'Plug-In' Cars Seen Saving Millions of Tons of Greenhouse Gases

WASHINGTON — U.S. consumption of petroleum could be reduced by 3 million to 4 million barrels a day if enough Americans purchased "plug-in" hybrid vehicles, environmentalists and power industry researchers said Thursday.

And, they said, the reduction could be achieved by only slightly increasing the load on electric power plants.

The net effect would also be an annual reduction of hundreds of millions of tons of planet-heating greenhouse gases, according to a study released jointly by the Natural Resources Defense Council and the Electric Power Research Institute.

"Plug-in" hybrid vehicles, or PHEVs, would operate on electric motors and internal combustion engines, similar to the conventional hybrid electric vehicles now on the road.

However, they would have batteries – not yet commercially available – that could be charged overnight from the electric power grid.

The analysis is the first to combine detailed computer modeling of the electric power system, the transportation sector and air quality models, officials from NRDC and the power industry research group, known as EPRI, said at a press conference.

Assuming there is no improvement in the efficiency of today's electric power plants, the impact by 2050 on greenhouse gases would be slight, they said.

However, with "medium range" improvements in the environmental impact of power generation and widespread use of PHEVs, the net effect on global warming would be a reduction of nearly 500 million tons of carbon dioxide a year.

That would be equivalent to eliminating over 80 million gasoline powered vehicles — or roughly one-third of the existing U.S. fleet.

And the increased load on the national electric power grid would be only 7 percent or 8 percent, the analysis concluded.

If plug-ins used electricity from a new generation of efficient coal-fired power plants capable of capturing and storing carbon dioxide, each vehicle would result in about 37 percent less greenhouse gas than is now released by a conventional hybrid, authors of the study said.

Since motor vehicles do not release mercury into the atmosphere and coal burning power plants do, the change would lead to increased mercury pollution unless means are found to remove the metal from power plant smokestacks, they reported.

"The key to this is cleaner electric power plants," said Dan Lashoff, science director of NRDC.

Roger Duncan, deputy general manager of Austin Energy in Texas, which through its Plug-in Partners campaign has been the country's leading advocate of PHEVs, said the study shows that the vehicles would be "a major solution to the climate crisis we are facing."

Duncan attended the press conference at the National Press Club to announce the results of the study.

"When I sat in this room 18 months ago and we kicked off the Plug-in Partners campaign, I said that we needed an objective study to answer questions about whether these vehicles would result in overall reductions in greenhouse gases or merely shift the load from the transportation to the electric power sector," he said.

"This study does that," he added.

The United States uses 21 million barrels of petroleum per day and emits a variety of greenhouse gases which have the overall heat-trapping capacity of nearly 8 billion tons of carbon dioxide, according to the government's Energy Information Administration.

The study can be read at www.epri-reports.org.