Domestic energy policy has largely been co-opted by the shale revolution. Meanwhile, renewable alternatives are finding their sea legs in consumer power. Despite modest attempts to garner broader acceptance, however, atomic power continues to languish because of safety and environmental concerns.
On Tuesday, the Nuclear Regulatory Commission approved a plan that allows nuclear waste to be stored on-site at active reactors—a decision mired in controversy, and one that underscores the influence of anti-nuclear arguments.
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That sort of opposition has prompted the nuclear industry to go on the offensive, and roll out the big guns in an effort to rehabilitate its image. In recent months, the Nuclear Energy Institute has enlisted organized labor, as well as an array of former elected officials from both sides of the aisle, to tout the virtues of nuclear power.
They insist that in spite of surging oil and gas production, policymakers and utilities shouldn't "put all their eggs in one basket," Judd Gregg, a former U.S. senator and co-chair of Nuclear Matters, said in an interview with CNBC.
"Unfortunately we're confronting a situation where 20-30 plants are at risk of being shut down prematurely," out of the existing total of about 100, the New Hampshire Republican said, who sat on the Senate's Energy Committee during his tenure. "This is really a failure of policy, because it takes out of operation a significant amount of energy production. Nuclear has a lot of positive contributions to offer on a number of different levels."
Fuel diversity, a catchphrase among those who argue that U.S. energy supply shouldn't be dominated solely by oil and gas, is a central theme for nuclear backers. Blanche Lincoln, a former Arkansas Democratic senator and and a member of the Nuclear Matters leadership council, credited nuclear plants with helping keep New England online during the polar vortex last winter.
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"Without nuclear in New England, this year there would have been a lot of trouble," Lincoln said in an interview. Because of a lack of pipeline infrastructure, "getting natural gas into those areas at a time when they really need it" is problematic, she added.
Nuclear power's boosters say that despite high plant investment costs, the fuel source is more eco-friendly than natural gas and even some renewable sources.
A Brookings Institution study published in May said nuclear plants have "far more capacity" to generate electricity than wind, solar or hydro power, but added that decommissioning atomic reactors and disposing of spent fuel "can be very costly."
Meanwhile, international demand for atomic power is growing despite domestic stagnation. In the same breath as they mention clean energy, international policymakers now endorse nuclear power with more frequency. Earlier this month, the International Energy Agency called for India to expand its nuclear capacity in order to cut coal use and provide power to more than 300 million people.
"Energy is at the core of an economy's ability to compete," said Nuclear Matters' Gregg. "We would be foolish to shut down one of our core energy sources."
Too little, too late, say prominent conservationists like the National Resources Defense Council and the Sierra Club. In spite of centrist think tanks like the Third Way who believe nuclear must be part of the energy story, the environmental lobby is steadfastly opposed to expanding existing capacity.
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"We continue to believe nuclear power is not safe, and is an incredibly expensive source of electricity," said John Coequyt, director of the international climate campaign at the Sierra Club. In an interview, he argued that efforts to expand the U.S' nuclear footprint "will take way too long to be a solution to climate change."
Lingering memories of Japan's harrowing disaster in Fukushima, as well as what Coequyt called a few "near misses" here in the U.S., "pretty much killed the willingness of the core of the environmental movement to consider [nuclear expansion] as a solid political strategy."
Many nuclear plant opponents cite cost constraints as a real barrier to expansion. They may have a point: Xcel Energy is facing the ire of regulators after a five-year rebuilding project of a Minnesota plant saw its price tag balloon to $665 million, double its initial estimate.
"Nuclear reactors become incredibly unprofitable and have to shut down when they have problems they need to address," said Coequyt. "Even leaving aside the cost, you don't have the ability to scale like wind and solar, and both are moving incredibly quickly," he added.
—By CNBC's Javier David