TASC would like to correct EDF’s contention that nuclear power is a low carbon source of electricity.  We believe that, in the current climate of crisis over the atmospheric carbon, it is vital that the energy policy the UK pursues is not predicated on assumptions which give a false impression of the carbon footprint of the Sizewell C development.

As part of their promotion of the Sizewell C project, EDF make great claims of nuclear’s ‘low carbon footprint’. While we agree that the operating of the plant itself and the process of generating electricity through the fission process will be more carbon efficient than fossil fuel combustion, it is untrue to claim that the nuclear fuel cycle renders the technology truly ‘low carbon’.  Many authoritative studies show that when the “cradle to cradle” assessment of the carbon footprint of a new nuclear power plant is calculated, a far higher figure than that used by EDF is produced. EDF claim lifetime emissions of 12gCO2e/kWh for nuclear reactors generally and 5gCO2e/kWh for EDF Hinkley Point C. However, studies carried out by others show a figure of more than 50gCO2e/kWh in one meta-analysis reported in the Ecologist magazine and a range of 78-178gCO2e/kWh in another carried out by Mark Jacobson.

Given the climate emergency declared by the UK government and the importance of establishing a sustainable low-carbon economy, we believe all large infrastructure projects need to establish their greenhouse gas emissions credentials. TASC believes that Sizewell C will have a huge upfront carbon debt from the uranium fuel and from its construction and are concerned that this debt will occur in the period that the International Panel on Climate Change, in 2018, said that we need to reduce our carbon emissions by at least 45% to keep the global temperature rise down to 1.5%. For a new nuclear power plant such as Sizewell C, the calculation would need to include the carbon, and other greenhouse gases, produced from activities including:-

  1. i) The mining, milling, fabrication, enrichment and transportation of the uranium fuel needed so the power station is ready for use.
  2. ii) The construction of the power stations and all of its infrastructure (roads, roundabouts, railways, jetties, sea walls, beach landing facilities, cement batching plant, dry fuel stores etc etc) including the mining, processing and transportation of all the materials and transport of staff and contractors.

iii) The operation of the plant including materials and daily personnel transportation (including flights of international specialists) for planned and unplanned outages, replacement fuel and packaging and processing of spent fuel, maintaining and increasing sea defences to deal with rising sea levels and storm surges.

  1. iv) The decommissioning and total dismantling of the power stations and restitution of the site to its original state.
  2. v) The storage of the radioactive waste until such time as it becomes no more dangerous than its original state. There appear to be two basic ways of considering this:-
  3. a) Proposals for a deep Geological Disposal Facility, requiring a programme to accommodate the waste, are still uncertain, making the carbon footprint calculation for the disposal programme difficult if not impossible to assess given the depth, location, volume and configuration of any GDF, should it ever find a willing community to host it, are unknown. In addition, the GDF itself will require a complicated and extensive transport infrastructure. It would be appropriate to calculate the carbon footprint for building one, maybe two nominal repositories which would be the largest ever civil engineering project in the UK with a series of chambers at possible depths between 200m and 1,000m below ground covering several square miles. The thousands of spent fuel assemblies will require thousands of tonnes of copper cladding which will have to be mined and smelted before turning into cylinders and there will of course be processing and transport requirements.
  4. b) TASC believe we have to accept storage of the waste in specially built surface level or just below surface level stores (viz Sizewell B Dry Fuel Store). The carbon footprint calculation will need to take into account the requirement for the site to be protected, maintained, renewed and probably relocated, due to the impact of rising sea levels and increased storm surges, over the millennia.


We submit, therefore, that the claim that Sizewell C along with all other new build developments will produce ‘low carbon’ electricity without the benefit of detailed assessment of the carbon debt created across the nuclear fuel cycle on a ‘cradle to cradle’ basis is false and misleading.

TASC have attempted to determine which government department will take responsibility for assessing the carbon footprint for national infrastructure projects but, as yet, to no avail.

How much carbon would Sizewell C save? Report from Professor Steve Thomas & Alison Downes