“Saying that nuclear power can solve global warming by itself is way over the top”.
— Senior IAEA energy analyst Alan McDonald, quoted in The Independent, 28 June, 2004.

Summary: The potential for nuclear power to reduce greenhouse emissions is often overstated. Building 12 reactors in Australia would reduce our emissions by 8% if they replaced coal-fired plants yet reductions ten times as large are required. Doubling global nuclear power output at the expense of coal would reduce emissions by just 5%. In any realistic nuclear expansion scenario, nuclear power makes only a modest contribution to climate change abatement – and then only if we assume that nuclear power displaces fossil fuels.

The Switkowski (2006) report found that even a major nuclear power program in Australia – 25 reactors coming online from 2020 to 2050 – would reduce emissions by a modest 17% relative to business-as-usual (assuming nuclear displaces black coal). The Switkowski report found that 12 reactors coming online from 2025-2050 would reduce emissions by 8% relative to business-as-usual (assuming nuclear displaces black coal).

By extrapolation, a more modest (and realistic) program of six power reactors would reduce Australia’s overall emissions by just 4% if they displaced coal.

All of the above figures are approximately halved if nuclear power displaces gas-fired power plants: 25 reactors would reduce emissions by 8.5%, 12 reactors would reduce emissions by 4% and 6 reactors would reduce emissions by just 2%.

Greenhouse emissions from renewable energy sources vary but are typically similar to nuclear power. Thus, displacing renewables with nuclear power does not generate any reductions in greenhouse emissions whatsoever. If nuclear power displaces those renewable energy sources that are less greenhouse intensive than nuclear power and/or the many energy efficiency measures which are less greenhouse intensive than nuclear power, nuclear power will result in increased greenhouse emissions.

Doubling global nuclear power output by mid-century at the expense of coal would reduce greenhouse emissions by about 5%. (The basis for that calculation is as follows: the Uranium Information Centre claims that a doubling of nuclear power would reduce greenhouse emissions from the power sector by 25% (Hore-Lacy, 2006). But that figure falls to just 7.5% if considering the impact on overall emissions rather than just the power sector as electricity generation accounts for about 30% of global anthropogenic greenhouse emissions (30% of 25% = 7.5%). If we assume that the doubling of nuclear power takes some decades and that global emissions increase by 50%, the overall reduction in greenhouse emissions is just 5%. If global emissions double over the period of time that it takes to double nuclear output, the emissions reduction of 7.5% would be halved to 3.75%.)

A much larger expansion of nuclear power would have a greater impact on greenhouse emissions to the extent that it displaced fossil fuels. But the weapons proliferation risks would also grow. The Intergovernmental Panel on Climate Change maps out a scenario whereby nuclear capacity would grow to about 3,300 gigawatts in 2100 (approximately nine times more than current capacity as at 2010), and the accumulated plutonium inventory would rise to 50-100 thousand tonnes (IPCC, 1995). That amount of plutonium would suffice to build 5−10 million nuclear weapons.

The safeguards challenge is still greater as a result of the practice of plutonium stockpiling. Japan’s plutonium stockpiling, for example, clearly fans proliferation risks and tensions in north-east Asia. Diplomatic cables in 1993 and 1994 from US Ambassadors in Tokyo questioned the rationale for the stockpiling of so much plutonium since it appeared to be economically unjustified. A 1993 diplomatic cable posed these questions: “Can Japan expect that if it embarks on a massive plutonium recycling program that Korea and other nations would not press ahead with reprocessing programs? Would not the perception of Japan’s being awash in plutonium and possessing leading edge rocket technology create anxiety in the region?” (Greenpeace, 1999)

* Greenpeace, 1 September 1999, “Confidential diplomatic documents reveal U.S. proliferation concerns over Japan’s plutonium program”, media release, .
* Hore-Lacy, Ian, 4 May 2006, ‘Nuclear wagon gathers steam’, Courier Mail.
* Intergovernmental Panel on Climate Change, 1995, ‘Climate Change 1995: Impacts, Adaptations and Mitigation of Climate Change: Scientific-Technical Analyses’, Contribution of Working Group II to the Second Assessment of the IPCC, R.Watson, M.Zinyowera, R.Moss (eds), Cambridge University Press: UK.
* Switkowski Report, 2006, .