New nuclear reactor designs can now be licensed for 40 years, not 15

US nuclear regulators changed the rules for how long a reactor design certification lasts. These certifications will now be valid for 40 years instead of 15 years. This applies to both existing and future reactor designs.

Building a nuclear power plant takes a long time and costs a lot of money. A 15-year design certification meant that by the time a new reactor was ready to operate, its design approval was already halfway expired. This change gives developers a much longer window to build and operate plants under a single approved design, making the economics more predictable. It removes a major regulatory hurdle for advanced reactor designs that are still in development.