How might we uprate and extend existing nuclear assets so that we can unlock gigawatts of clean power faster and cheaper than building new plants?

The fastest path to adding clean baseload power may not be building new nuclear plants — it may be maximizing the ones we already have. The U.S. operates 93 nuclear reactors with a combined capacity of about 95 GW. Many of these plants were originally licensed for 40 years but have been granted 20-year extensions. Some are now pursuing second license renewals to operate for 80 years total. Beyond life extension, many existing reactors can be 'uprated' to produce more power than their original design, typically by improving cooling systems, upgrading instrumentation, or optimizing fuel cycles.

This approach offers compelling advantages: the plants already exist, they're already connected to the grid, they already have trained operators and security in place, and they already have community acceptance (or at least familiarity). The capital cost of uprating is typically $1,000-2,000 per kilowatt — a fraction of the $6,000-10,000 per kilowatt for new nuclear construction. And the timeline is measured in years, not decades. If we can systematically uprate and extend existing nuclear assets, we could unlock 10-20 GW of additional clean power this decade, buying time for next-generation technologies to mature while avoiding premature retirements of proven carbon-free generation.

America's existing nuclear fleet represents one of the largest concentrations of carbon-free baseload power in the world. These plants were built primarily between 1970 and 1990, during a construction boom that made the U.S. the global leader in nuclear energy. At their peak in 2012, U.S. nuclear plants generated over 800 TWh annually — about 20% of the nation's electricity. But the fleet is aging, and until recently, the trend was toward early retirement rather than life extension.

Between 2013 and 2021, 13 U.S. reactors shut down permanently, not because they were unsafe or worn out, but because they couldn't compete economically with cheap natural gas and renewable energy. These closures removed over 11 GW of carbon-free capacity — power that was largely replaced by fossil fuels, resulting in measurable increases in CO2 emissions in affected regions. The closures also eliminated thousands of high-paying jobs and reduced property tax revenues that many communities depended on. It became clear that losing nuclear plants wasn't just an energy problem — it was an economic and climate problem.

The industry began fighting back through two strategies: life extension and power uprating. Life extension involves demonstrating to the Nuclear Regulatory Commission that aging components can be managed safely for additional decades beyond the original license period. Over 90% of U.S. reactors have now received 20-year license extensions, and several have applied for second renewals to operate for 80 years total. This is backed by decades of research showing that nuclear plants, if properly maintained, can operate safely far longer than originally planned.

Power uprating — increasing a plant's output beyond its original licensed capacity — has added over 7 GW to the U.S. nuclear fleet since the 1990s. Uprates typically come in three categories: measurement uncertainty recapture (improving how accurately we measure power output), stretch uprates (small efficiency improvements up to 7%), and extended uprates (major modifications enabling 15-20% more power). The most successful uprates have been at boiling water reactors, where improved cooling and steam systems can significantly boost output. But uprating potential varies by plant design, age, and local conditions, and not every plant is a good candidate.

The economics have shifted dramatically. Rising electricity demand from AI and manufacturing, higher natural gas prices, and new federal incentives for clean energy have improved nuclear plant economics. Several reactors slated for retirement have been saved by state-level support programs that recognize their clean energy value. And the 2022 Inflation Reduction Act created production tax credits for existing nuclear plants, providing up to $15 per MWh for power generation. This has created a new opportunity: rather than just preventing retirements, we can actively invest in maximizing output from the existing fleet through systematic uprating programs.