WASHINGTON — President Bush, under pressure to do something about high energy prices, called yesterday for new efforts to harness the "transformational power of technology" to wean the United States from its dependence on oil and gas.

In his second major energy-policy address in a week, Bush proposed several initiatives that he said would help address long-term problems contributing to price spikes and constraining energy production.

They include government-provided risk insurance for new nuclear power plants, expanded federal authority to approve liquefied natural gas terminals, possible construction of oil refineries on closed military bases and a new tax break for people who buy diesel-powered cars.

But for the most part, the president expressed a belief in the ability of the private sector to expand energy supplies and promote conservation through innovation, with modest government involvement to get things rolling.

"In the years ahead, technology will allow us to create entirely new sources of energy in ways earlier generations could never dream," Bush said at a Washington conference sponsored by the Small Business Administration. "Technology ... is this nation's ticket to greater energy independence."

Bush's remarks appear to reflect a delicate balancing act, analysts said. The president, whose aides blame high oil and gasoline prices for his sagging poll numbers, knows he must ratchet up his rhetoric to convince Americans that he, too, feels the sting of high prices. But as a former oilman and business executive, he is hesitant to embrace solutions that involve extensive federal intervention in the energy sector.

"He's trying to convey to the public a sense that he's on the job, that he's concerned about high prices ... and that he's trying to find a way to get more energy to the country as quickly as possible," said Stuart Rothenberg, an independent political analyst in Washington.

Bush acknowledged that none of his proposals would have much immediate effect on prices at the gas pump. But he said they would help lead the way toward a more diversified energy supply and reduced U.S. reliance on foreign crude oil.

Bush said he wants "to reduce uncertainty in the nuclear plant licensing process, and also provide federal risk insurance that will protect those building the first four new nuclear plants against delays that are beyond their control."

After pointing out that no new oil refineries have been built in the United States since 1976, Bush said he "will direct federal agencies to work with states to encourage the building of new refineries — on closed military facilities, for example — and to simplify the permitting process for such construction."