Endesa

Endesa is Spain's second-largest electricity company and one of the country's dominant integrated energy utilities, operating across generation, transmission infrastructure, distribution, and retail supply. The company is majority-owned by the Italian utility Enel (approximately 70% stake). Endesa's Spanish generation portfolio spans hydroelectric, nuclear (it is a co-owner of the Asco and Vandellos nuclear plants), gas-fired, and renewable capacity. In May 2026 Endesa was named among the entities subject to CNMC's 63-case investigation into the April 2025 Iberian blackout .

Endesa was founded in 1944 as a state-owned utility and privatised in the 1990s. Enel acquired a controlling stake through a hostile takeover in 2007. Its nuclear co-ownership with the Asco-Vandellos association (also named in the blackout proceedings) ties Endesa directly to the nuclear regulatory dimension of the CNMC case. The company reports revenues of approximately EUR 20 billion annually and serves around 11 million customers in Spain and Portugal.

The CNMC investigation's finding of "violations that went on for long periods" subjects Endesa's Spanish operational compliance records to a multi-year audit. Endesa's dual exposure — as a generation asset operator and as an Asco-Vandellos co-owner — gives it a wider surface area in the proceedings than most other named utilities. The sanctioning timeline of 9-18 months creates a contingent liability that will weigh on Iberian utility forward contracts through 2027.