Technology to capture and store carbon dioxide emissions by coal-burning power plants won’t be widely available until 2045, a Bush administration official told a House panel Tuesday, potentially complicating efforts to pass climate-change legislation.

There is growing momentum in Congress — opposed by the White House — to enact legislation that would restrict emissions of carbon dioxide and other gases blamed for contributing to global warming. Several bills would require significant reductions in carbon dioxide emissions by 2020.

But without cost-effective technology to burn coal cleanly, the goal of cutting greenhouse gas emissions may collide with the president’s objective to make the country more energy independent. The abundant U.S. coal reserves provide about half the nation’s electricity.

“If carbon controls take effect before the capture and storage technologies are available, there could be a rapid switch from coal to other fuels that would be unbearable for our economy,” said Democrat Rick Boucher, who represents Virginia’s sole coal-producing district and chairs the House Energy and Commerce panel with the lead role in writing a climate-control bill. “Fuel-switching away from coal would significantly increase electricity prices to the detriment of residential and industrial electricity consumers.”

Boucher said before the hearing by his Energy and Air Quality Subcommittee that he may try to include language in climate-control legislation that would prevent some requirements from kicking in before industry-friendly technology is available.

Thomas D. Shope, the Energy Department’s principal deputy assistant secretary for fossil energy, said that technology is unlikely to be available at an affordable cost before 2025, under funding levels for research and development recommended by the administration. Doubling the budget requests would speed up the timetable, he said.

By 2025, a power plant using carbon sequestration technology would be about 10 percent more expensive than a standard pulverized-coal plant, Shope testified.

He added that by 2045, the costs would be roughly equivalent.

The administration, which recommended $79 million in fiscal 2008 for the Energy Department’s “clean” coal research and development, has steadfastly opposed any mandatory limits on greenhouse gas emissions, instead touting technological solutions, the use of cleaner alternative fuels and voluntary steps by industry.

But critics of that approach say an emissions cap is needed to spur more private investment in developing clean coal technology and enticing industry to use it.

“No one is going to spend the money to do it [without a cap],” said Jay Inslee, D-Wash. “Why would anyone spend their money if the Bush administration is allowing pollution for free?”

“I like to think that if the technology is there, it will be used,” Shope replied.

David G. Hawkins, director of the Natural Resources Defense Council’s climate center, said coal plants slated to be built in the next 25 years without clean coal technology will emit 30 percent more carbon dioxide in their operating lives “than has been released from all prior use of coal.”

But he conceded that coal will remain an important part of the nation’s energy mix.