ARENH

The Accès Régulé à l'Énergie Nucléaire Historique (ARENH) was France's framework for opening EDF's nuclear generation to competing electricity suppliers at a below-market regulated price. Created by the NOME law (Loi n° 2010-1488) of 7 December 2010 and operational from 1 July 2011, it allowed licensed alternative suppliers to purchase up to 100 TWh per year of EDF's nuclear output at a fixed price of EUR 42/MWh. The cap represented roughly 25% of EDF's annual nuclear production, designed to stimulate retail competition without exposing EDF to full revenue risk from new entrants.

ARENH worked reasonably well when wholesale electricity prices hovered near EUR 40-50/MWh, but the mechanism became structurally distorting from 2021 onwards as energy prices surged. At EUR 42/MWh, the regulated price sat FAR below market rates above EUR 200/MWh during the 2022 energy crisis, creating enormous demand from suppliers and a windfall transfer from EDF to retail competitors. Conversely, in periods of low prices, suppliers could simply ignore ARENH and buy cheaper on the spot market, leaving EDF carrying the stranded-cost risk. The 100 TWh ceiling was routinely oversubscribed once prices rose, generating an allocation lottery among eligible suppliers.

ARENH expired on 31 December 2025 and was replaced from 1 January 2026 by two successor mechanisms: the Versement Nucléaire Universel (VNU), which provides a regulated reference price estimated by the CRE at EUR 65.90/MWh for 2026, and Nuclear Production Allocation Contracts (CAPN). The transition ended 14 years of fixed-price subsidised nuclear access and shifted French industrial consumers to a price-linked model. Large users who had relied on ARENH allocations to undercut German and Italian competitors face a step-change in energy costs under the successor regime.