WASHINGTON – The U.S. should adopt a crash program to double automobile fuel efficiency, limit carbon emissions and push as hard as it can for bio-fuels and other energy sources over the next 25 years or risk serious shortages, says a study released Wednesday.

The National Petroleum Council, a government advisory panel with members ranging from oil and gas producers to environmental experts, prepared the report for the Bush administration.

It includes a remarkably pessimistic outlook from a dozen international oil companies, which provided proprietary forecasts that show oil supplies falling short over the next two decades unless there is either a significant slowdown in economic growth or a big move for energy savings.

Among the council's recommendations is a call for the federal government to allow "environmentally responsible development" of currently restricted federal lands such as the Atlantic and Pacific coastal shelves and the coastal plain of the Arctic National Wildlife Refuge in Alaska.

It also advocates a doubling of the fuel economy of new cars and light trucks sold in America, which last fall averaged 22.2 miles per gallon.

The study comes as Congress debates legislation to address energy issues.

"Hopefully, our policymakers will go off and seriously consider this report," said Ray L. Hunt, chief executive of Dallas-based Hunt Oil Co. "If not, then there is the prospect of a market with serious energy distortions."

A bill passed last month in the Senate calls for raising fuel economy standards for new autos and light trucks sold in the U.S. to an average of 35 miles per gallon, a measure that would fall short of the Petroleum Council's recommendation.

In addition, the Senate bill doesn't seek drilling on restricted federal lands.

Jeff Bingaman, D-N.M., chairman of the Senate Energy Committee, praised the report without addressing its recommendations for expanded drilling.

"This report underscores the urgency for America to move faster and go further to secure its energy future. I agree with its conclusion that greater energy efficiency is required throughout all sectors of our economy," he said.

Energy Secretary Samuel Bodman said the administration would give the report "serious consideration." President Bush, in his State of the Union address in January, urged Congress to act on several similar steps, although he showed less enthusiasm than the Petroleum Council for limiting carbon emissions.

Mr. Bodman had asked for the report in October 2005, largely to answer concerns that world oil production will soon peak, leading to supply shortfalls in the future.

National Petroleum Council chairman Lee Raymond, a former chairman and chief executive of Exxon Mobil Corp., recruited a panel of 350 oil and gas producers, energy-consuming industries, automakers, academics, consultants and environmental experts who spent more than a year analyzing forecasts and technical data.

Two-thirds of the experts who helped draft the report came from outside the oil and gas industry.

While chairman of Exxon Mobil, Mr. Raymond was an outspoken critic of efforts to curb carbon emissions as a way to combat global warming.

But Wednesday's report urges the federal government to work with China and other nations to curb such emissions, enact rules for burying carbon gases deep underground and establish a cost for carbon-related pollution – either through a tax applicable to all carbon dioxide emitters or through an emissions-trading system.

While experts advocating a "peak oil" perspective dwell largely on how much oil can be recovered from the world's reservoirs, the Petroleum Council's report concludes that "the world is not running out of energy resources."

But, it said, there are growing risks to the world's ability to continue the expansion of oil and natural gas production. Although the report shies away from the gloomy forecasts of the peak oil advocates, it concurs with their recommendations for speeding the development of alternative fuels and conservation.

Proprietary forecasts from the international oil companies concluded there will be 107 million barrels a day of supply by 2030. But that's 10 million barrels a day less than the global demand forecast by the U.S. Energy Information Administration – an amount equal to total U.S. gasoline consumption currently.

To bring demand into balance with the forecast supply, world economic growth would have to slow to 1 percent a year – unless conservation efforts can chip away at usage. For example, the report said U.S. oil consumption could fall between 3 million and 5 million barrels a day if automobile and light-truck fuel efficiency doubles in the next 23 years.

The report also urges development of bio-fuels made from grasses and agricultural wastes to the tune of 4 million barrels a day by 2030.

Advocates of the peak oil theory criticized the report.

"The NPC artfully camouflages the enormous near-term challenges in producing sufficient oil and gas to fuel the global economy," said Randy Udall, a board member of the Association for the Study of Peak Oil and Gas, a think tank based Denver. "Hard truths are hinted at but are never clearly identified. Troubling trends are referenced, but their ramifications are dodged."

The report's emphasis on energy efficiency included recommendations for tougher energy consumption standards for appliances, homes and commercial buildings.

It points out that many of the efficiencies gained in the last three decades were effectively canceled by consumer demands for larger homes, more appliances such as a second refrigerator, and bigger, more powerful cars.

Americans have been reluctant to invest in energy conservation unless the costs can be recovered through lower energy bills within two years.

The report estimates adoption of energy-efficiency measures with 10 percent or better rates of return could cut residential energy demand in the U.S. by 36 percent.

Looking at electricity alone, Texas homeowners could curb their consumption by 32 percent, the study found.

Dan Yergin, author of an oil industry history called The Prize and president of the industry consulting firm Cambridge Energy Research Associates, predicted other nations, such as China, would compare their own potential to save energy against the report's findings.

"It's the most comprehensive energy study that I've ever seen," Mr. Yergin said.

The 422-page document, "Facing the Hard Truths About Energy," is posted on the council's Web site at www.npc.org.