"This is a great opportunity for our country to get our groove back after a number of years of challenges," said Dan Poneman, the president and chief executive officer of Centrus Energy Corp, a maker of fuel for advanced nuclear reactors that are expected to become commercial in coming years.

Biden, who takes over on Jan. 20, wants to make curbing climate change one of the pillars of his administration and has supported research and development for advanced nuclear technologies.

Nuclear reactors generate virtually emissions-free power which means they can form a part of getting to net-zero emissions from electricity generation in the fight to tackle global warming.

The United States has about 94 traditional reactors, out of the 440 worldwide, but rising costs have forced many plants to shut with five more expected to close this year in Illinois and New York. Nuclear power faces competition from electricity stations that burn cheap, plentiful natural gas and from renewable power, including wind and solar.

In addition, around the world, nuclear plants face rising maintenance and safety costs, including protection against attacks by militants or regulatory responses to the 2011 Fukushima nuclear disaster in Japan.

Five new nuclear reactors came online last year in China, Russia, Belarus and United Arab Emirates, according to Sama Bilbao y Leon, the director-general of the industry group, the World Nuclear Association.

It is not clear how Biden's administration will prevent more of the current reactors from shutting. Rick Perry, President Donald Trump's former energy secretary, tried to set up subsidies for nuclear power, but the idea was rejected by energy regulators.

In addition, non-proliferation experts have concerns about the supply chains of advanced nuclear, which could involve small plants in more remote locations, and that the waste that they generate could be even more concentrated than spent nuclear fuel from traditional plants.

Still, backers of advanced nuclear energy say their plants will be safer and produce less waste. GE Hitachi Nuclear, a venture between General Electric Co and Hitachi Ltd, hopes to build small advanced power stations called Natrium with TerraPower LLC, a venture founded by Bill Gates, in one example of the next generation of nuclear power.

"It will be all about getting online, getting traction, getting those reactors under construction," Jay Wileman, president and chief executive officer of GE Hitachi told Reuters Next.

Sama Bilbao y Leon said that global policymakers need to structure electricity markets so that the full benefits of nuclear power, including its reliability and emissions-free power are recognized. That way they can compete with renewables and other forms of advanced technology.

"Number one, there is a need for a level playing field in all aspects," for nuclear power, she added.

(Reporting by Nina Chestney in London and Timothy Gardner in Washington, writing by Timothy Gardner; Editing by Nick Zieminski)

By Nina Chestney and Timothy Gardner