We are currently in a transitional phase to a diverse low-carbon energy future where we believe nuclear and renewables have a key part to play. We aim to incorporate sustainability principles and standards into all stages of the generating lifecycle to ensure we design, construct, operate and decommission our generating assets safely and responsibly. Our aim is to be world leaders in the field of nuclear operational excellence, and we are committed to addressing environmental, financial and stakeholder expectations.

Building sustainably

Our goal is to incorporate sustainability principles and standards into our nuclear design and engineering, project processes and criteria.

It is important to understand the opportunities and impacts that can arise throughout the lifecycle of our stations. A large proportion of the impact of our nuclear stations is down to the way they are initially designed and built, and in the design and construction of modifications during their operating lives. We are therefore working to embed sustainability principles and standards into our new generation builds and other projects right from the beginning.

How we measure progress


To embed sustainability principles and standards in our generation development projects:

• Sustainability principles and standards incorporated into design & engineering and project processes and criteria

How are we doing


As part of the construction of Hinkley Point C, several associated development sites have been started and completed during 2018.

We are also working to embed sustainability principles into:

  • Our new nuclear generation builds Hinkley Point C (HPC) and other projects (including battery storage) from the beginning.
  • Processes and operations across our existing nuclear fleet.
  • Our plans for decommissioning our nuclear stations.


Underpinning this, our existing nuclear fleet operates in accordance with international standards.

Working with our supply chain partners is essential and our successes will also contribute to many of our target areas, particularly our net zero environmental impact strategic goal.


Our sustainability requirements are detailed in the Environment and Sustainability Appendix, which is part of the works Information in every contract. This details our expectations of our supply chain from specifying prefabricated/modular buildings and incorporating recycled content in materials to specifying FSC timber as per the Development Consent Order.

In addition to this our Sustainable Materials Policy is also sent out with all contracts and provides guidance on sustainable procurement. 

Safety and efficiency

Nuclear safety is our overriding priority. Our aim is to be world leaders in the field of nuclear operational excellence.

Making sure our low-carbon electricity supply and sites are secure is integral to keeping our people and our communities safe. We will continue to deliver the highest standards of nuclear safety in our existing operations and our new build projects.

We have a strong, open reporting culture and also implement international standards of best practice allowing us to continually address any improvement opportunities. This means all issues, whether nuclear reportable events or minor deviations, are reported and prioritised. We then take appropriate action to make sure they don't happen again. By learning from these incidents we can continuously improve safety and operational performance. 

Our programmes


Our nuclear safety policy is most effective when supported by a strong and positive nuclear safety culture. Therefore, we have worked to adopt and develop the ten traits of a healthy nuclear safety culture from the World Association of Nuclear Operators, such as taking personal responsibility for safety and having a questioning attitude.  

These strong safety processes and healthy nuclear safety cultures have also been embedded in our plans for constructing and operating our new nuclear build sites. Ten traits of a healthy nuclear safety culture from the World Association of Nuclear Operators:

  1. Personal accountability: All individuals take personal responsibility for safety.

  2. Questioning attitude: Individuals avoid complacency and continuously challenge existing conditions and activities in order to identify discrepancies that might result in error or inappropriate action.

  3. Effective safety communication: Communications maintain a focus on safety.

  4. Leadership safety values and actions: Leaders demonstrate a commitment to safety in their decisions and behaviours.

  5. Decision making: Decisions that support or affect nuclear safety are systematic, rigorous and thorough.

  6. Respectful work environment: Trust and respect permeate the organisation.

  7. Continuous learning: Opportunities to learn about ways to ensure safety are sought out and implemented.

  8. Problem identification and resolution: Issues potentially impacting safety are promptly identified, fully evaluated, and promptly addressed and corrected commensurate with their significance.

  9. Environment for raising concerns: A safety conscious work environment is maintained where personnel feel free to raise safety concerns without fear of retaliation, intimidation, harassment, or discrimination.

  10. Work processes: The process of planning and controlling work activities is implemented so that safety is maintained.


EDF Energy operates its nuclear power stations to high safety standards and under scrutiny from the independent UK government regulator, the Office for Nuclear Regulation (ONR). We report any deviations to our safety standards to the ONR, however small, so they can be prioritised and addressed. Open reporting in this way is an important element of our nuclear safety culture and is positively encouraged throughout the organisation.


We follow strict procedures to minimise and control the radiation doses our employees and contractors receive at our nuclear power stations. Additionally  anyone required to enter a radiologically controlled area is issued with an electronic personal dosemeter. This warns the wearer if their dose exceeds a pre-determined level and also allows us to record any longer term exposure.


We want our existing nuclear plants to be running safely and at their highest possible capacity to deliver the most low-carbon electricity to the UK. This measure helps us understand how effective we are in maintaining and investing in the reliability of our existing stations.

In order to maintain our fleet of stations in good working order, we have a schedule of planned plant maintenance, inspection and testing including outages that ensure the plant is always in good, safe working order and is upgraded as required. However sometimes unplanned shutdowns or reductions in generation do occur and these are implemented in a controlled way with conservative decision making applied to ensure that nuclear safety is always given the top priority. We report the daily status of our stations.

How we measure progress


To achieve world class standards of nuclear operational excellence:

By 2020 zero nuclear reportable events

• In 2018 collective radiation exposure 1140 man mSv (targets are set on an annual basis)

• By 2020, unplanned capability loss factor to be in the upper quartile of worldwide operator performance

How are we doing

Nuclear safety is our overriding priority. The UK’s nuclear industry has an excellent safety record going back more than 50 years. Our nuclear power stations are built to the highest and most exacting international standards, and can withstand earthquakes, floods and fires. Independently regulated by the Office of Nuclear Regulation, we comply with some of the toughest nuclear regulations in the world.

In addition to a successful operational performance during 2018, we continue to embed sustainability principles into all aspects of nuclear generation. This includes our new nuclear construction project at Hinkley Point C, our processes and operations across our existing generation fleet and in our ongoing plans for decommissioning.

Sustained investment in our nuclear fleet is helping to provide secure, resilient and low carbon power for the UK. 


Nuclear safety remains our overriding priority and we have continued to perform well across our primary performance indicators. Only two nuclear reportable events have occurred in the past six years, one in 2017 and one in 2018, with our robust maintenance and safety processes helping to ensure this performance continues through 2019.

Our one year collective radiation exposure is set on an annual basis depending on any planned outages, our performance in 2018 was 797 man mSv against a target 1140 man mSv. The graph below shows our 3 year rolling average per reactor because the periodic nature of statutory outages can distort the annual trend.


Operational performance during 2018 was adverse to plan following  extended shutdowns at Hunterston B and Dungeness B.

At Hunterston B scheduled graphite inspections in early 2018 confirmed the expected presence of new keyway root cracks in reactor 3 core and also identified these happening at a slightly higher rate than modelled. A conservative decision was taken to keep the reactor offline to allow further analysis to take place.

At Dungeness B the discovery of corrosion and steam line cracking meant that the outages were extended through November and December 2018.

Investment over the last decade in people, plant and process improvements have substantially reduced our small unplanned losses, delivering the equivalent of an additional nuclear power station in terms of increased yearly output, avoiding significant carbon emissions for the UK. Work continues to underpin the return to service for Hunterston B and Dungeness B in 2019.

Collective radiation exposure

Unplanned Capability Loss Factor

Our energy legacy

Our goal is to ensure our energy legacy is managed safely and responsibly. 

We are committed to addressing environmental, financial and stakeholder expectations. We are working to incorporate good sustainability principles and standards into the decommissioning plans that govern the end of our stations’ generating lives.

Of our eight nuclear stations, most will commence decommissioning during the 2020s. The last will be Sizewell B, currently scheduled for 2035. Generating nuclear power and the decommissioning of our stations produces radioactive waste and spent fuel. Most of this radioactive waste is low-level and can be incinerated or buried in shallow ground. The small amount of higher activity waste and spent fuel that is produced needs to be shielded from people and the environment for many years. 

Our programmes


Decommissioning involves removing all spent fuel and then deconstructing the site over many decades and managing the associated radioactive waste that is produced during the process. At the end of decommissioning, the power station sites will be returned to their original state, with no restrictions on their future use.

We already have Baseline Decommissioning Plans (BDP) for all our existing stations. These set out the strategy and associated cost estimates for decommissioning and are updated every three years. In 2016 we increased focus on the preparation works for decommissioning, preparing more detailed defueling and decommissioning plans, in advance of 2023, when we expect our first stations to end their operating lives.

The funding for the decommissioning and waste management of EDF Energy’s existing nuclear sites comes primarily from the Nuclear Liabilities Fund (NLF), into which we have been paying for many years. This is administered by the Nuclear Liabilities Fund Trustees- independent of EDF Energy and UK Government. We will start to receive funding for the first stages of decommissioning in 2017.


Our Nuclear New Build teams have worked with Radioactive Waste Management Limited to show how we will safely and securely dispose of spent fuel and radioactive wastes from our new power stations, such as Hinkley Point C. The Energy Act 2008 requires the operator of a new nuclear power station to provide secure financing arrangements to meet the full costs of decommissioning and waste disposal before construction can begin.

Hinkley Point C will be the first nuclear project to have a Funded Decommissioning Programme which was approved by the Government in 2015. We are proud to be setting this precedent, which ensures we are taking full responsibility for our power station from start to finish.


We’re working with the UK Government, non-governmental organisations and others to develop a UK Geological Disposal Facility (GDF) as a long-term solution to radioactive waste.

The UK Government’s preferred solution, supported by EDF Energy, is to construct a single underground site known as a Geological Disposal Facility (GDF). As a producer of radioactive waste and spent fuel, we contributed to the consultation on the GDF, emphasising its importance to our existing and future operations.

The Scottish Government’s policy is to store waste near the surface, near the nuclear site that produced it. We will follow this policy for our two nuclear power stations in Scotland.

We have a suite of governance arrangements to manage conventional and radioactive waste across our fleet. In the context of radioactive waste and spent fuel management, which we work to on an ALARP (as low as reasonably practicable) basis, which is one of the fundamental principles of risk management. We neither need nor want to manage risk to the point where we eliminate it, because doing so is simply not a good use of resources.

We have the following aims:

  • Reducing generated radioactive waste and optimising spent fuel

  • Effectively using the waste management hierarchy

  • Using reprocessed uranium in our existing fleet of power stations where appropriate

We continue to explore the options for and fund research in reusing spent fuel material in future reactor designs and also optimise end of life fuel usage for older AGRs. The safe management of radioactive waste on nuclear licensed sites in the UK is regulated by the ONR under the Nuclear Installations Act 1965 (as amended). Radioactive waste disposal is regulated by the Environment Agency in England and Wales and by the Scottish Environment Protection Agency in Scotland.

In the UK, solid radioactive waste is classified into four categories:

  • Low Level Waste (LLW), for which a near surface disposal route exists – Including the LLW Repository at Drigg West Cumbria.

  • Intermediate Level Waste (ILW), for which no disposal route is currently available in the UK; although we continue to provide support to the Government on a long-term solution.

  • High Level Waste (HLW) is defined as radioactive waste in which the temperature may rise significantly as a result of the radioactivity, so this factor has to be taken into account in the design of storage and disposal facilities.

  • Higher Activity Waste (HAW) - this is effectively HLW, ILW and any LLW that are unsuitable for near-surface disposal.

Examples of LLW include: redundant equipment; waste from maintenance activities; plastic; rubble; old protective clothing from our nuclear power stations; used filters and resins. HLW results from the reprocessing of AGR fuel at Sellafield. HLW contains high levels of radioactivity which generates heat. There is no HLW stored on any EDF Energy power station. Spent nuclear fuel is not considered to be waste until a decision has been made to dispose of it.

Further information and waste performance data


How we measure our progress


To ensure the safe and responsible management of our energy legacy:

• Sustainability principles and standards are incorporated into decommissioning and deconstruction plans

How are we doing


Although highly active waste and spent fuel can be stored safely on our sites for many years, securing a permanent, long term disposal solution is a key priority for us.

Since our stations started operating we have been collaborating with Government to help achieve their goal of developing a safe and secure long-term disposal facility. As the UK’s only generator of electricity from nuclear power, we take our responsibility in this task very seriously and our support to Government will continue throughout 2019 and into the years ahead. Although not in place for our Advanced Gas Cooled Reactor (AGR) fleet, at Sizewell B we have created a facility to safely store the station’s spent fuel until a Geological Disposal Facility becomes available for longer term storage.

We have continued to develop our decommissioning plan for current and future operations. As part of this, we are mapping the UK waste and decommissioning environment and considering potential areas for research and development throughout 2019.