Power companies that ignore the coming rules are likely to be on the losing end of the requirements, the executives said at a Houston energy conference.

"I think if our point of view is it's not going to happen then we'll be on the menu and not at the table," said James Rogers, chairman and chief executive of Cinergy Corp

"I think there is only a 25 percent chance carbon will be regulated by '09," Roger said. "I think it is inevitable it will be regulated."

The executives said carbon sequestration will likely be a centerpiece of future legislation with taxes and a pollution credit trading system.

"All of forms of power generation create carbon," said Walter Higgins, chairman, president and chief executive of Sierra Pacific Resources. "Some sort of carbon sequestration is the most likely intermediate-term carbon solution."

Carbon gases are said to be sequestered when they are pumped deep into underground reservoirs.

Power companies are currently planning to build coal-fired plants generating 100 gigawatts of power within the next 20 years, said Alex Urquhart, president and chief executive of GE Energy Financial Services.

"The gas price trend line is up," Urquhart said. "Coal is not that way. Coal will be a big part of the future."

Higgins said Sierra Pacific is planning coal-fired plants to take advantage of the fuel's appeal but will use the technology required to meet expected environmental standards.

Some companies, however, may turn to natural gas plants because they are quicker to build and have less carbon emissions. Relying on gas plants would push natural gas prices higher, Rogers said.

Nuclear power plants, however, do not create carbon pollution, but produce radioactive waste. Even in Nevada, where residents are outraged over US government plans to create a radioactive waste storage site, consumers ask why more nuclear plants aren't being built, Higgins said.