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The Contributions and Challenges of Nuclear Energy

By Trevor Findlay, The Norman Paterson School of International Affairs, Carleton University

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One of the arguments increasingly used to promote nuclear power is the need to tackle climate change. The British government, in laying out the case for ‘new build’ in the United Kingdom, has used this justification the most explicitly

One of the arguments increasingly used to promote nuclear power is the need to tackle climate change. The British government, in laying out the case for ‘new build’ in the United Kingdom, has used this justification the most explicitly

of any government: “Set against the challenges of climate change and security of supply, the evidence in support of new nuclear power stations is compelling.” Some ‘Greens’, notably the founding member of Greenpeace Patrick Moore and British scientist James Lovelock, have been converted to a pro-nuclear stance on the grounds that climate change is so potentially catastrophic that all means to reduce greenhouse gases must be used. Pro-nuclear energy non-governmental organisations (NGOs) have emerged to campaign for increased use of nuclear energy, such as Environmentalists for Nuclear Energy and the US-based Clean and Safe Energy Coalition.

Nuclear power, like hydropower and other renewable energy sources, produces virtually no carbon dioxide directly. Nuclear Energy Outlook notes that fossil fuel sources used in uranium mining, construction and transport indirectly produce an “extremely small amount” of carbon dioxide. The generation of nuclear electricity does, however, emit carbon by using electricity from the grid for fuel fabrication, the operation of nuclear power plants themselves and in other aspects of the nuclear fuel cycle, especially enrichment and reprocessing. It is not, therefore, entirely carbon-free.

To date the international climate change regime has not favoured nuclear energy. Under the Kyoto Protocol states may use nuclear power to help meet their greenhouse emission targets, but may not build nuclear power plants in developing countries in order to obtain certified emissions credits under the Clean Development Mechanism. This was due to strong opposition to nuclear energy from influential state parties on the grounds of sustainability, safety, waste disposal and weapons proliferation.

Although the December 2009 Copenhagen climate conference failed to agree on a new regime, one will likely emerge that includes deeper mandated emission cuts, the involvement of a broader range of states in such cuts and, potentially, a global carbon cap-and-trade system (accompanied in some states by a carbon tax). The latter would be favourable to nuclear energy. Nuclear energy may even find greater official encouragement in a new climate change treaty, due to the growing urgency of tackling climate change. Changes in the attitude of some key governments about nuclear power, such as Italy, Sweden and the UK, may help propel this.

The Intergovernmental Panel on Climate Change (IPCC) has meanwhile reached the startling conclusion that to stabilise global temperatures at 2°C above preindustrial levels would require greenhouse emissions to be cut by up to 85 per cent below 2000 levels by 2050. Scenarios devised by international agencies for doing this propose a significant role for nuclear on the grounds that it is one of the few established energy technologies with a low carbon footprint.

A study in the scientific journal Science in 2004 demonstrated how current technologies, including nuclear energy, could help reduce carbon emissions by 7 billion tonnes of carbon per year by 2050 through seven ‘wedges’ of 1 billion tonnes each. The nuclear wedge, 14.5 per cent of the total, would require adding 700 gigawatts of capacity to current capabilities, essentially doubling it, by building about 14 new plants per year. While this is a reasonable rate, the estimates did not consider that virtually all existing reactors will have to be retired by 2050, even if their operating lives are extended to 60 years. Thus 25 new reactors in total would have to be built each year through 2050 to account for retirements.

The International Energy Agency (IEA), in its 2008 Energy Technology Perspectives, suggested that there should be a “substantial shift” to nuclear to permit it to contribute 6 per cent of carbon dioxide savings, considerably lower than the 14.5 per cent wedge, based on the construction of between 24 and 43 1,000 megawatt nuclear power plants each year between now and 2050. The figures differ from the Science wedge analysis because the IEA envisages higher carbon levels by 2050 and more severe cuts in carbon. The IEA implied that not all countries would need to choose nuclear, noting that “flexibility exists for individual countries to choose” a mix of carbon capture and storage (CCS), renewables and nuclear technology. The IEA called for nothing less than an energy revolution, arguing that the market cannot stimulate industry to act swiftly “without clear signals or binding policies from governments”.

IEA recommendations for achieving greenhouse gas targets by 2050 are relevant as a driver of interest in nuclear energy, but industry must gear up now to sustain the substantial, steady increase envisaged. It would still have to compete with alternative technologies for achieving carbon abatement. The low estimate by the Nuclear Energy Agency (NEA) projects that nuclear will displace only slightly more carbon per year than it does now. This assumes that CCS and renewable technologies are successful, “experience with new nuclear technology is disappointing” and that public opposition to nuclear power continues. The NEA’s high scenario projects almost 5 gigatonnes of carbon displacement and assumes a positive experience with “a high degree of public acceptance of nuclear power”. A 2003 study by the Massachusetts Institute of Technology (MIT) estimated that a three-fold expansion of nuclear generating capacity by 2050 would avoid about 25 per cent of the increment in carbon emissions otherwise expected in a business-as-usual scenario.

These hedged scenarios reveal that the barriers to nuclear contributing significantly to meeting targets for reducing greenhouse gases are both technological and political. Opinions differ as to how high these barriers are. Members of the 2007 Keystone Nuclear Power Joint Fact-Finding Dialogue, a broad range of stakeholders, reached no consensus on the likely rate of expansion of nuclear power over the next 50 years in filling a substantial portion of its assigned carbon wedge. The MIT study recommended changes in government policy and industrial practices needed in the near term, but in a 2009 review of its earlier report despaired at the lack of progress.

On the political side, there appears to be consensus that a business-as-usual approach to nuclear energy will not increase its contribution to tackling climate change. Nuclear’s long lead times (reactors take up to ten years to plan and build) and large up-front costs mean that without a determined effort by governments by 2030 nuclear would have little impact in reducing greenhouse gas emissions. Even replacing the existing nuclear fleet to maintain the current contribution to avoiding greenhouse gases will require a major undertaking. Despite the rhetoric, there is scant evidence that governments are taking climate change seriously enough to effect the energy revolution that the IEA has called for, much less implementing policies that would promote nuclear energy as a growing part of the solution.

Even if carbon taxes or emissions trading schemes help level the economic playing field by penalising electricity producers that emit more carbon, these measures are likely to take years to establish and achieve results. They will also benefit, probably disproportionately, cheaper and more flexible low- or non-carbon emitting technologies such as renewables, solar and wind. And they make conservation and efficiency measures more attractive.

One argument for using nuclear to tackle climate change is that the problem is so potentially catastrophic that every means possible should be used, regardless of cost. However, resources for tackling climate change are not unlimited. Already governments and publics baulk at the estimated costs. Therefore, the question becomes what are the most economical means for reducing a given amount of carbon. One answer is to examine the financial cost of reducing coal-fired carbon emissions through various alternative means of generating electricity.

Runaway global warning may become more apparent and politically salient through a catastrophic event such as a sudden halt to the North Atlantic sea current, or the disappearance of all summer ice from the North Pole. A growing number of climatologists have concluded that the IPCC underestimated both the scale and pace of global warming, notably changes in the Arctic ice sheet and sea levels. Some say the situation is so dire that the business of burning coal should be shut down by 2030, if not much sooner. In such circumstances, massive industrial mobilisation to build nuclear power plants rapidly may be politically and technologically desirable.

But nuclear power would still face numerous barriers in responding to such a catastrophe. Large-scale expansion of nuclear energy is simply too slow and too inflexible compared to the alternatives, if reductions in carbon emissions must be made by as early as 2015. As the Keystone report noted, just to build enough nuclear capacity to achieve the carbon reductions of a wedge would require an immediate return to rapid growth as in the 1980s and ’90s sustained for 50 years.

There is also the vast amounts of water that nuclear reactors normally need for cooling purposes. If climate change reduces river flow or results in warmer water, new nuclear power plants will have to be located on sea coasts. Plant costs can reportedly change by $1 billion depending on whether a plant is cooled by saltwater or freshwater. Plants already using river water may be forced to close or require costly changes to avoid overheating water that is to be discharged back into increasingly warm rivers. France has already been forced to shut down certain reactors during heat waves for this reason. The Indian Point reactor in upstate New York is currently facing closure unless it undergoes expensive modifications to avoid its discharge killing thousands of fish in the Hudson River every year.

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