WASHINGTON — Spurred by a demand for cleaner energy and buoyed by a receptive Congress, a nuclear power renaissance appears looming on the horizon.

Nearly three decades after the Chernobyl disaster and the Three Mile Island scare, nuclear energy is on the rebound, promoted as the most viable path to reduce greenhouse gas emissions and produce cheap, reliable electricity.

Tennessee and Georgia lawmakers, who are strong proponents of nuclear power, are central to the industry’s lobbying efforts on Capitol Hill. The Southeast leads the nation in population growth and electricity demands are on the rise, making the region fertile ground for nuclear expansion.

“Nuclear should be part of the solution,” said Rep. Zach Wamp, R-Tenn. “You have to bring on new capacity, and nuclear does that quicker than any other electricity-producing measure. We need a nuclear renaissance.”

The Associated Press -- The unfinished Bellefonte Nuclear Plant, photographed in 2006, is in Hollywood, Ala.

However bright nuclear energy’s prospects appear, environmental groups, such as the Sierra Club and Greenpeace, remain steadfastly opposed to the industry’s expansion. Several key lawmakers, including Rep. Ed Markey, D-Mass., chairman of the House Select Committee on Energy Independence and Global Warming, also are skeptical.

“This industry ... keeps holding its hands out for subsidies from the taxpayer that would be better spent on new, clean alternative energy sources,” Rep. Markey said at a 2007 news conference.

Congress approved more than $970 million in new funding for nuclear power programs last year. With each new nuclear plant expected to cost at least $4 billion, the industry lobbies aggressively for government dollars as a way to attract more private investors.

As the nuclear issue evolves in Washington, lobbyists for the industry grew from 429 in 1998 to 951 last year, according to the Center for Responsive Politics.

SOUTHEAST AT FOREFRONT

The Senate expects to consider a climate change bill with an emissions cap-and-trade system that could be the nuclear industry’s best opportunity to increase its footprint.

The proposed bill mandates a cut in greenhouse gas emissions by 70 percent by 2050 but does not specify for utilities which low-emissions sources to adopt.

Cap-and-trade systems place limits on the amount of greenhouse gas emissions a utility can produce. Companies that are compliant can sell their remaining allowances on the open market to those that exceed the limits.

Sen. Johnny Isakson, R-Ga., a member of the Environment and Public Works Committee, where the bill originated, has so far been unsuccessful in attaching nuclear to the eligible sources to meet clean-air mandates.

“It’s good for the environment, and it’s good for the consumer,” Sen. Isakson said. “The utilities supporting cap-and-trade are the ones in nuclear because they’re already compliant. They want to sell their credits to the coal utilities.”

The current 104 nuclear plants provide 20 percent of the nation’s power. France, by comparison, generates 80 percent of its electricity from nuclear sources.

To keep pace with growing energy demand, studies estimate 45 to 50 nuclear plants must be built in the U.S. by 2050.

No U.S. utility has built a nuclear reactor in more than 30 years, and the last commercial nuclear reactor built and licensed was Unit 1 at TVA’s Watts Bar Nuclear Plant near Spring City, Tenn., in 1996.

Loan guarantees in the 2005 energy bill sparked increased interest in building reactors. The Nuclear Regulatory Commission expects to receive 15 nuclear power plant applications in 2008.

Plants could gain tax credits of up to $125 million for eight years and loan guarantees for up to 80 percent of the building costs. The first new reactor could come online by 2018.

The Tennessee Valley Authority submitted one of the first applications in a streamlined permitting process. In conjunction with a utility consortium known as NuStart Energy LLC, TVA filed an application for a combined operating license to build two next-generation reactors at its Bellefonte site in Hollywood, Ala.

TVA stopped construction in 1988 on two reactors planned at Bellefonte after delays and cost overruns. But the new General Electric AP-1000 reactors are expected to be built quicker and for less money.

“Nuclear is a zero carbon producer. It is the type of power production we need to embrace for electricity,” said Sen. Bob Corker, R-Tenn., a member of the Senate Energy Committee.

Though the industry has found most of its congressional friends among the Republican ranks, nuclear energy also has the support of many Southeast Democrats.

“We’ve reached the point now where we need to take another look at nuclear,” said Rep. Lincoln Davis, D-Tenn.

CRITICISM ABOUNDS

Skeptics criticize nuclear technology as too expensive and unsafe.

Jim Riccio, a nuclear policy analyst with Greenpeace which has fought the nuclear industry for two decades, said utilities have yet to prove that nuclear energy can be cost-effective without major government subsidies and loan guarantees. He said the nuclear industry has understated the cost of constructing new plants, which often face massive budget overruns.

With the first new reactor coming online in 2018 at the earliest, Mr. Riccio said painting nuclear energy as a panacea for emissions control and global warming is disingenuous. Greenpeace favors a greater focus on efficiency measures in combating global warming.

“If we continue to throw good money after bad technology and subsidize reactors that are uneconomical, you’re not going to address climate change,” Mr. Riccio said.

Other opponents cite safety and security concerns, stating nuclear plants could become targets for terrorist organizations. Disposal of spent fuel also is an issue, with a long-proposed nuclear waste storage facility at Yucca Mountain in Nevada stymied by opposition, including Senate Majority Leader Harry Reid, D-Nev.

The Union of Concerned Scientists recently criticized the Nuclear Regulatory Commission for not enforcing and implementing stringent security guidelines.

“An expansion of nuclear power could ... worsen the threats to human safety and security from radioactive releases and wider access to materials that can be used to make nuclear weapons,” the group recently wrote in a report. The UCS is a nonprofit advocacy group that examines government policies.

But some environmentalists previously opposed to the expansion of nuclear power view it as a more palatable alternative to cheap but pollutant-laden coal, which generates most of the electricity in the United States.

“Given the scope of the climate problem and the emissions problem, we need to look at all the energy options we have, and nuclear is one of them,” said Tony Kreindler, spokesman for the Environmental Defense Fund. EDF is a nonprofit environmental advocacy group.

FUTURE OUTLOOK

A report by Cambridge Energy Research Associates, a leading adviser to energy companies, showed positive political, environmental and economic trends for nuclear energy prospects for expansion over the coming decades.

“Over the past few years, high fossil fuel prices, energy security and climate change concerns and increasing urgency about reducing greenhouse gas emissions have all converged to improve the position of nuclear power relative to other options,” the report states.

Derrick Freeman, a lobbyist with the Nuclear Energy Institute, said he senses a much greater acceptance of nuclear power in Congress over the past few years.

“There’s bipartisan spirit that’s taking place with nuclear power,” he said. “In Congress, there’s a thirst for knowledge about energy issues across the board.”

Tennessee and Georgia lawmakers say they plan to keep up the fight, with the nuclear industry vital to the Southeast’s growing energy demands.

Sen. Lamar Alexander, R-Tenn., noted that during debate over the 2005 energy bill, not a single anti-nuclear amendment was offered.

“That’s a big change from years ago,” he said. “People are simply facing the facts. If you really want to deal with global warming, the only technologies available in this generation are conservation and nuclear power.”

BY THE NUMBERS

* 104: Number of nuclear reactors in the country

* 20 percent: Portion of electricity generated by nuclear in the United States

* 0: Amount of carbon emissions generated by nuclear power

* 807 billion: Kilowatt hours of electricity generated by nuclear in 2007, a record high

* 31: Number of countries using nuclear power

* 0: Number of new nuclear plants built since Three Mile Island scare in 1979