When it comes to cost and global warming emissions, electric vehicles in the United States lead double lives, according to a new study by the Union of Concerned Scientists (UCS).

An all-electric Nissan Leaf in Buffalo, N.Y., emits relatively few greenhouse gases, equal to the amount produced by a gasoline-powered car getting 86 mpg. But in Denver, the same Leaf is equivalent to only a 33-mpg vehicle, such as a subcompact Ford Fiesta.

The degree to which electric vehicles, or EVs, affect the climate depends on the whether they're charged by power plants running on fossil fuels or cleaner energy sources, including solar, wind, nuclear and natural gas.

With many of these new, highly efficient cars now on the market, including the General Motors Co. Chevrolet Volt, Ford Focus Electric and Toyota Prius Plug-in Hybrid, consumers may want to know just how much they'll be saving in fuel and carbon dioxide emissions by driving an EV in their area.

In breaking down the United States region by region, the group concluded that 45 percent of Americans live in areas where EVs emit lower levels of greenhouse gases than a conventional 50 mpg vehicle. That puts them ahead of even the most efficient gasoline-powered hybrids.

Another 37 percent of the U.S. population lives in areas where EVs have emissions similar to those of a vehicle with a 41- to 50-mpg rating, such as the popular Toyota Prius.

"This report shows drivers should feel confident that owning an electric vehicle is a good choice for reducing global warming pollution, cutting fuel costs and slashing oil consumption," said Don Anair, the report's author and senior engineer for UCS's Clean Vehicles Program.

"Those in the market for a new car may have been uncertain how the global warming emissions and fuel costs of EVs stack up to gasoline-powered vehicles. Now, drivers can for the first time see just how much driving an electric vehicle in their hometown will lower global warming emissions and save them money on fuel costs," he said.

Even in parts of the country where coal makes up most of the electricity supply, EVs produce the same amount of greenhouse gases as the best gasoline-powered nonhybrid vehicles that get about 33 mpg.

Cost savings of EVs don't come quickly
Unlike an internal combustion engine vehicle, "an EV purchased today can have lower global warming emissions as it gets older," said Anair.

As the nation's aging power grid is upgraded with cleaner energy sources -- spurred by federal and state-level regulations on air pollution, renewable portfolio standards and tax credits -- the emissions profiles of EVs across the country are expected to improve.

The study finds that by 2020, the greenhouse gas emissions intensity of electricity generation in certain areas will have improved by as much as 30 percent over 2010 levels.

Like fuel efficiency, the cost of electric cars is also tied to the grid.

Based on electricity rates in 50 cities across the United States, UCS researchers found that EV owners could save $750 to $1,200 per year compared with operating the average new gas-powered car with fuel at $3.50 per gallon.

But saving enough to overcome the upfront cost of an EV takes time. The automotive research website Edmunds.com found that even if gas prices hit $5 per gallon, the payback period for the Chevrolet Volt would take nine years compared with a same-size gas-powered vehicle.

EVs good on emissions, cost and national security
For business and military leaders who met yesterday at the Hudson Institute, the real savings from EVs come at the national level.

Frederick Smith, president and CEO of FedEx Corp. and a member of the Energy Security Leadership Council, said that electrifying light-duty vehicles "as rapidly as possible" should be one of the country's main strategies to reduce U.S. dependence on foreign oil.

Of the just under 19 million barrels of oil used in the United States each day -- about 20 percent of the global demand -- 70 percent goes toward transportation, said Smith. And while U.S. oil dependence remains high, fuel prices are climbing.

Former General Motors Vice Chairman Robert Lutz echoed Smith's call for increased electrification of transportation in the United States but denounced the way EVs have been portrayed by the environmental community and criticized by right-wing pundits.

"To me, the unfortunate thing is that because electric cars are very closely associated with the left-wing environmental green movement and to combating global warming and reducing CO2, the idea of vehicle electrification triggers this visceral reaction on the part of conservatives, which is, 'If it's electric, it must be a product of the Democratic left-wing environmental machine, and therefore, we hate it,'" he said.

For Lutz, EVs are not really about curbing greenhouse gas emissions or saving money at the pump. "What these vehicles are about is shifting portions of the American mobile sector onto a more efficient and domestically produced power source," he said.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500