CHAPTER 3: The role of nuclear in the energy portfolio up to 2050 and beyond
38. In 2010, nuclear energy contributed about 16% to the UK‘s electricity supply, from around 12 GW of capacity. Gas-fired generation accounted for 47% of total supply, coal-fired 28%, wind 3%, oil 1% and 5% came from other sources. Attempts have been made to develop scenarios which model the UK’s future energy portfolio on the basis of different levels of nuclear capacity up to 2050 and beyond, the majority focusing on the period up to 2050. The ERP report summarises the various scenarios.
39. We received a range of evidence about the role that nuclear could play within the energy portfolio. All future scenarios have consequences for the rest of the portfolio. Professor Ekins told us, for example, that it is “quite possible to have the amount of electricity that we both want and need, low-carbon, by 2050 without nuclear” by pursuing other low-carbon options, particularly energy efficiency. Dr Douglas Parr, Chief Scientist at Greenpeace UK, shared this view.
42. The ERP report suggests that, realistically, “between 12-38 GW of installed [nuclear] capacity will be required” to achieve a secure, reliable and low-carbon energy system in 2050, with 12 GW likely to be the minimum amount of nuclear generating capacity needed (see Box 2 for an overview of some of the scenarios presented in the report). Given however that the UK’s nuclear capacity is currently around 12 GW it is not clear to us how adopting the minimum 12 GW pathway would enable the UK to meet the target of reducing greenhouse gas emissions by 80% (from 1990 levels) by 2050, without a dramatic increase in the contribution of renewable sources and CCS (particularly since the Government intend to electrify the transport sector over this period, which currently accounts for 37% of primary energy consumption in the UK).
Dame Sue Ion, Chair of the Euratom Science and Technology Committee for the European Commission, agreed. She told us that:
“various studies that have been done … have said that the mathematics and the engineering do not add up [for 12 GW of nuclear energy]; … you need closer to 40 GW in order to stand even a fighting chance [of meeting the UK’s greenhouse gas reduction targets], even then with a very significant reduction in demand of the order of 26% to 30%”.
44. Some experts suggest that 12 GW of energy generation is the minimum contribution that nuclear could make to the energy portfolio up to 2050. However, the weight of evidence indicates that a significantly higher contribution of around 22-38 GW is likely to be required to enable early decarbonisation of the sector before 2030 and to meet the UK’s long-term greenhouse gas emission targets up to 2050 and beyond.
45. The Government should now put in place plans which provide for a range of contributions from nuclear energy to the overall energy portfolio—from low to high—to meet the UK’s future energy needs up to 2050 and beyond. These plans should ensure that the UK has adequate R&D capabilities and associated expertise to keep the option of a higher nuclear energy contribution to the energy portfolio open and recognise that maintaining sufficient capabilities and suitably trained people will require a long lead time.
47. Nuclear energy generation, to a greater or lesser extent, will be an important part of the UK’s energy portfolio up to 2050 and beyond. That much is clear. Less certain is which of the different nuclear technologies will be most effective in providing this capacity. This will depend, in part, on the point at which the supply of uranium begins to operate as a cost driver or constraint on the sector.
49. There are also uncertainties about the rate of development of advanced nuclear reactor technologies, many of which have yet to be demonstrated. (We consider the implications of this uncertain picture for the assessment of our future nuclear R&D needs and associated expertise in Chapter 5 below.)
|There are three categories of fuel cycle, which differ depending on the number of times and manner in which the uranium and plutonium in the spent fuel is recycled.Open fuel cycleThis is also referred to as “once-through” because the fuel passes through a reactor only once, after which it is disposed of without chemical processing. Currently, with uranium being relatively abundant, most countries rely exclusively on a once-through fuel cycle. However, only 3-5% of the original uranium is consumed if the fuel is used in this way.Closed fuel cyclesIn this case the used nuclear fuel is recycled multiple times to improve fuel utilization and reduce the long-term waste burden. After fuel has been in a reactor, the remaining uranium, plutonium and other transuranic elementsare chemically separated from the fission products—that is, the fuel is reprocessed. A closed cycle will generally involve the use of a fast reactor. In this case a very high proportion of the uranium can be utilized (70-90%). France, Japan and Russia employ a closed fuel cycle in certain nuclear facilities.Modified open fuel cycleThis involves a limited number of separation steps, conventional reactors and ideally the uranium, plutonium and transuranic elements remain together in order to lower proliferation risks—if the plutonium is not separated it cannot be weaponised. While not all the uranium is used, substantially more (6-12%) is used than in the open fuel cycle.|