Heard by the National Assembly in January 2023, Cédric Lewandowski, EDF's executive director in charge of nuclear and thermal power plants, lifted the taboo by talking about extending the life of the French nuclear fleet up to 80 years, like some American reactors.

Without going that far, EDF and RTE have been campaigning for several years for extending the life of French reactors by up to 60 years. A first step was taken in 2021. The Nuclear Safety Authority (ASN) gave a favorable opinion to extend the operation of 32 900 MW reactors up to 50 years, subject to safety improvements. On the question of the age of 60, the nuclear policeman invites caution, pending EDF's justifications.

50 years old? 60 years old? 80 years old? Whatever the duration, extending the life of existing power plants is controversial, opposing fervent defenders and detractors of nuclear energy.

What is the current state of affairs of the French nuclear fleet? Why extend its lifespan? What are the benefits and challenges of this perspective? Let's de-escalate the debate.

What is extending the life of a nuclear fleet?

Inventory of the French nuclear park

54%. This is the availability rate of the nuclear fleet in 2022, announced by the electricity transmission system operator RTE in its annual report published in February 2023. This is a record low figure, compared to the 73% average availability observed between 2015 and 2019.

In question? The shutting down of numerous reactors for maintenance operations, technical failures or corrosion problems. At the peak of production, in the summer of 2022, 32 reactors were shut down out of the 56 in the French nuclear fleet.

EDF is now making up for its delay in carrying out maintenance work, delayed by the health crisis. Production resumed gradually this winter. to reach 25.3 TWh in March 2023. But it remains weakened by the aging of the nuclear fleet and the corrosion problems identified in certain reactor safety and cooling systems.

What is the lifespan of a nuclear power plant?

In France, the law does not fix no age limit for nuclear power plants. They were designed for a minimum expected operating period of 40 years.

According to this figure, the 37 reactors commissioned between 1976 and 1985 following the oil shock are reaching the end of their operating life. But technical progress makes it possible to overcome this 40-year barrier. According to EDF,” Today, the great scientific, technical and economic consensus is that our fleet is suitable for reaching 60 years of age ”. This is what the national energy company must now prove.

In the meantime, an initial consensus seems to be emerging with the extension of the lifespan of nuclear power plants by up to 50 years. The agreement was already given in 2021 by ASN for the 900 MW small reactors. Studies are ongoing for the possible extension of the operation of 1,300 MW reactors to 50 years.

Why is it a strategic and economic issue?

Against the background of the war in Ukraine, the year 2022 was marked by an energy crisis, qualified by RTE “unprecedented since the oil shocks of the 1970s”. She highlighted the energy insecurity of European countries, shaken by supply problems and soaring energy prices.

In this unstable environment, France has managed to guarantee the security of its energy supplies and to cushion the rise in electricity costs. The reason? Its nuclear production. Despite a marked decrease in 2022, it represented 63% of total national electricity production.

As stated in the report of the Commission of Inquiry published at the end of March 2023 concerning national energy sovereignty, Nuclear energy Rest the ” pillar of our production and our electrical sovereignty ”.

The benefits of extending the life of a nuclear fleet

Energy independence, control of energy costs, energy decarbonization: the economic and ecological challenges are high. Nuclear power helps to answer them. Faced with the costs and deadlines of building new power plants, extending the lifespan of nuclear power plants offers a pragmatic and secure alternative solution.

Cost reduction

The choice of nuclear power makes it possible to controlling energy costs in France.

In the midst of an energy crisis, the price of electricity in France remains lower than in the rest of Europe. While it exceeds 50 c€/kWh in the United Kingdom, Italy and Belgium — and even 60 c€/kWh in Germany —, The price of electricity tops out at 24.5 c€/kWh in France thanks to the tariff shield. But even without this support from the State, it would remain lower than the price observed in other European countries, at 42.4 c€/kWh.

This French exception is explained by the competitiveness of nuclear production. According to the French Nuclear Energy Society (SFEN), with the extension of the lifespan of nuclear power to 50 years, the cost of nuclear production is estimated at €40/MWh. In comparison, the production of electricity from a gas-fired power plant represents between €90 and €130/MWh.

Reduction in greenhouse gas emissions

Nuclear energy produces a carbon-free electricity. It is an asset for The energy transition in a context of global warming where it is becoming urgent to reduce greenhouse gas emissions.

According to the Environment and Energy Management Agency (ADEME), The nuclear kWh emits 6 g of CO₂, compared to 418 g of CO₂ for gas-fired power plants and 1,058 g of CO₂ for coal-fired power plants. Even renewable energies emit more greenhouse gases, with 10 g of CO₂ for wind power and 30 g for Photovoltaic solar.

Maintaining energy independence

The war in Ukraine and the tensions over electricity and gas supplies have proved it: the European Union is dependent on energy.

In 2020, the average dependency rate in the European Union was 57.5% according to Eurostat statistics. Thanks to nuclear energy, France displayed one of the lowest energy dependence rates in Europe, at 44.4%. In comparison, it was 63.7% in Germany, 68% in the Netherlands and Spain, 68% in the Netherlands and Spain, or 73.4% in Italy.

While the signals are worrying today about France's energy sovereignty, nuclear electricity contributes to its preservation.

The challenges associated with extending the life of the nuclear fleet

Extending the life of the nuclear fleet, however, raises legitimate questions. The challenge ahead? Reassure people about security and costs to promote social acceptance of this energy that inflames debates.

Nuclear safety and security

The images of the dramatic nuclear accidents in Chernobyl and Fukushima remain etched in people's memories. According to the international scale of nuclear events, 16 accidents have occurred since 1959.

Incidents are rare thanks to strengthened regulations on nuclear safety and security. In France, ASN is responsible for this highly responsible mission. This administrative authority controls the safety status of nuclear power plants and approves operating permits.

The agreement to extend the life of 900 MW reactors to 50 years is accompanied by compliance withsecurity obligations In order to “bring the safety of operating reactors to a level close to that of third-generation reactors, such as EPR”.

Safety is at Heart of Grand Carénage program that EDF hired as early as 2014. The work involves the renovation and replacement of components reaching the end of their technical life, the modifications necessary to improve safety and the guarantee of the sustainability of the qualification of equipment after 40 years.

Among the security improvements to be made, ASN has targeted three objectives :

• La “reduction of the consequences of possible accidents involving a fusion at the core of the reactor” (radioactivity confined inside the enclosure),
• The “strengthening in the face of internal and external natural risks” (earthquake, flood, extreme heat, fire,...),
• The “reinforcement at the level of the spent fuel storage pool”.

Costs and financing

Opponents of extending the life of nuclear reactors point to the colossal costs of renovations. They are not wrong. The investment is expensive.

The EDF Grand Carénage project is valued at 50 billion euros until 2025. The extension of the operation of existing power plants to 60 years was estimated at 100 billion euros by the Court of Auditors in 2016.

These amounts should be compared with the costs and time required to build new nuclear power plants. The price of the construction of three pairs of EPR2 (i.e. six reactors) is estimated at 52 billion euros over a period of 25 years. A small SMR modular reactor, which is more flexible and faster to build, should cost between 100 million and 1.5 billion euros, but its power is lower (between 10 and 300 MW).

In comparison, the investment to extend the life of the nuclear fleet is a Shorter-term, less risky and amortizable investment thanks to the low cost of producing nuclear electricity.

Social acceptability

Despite its advantages, nuclear power faces the challenge of social acceptability. Beyond questions of safety and financing of power plants, nuclear energy raises other legitimate debates, including radioactive waste management and the import of uranium.

Today, no energy system offers an ideal solution. None meets all the criteria for social acceptance. The question today is not to oppose Nuclear energy to renewable energies. The strategy is to tend towards a French energy mix, ensuring both energy independence, the control of energy costs and carbon neutrality.

In this context, extending the life of the nuclear fleet can offer a Transitional solution — certainly questionable —, but efficient in the short and medium term, amortisable and a pillar of the energy transition.

Today, renewable energies are a complement to the production of nuclear electricity. The ideal to achieve? Let the curve reverse progressively. This is the challenge of the energy strategy announced in 2022 by President Emmanuel Macron, symbolized by the law on the acceleration of renewable energies of 10 March 2023 and the French nuclear recovery plan.

Do not hesitate to consult our article on: Strengthened nuclear security: the role of the Rapid Nuclear Action Force (FARN)