WASHINGTON - President Bush asked Congress to help solve "one of the great challenges facing our generation" by approving proposals he says will cut U.S. gasoline consumption by up to 20 percent over 10 years.

"Every member of Congress who cares about strengthening our economy, protecting our national security and confronting climate change should support the energy initiatives I have set out," the president said Saturday in his weekly radio address. "We can leave behind a cleaner and better world for our children and grandchildren."

Bush's energy proposals, made in his State of the Union address last month, include ramping up the production of alternative fuels such as ethanol made from new, non-corn feedstocks. The president wants to require the use of 35 billion gallons a year of ethanol and other alternative fuels, such as soybean-based biodiesel, by 2017, a fivefold increase over current requirements. The ethanol would be in gasoline blends of 10 percent to 85 percent.

The call for sharp increases in ethanol use will get bipartisan support in Congress. But production of ethanol from corn is expected to fall far short of meeting such an increase. So Bush envisions a major speedup of research into production of "cellulosic" ethanol made from wood chips, switchgrass and other feedstocks.

The other key element of his plan is changing the way fuel-economy standards are set for passenger cars.

The president wants Congress to give his administration the power to set the standards for cars, using a system it says cuts emissions while preserving choices and safety for costumers. Bush opposes any legislation simply setting a number for higher fuel-economy standards, an approach Democrats like better.

The Democratic-controlled Congress has not entirely dismissed his energy ideas. Still, Bush has unsuccessfully asked for the fuel-economy authority before. And some environmentalists say Bush's goals fall far short of what is needed.

Sen. Jeff Bingaman, D-N.M., chairman of the Senate Energy and Natural Resources Committee, says Bush is ignoring the problem of global warming by not embracing some mandatory emission reductions. The president has made it clear he has no plans to shift away from a largely voluntary program to address climate change, continuing to oppose mandatory reductions of so-called "greenhouse" gases.

"The need for action is clear," Bush said. "Republicans and Democrats both recognize these problems. We agree on the solution: We need to diversify our energy supply and make America less dependent on foreign oil."