"There will be carbon regulation of some sort," said Dan Arvizu, director of the National Renewable Energy Lab of the Department of Energy, told an international conference on biofuels.
He spoke a week after briefing President Bush's global warming conference of major carbon-emitting nations.
"I am neutral as to which kind of carbon management regulation there will be. It is very clear to me that there will be carbon management, whether it will be a direct tax, carbon cap-and-trade or some other instrument," Arvizu said.
Arvizu did not say he was speaking for the Bush administration. But some of his listeners thought it was significant that he spoke after the Washington meeting, which brought together the United States, leading industrial nations that have embraced stringent mandatory controls, and developing countries that are totally unregulated, including China.
"He's picking up the vibe" in Washington, said Patrick Mazza, chairman of the biofuel conference and research director of Climate Solutions based in Seattle.
Arvizu later told The Associated Press the United States "is headed in a different direction than we were a few years ago." He said executives of utility companies and U.S. oil giants — two lobbies that had resisted regulation — now want predictable and transparent carbon policies.
"Certainly my reference point has changed dramatically," he said. "The position of this administration is beginning to evolve."
In his speech to the Washington conference, Bush reiterated his view that each nation should set targets for itself and decide how it will combat global warming without hindering economic growth.
But Arvizu said that, while Bush remained in favor of voluntary targets, his position is not as rigid as it once was, and he made a point of telling the Washington meeting that he has accepted a mandatory renewable fuel standard for vehicles.
He said the U.S. government would invest $2 billion over the next four to five years to develop alternative transportation fuels and reduce dependency on oil imports. The focus on ethanol will shift to a "more robust biofuel," he told industrial leaders and environmentalists who are working on new biofuel solutions.
Transportation accounts for 30 percent of U.S. carbon emissions, he said, compared with a global average of 20 percent.