Scientists in southern Idaho are at the forefront of efforts that could help make atomic energy an important option to curb the emission of greenhouse gases.
Nuclear power plants emit no such gases, which advocates say makes them a great replacement - along with renewables and other cleaner technologies - for traditional coal-burning plants.
"Nuclear is increasingly very competitive with all other choices," John Grossenbacher, director of the government-funded Idaho National Laboratory, said in terms of cost. "It's very reliable and extremely safe."
Part of the lab's mission is to develop safer nuclear technology, a task growing in importance as the Bush administration touts nuclear as an energy solution at home and abroad. And a recent report from the worldwide Intergovernmental Panel on Climate Change (IPCC) did not rule out the use of nuclear power as part of the mix to combat global warming. A Utah governor's advisory panel on climate change last week also included limited support for developing nuclear power.
But environmentalists remain skeptical. Simply emitting no greenhouse gases doesn't make nuclear an environmental option, they contend. Atomic power has lingering problems, most notably the lack of a permanent repository - anywhere in the world - for long-lived, highly radioactive waste.
"It's really the only selling point they can find to make Americans even consider going that option again," said Vanessa Pierce, head of HEAL Utah, a nonprofit group that monitors nuclear issues, referring to global warming.
If nuclear power is a viable answer to fighting global warming, the question boils down to this: Are Americans ready to see more cooling towers of nuclear power plants cast shadows across the nation's suburbs and farm fields?
By one estimate from the Massachusetts Institute of Technology, at least 1,000 new nuclear plants would be needed worldwide in the next 50 years to make a dent in global warming. Some question whether such a building spree would be possible.
"Nuclear technology is re-emerging as a power generation option in the face of concerns about climate change, energy demand growth and the relative cost of competing technologies," wrote the authors of a recent report by the Keystone Center, a nonprofit science-policy group that brought together nuclear power providers and environmental groups for its assessment. "After more than a decade in which no new nuclear power plants were completed in the U.S., nuclear power is now the focus of considerable attention and debate."
Idaho National Laboratory: The nuclear industry can trace its roots to a small experimental reactor in southern Idaho. The facility, now on Idaho National Laboratory property, briefly powered the nearby town of Arco.
Even if nuclear power does not see a renaissance in the U.S., that does not diminish the role of the research at the Idaho lab. The U.S. wants to maintain a leadership role in nuclear research, even if it benefits other nations first, Grossenbacher said.
For two decades, the lab has been the nation's leading government research facility on nuclear issues, said Dave Hill, deputy director for science and technology at Idaho National Laboratory. The lab has other roles, including finding ways to improve battery life and energy conservation and homeland security - but nuclear ranks among its top priorities.
The campus includes an advanced test reactor, lab facilities where materials can be manipulated inside a sealed room to protect scientists and fuel manufacturing facilities.
Researchers at the sprawling facility are working on next-generation nuclear power plant designs, new ways to more safely reprocess spent nuclear fuel and future uses for nuclear power.
These research efforts help support the proposed Global Nuclear Energy Partnership (GNEP), which looks to expand nuclear's role around the world.
Other research includes devising new ways to make use of nuclear technology.
"We're looking at how to couple nuclear with other resources to produce liquid fuels domestically," said Hill.
Small nuclear reactors could provide the heat needed to extract liquids from oil shale and tar sands, a way to reduce the nation's reliance on foreign fuels.
For the immediate future, nuclear's main role will remain electricity production.
Nuclear power: Good, bad and spent: More than 400 nuclear power plants provide about 17 percent of the world's current energy needs, according to the MIT nuclear study. France is the most reliant nation, with 78 percent of its energy coming from nuclear power.
The United States has 104 operating commercial reactors, which combine to produce 30 percent of the world's nuclear energy. Nuclear provides about 20 percent of the U.S. energy mix.
But no new nuclear plants have been built in the United States in the past 30 years.
Some say the U.S. industry is still reeling from the near meltdown in 1979 at Pennsylvania's Three Mile Island nuclear power plant. Nuclear experts argue that the accident showed safety precautions work, while critics were upset that the accident occurred at all.
Investors also seem to have grown leery because of the high up-front capital costs and lengthy potential delays before a new plant ever comes on line - some plants took more than 20 years to become operational.
The Nuclear Regulatory Commission (NRC) expects about 30 applications for new reactors through 2009, though it's unclear how many of those will be built.
The Bush administration would like to see even more of the world relying on nuclear power. GNEP's broad goals are to increase the number of nuclear power plants around the world and help nations safely create nuclear power programs while preventing others from using fuel byproducts for bombs.
GNEP aims to limit proliferation by creating a system of fuel-producing and fuel-using countries. Nations interested in nuclear power, which may aim to create weapons programs, would be among the fuel-user states. These countries could use nuclear power, but not have fuel-making facilities, which can also be used to create weapons material.
A much-debated piece of GNEP involves reprocessing spent nuclear fuel.
Grossenbacher contends that recycling spent fuel, which is not done in the U.S., will mean less highly radioactive waste destined for a permanent repository. But reprocessing separates out weapons-usable elements, like plutonium, which opponents contend poses too great a risk of weapons proliferation. Reprocessing also costs too much compared to traditional uranium mining, critics contend.
Even if no new nuclear plants are built, there remains the question of where to store deadly waste from reactors. Plans for the nation's first permanent repository of high-level nuclear waste in an underground facility at Yucca Mountain in Nevada remain stalled.
A proposal to use Utah's Skull Valley to temporarily store some of that waste faces a similar battle.
More nuclear power plants could bring an increase in low-level radioactive waste to EnergySolution's Tooele facility.
Spent fuel rods, which account for much of the nation's nuclear waste, remain stored at the commercial nuclear power plants where they were created.
As the waste debate continues, traditional coal-fired power plants are generating more than half of the country's daily electricity. These plants emit carbon dioxide, which is a greenhouse gas that builds in the atmosphere and warms the planet.
If greenhouse gases are not brought under control, the average global temperature could rise as much as 9 degrees by 2100, according to IPCC estimates.
A number of scenarios worldwide include nuclear as one piece in the puzzle to stabilize or reduce energy-related carbon emissions.
Debate over the future: Several environmental groups would prefer to see nuclear deleted from the global warming-solution equation.
"It's a huge P.R. campaign to reinvent nuclear as a green and clean energy source," said Michele Boyd, energy program legislative director of Public Citizen, a nonprofit watchdog group. "None of the problems have been solved."
Even if the Yucca Mountain repository is built, critics say there is already more waste sitting at plants across the nation than would fit into the facility.
Even if the repository question were solved, critics doubt there would be enough resources for the world to embark on the unprecedented scale necessary to build enough nuclear plants to make a difference in defeating global warming.
Plant safety also remains a top concern, at home and abroad.
The non-profit group Union of Concerned Scientists reported safety repairs required nearly 30 U.S. reactors to shut down for at least a year since the 1980s. There have been a number of near-misses the public rarely hears about, said Jon Block, a nuclear expert with the organization.
Changes in the NRC licensing process, he said, have made it more difficult for the public and opposition groups to learn critical details about potential nuclear plants. The watchdog group is also worried the nuclear industry has too much influence over the NRC, the agency designed to monitor the power providers.
Boyd said environmental groups see a bright future in improving energy efficiency and investing more money into renewable resources, like wind, solar and geothermal. She said research is under way to make solar and wind work more like coal and nuclear in terms of reliability, regardless of the weather.
Patrick Moore, who helped found Greenpeace, said he is skeptical renewables will replace coal or nuclear as a primary power source. Moore, who began his career protesting nuclear weapons, is now pushing atomic power as an answer for global warming concerns. "No other technology is offsetting as much carbon emissions today in the U.S. as nuclear energy," said Moore, who is co-chairman of the Clean and Safe Energy Coalition, a nuclear-industry funded organization.
Moore, who heads the consulting firm Greenspirit Strategies, said the nation's repository issue is solved, but politics are preventing Yucca Mountain from opening.
Officials at Idaho National Laboratory acknowledge a role for renewable resources, but they argue that wind and solar are still only intermittent energy providers. "In the end, it's not enough," Grossenbacher said of renewables. "We still need large, concentrated energy production sources."
With the nation's vast coal reserves, that resource must also be part of the mix, Grossenbacher said. To help fight global warming, power companies need to find ways to capture carbon emissions.
Explained Hill, the lab's deputy director for science and technology, "It's going to take some of everything. There's no one solution."