Author: Karolina Pawlik & Mateusz Gibała

Nuclear energy has long been a pillar of Sweden’s energy mix, although its significance has been diminishing due to divergent policies towards nuclear energy. In recent years, the debates regarding nuclear energy have intensified as the Swedish government, led by the Tidöpartierna coalition, has undertaken a bold reversal of the earlier nuclear phase-out policy. This analysis synthesises the historical, political, scientific, and economic dimensions of Sweden’s evolving nuclear landscape while highlighting the diverse views of political parties and the broader implications for energy policy.

A Historical Context and Policy Shift

Sweden’s relationship with nuclear power is rooted in the 1970s oil crisis, which spurred massive investments in nuclear technology. However, the 1980 referendum revealed deep divisions, ultimately setting the stage for a phase-out policy that prevailed for decades. In 2010, the Swedish parliament (Riksdag) cautiously permitted the construction of new reactors, provided they replaced existing ones—a compromise reflecting Sweden’s complex political and social consensus on energy.[i]

The political landscape shifted dramatically in the 2022 elections when the Moderate Party (M), Christian Democrats (KD), and Liberals (L) formed the Tidöpartierna government, supported by the Sweden Democrats (SD). These parties promised during the 2022 election campaign that they will champion nuclear energy. In contrast, the Social Democratic Party (S), traditionally the dominant political force, has historically had more ambivalent approach to nuclear energy, with various key politicians being either for it or against it.[ii] However, as part of the coalition with the Green Party (MP), which staunchly opposes nuclear energy on environmental and safety grounds, the Social Democrats agreed to a gradual phase-out of nuclear energy. Moreover, in 2015 the Löfven I government (a coalition government of Social Democrats and the Green Party) decided to raise taxes on nuclear energy, thus accelerating the closure of reactors like Ringhals 1 and 2.

Despite this historical ambivalence, in the last quarter of 2023, the new government made two major decisions. First, it repealed the longstanding ban on new nuclear facilities, amending both the Environmental Code (miljöbalken) and the Law on Nuclear Activities (lagen om kärnteknisk verksamhet). [iii] Second, in November 2023, the government unveiled a roadmap (färdplan) to reintroduce new nuclear facilities to the energy mix, aiming to build a 2,500 MW nuclear power plant by 2035. By 2045ten large scale reactors are envisioned, although the exact number and type of reactors needed will depend on several factors: like demand for electricity, the rate of expansion in the power system, technological developments. [iv]

As of 2025 nuclear energy continues to play a critical role in Sweden’s energy system, contributing around 30% of electricity production. [v] Currently, six active nuclear reactors operate at three sites: Forsmark, Oskarshamn, and Ringhals.

Comprehensive Inquiries and Institutional Steps

To align laws and procedures with this new focus on nuclear energy, the government has  launched three comprehensive inquiries:

• A new environmental assessment and permitting process, published in January 2025;[vi]
• A comprehensive review of nuclear waste management (forthcoming in late 2025);
• A review of nuclear preparedness (to be published in 2026).

These inquiries reflect the government’s intent to create a robust framework for nuclear expansion and to ensure long-term policy stability.

Driving Factors Behind the Policy Shift

The government’s pro-nuclear stance is driven by several key factors. Firstly, electricity demand in Sweden is projected to double by 2045, according to official estimates.[vii] Secondly, rising electricity prices in recent years have threatened Swedish businesses’ competitiveness, making reliable and predictable electricity supply a top priority. Finally, Sweden’s global climate leadership has raised the political stakes: large-scale electrification of industry and transport is central to achieving climate neutrality, and nuclear energy is seen as essential to meeting these goals. The Swedish national goal for a fossil-free economy has been pushed forward five years, namely from 2045 to 2040. [viii] This further illustrates the government’s ambitions regarding Sweden’s role in striving for climate neutrality.

As the government is rather determined with pursing its revived nuclear policy, there is a growing hesitation among Sweden’s academic and expert community about the policy and its long-term costs.

Scientific and Expert Perspectives

A growing number of Swedish experts and scientists have questioned whether nuclear energy is the optimal solution for Sweden’s evolving energy system. A notable study by Lisa Göransson and Filip Johnson analysed three potential scenarios to meet rising electricity demand.[ix] Notably, only one of these scenarios includes nuclear energy—at 9,000 MW, approximately the level of nuclear power Sweden had in 2015. The other two scenarios rely on investments in battery storage, biogas, hydrogen, and energy imports (the “optimal cost scenario”) or a massive 22,000 MW offshore wind buildout.[x] The authors conclude:

“It is entirely possible to meet the demand for electricity in an electricity system with a significant share of weather-dependent power generation, including scenarios without nuclear power. In all of the studied cases, we demonstrate that by combining different measures for flexibility, variations in the electricity system can be balanced in a cost-effective way.”[xi]

Adding to this debate, Henrik Ny and Martin Prieto Beaulieu’s study suggests that despite projected doubled energy demand, Sweden can balance its energy system through more intensive investments in energy efficiency and renewables, without large-scale nuclear.[xii] Their analysis compared five scenarios, taking into account lifecycle costs (LCOE). They concluded that the government’s preferred scenario—massive nuclear expansion—would be SEK 470 billion (about PLN 185 billion) more expensive than a scenario prioritizing renewables and energy efficiency.[xiii] Moreover, the authors argue that their preferred scenario with new investment in renewable energy and considerable energy efficiency endeavours will be more manageable and significantly cheaper and could be implemented much more quickly.

However, there are also experts who support the government’s emphasis on nuclear. They argue that critics focus on the electricity generation system, overlooking the wider perspective of the energy system.[xiv] In order to transform entire sectors of the economy and more away from possible fuels, Sweden needs to have stable source of energy and according to proponents of the government’s energy policy nuclear offers reliability and price stability.[xv]

Government Treads Through, while Obstacles Mounts

Despite these scientific arguments, the government has largely dismissed expert criticisms. As national elections loom in 2026—and with the opposition currently enjoying a 6-8 percentage point lead—the government appears determined to fast-track nuclear expansion. Both Prime Minister Ulf Kristersson and Deputy Prime Minister Ebba Busch have publicly declared that construction of Sweden’s first new nuclear power plant in 40 years will begin during the tenure of this government.[xvi]

However, this accelerated timeline has faced significant pushback from regulators and industry stakeholders. Vattenfall, the operator of existing nuclear plants, has declined to commit to any specific schedule. More pointedly, the Swedish Radiation Safety Authority (Strålsäkerhetsmyndigheten) has warned that the permitting process—vital for safety—requires two to three years and cannot be shortened.[xvii] Additionally, Michael Knochenhauer, head of the Authority, has flagged a serious staffing shortage that will persist until next year.

Financing is another contentious issue. In 2024, the government announced that it would fund new nuclear builds through a state loan, guaranteeing electricity prices for 40 years for nuclear operators (contract for difference).  In May 2025, Riksdag (the Swedish Parliament adopted legislation which provides state loans to construction companies and operators of nuclear plants. The new law will come into force in August 2025. The estimated cost of constructing four new reactors stands at SEK 400 billion (about PLN 157 billion or EUR 37 billion). The opposition has scorned the financing model as a “dine and dash” approach, and experts have echoed these criticisms.[xviii]

There are two plausible explanations for the government’s accelerated timeline. One is pragmatic: business groups argue that high electricity prices and unreliable supply threaten Sweden’s competitiveness, pressuring the government to deliver on its pro-business, pro-nuclear agenda from the 2022 elections. The second explanation is political: with the opposition’s lead in the polls and divergent views on nuclear within their ranks (including the S, V, MP, and C), the Tidöpartierna coalition aims to entrench nuclear policy before the 2026 elections, ensuring continuity of their agenda.

Prospects for Political Consensus

Sweden’s political culture is uniquely suited to forging consensus on complex policy questions. Sweden’s political system is defined by constitutional monarchy, minority parliamentarism, and a long tradition of cross-party compromises. Pragmatism and a willingness to collaborate enable the development of shared solutions even on contentious issues like nuclear energy. Moreover, Swedish politics is characterized by stability and incremental reform, typically reflecting broad social and economic realities.

Political Parties’ Positions

Sweden’s major political parties reflect a broad spectrum of views on nuclear energy, shaped by evolving energy needs and climate imperatives:

• Social Democratic Party (S) [xix]: Historically ambivalent, the S has leaned toward phasing out nuclear reactors in favour of renewables, particularly when governing with the Green Party (MP), which strongly opposes nuclear power. In 2015, the S-led government increased nuclear energy taxes, which accelerated the closure of Ringhals 1 and 2.
• Moderate Party (M), [xx]Christian Democrats (KD),[xxi] and Liberals (L)[xxii]: Firm supporters of maintaining and expanding nuclear energy, viewing it as a stable, low-carbon source crucial for Sweden’s competitiveness and climate goals. Their electoral victory in 2022 has allowed them to reverse previous phase-out policies.
• Sweden Democrats (SD): SD, which supports the current government, is also in favour of nuclear expansion, citing the currently high energy prices and the need for reliable domestic electricity production.[xxiii]
• Centre Party (C): Traditionally tied to rural areas and renewable energy, the Centre Party has shown more openness to nuclear power in recent years, particularly in light of climate neutrality goals, but the partyis against subsidising it.[xxiv]
• Left Party (V)[xxv] and Green Party (MP)[xxvi]: Both remain strongly opposed to nuclear power, focusing on renewables such as wind and solar to achieve Sweden’s climate targets.

The history of cross-party energy agreements is notable: a 2010 compromise allowed for new reactors at existing sites, and even though the 2019 cross-party energy agreement broke down (as Moderates and Christian Democrats pushed for a greater emphasis on nuclear over renewables), the political system’s pragmatism still points to eventual consensus. Furthermore, Sweden’s robust institutional framework—including the Swedish Energy Agency (Energimyndigheten) —reinforces the likelihood of compromise. These technocratic agencies often play an apolitical role in policy development, fostering evidence-based decision-making that supports consensus

Implications for Europe and Poland

On the European stage, Sweden’s nuclear expansion also has geopolitical implications. As of spring 2025, three major technology providers are competing to support the Swedish nuclear push: the French EDF, the American Westinghouse and South Korean KHNP. Westinghouse, already the technology provider for the Ringhals plant, represents a transatlantic partner, while EDF leverages its European credentials and extensive continental experience. This competition underscores Sweden’s balancing act between European strategic autonomy and transatlantic security ties.

The Swedish nuclear debate resonates well beyond its borders, offering valuable lessons for other European countries grappling with the same dilemmas. Sweden’s methodical approach—launching clear roadmaps and conducting comprehensive inquiries — somewhat contrasts with how Poland is going about its nuclear policy. However, what is lacking from the Swedish nuclear debate is a greater willingness of the government to take into account dissent voices like those of the scientific community.

Concluding Insights

As of early 2025, the Swedish government remains committed to advancing  the civil nuclear programme despite scientific critique and political opposition. Two years have already passed since the announcement of the nuclear roadmap, and Sweden has taken concrete steps to revise the regulatory framework, secure financing, and engage technology providers. The debate within Sweden is dynamic and merit-based, offering space for both proponents and critics of nuclear energy to articulate their visions.

Yet, Sweden’s pragmatic and consensus-oriented political culture suggests that a final settlement—one that balances nuclear energy with investments in renewables and energy efficiency—is ultimately likely. Sweden’s example underscores a critical truth for all democracies navigating the 21st-century energy transition: achieving climate neutrality, energy security, and economic competitiveness requires not only technical innovation but also political maturity, transparency, and the courage to engage in open debate.

References

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[ii] M. Valestrand,   « Den socialdemokratiska kärnkraftens dubbla liv» https://www.energi.se/artiklar/2022/juni-2022/den-socialdemokratiska-karnkraftens-dubbla-liv/ (accessed 23.05.2025)

[iii] Regeringen, «Regeringens proposition2023/24:19 Ny kärnkraft i Sverige – ett första steg» https://www.regeringen.se/contentassets/9e9319a8ecfd4939bedcd50dfb0bc00d/ny-karnkraft-i-sverige–ett-forsta-steg-prop-20232419.pdf   (accessed 23.05.2025)

[iv] Regeringen, «Regeringen lanserer en färdplan för ny kärnkraft i Sverige» https://www.regeringen.se/pressmeddelanden/2023/11/regeringen-lanserar-en-fardplan-for-ny-karnkraft-i-sverige/ (accessed 23.05.2025)

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[v] Regerigen, «Fragor och svar om kärnkraft» https://www.regeringen.se/regeringens-politik/energi/fragor-och-svar-om-karnkraft/ (accessed 23.05.2025)

[vi] Regeringen, En ny samordnad miljöbedömnings- och tillståndsprövningsprocess, Stockholm (2024), p.44-45

[vii] Op cit. Regeringen, «Regeringen lanserer en färdplan för ny kärnkraft i Sverige»

[viii] Regeringen, «Färdplan för ny kärnkraft i Sverige» https://www.regeringen.se/globalassets/regeringen/dokument/klimat–och-naringslivsdepartementet/ppt/231116-presentationsbilder-fardplan-for-ny-karnkraft-i-sverige.pdf (accessed 26.05.2025)

[ix] L. Göransson, F. Johnson,  Ett framtida elsystem med och utan kärnkraft – vad är skillnaden? Göteborg (2023)

[x] Ibid., p. 11

[xi] Ibid., no page number

[xii] H. Ny, M. Prieto Beaulieu, «Ny kärnkraft eller effektiviseringoch ny förnybar energi för ettkostnadseffektivt svenskt elsystem?»  Blekinge Institute of Technology Research Report nr 2023:03,  (2023), p. 1-32

[xiii] Ibid. p. 24

[xiv] H. Stenegren, J. Broman, «Därför tänker regeringen rätt om kärnkraften» https://timbro.se/smedjan/darfor-tanker-regeringen-ratt-om-karnkraften/ (accessed 26.05.2025)

[xv] Ibid. H. Stenegren, J. Broman, «Därför tänker regeringen rätt om kärnkraften»

[xvi]  T. Ekelund,  «Kristersson: Börjar bygga ny kärnkraft före valet» https://omni.se/kristersson-borjar-bygga-ny-karnkraft-fore-valet-2026/a/LMj5oR (accessed 29.05.2025)

[xvii] SVT, «Regeringens tindsplan för ny kärnkraft håller inte» https://www.svt.se/nyheter/inrikes/regeringens-tidsplan-for-ny-karnkraft-haller-inte (accessed 29.05.2025)

[xviii] SVT, Oppositionen kristis till kärnkraftförslag – springnota» https://www.svt.se/nyheter/inrikes/oppositionen-kritisk-till-karnkraftsforslag-springnota (accessed 29.05.2025)

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[xxi] Kristdemokraterna, «Energi» https://kristdemokraterna.se/var-politik/politik-a-till-o/energi (accessed 29.05.2025)

[xxii] Liberalerna, «Energi» https://www.liberalerna.se/politik/energi (accessed 29.05.2025)

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[xxiv] Centerpartiet, «Energi», https://www.centerpartiet.se/var-politik/politik-a-o/energi (accessed 29.05.2025)

[xxv] Vänsterpartiet, «Energi» https://www.vansterpartiet.se/var-politik/politik-a-o/energi/ (accessed 29.05.2025)

[xxvi] Mijlöpartiet, «Energi» https://www.mp.se/politik/energi/ (accessed 29.05.2025)