid electric vehicle like the Toyota Prius or even a gas-powered Kia Rio would be a more "climate-friendly" for Iowans than buying one of the new plug-in-electric cars, a new report says.

Iowa is one of 36 states in which the most efficient hybrid vehicles generate less greenhouse gas emissions than plug-in electric cars, according to the report.

The Chevrolet Volt and Nissan Leaf are leaders in a new generation of plug-in vehicles that run entirely or mainly on grid power stored in a battery. They've won acclaim as the greenest cars, but a report from New Jersey-based Climate Central says that all depends on where you live and drive the car.

Instead of analyzing only tailpipe emissions from the cars, the report analyzed "life-cycle emissions" that also included the greenhouse gases produced in producing and distributing its fuel, whether it be gas, diesel or electricity.

Seventy-two percent of Iowa's electricity is generated from coal-burning power plants, the group said, well above the national average. Coal combustion creates more carbon dioxide emissions blamed for climate change than any other type of power plant fuel, the group said.

The humble Kia Rio with a manual transmission, Hyundai Accent with a manual transmission and Scion IQ are conventional gas-powered cars that have lower carbon dioxide emissions per mile than the all-electric Nissan Leaf when the Leaf is charged on Iowa's power grid.

The analysis shows that a Nissan Leaf emits .77 pounds of carbon dioxide per mile based on the coal-heavy electric generation mix in Iowa.

A Toyota Prius, by comparison, emits an average of .52 pounds of carbon dioxide per mile, the lowest of any mass-market car.

The analysis found five other hybrid models also had less carbon dioxide emissions per mile traveled than the all-electric Nissan Leaf.

"Consumers have a lot of choices for climate-friendly vehicles," said Alyson Kenward, a research and communications scientist for the group in Palo Alto, Calif. "Depending on where you live, a hybrid or even a gas-powered vehicle might be more climate-friendly than a plug-in electric car."

Dave Wright Nissan-Subaru in Cedar Rapids has had a demonstrator model of the Nissan Leaf on hand, and has a waiting list of buyers who've signed up for the plug-in electric vehicle.

Dealer Dave Wright had doubts that the study included such variables as the Leaf's lack of need for motor oil in the sustainability equation. He said the Leaf's strong appeal includes such factor as lower fueling costs than gasoline cars and the ability to warm up the car's interior on a cold day without producing tailpipe emissions.

The analysis was based on statewide data regarding electric power generation. Kenward said the actual generation mix from a plug-in electric car driver's particular local utility could be different.

The study used the Nissan Leaf as its benchmark for plug-in electric vehicles because the EPA has compared it to other vehicles for emissions, and because it is more similar in price and size to the Prius than other all-electric cars, Kenward said.

The group said coal-fired generating plants have the biggest carbon dioxide emissions profile of any electric generation source. In states like Wyoming or Indiana that derive 90 percent of their electricity from burning coal, driving a Nissan Leaf hybrid would emit more carbon dioxide per mile of travel (about .9 pounds) than driving a Toyota Prius (about .5 pounds).

The Nissan Leaf still comes out the winner in carbon emissions in states like Connecticut that get much of their power from nuclear plants, or like Washington that receive much of their power from hydroelectric dams.

In addition to the Nissan Leaf, the group's analysis also examined the greenhouse gas emissions of the plug-in Chevrolet Volt.

Chevrolet's Volt uses different technology than the Leaf. It has a gasoline-powered generator that recharges the battery system so that the vehicle's electric engine can continue running beyond the range permitted by its initial plug-in charge.

The technology made the Volt hard to compare to other vehicles like the Prius. If the driver relied on the gasoline engine during half of the miles traveled, the study said the Prius would be a better bet for greenhouse gas emissions in 45 states.

Nissan and General Motors spokesmen did not return calls and e-mails seeking comment.

Sales of the Prius have been running strong locally and nationally as consumers react to high gas prices.

Cars more climate-friendly than Nissan Leaf

(based on Iowa's electric power sources)

Toyota Prius

Honda Civic hybrid

Lexus CT 200h hybrid

Toyota Prius V

Ford Fusion hybrid

Lincoln MKZ hybrid

Scion IQ

Chevrolet Volt

Hyundai Accent

Kia Rio