A new year’s worry…
By Dave Elliott
One clear difference between renewables and nuclear power is that the former do not lead to the production of long-lived radioactive wastes and the associated problems and costs of dealing with them. Also, old wind and solar facilities can be easily removed, whereas nuclear plant decommissioning is complicated, risky and expensive. With a new UK nuclear expansion programme planned, how much will it cost us to eventually clean it up and deal with its wastes?
Hinkley will be the first of the proposed new plants. In June 2016, Andrea Leadsom, then an Energy Minister in DECC (now, of course, also departed) said that it was estimated that the decommissioning and long-term radioactive waste management costs for EDF’s proposed Hinkley 3.2 GW plant will be ‘around £2/MWh of the strike price’ – which has been set at £92.5/MWh, under the Contract for Difference (CfD) subsidy scheme. It’s hard to know how realistic this £2 figure is and exactly what it covers. And it proved worryingly hard to get the full information.
However, now new estimates have emerged for at least part of it: reportedly, the cost of clean up/decommissioning will be between £5.9bn and £7.2bn, with a start in the decades-long dismantling and clean-up programme being made in the 2080s. All being well, this will be the responsibility of the operator, with contingency extras added in to the legal agreement to cover any overshoot. Though who knows if those will be sufficient – all previous decommissioning estimates have proved to be wrong.
What will actually happen to the waste that is produced? On current plans, as outlined by the Nuclear Decommissioning Authority (NDA), spent fuel from Hinkley and any other new nuclear plants that get built, will have to stay stored on-site, or at some other site, until space is available in a proposed final geological disposal site – if it ever gets built. No one knows where the multi-billion pound disposal site will be located: it’s been left up to candidate communities to volunteer to take it (with major financial inducements being on offer – up to £40m), and so far only one area has offered itself, in Cumbria, backed by the local Copeland and Allerdale district councils. However, that was strongly opposed by the wider Cumbria County council. Provocatively, the government then indicated it might give local councils the final say, overriding the higher level body, but so far no decision has emerged.
It can’t be left forever – there is already a large amount of waste to store and more will be on the way as old plants close, and yet more, if and when new plants start up. There is already a problem with finding sites for low-level waste. Some, provocatively, may be dumped in landfill sites around the UK.
Some new interim stores are being built at reactor sites for higher-level wastes, and more would have to be built for the spent fuel from new reactors, if they go ahead. These stores would have to hold the fort for maybe 100 years since, wherever it ends up, the final disposal site will initially be earmarked for ‘legacy’ waste from old and existing plants. The Government’s 2013 ‘Long Term Nuclear Energy Strategy‘, says ‘Current planning assumptions made by the NDA suggest first waste emplacement will take place by 2040 with legacy High Level Waste emplacement beginning around 2075 and disposal of legacy waste estimated to be completed by about 2130’. So only then can the new wastes from the new plants be emplaced – long after they’ve closed and been decommissioned, even given their hoped-for 60-year operating life.
On current plans, the total volume of the high, intermediate and low level wastes produced from the new reactors will be less than with earlier plants, mainly since the spent fuel will not be reprocessed, which is what creates a lot of low and intermediate waste. However, the amount of extra radioactivity produced will be substantial, especially if a high fuel burn-up strategy is adopted to improve the plants’ economics – that involves using more highly enriched fuel, which stays in the reactor longer, generating more energy but becoming more radioactive. Overall, with the current 16 GW programme, the radioactivity of the total waste in the UK could roughly double or maybe treble, depending on burn-up ratios, with high level waste left sitting in fuel ponds at Hinkley and elsewhere round the country for many decades, or being shipped by train or truck to other sites for ‘interim’ storage.
DECC had said that the cost of this ‘interim’ storage will fall on the nuclear generation companies. The £2/MWh element of the strike price cited by DECC for Hinkley will of course only be for the lifetime of the CfD support – 35 years, although the new Hinkley legal agreement extends the so called ‘primary period’ to 37 years. After that period, the agreement document admits that ‘the Operator will be dependent on revenues from the market which could be less predictable’, but similar waste costs would still have to be met, into the far future, for Hinkley and other plants, and they presumably would also have to pay their share of the cost of building and running the new final waste repository.
DECC developed a costing framework formula for all this, which was accepted by the EU, but it is very open ended on waste: the final UK waste transfer price to be charged to plant operators ‘will be determined only when most of the currently unknown cost factors of the disposal facility have become clear (around 30 years after the start of electricity generation by the nuclear power operator)’. Operators must set aside enough income to meet this charge. Whatever it is, it will be passed on to consumers but, if the company defaults or disappears (EDF is looking very stretched just now!), it will fall on the taxpayer.
So although DECC has said ‘developers will have to prove that they can meet their waste and decommissioning costs in the future and there are publicly available documents setting out how this will happen’, final details are a little vague, with wide cost estimate ranges and various contingency margins and responsibility caps and limitations being built into the agreement. In the case of Hinkley, the government’s ‘Nuclear Waste Transfer Pricing Methodology Notification Paper’ states that ‘unlimited exposure to risks relating to the costs of disposing of their waste in a GDF [geological disposal facility], could not be accepted by the operator as they would prevent the operator from securing the finance necessary to undertake the project’. Instead it says that there will be a ‘cap on the liability of the operator of the nuclear power station which would apply in a worst-case scenario’. It adds: ‘The UK government accepts that, in setting a cap, the residual risk, of the very worst-case scenarios where actual cost might exceed the cap, is being borne by the government.’ Separate documents confirm that the cap also applies should the cost of decommissioning the reactor at the end of its life balloon. In return for the cap, the document says that Hinkley’s operator will pay the government a ‘risk fee’ which ‘is expected to be relatively low, reflecting the high level of confidence that the cap will not be breached’. But, as ever, it will be the taxpayer that meets any excess.
Basically, things could go wrong and we don’t really know what the costs will be so far ahead or, indeed, who will be around to meet them. What we do know is that the wastes will be around – for many generations into the far future. And if, as some want, the UK aims for 75GW of nuclear by 2050, there would be 87,000 tonnes of spent fuel to store, assuming no reprocessing.
Some of the cost of all this could be clawed back if the more than 100 tonnes of plutonium already extracted from UK spent fuel, or any extracted from new wastes, was used to make new fuel. However, there are no firm plans yet, and even being optimistic, the NDA says that, at the earliest, it doesn’t see ‘bulk reuse of plutonium’ as likely to commence until ‘around 2030-2035’.
It is also conceivable that some of the other wastes could be burnt up or transmuted into less long-lived forms if suitable new nuclear technology was developed, but that’s uncertain with unknown costs and risks. The reality is that we are stuck with the wastes for the foreseeable future. Beyond the direct costs, that raises a range of ethical issues, not least should we add to the problem by producing yet more: see Andy Blowers’ new book ‘The Legacy of Nuclear Power’ (Taylor and Francis).