Analysis of Nuclear Power in Denmark 

Ea Energy Analyses and VTT Technical Research Centre of Finland have carried out an analysis of nuclear power in the form of Small Modular Reactors (SMR) in Denmark. The client is the Danish Energy Agency. 

Denmark’s energy sector has changed a lot since the 1970s. At that time the country relied heavily on oil, but since then the focus has shifted toward energy efficiency, diversification of energy sources, and the expansion of renewable energy. By 2023, renewable energy accounted for more than 80% of Danish electricity production. Danish energy policy and the development of renewable energy have usually been shaped through broad political energy agreements. Nuclear power is formally regulated by the Nuclear Installations Act from 1976, but since 1985 Danish energy planning has been carried out without nuclear power, and the Electricity Supply Act prevents nuclear power plants from being built.

In recent years there has been increasing interest in new nuclear technologies, especially Small Modular Reactors (SMRs), both in Denmark and across the EU. This interest is linked to the continued development of these technologies, the need to maintain stability in energy systems with large shares of wind and solar power, growing interest from industry, and a stronger focus on European energy independence.

On 14 May 2025, the Danish Parliament stated that green electricity from wind and solar will remain the cornerstone of Denmark’s energy supply and that conventional nuclear power is not considered relevant in Denmark. At the same time, the government was asked to carry out an analysis examining the potential and risks of new nuclear technologies and the possible consequences of removing the current ban on nuclear power.

Following this decision, the Danish Energy Agency launched a study on nuclear power in September 2025.

We have five main observations and conclusions from the analysis: 

1. The most mature SMR technologies are based on light water reactor (LWR) designs. They could be put into serial production in the period 2030-2035 if demonstration projects succeed and substantial investments are made. 
   
2. There are no reference data for SMRs operation or costs in the Western world. The developed cost reduction scenarios are therefore highly uncertain. 
   
3. Construction costs must decrease substantially in order to make SMR technologies competitive with RE technologies in the Danish energy system. 
   
4. If it is possible to utilize heat for district heating purposes (combined heat and power), the system value of SMR will increase by more than 30%. SMR with heat utilization becomes cost competitive in Denmark shortly after 2040 in the Central cost reduction scenario. 
   
5. SMR without heat utilization must follow a development path close to the optimistic cost reduction scenario in order to become cost competitive in Denmark (and a number of other European countries) towards 2050.