WASHINGTON — Congress by a wide margin approved the first increase in automobile fuel economy in 32 years today, and President Bush plans to quickly sign the legislation, accepting the mandates on the auto industry.

The energy bill, boosting mileage by 40% to 35 miles a gallon, passed the House 314-100 and now goes to the White House, following the Senate’s approved last week.

In a statement, the White House said Mr. Bush will sign the legislation at the Energy Department tomorrow.

In a dramatic shift to spur increased demand for nonfossil fuels, the bill also requires a six-fold increase in ethanol use to 36 billion gallons a year by 2022, a boon to farmers. And it requires new energy efficiency standards for an array of appliances, lighting, and commercial and government buildings.

“This is a choice between yesterday and tomorrow” on energy policy, declared Speaker Pelosi, Democrat of California, who was closely involved in crafting the legislation. “It’s groundbreaking in what it will do.”

While some GOP lawmakers criticized the bill for failing to address the need for more domestic oil and natural gas production, 95 GOP lawmakers joined Democrats in support of the bill.

“This legislation is a historic turning point in energy policy” because it will cut demand for foreign oil and promote nonfossil fuels that will cut greenhouse gases linked to global warming, the majority leader, Rep. Steny Hoyer, said.

It increases energy efficiency “from light bulbs to light trucks,” a longtime protector of the auto industry who was key to a compromise on vehicle efficiency increases, Rep. John Dingell, Democrat of Michigan, said.

Many Republicans denounced the Democratic-crafted bill for failing to push for more domestic production of fossil fuels and for mandates some GOP lawmakers warned will not be possible.

“What we have here is a mandatory conservation bill,” Rep. Joe Barton, Republican of Texas, said. He argued that the auto fuel efficiency requirements and the huge increase in ethanol use may not prove to be technologically or economically possible.

Democrats disagreed. The legislation takes measured and concrete steps that are achievable, Mr. Dingell said.

The Senate passed the bill last week after discarding billions of dollars in higher taxes on oil companies and a solar and wind power mandate that opponents said would raise electric rates in the Southeast. President Bush and Senate Republicans opposed those measures.

The centerpiece of the bill remained the requirement for automakers to increase their industrywide vehicle fuel efficiency by 40% to an industry average of 35 mpg by 2020 compared to today’s 25 mpg when including passenger cars as well as SUVs and small trucks.

Congress has not changed the auto mileage requirement since it was first enacted in 1975.

Democrats said the fuel economy requirements eventually — when the fleet of gas-miser vehicles are widely on the road — will save motorists between $700 and $1,000 a year in fuel costs. They maintain the overall bill, including more ethanol use and various efficiency requirements and incentives, will reduce Americanoil demand by 4 million barrels a day by 2030, more than twice the daily imports from the volatile Persian Gulf.

The automakers have repeatedly fought an increase in the federal fuel standard, known as CAFE, maintaining it would limit the range of vehicles consumers will have available in showrooms and threaten auto industry jobs. Mr. Bush also has argued against an arbitrary, numerical increase in the fuel efficiency requirement, preferring instead legislation to streamline the federal requirements and market incentives to get rid of gas guzzling vehicles.

But the automakers have accepted the political shift toward a tougher requirement. After the Senate approved the legislation last week, the White House immediately said Mr. Bush would sign it once it reaches his desk.

“While the president’s alternative fuel standard and CAFE proposal would have gone farther and faster, we are pleased that Congress has worked together on a bipartisan way that provides the chance for the president to sign a bill that does not include tax increases.” a White House spokeswoman, Dana Perino, said.