Used fuel options evaluated for UK

08 October 2007

The UK effort to develop a policy on used nuclear fuel took a small step forward with a report on potential strategies for the management of the uranium and plutonium in its stocks.

The report does not offer any recommendations, but together with an earlier report, gives as detailed an outline as possible of management options that stretch 300 years into the future.

In the early days of the British nuclear power program it was thought that fast reactors which would recycle plutonium and uranium produced by conventional early reactors, and policy was to reprocess that fuel and stockpile reusable materials. However, early fast reactors did not live up to expectations and the UK's development program was stopped. Reprocessing continues, principally at Sellafield where a mixed-oxide (MOX) nuclear fuel plant can also recycle uranium and plutonium in nuclear fuel for conventional reactors, but the government has no long-term policy on used nuclear fuel management other than that high- and intermediate-level radioactive waste arising from nuclear fuel processing should be disposed of in deep underground facilities.

The report, Spent Fuel Management: Life Cycle Analysis Model, written for the Nuclear Decommissioning Authority (NDA) by Integrated Risk Management and Environmental Resources Management Consulting, outlines three general strategies for managing the materials and other used nuclear fuels from early development work and experimental reactors.

The three management strategies for the next 300 years,
also considered by the same consultants for NDA in a June report, Uranium and Plutonium: Macro-Economic Study, are:
  • To treat the used fuel as waste, put it in a form suitable form geologic disposal and proceed with this as soon as possible. This strategy would cost a total of GBP3 billion ($6.1 billion), requiring an investment now of around GBP600 million ($1.2 billion).
  • To store the used fuel for the long-term on the assumption it may have a value at some point up to 300 years in future. This would cost GBP3.6 billion ($7.3 billion), GBP500 million ($1 billion) now.
  • To reprocess the fuel now for recycle. This would see uranium stocks put back into enrichment and fuel fabrication and plutonium used as a input to mixed-oxide fuel (MOX). Depending on future uranium prices, this cost cost between GBP900 million and GBP4.1 billion ($1.8-8.3 billion).
However, all the options involve a number of assumptions which meant few firm conclusions could be made. In particular, the option to reprocess and recycle would require a 20-year life extension (to 2032) for the Thermal Oxide Reproceesing Plant (Thorp) at Sellafield, that the Sellafield MOX plant could be refurbished to greatly increase output, and that the UK would continue to use nuclear power at a capacity of 12 GWe (roughly equivalent to historical levels).

The reports authors said that "the study has highlighted the very large uncertainties in all options, which emphasise that the results are a basis for further study and optioneering rather than a vehicle for drawing conclusions."

By the time the UK's Advanced Gas-cooled Reactors (AGRs) are retired, some 6000 tonnes of heavy metal (tHM) of used nuclear fuel would have been produced.British Energy's Sizewell B pressurized water reactor (PWR) is set toproduce another 1000 tHM. It has already been decided to reprocess allthe used fuel from the Generation-I Magnox reactors, and 1500 tHM ofthe AGR fuel. What happens to Sizewell B's fuel stocks is up to plantowner British Energy. In total, the AGR and PWR fuel contains enough reusable material to power one 'modern' PWR for a life of 60 years - producing the amount of electricity the UK uses in one year.

Further information

Nuclear Decommissioning Authority

WNA's Nuclear Power in the United Kingdom information paper