Fight Over Nuclear Waste Fees Shapes Spain’s Energy Tax Debate

Power utilities are pushing back against the government’s plan for a steep hike in the fees paid by their nuclear plants. Foro Nuclear, the trade group representing reactor owners such as Iberdrola, Endesa, Naturgy, and EDP, has filed administrative challenges in the Supreme Court to overturn the government’s plan to fund seven proposed nuclear cemeteries and to abandon the outright plan for a single centralized storage facility in Villar de Cañas. They are also calling for a comprehensive review of the taxes shouldered by the reactors as a way to curb the expected rate increase.

The government has moved to pressure the major electric companies by launching a process to increase the levy on nuclear plants by 40 percent. This move aims to cover the multi‑billion euro costs associated with decommissioning all reactors and managing decades of radioactive waste across seven cemeteries. The increase is tied to the new General Plan for Radioactive Waste (PGRR), the government’s roadmap for nuclear waste management, which envisions seven storage sites one at each plant and would raise the overcost to 3.7 billion euros compared with the previous plan for a single storage facility.

Foro Nuclear has lodged administrative challenges with the Supreme Court against the seventh waste plan authorized by the government last December and against abandoning the plan for a single centralized temporary storage facility (ATC) at Villar de Cañas. The nuclear association is urging the National Company for Radioactive Waste (Enresa) to resume the necessary steps to finalize the process that would bring the single cemetery project to fruition.

Opposition to the rate hike

The federation representing the nuclear operators has also submitted joint comments, pro forma with the major electricity producers, regarding a draft royal decree from the Ministry for Ecological Transition. The draft seeks to raise the non‑tax burden that utilities pay for each megawatt hour produced by the reactors to 11.14 euros, up from 7.98 euros per MWh, an increase of about 39.5 percent.

Currently, the nuclear plants contribute a non‑tax levy to Enresa based on the amount of electricity generated. Taken together, Iberdrola and Endesa, along with residual stakes from Naturgy and EDP, pay roughly 450 million euros annually into the fund that finances the nuclear waste plan, which has accumulated about 7.4 billion euros to date.

The government’s proposed increase would push annual payments from the plants to roughly 630 million euros, an extra 180 million compared with current levels. This sharp rise threatens a direct clash between the administration and the utilities, which have long argued that the heavy fiscal burden endangers the economic viability of nuclear operations, even as reactors are seen as a stable backbone of the country’s energy transition due to reliable supply and low carbon emissions.

Fiscal reform considerations

The federation unites Iberdrola, Endesa, and Naturgy in pressing the government to ensure that the mounting costs of waste management do not fall on the reactors alone. They argue that political and institutional gridlock around a single storage solution justifies rethinking the current tax approach. The utilities also seek a comprehensive review of the fiscal framework sustaining the reactors to offset the proposed rise in the Enresa levy.

They advocate that revenues drawn from the taxation on spent fuel and radioactive waste produced by nuclear generation, and from centralized waste storage facilities, should be dedicated to funding the decommissioning and waste management programs rather than being redirected into general public coffers. Redirecting revenue in this way could save about 5 euros per MWh produced, according to Foro Nuclear, surpassing the government’s proposed increase. The group also seeks to exclude from Enresa’s fund the costs associated with the levy on centralized storage of spent fuel and radioactive waste that Enresa itself pays, arguing this cost is ultimately borne by the reactors themselves.

Foro Nuclear notes that Spanish nuclear plants operate under a heavy, sometimes discriminatory tax regime that jeopardizes their operation. Any further tax or levy increases are likely to threaten the economic viability of reactors, which are crucial for energy security and low emissions, especially given delays in wind developments and pump-storage projects that could otherwise offer storage alternatives. The association emphasizes that intact nuclear capacity remains a key element of the energy transition, providing steady supply and carbon-free generation while other technologies scale up.