As some nuclear power companies continue to shut down nuclear reactors for reasons ranging from economic woes to safety concerns, Bill Gates is bullish on nuclear power as a clean energy solution to climate change.

Gates, who is also an investor in nuclear power, told the Nuclear Energy Institute’s Nuclear Energy Assembly on Wednesday that the United States needs to strengthen its commitment to existing nuclear power plants and invest in new ones.

“Today, nuclear power is at a crossroads. Nearly 20% of America’s electricity comes from nuclear,” Gates said. “But while America’s current nuclear capacity serves the country well, there are far more reactors slated for retirement than there are new reactors under construction.”

In April, the Indian Point Energy Center nuclear power plant north of New York City retired its last operating nuclear reactor. And the Exelon Corporation has announced plans to retire two of its Illinois nuclear power plants in the fall.

If these retirements come to fruition, 2021 could set a record for the most retirements of nuclear generators in a year, according to the U.S. Energy Information Administration (EIA). Since 1960, the United States has retired 40 nuclear generators but it has never this many in one year, sasy an EIA spokesperson.

According to Gates, “if we’re serious about solving climate change, and quite frankly we have to be, the first thing we should do is keep safe reactors operating.”

But “even then, just maintaining that status quo is not enough. We need more nuclear power to zero out emissions in America and to prevent a climate disaster,” Gates said Wednesday.

(Getting to “net zero” emissions means achieving no new quantity of emissions in the atmosphere, according to the United Nations, both through reduced emissions and removal of emmissions from the atmosphere.)

Gates is the founder and chairman of TerraPower, an advanced nuclear technology company that launched in 2006. On June 2, TerraPower announced it will build an advanced nuclear power plant at a retiring coal power plant in Wyoming. The specific location in Wyoming is not yet decided: several potential locations in Wyoming are under currently under consideration, according to the company.

Gates said Wednesday that TerraPower will use the coal plant’s existing infrastructure and its skilled workforce to build and operate the advanced reactor plant, which is called Natrium. TerraPower developed the Natrium technology in collaboration with GE Hitachi Nuclear Energy.

“We hope to show that on top of all of its energy benefits, advanced nuclear can play a key role in the development of good jobs for skilled workers across the country,” Gates said.

Other companies, like the Rockville, Md.-headquartered X-energy, are also building advanced nuclear reactors.

In October, the U.S. Department of Energy (DOE) announced it is investing $80 million in TerraPower and X-energy, for a total of $160 million. Rita Baranwal, then the Assistant Secretary for nuclear energy, said at the time that the urgent development of nuclear technology is “important not only to our economy, but to our environment….” (Baranwal is now the chief nuclear officer at the Electric Power Research Institute, a global research and development energy organization.)

Though Gates “strongly” believes “nuclear power must play a role in getting the world to net zero,” and that everyone from technologists to utility companies must have “a common vision for the role of nuclear in our electric grid,” other experts disagree.

For instance, in February, academics and other researchers signed a public declaration calling for fighting climate change by transitioning to 100% renewable energy from sources including wind, solar, hydropower, geothermal, tidal and wave energy.

Nuclear energy is not considered renewable, says Stanford University professor Mark Z. Jacobson, one of the signatories of the declaration. Nuclear fission, the process currently used to create usable nuclear energy, requires uranium as a fuel, which is a finite resource, he says.

Jacobson says that, in fact, “investing in new nuclear power is the surest way to climate disaster.” Climate change is urgent, and new nuclear power plants are expensive and take a long time to build, he says.

Jacobson, who has published a textbook on renewable energy, also points out that nuclear power comes with concerns that renewables don’t have, including weapons proliferation, meltdowns, radioactive waste and uranium mining risks.

“New nuclear is basically an opportunity cost,” he says.

See also:

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How Bill Gates’ company TerraPower is building next-generation nuclear power

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