EU: Nuclear Energy Updates - Climate Scorecard

Nuclear power remains a cornerstone of the EU’s energy mix, providing about one-quarter of its total electricity and approximately half of its low-carbon electricity.

Europe’s climate ambitions are embodied in the European Green Deal, which commits the bloc to reducing greenhouse gas emissions by 55% by 2030 and achieving climate neutrality by 2050. While the EU sets binding targets for renewable energy, it leaves decisions about nuclear deployment largely to individual states. Nonetheless, nuclear power remains a cornerstone of the EU’s energy mix, providing about one-quarter of its total electricity and approximately half of its low-carbon electricity. However, the sector is at a crossroads, shaped by divergent national policies, ambitious climate targets, evolving markets, and mounting geopolitical challenges.

Over the past five years, the role of nuclear energy in the EU’s energy mix has declined, despite renewed political debate about its place in the clean energy transition. In 2019, nuclear power accounted for approximately 26% of the EU’s electricity generation; by 2024, it had decreased to around 23–24%, according to Eurostat and Ember figures. When measured against total final energy consumption, nuclear’s contribution is even more modest — just 4.7% across the EU-27, or about 10% in the twelve countries that still operate nuclear reactors. Production in 2024 was higher than in the outage–stricken 2022, but the longer–term trend shows a gradual decline as reactors close and new projects remain scarce.

Consisting of 27 member states, each with its own stance on nuclear energy, the EU’s nuclear landscape is uneven. While countries like Germany have fully withdrawn from nuclear power (with the last three reactors closed in 2023), others are pursuing the long-term operation (LTO) of existing reactors and the construction of new plants. France dominates, with its 56 reactors – out of a total of 100 reactors in the EU – providing nearly two‑thirds of its electricity, generating 54.6% of the bloc’s total nuclear electricity (338 TWh in 2023), followed by Spain (9.2%), Sweden (7.8%), and Finland (5.5%). These four countries collectively produce 76.9% of all nuclear electricity in the EU. Slovakia, Hungary, Finland, and Belgium also rely heavily on nuclear power for electricity generation, in some cases for over a quarter of their power supply.

Most EU nuclear power comes from Pressurized Water Reactors (PWRs), with additional Boiling Water Reactors (BWRs), Pressurized Heavy Water Reactors (PHWRs), and a few advanced designs. The current European trend emphasizes the extension of existing units (LTOs) and, increasingly, the construction of new, more modern reactors, including Generation III and IV designs, as well as the early adoption of Small Modular Reactors (SMRs). There is also substantial EU research and investment in next-generation reactors, including international fusion projects. While advanced designs such as Generation III+ reactors and SMRs incorporate modern safety upgrades, much of the EU’s operating fleet is based on designs from the 1970s and 1980s. The average reactor age is almost 37 years, and without life‑extension programmes, most will retire by 2040.

Building new reactors in Europe remains an expensive and time‑consuming undertaking. High‑profile projects such as France’s Flamanville‑3 and Finland’s Olkiluoto‑3 have taken more than 15 years from start to (near) completion, with costs inflating from initial estimates of €3–4 billion to well over €10 billion. On a per‑megawatt basis, new nuclear investment typically exceeds €10 million, making it more capital‑intensive than wind or solar, whose construction timelines are measured in months rather than decades.

According to the World Nuclear Association, uranium for EU nuclear plants comes from a diversified mix of suppliers — Niger, Kazakhstan, Russia, Australia, and Canada — with fuel fabrication and enrichment largely handled by European firms such as Orano and Urenco, but with some Russian supply, particularly for VVER‑type reactors in Eastern Europe. The EU is actively working to diversify away from Russian nuclear fuel, with restrictions being implemented on new supply contracts and member states building strategic inventories. Alternative suppliers include Namibia and other Central Asian producers.

The oversight of nuclear power in the EU is thorough and multi-layered, although it primarily rests with national nuclear safety authorities. Each member state maintains its own national nuclear safety authority, such as ASN in France or FANC in Belgium, which is responsible for licensing, inspection, and enforcement. At the EU level, bodies such as the European Nuclear Safety Regulators Group (ENSREG) and the European Commission provide coordination, peer review, and oversee the implementation of directives under the EURATOM Treaty. International oversight is provided through the International Atomic Energy Agency (IAEA), which sets baseline norms for reactor use, fuel handling, and waste management. The legal framework for safety, updated after the Fukushima accident, now requires operators to prioritize safety at every stage, under close regulatory supervision.

Managing nuclear waste remains one of the industry’s most persistent and contentious challenges. All EU countries with nuclear plants are required, under the 2011 Nuclear Waste Directive, to establish national programmes for handling spent fuel and radioactive waste. In practice, most rely on interim storage at or near reactor sites. Only a few — notably Finland, Sweden, and France — have advanced plans for deep geological repositories, with Finland’s Onkalo facility expected to be the first in the world to enter operation later this decade. Spent fuel is typically cooled in pools for several years before being transferred to dry cask storage, pending final disposal. Long‑lived high‑level waste must be contained and isolated for timescales of up to hundreds of thousands of years, making repository design both an engineering and a societal challenge.

The coming decade will be decisive. According to Nucleareurope’s economic impact study, expanding EU nuclear capacity to 150–200 GW by 2050 could support over 1.5 million jobs and contribute hundreds of billions of euros annually to EU GDP. Yet, without significant investment and political will, the current trajectory points toward further decline in nuclear’s share, to be offset by the rapid growth of wind, solar, and other renewables. For now, nuclear energy continues to provide a large share of Europe’s low‑carbon, baseload electricity — but its future in the EU hinges on how governments reconcile cost, construction timelines, safety oversight, and long‑term waste management with the urgency of the climate transition. The transition may be nuanced and country-specific—but Europe’s days as a “nuclear continent” may well soon slip into history. The next chapter will be written by the sun, the wind, and the ingenuity of policymakers and citizens working to create a cleaner, more resilient energy system for all.

This Post was submitted by Climate Scorecard EU Manager, Syaliza Musapha.

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