Professor Geoffrey Hammond is Professor of Mechanical Engineering and Director of the interdisciplinary International Centre for the Environment at the University of Bath.
Britain faces major challenges in the period out to 2050. Socio-technical solutions will be required on both the demand and supply side of any future UK energy system. Reduction in the energy demand for heat, power and transport will be a significant element of any energy strategy aimed at limiting global warming to <2°C under whatever pathways we take towards our mid-century goals.
Improvements in energy efficiency can be obtained from better thermal insulation of the building fabric, smart appliances and controls, alongside the adoption of efficient heating systems, such as heat pumps, community energy schemes, and the like. In addition, lifestyle or workplace changes may well be needed – but these will be partially offset by so-called ‘rebound effects’. Decarbonising the supply side is likely to see the continued adoption of offshore wind and rooftop solar photovoltaic (PV) arrays. It will inevitably need the uptake of carbon capture and storage (CCS) coupled to gas-fired power plants for a cost-efficient transition, together with sustainable bioenergy and biofuels, and possibly hydrogen as a fuel and energy storage media in the long-term. Unfortunately, there are constraints over the use of bioenergy resources, including uncertainties over the availability of sustainably-sourced biomass in the UK, land use challenges, and competition with food supply.
The energy infrastructure in Britain will also need renewal in order to make it more resilient (to climate change impacts, for example) and to potentially accommodate greater decentralised or distributed generation, including greater use of both large and small energy storage devices. Significant generation, transmission and distribution network reinforcements (operating with much lower utilisation factors) will be needed to meet future changes in demand and generation patterns. However, smart power innovations (a combination of interconnectors, storage and ‘demand flexibility’) could generate £8bn per year in savings. The electricity grid is arguably the most vulnerable part of the power system, reinforcing the case for UK network renewal and reconfiguration by the middle of the 21st Century. Innovation, systems integration, and ‘whole systems’ thinking to identify sustainable energy options (sometimes termed ‘optionality’ in industry) will therefore be critically important in the transition towards a low-carbon future.
Successive UK Governments since the 1990s have argued that new nuclear power plants have an important role to play in our energy mix. The decision by the UK Government to instigate a pause and review before signing off on the contract for the construction of the Hinkley Point C Nuclear Power Station may well be sensible, or even courageous in terms of the diplomatic implications. All energy technologies have unwanted side-effects, including the likes of shale gas extraction (via hydraulic fracturing or 'fracking') and renewables. They vary only in their magnitude and the extent to which they impact on different human communities and natural ecosystems. Fossil fuels give rise to significant quantities of carbon dioxide emissions that are likely to lead to yet further global warming. Wind generators, in contrast, are low carbon but require costly back-up capacity (most likely from natural gas combined cycle power plants) at high concentrations when wind speeds are low. Indeed, even building energy-saving measures on the demand side can have adverse social consequences – the switch of the burden of financing from the large energy utilities to potentially poor consumers, for example, for the installation of modern condensing boilers, thermal insulation, heating controls, or micro-generators.
The real nuclear power ‘balance sheet’ has therefore both credit and debit sides. On the positive front, it represents a low- or near-zero-carbon source of electricity that is available on a large-scale. However, there are potential risks in terms of nuclear plant safety; actual failures in the case of the Windscale fire at the military plutonium facility in Cumbria (1957), the Three Mile Island partial ‘meltdown’ in Pennsylvania that was contained (1979), and Chernobyl meltdown – that was not – in what is now the Ukraine (1986). In the vicinity of Three Mile Island over 630,000 local people self-evacuated the area following the accident. Closer to home, the Irish Government and NGOs have long been concerned about the cumulative impact of low-level radioactive emissions, principally from the Sellafield nuclear fuel reprocessing and medium-term storage facility, into the Irish Sea.
Perhaps the most dramatic side-effect of power generation was demonstrated by the nuclear power reactor failure at the Fukushima Daiichi site on the North East coast of Japan in March 2011. That was caused by a tsunami wave of sea water some 14 metres high, and triggered by a magnitude 8.2 earthquake. The plant was built to withstand a wave of only about 6 metres. This was arguably a so-called ‘Black Swan’ event – one that is very unlikely to occur but, when it does, the impact is extremely severe. They may be instigated by natural causes as at Fukushima, although the failure to allow for or respond to them results from human frailties. That has induced major changes in energy policy around the world, particularly the potential shut-down of the programme in Germany and the shift in Japanese public sentiment that has been calling for their nuclear power programme to be abandoned.
The case is often made in the UK for nuclear power generation on the grounds of climate change mitigation. But even a doubling of Britain’s nuclear capacity over the next 30 years would only yield about an 8% cut in CO2 emissions. The Hinkley Point C station would also provide 7% of our electricity under favourable baseload conditions. Nuclear power plant safety and radioactive emissions from a European pressurised reactor, such as that planned for Hinkley, are unlikely to present any significant concern in a UK context because of our tight regulatory regime. Nevertheless, the subsequent treatment of nuclear waste and the high life-cycle costs, when 'back-end' (decommissioning and waste disposal/storage) costs are taken into account, are important downsides. Friends of the Earth and Greenpeace have argued that nuclear power is one of the least cost-competitive means of carbon abatement. An energy-efficiency strategy, for example, displaces between 2.5 and 20 times more CO2 emissions than nuclear power per dollar (euro or pound) invested. They will fall disproportionately on different sections of British society.
It has been speculated in the press that the new UK Government’s pause of the Hinkley Point C decision is primarily due to a long-term concern by the Prime Minister (Theresa May) on security concerns regarding the involvement of the Chinese. The state-owned China General Nuclear Power Corporation was due to fund a third of the cost of this European pressurised reactor, with the French energy utility eDF covering the bulk of the investment. It is currently estimated by the French to cost £80bn to build over 10 years, although the UK National Audit Office believes that this could cost British consumers over £30bn per annum to run in terms of top-up payments. Apparently the former Chancellor of the Exchequer, George Osborne, rejected the idea of a "special share" in the Somerset-based Hinkley Point C nuclear power project in order to provide extra protection against potential Chinese national security threats. No European pressurised reactor design has actually been commissioned anywhere in Europe, and those elsewhere are some 10 years behind schedule and way over projected construction costs. Taking time to consider the various negative consequences of this proposal is therefore likely to be time (and money) well spent.