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Nuclear energy

Advanced nuclear sector knowledge, at your service

Nuclear power plant

OLKILUOTO 3, ​Picture: TVO

VTT is a broad-scope contributor in international nuclear research. We provide contract services internationally - about 20% of commercial assignments are coming from abroad. VTT is independent and has a solid reputation as the leading Technical Support Organisation of the Finnish nuclear safety authority (STUK) for more than 30 years.

  • 200 professional staff members offering international-class research and broad technological backgrounds
  • Nuclear-focused knowledge, methods and software for safety analysis, engineering, simulation, testing, and training


The Centre for Nuclear Safety in Espoo hosts our brand-new multi-disciplinary laboratories and research facilities, all under one roof.​

Learn more about VTT's Nuclear infrastructure and download brochures: 


​We offer tailored solutions based on pioneering results of domestic and international research. We provide training and knowledge transfer as part of our offerings.
We differ from many others by higher level of maturity and reputation – we always deliver substantive results.
Our customers:
  • NPP operators, utilities
  • NPP designers, equipment vendors and suppliers
  • Radwaste management organizations
  • Nuclear safety authorities
  • Research organizations
  • Government organizations

​Expertise and R&D for the safe use of nuclear energy

  • ​Full range of analyses to support NPP design licensing, plant modernisation and upgrade
  • Everything related to NPP reliability – prediction, diagnostics, failure analysis and rapid problem-solving
  • Multi-disciplinary solutions for the disposal of nuclear and radioactive waste
  • Independent reviews – our conclusions are trusted by nuclear safety authorities

Solutions and services for improved economics of the NPP


Nuclear safety analysis and licensing support

VTT is the key provider of technical support to the Finnish nuclear authority. We provide services to our domestic nuclear industry and have more than two decades' experience in providing technical support and research services to foreign utilities, industries and regulatory bodies. An active member of the European Technical Safety Organisations Network (ETSON), VTT supports nuclear safety authorities in countries that are licensing and executing new nuclear builds. Read more...

​​​Apros - Dynamic Process Simulation

Apros is a simulation software product developed by VTT and Fortum for simulation of combustion and nuclear power plants.

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​​​Assessment and safety justification

VTT offers modelling and analysis methods and tools to the industry and regulators. Our independent assessment services cover a wide range from environmental testing and reliability analysis.

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​​​​FinPSA risk assessment tool

​FinPSA is a risk and reliability analysis tool intended for full scope PRA/PSA modeling. FinPSA is designed to support the main activities related to PRA/PSA

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​​​Model checking for automation

Model checking is an efficient method for supplementing e.g. safety analyses of instrumentation and control (I&C) systems in nuclear power plants

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​Human factors in systems engineering

​Successful design solutions need to be appropriate for their purposes and fit for human use. We provide services that place human experience and mindful human control in the centre of system design.

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Optimising nuclear plant life management & material performance

Optimising nuclear plant life management

​VTT helps nuclear power plant owners, operators and suppliers to maintain ideal conditions and to maintain component life at optimal levels.

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Advanced nuclear technologies

​​​Advanced nuclear technologies

VTT is committed to the development of next generation nuclear technologies through advanced computer modelling and software. Nuclear authorities use our models for next generation reactor safety modeling and the characterisation of steel-based materials.

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Nuclear waste management and disposal

​​​Nuclear waste management and disposal

How do you permanently dispose of nuclear wastes so that it does not harm future generations? VTT has been refining the answer to this very question for over 30 years. In that time we have played an active role in developing practical Finnish and Swedish waste management solutions for high level nuclear waste

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Decommissioning of FiR 1 nuclear reactor

​​​Decommissioning of FiR1 nuclear reactor

​The FiR 1 research reactor, which has served as a key nuclear energy and educational research facility for 50 years, was shut down permanently on 30 June 2015. VTT is applying for a decommissioning licence from the Council of State in 2017.

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Discover what collaboration with VTT can achieve:

​​Interested? Find out more


We will be glad to discuss how to help you

It’s easy to order the work from VTT – just give us the description of your need or challenge, or invite us to visit you.   

 ​We are interested in:

  • Contract research, consultancy and expert services
    Tailor-made to your needs. Results are confidential and delivered exclusively to you for full benefit


  • Jointly-funded public research
    Carried out and funded in cooperation with businesses and public funders (EU, national funds, etc.) and/or other partners. Costs, risks, results and benefits are shared with all the participants


  • Knowledge transfer projects
    We help to develop skills and capacities within your organization, as necessary to cover your long-term needs


  • Licensing of intellectual property
    We provide you with methods, tools, and techniques protected by intellectual property rights


The VTT Centre for Nuclear Safety in Espoo features brand-new multi-disciplinary laboratories and research facilities for radioactive materials. The modern hot cells offer safe nuclear R&D of irradiated materials. Take a look!




Quality of the results you get

VTT’s quality management for nuclear power plant applications is capable of meeting the requirements of the nuclear sector, in particular, when providing engineering and testing services and computer software. For example:

  • ISO 9001:2008
  • STUK Guide YVL A.3
  • NQA-1-2015
  • IAEA GSR Part 2
  • 10 CFR Parts 21 and 50 Appendix B
  • ANSI N 45-2.


VTT’s testing and calibration activities comply with applicable requirements of ISO 17025:2005 standard.
Accreditation of testing and calibration activities is given by FINAS.


3-4 February 2020, Manchester, UK
THERAMIN (thermal treatment for radioactive waste minimisation and hazard reduction) final conference

22-26 March, Helsinki, Finland
European Research Reactor Conference 

25 March 2020, Espoo, Finland
Additive manufacturing in nuclear applications

22–24 April 2020, Rome, Italy
SNETP Forum 2020

10–12 June 2020, Aix-en-Provence, France
INCEFA+ (environmentally assisted fatigue in metallic structures) final seminar and workshop
23-25 June, 2020, Paris, France
World Nuclear Exhibition 


9-10 September 2020, Espoo, Finland
Apros User Group seminar

6–9 October, Granada, Spain
Big Science Business Forum 2020