WASHINGTON – A bipartisan group of lawmakers have produced a behind-the-scenes agreement aimed at ramping up fuel economy on autos and sport utility vehicles. Hopes are it will be attached successfully to the sweeping energy bill now being debated.

The compromise includes a measure originally co-sponsored by Sen. Dianne Feinstein, D-Calif., and Maine Republican Sens. Olympia Snowe and Susan Collins that seeks to redefine SUVs as passenger vehicles rather than “commercial vehicles,” which are required to meet less-stringent efficiency goals.

The agreement also would adjust corporate average fuel economy standards by requiring auto manufacturers to boost efficiency on their vehicles by an average of 36 miles per gallon. The new rule would be phased in from 2007 to 2015, with progress closely monitored by the National Highway Traffic Safety Administration.

The proposal, which also melds two different measures originally proposed by Sen. John Kerry, D- Mass., and Sen. John McCain. R-Ariz., calls for pacing increases in fuel economy so 40 percent of the improvements would be reached by 2010.

“We’ve got to take our nation’s energy engine out of reverse – by closing the ‘SUV loophole’ Senator Feinstein and I targeted – and then by taking the next appropriate step by raising fuel standards for passenger cars as well,” Snowe said in a statement.

Collins, who also has been drumming up support for the measure, predicted the legislation would save more than 1 million barrels of oil a day by 2015.

“This will give America rapid and substantial oil savings in a matter of only a few years and provide more and more oil savings for each year thereafter,” she said.

Environmental lobbyists cheered the compromise agreement, but the measure faces strong resistance from both the White House and lawmakers representing auto-producing states who joined House Republicans last August to thwart a similar effort.

The Alliance of Automobile Manufacturers, a trade group, calls the CAFE standards a “failed” program consumers don’t care about. What’s more, the association believes any legislative effort to increase fuel efficiency further would spell disaster for the SUV market.

“They ought to call this the SUV and pickup truck elimination act of 2002,” said alliance spokesman Eron Shosteck. “It takes a certain amount of energy to move a heavier vehicle down the road and we will never be able to get what they are asking for without taking the features out that consumers demand.”

Shosteck said fuel-efficiency laws simply force manufacturers to produce cars that consumers won’t buy. “If consumers want highly efficient cars, they are out there,” he said, “but our top 10 fuel-efficient cars account for only 2 percent of our entire sales.”

Supporters of stricter standards note that the auto industry made similar protests when fuel standards first were proposed in the 1970s during the Arab oil embargo.

They also have been emboldened by a National Academy of Sciences study released last summer that claims automakers can boost their vehicles’ fuel efficiency through existing technologies by 36 percent over the next 15 years.

Opponents find fodder for their arguments in the same study. Any boost in fuel efficiency also could cause an increase in traffic deaths and add hundreds of dollars to the cost of a new vehicle, the study found.

Under the compromise legislation, car and light truck fleets would be required to achieve a unified fuel economy standard after model year 2010. The legislation exempts large “workhorse” trucks from new fuel economy requirements, and utilizes exemptions already provided for in EPA regulations for medium-duty passenger vehicles. The provision accommodates the needs of work trucks as originally intended under CAFE standards while bringing the new, largest class of SUVs – such as the Ford Excursion and Humvee, whose fuel economy currently is not tracked by the government – under fuel economy requirements.

Snowe, a member of the Senate Committee on Commerce, Science and Transportation, and other Commerce Committee members, including Sens. Kerry, McCain, Ernest Hollings, D-S.C., and Gordon Smith, R-Ore., took credit for negotiating the compromise.