It makes little sense for fully functional and existing nuclear plants to not be running though because politics/cheap gas/lobbying.

About 90 terawatt hours (TWh) of nuclear generation is scheduled to retire in the next decade, more than all of the US’s current solar generation. Studies suggest that another 135TWh is probably not cost competitive with gas plants and, therefore, at risk of retirement.

This means the source of about 15% of US low-carbon electricity could shut down and largely be replaced by gas, making it harder for the US to meet its emission reduction targets.

Research suggests that many existing nuclear plants would avoid being shut down if they were rewarded for their minimal CO2 emissions. Additionally, keeping existing nuclear plants open may be one of the lowest-cost forms of carbon mitigation, cheaper than building new wind or solar plants to replace them.

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