Life extension: what decides whether a reactor runs past 40 years

A plant’s age alone does not determine whether it can keep operating. Renewal requires managing the aging of safety-related systems, structures and components, checking their functions and reviewing analyses for the additional operating period. The vessel and containment are part of that assessment, rather than its only determinants. Replacing equipment does not replace the need to demonstrate the safety of the installation.

The NRC attributes the initial 40-year term of US licences to economic and antitrust considerations. It is not a universal physical limit, although some components were designed assuming that service life. The NRC published Part 54 in 1991 and amended it in 1995 to focus on managing adverse aging effects. Renewal also requires an environmental review under Part 51.

US renewals can add 20 years: an initial renewal allows operation to 60 and a subsequent renewal to 80. Turkey Point 3 and 4 received the first subsequent renewed licences on 4 December 2019. The NRC completed-applications table, updated on 8 September 2026, lists 25 units at 13 plants; three other applications remain under review. These are authorisations, not a count of reactors that have already operated for 80 years. In France, authorisation to create an installation has no fixed duration, but continued-operation conditions are reviewed every ten years. Generic decision 2021-DC-0706 for the 900 MWe series is dated 23 February 2021 and was published on 25 February; its requirements are then applied to individual reactors.

The French ten-year inspection includes maintenance and three checks highlighted by EDF: robotic vessel inspection, a primary-circuit hydraulic test above operating pressure, and a containment strength and leak-tightness test. At Paluel 1 these took place in February, May and June 2026, respectively. Their results are essential to restart permission; they do not replace the assessment of long-term continued operation.

The IAEA’s 2020 France profile records Paluel 1 at 1,330 MWe net, with its first grid connection on 22 June 1984. EDF reports an outage from 2 January to 12 September 2026: 253 days between dates, with reconnection at 8:17, the time published by the operator. This was the first fourth ten-year inspection in the French 1300 MWe series; ASNR lists twenty reactors and a schedule through 2034. EDF reports more than 30,000 activities and over 105 modifications. Its announcement distinguishes the permissions obtained to restart from ASNR’s later opinion on operation over the following ten years.

France’s Grand Carénage programme combines safety and maintenance investment to support operation beyond 40 years. On 29 October 2020 EDF revised its 2014-2025 estimate to €49.4 billion in current euros, compared with €48.2 billion in current euros in 2018. The revision incorporated additional safety work and longer expected maintenance outages. This is a dated programme estimate, not a verified final cost or the cost of extending a single unit.