Nuclear Power: Navigating France’s Post-ARENH Market Transformation

Context: end of the ARENH mechanism on 31 December 2025

As France retired the ARENH (“Accès Régulé à l’Électricité Nucléaire Historique”) scheme on 31 December 2025, the electricity market entered a new regulatory framework from 1 January 2026 built around the Versement Nucléaire Universel (VNU or Universal Nuclear Payment) and the Contrats d’Allocation de Production Nucléaire (CAPN or Nuclear Production Allocation Contracts).

This article examines the shape of the new regulatory environment for nuclear electricity generation and its strategic implications for industrial off-takers, energy producers and investors.

Origins and Objectives of the ARENH Mechanism

Introduced in 2011, ARENH allowed alternative electricity suppliers to buy up to 100 TWh/year of EDF’s nuclear output at a regulated price of €42/MWh, with the main goal of ensuring fair competition in electricity supply and stable prices for end-users.

Over time, structural flaws undermined the mechanism:

• Volume cap: demand consistently exceeded the allocated quota after 2019, resulting in pro-rata allocations that limited the volumes of low-cost nuclear electricity available to  alternative suppliers.
• Below-cost regulated price: the €42/MWh tariff, well under EDF’s production costs and wholesale market levels, created persistent financial pressure.

These shortcomings led to financial losses for EDF—particularly as major investments such as new EPR reactors (estimated at €70 billion) were needed—and market distortions, allowing alternative suppliers to arbitrate low-cost volumes without contributing to long-term generation investments. ARENH also failed to foster genuine asset-backed strategies, highlighting the need for a more sustainable market design.

The “post-ARENH” regime: a two-pillar framework

Article 17 of France’s 2025 Finance Bill, published in February 2025, provides the framework for the “post-ARENH” scheme, known as the VNU (Versement Nucléaire Universel, or Universal Nuclear Payment), built on two complementary pillars: a progressive levy on nuclear electricity revenues and the redistribution of the collected funds to final consumers.

I. Versement Nucléaire Universel (VNU)

The VNU introduces a progressive levy on EDF’s nuclear electricity revenues and redistributes the proceeds to final consumers. 50% of additional revenues generated by historic nuclear power plants are taxed beyond a first threshold, and 90% beyond a second “capping” threshold. These thresholds are determined by the regulator to strike a balance between EDF’s long-term investment needs and benefits for consumers. They are defined as the product of the annual nuclear electricity production by the respective taxation or capping rates:

• Taxation at 50 % of nuclear electricity revenue exceeding full nuclear production costs + [€5–25/MWh]
• Taxation at 90 % of nuclear electricity revenue exceeding full nuclear production costs + [€35–55/MWh]

This upside-sharing mechanism is calculated by the French Energy Regulatory Commission (CRE) and applied as a “tarif unitaire de minoration,” a deduction applied directly to electricity bills, with detailed modalities to be set by regulatory text. Below these thresholds, no automatic compensation applies: if market prices fall below the full cost of nuclear generation, the resulting shortfall remains a market risk borne by energy producers, principally EDF. The mechanism therefore shields consumers from price spikes while leaving low-price exposure with the operators.

On 22 September 2025, following an in-depth analysis of the data provided by EDF, the CRE set the full cost of nuclear power at €₂₀₂₆60.3/MWh (or €61.5/MWh in current euros) for the 2026-2028 period and at €₂₀₂₆63.4/MWh for the 2029-2031 period (or €68.4/MWh in current euros). It also estimated EDF’s 2026 nuclear revenues at €23.8bn for around 360 TWh, i.e. €66.08/MWh – c.€5.8/MWh above the full cost estimate.

On 2 December 2025, the CRE then published an opinion on the draft ministerial order which set the taxation and capping thresholds of the VNU at €78/MWh for the first taxation threshold and €110/MWh for the second capping threshold.

As the VNU levy can only be applied beyond said thresholds, the CRE considers it unlikely that the mechanism will be triggered in 2026 under current market conditions. This assessment was explicitly reiterated by CRE President Emmanuelle Wargon, who noted that wholesale electricity prices have been trading around – or at times below – the €60/MWh benchmark underlying the full-cost calculation.

The CRE will continue to update its estimates of EDF’s nuclear revenues periodically in order to determine whether the mechanism should be triggered.

CRE – Estimated full cost of nuclear power (in €₂₀₂₆/MWh)

CRE – Taxation thresholds based on estimated full cost of nuclear power, regulatory thresholds and market prices (€/MWh)

II. Contrats d’Allocation de Production Nucléaire (CAPN) & ad-hoc contracts

Complementing the VNU, the CAPN are 7- to 15-year contracts designed to offer energy-intensive industries stable, predictable electricity prices closely aligned with nuclear generation costs. Initially targeted at energy-intensive industries, the scheme has since been broadened by EDF to include final consumers with annual consumption above 7 GWh, licensed electricity suppliers and electricity producers. EDF will make 1,800 MW of capacity available under these contracts (around 10.6 TWh/year), with deliveries starting on 1 January 2027. For EDF and other potential energy producers, these agreements secure long-term partnerships with industrial clients who, in exchange for price visibility, commit to sharing part of the fixed and variable costs of nuclear production.

Additional ad-hoc contracts have been signed with highly electro-intensive industrial customers (including Aluminum Dunkerque, Arkema, and Kem One). These contracts incorporate balanced mechanisms for risk and benefit sharing.

Key challenges for the stakeholders

The end of the ARENH mechanism marks a clear shift in France’s nuclear electricity policy. While ARENH helped introduce competition and protect consumers from price increases, its main limitations — a fixed volume and a price too low to be financially viable for EDF — created financial and market imbalances. The new framework, based on the VNU and CAPN, aims to address these issues. It allows EDF to sell electricity at market prices, returns excess revenues to consumers when prices surge, and offers long-term contracts to industrial clients. For investors, the new rules bring greater clarity and stability, making nuclear infrastructure in France more attractive over the long run.

Eight Advisory has identified key challenges for stakeholders:

• EDF will regain control over the pricing of its nuclear output, which could improve its revenues in the medium term. However, this also increases pressure to deliver competitive, reliable, and transparent pricing structures, while managing regulatory scrutiny and formalizing long-term power purchase agreements (PPAs). Additionally, EDF could still struggle with financing much needed investments in nuclear production under those conditions, as the VNU will result in a de facto price control, and EDF considers the cost base set by the CRE to be significantly inferior to its actual production cost.
• Alternative suppliers will lose access to low-cost nuclear electricity, challenging their business models. They have to revise their sourcing strategies, manage increased exposure to wholesale market volatility, and redesign their offers to remain competitive and financially viable.
• Industrial clients — particularly electro-intensive ones — will need to revise their procurement strategies (e.g., PPA, self-consumption) and absorb the increase in electricity prices (+10–20 €/MWh compared to ARENH), either by passing it through to their customers, accepting a margin reduction, and/or improving operational efficiency.

Conclusion: A defining moment for France’s nuclear market

The phase-out of ARENH and the introduction of the VNU–CAPN framework represent a structural transformation of the French electricity market. Beyond regulatory compliance, this shift requires suppliers, industrials and investors to rethink their positioning, secure resilience and capture long-term value.

How Eight Advisory can support

At Eight Advisory, we bring a unique combination of sector expertise, strategic insight, and operational execution to help our clients turn this disruption into an opportunity:

• For electricity suppliers: redefine sourcing strategies, structure competitive commercial offers, and implement advanced risk management frameworks to sustain profitability in a post-ARENH market.
• For industrial off-takers: define and implement performance improvement programs, develop resilient procurement strategies, model exposure scenarios, and structure long-term contracts (PPAs, CAPN, self-generation) to ensure cost predictability and competitiveness.
• For investors and asset owners: assess the impact of the new regime on asset valuations, stress-test business models under different market and regulatory scenarios and identify levers for value creation across the energy value chain.

By combining strategic foresight with hands-on financial and operational expertise, Eight Advisory acts as a trusted partner to navigate uncertainty, design actionable solutions, and secure sustainable competitive advantage in the evolving French energy landscape

Feel free to contact us if you have any questions.

About the authors

Lionnel Gérard and Florian Revellat are Partners in Infrastructure, Energy & Project Finance and in Strategy & Operations, respectively. Thibault Lesage is a Director in Strategy & Operations. Tom Peres and Francis Youyo are Senior Consultants while Victoire Dumon is an Analyst within the Infrastructure, Energy & Project Finance team.

All contributors to this article are part of our Infrastructure & Energy team combining strategic and financial expertise to advise on energy and infrastructure transactions, debt raising processes and regulatory transformations.