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Fukushima and beyond: nuclear power in a low-carbon world

Nuclear Monitor Issue: 
Peter Karamoskos − Nuclear Radiologist, member of the National Council of the Medical Association for Prevention of War (Australia)

Review of: Christopher Hubbard, 2014, 'Fukushima and beyond: nuclear power in a low-carbon world', Ashgate Publishing, ISBN 978-1-4094-5491-5

When Tony Benn was Britain's Energy Secretary, he warned about people who came to you with a problem in one hand, and a solution in their back pocket. He learnt this from Britain's nuclear industry. One should keep this in mind when considering climate change as the latest rationale for expansion of the nuclear industry.

This book, authored by a lecturer in International Relations and International Security at Edith Cowan University in Perth, Australia, is rooted in the premise that nuclear power is essential to climate change mitigation.

The Fukushima nuclear disaster is used as a contextual leverage point to argue the counterfactual that this event, and more particularly the response to it, has made nuclear power more desirable than he contends it previously was. As the author states, rather blithely, on the issue of safety, "... simply put, the nuclear energy sector is extremely safe because it must be."

The foundational premise of the book, that nuclear power is essential to climate change mitigation is axiomatic to all arguments which follow. If it is not, then nuclear power becomes nothing more than a 'climate choice'.

The problem with this premise, which the author does not challenge, is that if we only address greenhouse gas emissions from electricity generation, then we can't avert climate change. Indeed, an important point not stated until the last chapter is that electricity does not account for the majority of greenhouse gas emissions, yet, this is the only sector that nuclear power can influence.

The latest IPCC Report1 states that the latest global greenhouse gas emissions were 49 gigatonnes (Gt) CO2-eq/yr as of 2010. Electricity and heating accounted for 12 Gt, with electricity alone about 9 Gt. Agriculture, forestry and other land use account for 12 Gt, transport 7 Gt, industry 10 Gt. Other energy sources account for the balance. So, approximately 80% of greenhouse gases (GHG) have nothing to do with electricity.

We need to reduce our GHG emissions by 40–70% of 2010 emissions by 2050 and near-zero emissions by the end of this century if we are to maintain a global temperature rise of <2 °C and thus avoid distressing climate change impacts in ecological and socio-economic systems.

If we assume the (incorrect) argument that nuclear power produces no CO2 emissions and that every kW produced avoids 500 g of CO2-e/kWh being released into the atmosphere (the average carbon intensity of global electricity generation), nuclear power currently abates 1.5 Gt per annum of GHG.

The IAEA in a report advocating nuclear power as a solution to climate change, forecasts two scenarios for the future of nuclear power: a 'low' scenario (435 GW), and a 'high' scenario (722 GW) generation capacity by 2030. However, the claim that the nuclear industry will more than double its capacity over the next few decades (in the 'high scenario') is pure fantasy.

We currently commission about one new reactor a year somewhere in the world. If under the most optimistic conditions we raise that to 8 a year for the next 10 years and 15 a year for the 10 years after that, we simply have replaced the reactors that will be de-commissioned by then. And for every year we do not meet this rate of build, the hill to be climbed gets steeper.

However, assuming that the nuclear industry pulled the proverbial rabbit out of a hat and was able to double its capacity over this time period, and (falsely) assuming that it generates no greenhouse gases itself, it would only abate an additional 2 billion tonnes of greenhouse gases per annum over the existing 1.5 Gt it already abates, i.e. 4% abatement on 2010 emissions. Therefore, how can a 3.6 Gt abatement (assuming it replaces mainly fossil fuels for electricity generation and it does not generate GHG in its life cycle – clearly not the case) be considered indispensable?

Surely it can be readily and quickly replaced with renewables, which can also address several of the other non-electricity GHG-emitting sectors. In 2013 alone, the world brought online 69 GW of solar PV and wind capacity.

If simple arithmetic escapes Hubbard's sanguine assertions as to the desirability and indispensability of nuclear power, also missing from his treatise is consideration of the blatant evidence of nuclear power being in long-term decline – long before Fukushima. The nuclear share of the world's electricity generation has declined steadily from a historic peak of 17.6% in 1996 to 10.8% in 2013.

Nuclear power and renewables in China

Even in China, which has the most ambitious nuclear power programme in the world and is the poster child for nuclear boosters, including Prof. Hubbard, more renewable electricity capacity was brought online than nuclear and fossil fuels combined in 2013. This is also reflected in a new assessment by the OECD's International Energy Agency. During 2000–2013, global investment in power plants was split between renewables (57%), fossil fuels (40%) and nuclear power (3%).

China set the world record for solar PV implementation in one year at 12 GW (compared with 3 GW for nuclear) and as of the end of 2013 has more solar PV capacity than nuclear, and five times more wind power than nuclear – and the gap between renewables and nuclear in China keeps increasing. China sees electricity generation capacity as a portfolio enterprise and is clearly putting vastly more bets on renewables than nuclear – as is the rest of the world. China's plan is for 58 GW of nuclear capacity by 2020, but wind alone already exceeded this capacity last year.

Hubbard uses optimistic projections of 300–500 GW nuclear capacity in China by 2050, but doesn't divulge that these have been promoted by the industry itself and have not been approved by the government and are certainly not government policy.

Furthermore, rapid technological advances are also making low-carbon alternatives to nuclear power appear more attractive. Bloomberg New Energy Finance, an industry publisher, forecasts that onshore wind will be the cheapest way to make electricity in China by 2030.

Nuclear output accounts for only 4.4% of global energy consumption, the smallest share since 1984. Renewable energy, on the other hand, provided an estimated 19% of global final energy consumption in 2012 (electricity, heating, transport) and continued to grow in 2013. Of this total share in 2012, modern renewables accounted for approximately 10%, with the remainder (estimated at just over 9%) coming from traditional biomass. Heat energy from modern renewable sources accounted for an estimated 4.2% of total final energy use; hydropower made up about 3.8% and an estimated 2% was provided by power from wind, solar, geothermal and biomass, as well as by biofuels.

Nuclear safety

Hubbard writes off concerns of nuclear safety in the industry with the circular assertion 'safe because it must be' (although the Fukushima disaster, which he analyses in detail using the excellent independent report of the Japanese Diet which declared the 'myth of nuclear safety', actually contradicts his assertion).

Hubbard insists on using China as an exemplar of nuclear safety, yet his research is wanting. Philippe Jamet, a French nuclear safety commissioner, told his country's parliament earlier last year that Chinese counterparts were 'overwhelmed'. Wang Yi of the Chinese Academy of Social Sciences, an expert body, has warned that there are indeed 'uncertainties' in China's approach to nuclear safety.

Hubbard doesn't even touch on the proliferation hazards of an expansion of the nuclear industry (Iran is clearly an inconvenient truth); waves away nuclear waste disposal problems (science will fix it); and fudges the (increasingly deteriorating) economics of nuclear power (conveniently absent is the fact that private investors haven't put a cent into nuclear power for decades, unlike renewables).

Furthermore, Hubbard's description of new Generation IV and small modular reactors (these apparently will solve all major problems, e.g. waste, proliferation, accidents) might as well be no more than a cut and paste from a nuclear reactor sales brochure, in its lack of any critical appraisal of these fantasy claims. These designs are literally still only on paper with no track record, and won't be implemented for decades – if at all (too bad for GHG abatement).

The UK Government's Nuclear National Laboratories have released several reports stating that purported benefits of these new-generation reactors are at best overstated. Furthermore, proliferation hazards abound from proposals to use up existing plutonium stocks in these reactors (it needs to be converted to the bomb-ready metallic form first). Their safety is also questionable despite claims to the contrary, as their designs contravene the 'Defence in Depth' principles of nuclear safety of most nuclear regulators (most lack proper secondary containment, especially small modular reactors). In other words, they might never be licensed because they are not safe.

The author's forte is not radiation science and it shows. He lacks an understanding of the various world bodies involved in nuclear power and radiation science. This is disappointing for someone who claims expertise in the nuclear sector. For example, the IAEA is not a global regulatory body, as he claims, but an advisory body that member states join to provide guidance on implementation of nuclear activities. It has no legal jurisdiction to investigate or advise any member state without an invitation by the relevant member state.

The IAEA does have teeth to investigate suspected clandestine-prohibited proliferation-sensitive nuclear-cycle activities, but cannot impose itself (Iran is a case in point) without permission – hardly the global cop the author seems to think it is.

It is the member states themselves which regulate their own nuclear activities. This distinction is critical because it means nuclear safety is dependent on member states willingly implementing international best practice, and furthermore, not engaging in clandestine weapons development. However, where there is a lack of transparency and accountability − the two main principles of nuclear safety − safety is compromised. It is noteworthy that the main countries expanding their nuclear industries are those which rank low on Transparency International's Corruption Perceptions Index.

It is difficult to reconcile the author's views with the real world. The author engages in wishful, uncritical, almost magical thinking on a grand scale in its blandishments of the nuclear power industry.

1. IPCC. 2014. "Summary for Policymakers." In Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Edited by C. B. Field et al., pp.1–32.

Abridged from Medicine, Conflict and Survival, March 2015,

An open letter to nuclear lobbyists in response to their open letter to environmentalists

Nuclear Monitor Issue: 
Jim Green − Nuclear Monitor editor

A group of conservation scientists has published an open letter urging environmentalists to reconsider their opposition to nuclear power.1 The letter is an initiative of Australian academics Barry Brook and Corey Bradshaw, and has been endorsed by 69 (other) scientists from Australia, Canada, China, Finland, France, India, Indonesia, Italy, Norway, Singapore, South Africa, Switzerland, the UK, and the US.

The co-signatories "support the broad conclusions drawn in the article 'Key role for nuclear energy in global biodiversity conservation', published in Conservation Biology."2 The open letter states: "Brook and Bradshaw argue that the full gamut of electricity-generation sources − including nuclear power − must be deployed to replace the burning of fossil fuels, if we are to have any chance of mitigating severe climate change."

So, here's my open letter in response to the open letter initiated by Brook and Bradshaw:

Dear conservation scientists,

Space constraints prohibit the usual niceties that accompany open letters so I'll get straight to the point. If you want environmentalists to support nuclear power, get off your backsides and do something about the all-too-obvious problems associated with the technology. Start with the proliferation problem since the multifaceted and repeatedly-demonstrated links between the 'peaceful atom' and nuclear weapons proliferation pose profound risks and greatly trouble environmentalists and many others besides.3

The Brook/Bradshaw journal article (rightly) emphasises the importance of biodiversity − but even a relatively modest exchange of some dozens of nuclear weapons could profoundly effect biodiversity, and large-scale nuclear warfare undoubtedly would.4

As Australian scientist Dr Mark Diesendorf notes: "On top of the perennial challenges of global poverty and injustice, the two biggest threats facing human civilisation in the 21st century are climate change and nuclear war. It would be absurd to respond to one by increasing the risks of the other. Yet that is what nuclear power does."5

The Brook/Bradshaw article ranks power sources according to seven criteria: greenhouse gas emissions, cost, dispatchability, land use, safety (fatalities), solid waste, and radiotoxic waste. WMD proliferation is excluded. By all means ignore lesser concerns to avoid a book-length analysis, but to ignore the link between nuclear power and weapons is disingenuous and the comparative analysis of power sources is a case of rubbish in, rubbish out.

Integral fast reactors

While Brook and Bradshaw exclude WMD proliferation from their comparative assessment of power sources, their journal article does address the topic. They promote the 'integral fast reactor' (IFR) that was the subject of R&D in the US until was abandoned in the 1990s.6 If they existed, IFRs would be metal-fuelled, sodium-cooled, fast neutron reactors.

Brook and Bradshaw write: "The IFR technology in particular also counters one of the principal concerns regarding nuclear expansion − the proliferation of nuclear weapons − because its electrorefining-based fuel-recycling system cannot separate weapons-grade fissile material."

But Brook's claim that IFRs "cannot be used to generate weapons-grade material"7 is false.8 IFR advocate Tom Blees notes that: "IFRs are certainly not the panacea that removes all threat of proliferation, and extracting plutonium from it would require the same sort of techniques as extracting it from spent fuel from light water reactors."9 George Stanford, who worked on an IFR research program in the US, states: "If not properly safeguarded, [countries] could do [with IFRs] what they could do with any other reactor – operate it on a special cycle to produce good quality weapons material."10

The presentation of IFRs by Brook and Bradshaw contrasts sharply with the sober assessments of the UK and US governments. An April 2014 US government report notes that pursuit of IFR technology would be associated with "significant technical risk" and that it would take 18 years to construct an IFR and associated facilities.11 A recent UK government report notes that IFR facilities have not been industrially demonstrated, waste disposal issues remain unresolved, and little can be ascertained about cost.12

Brook and Bradshaw argue that "the large-scale deployment of fast reactor technology would result in all of the nuclear-waste and depleted-uranium stockpiles generated over the last 50 years being consumed as fuel." Seriously? An infinitely more likely outcome would be some fast reactors consuming waste and weapons-useable material while other fast reactors and conventional uranium reactors continue to produce such materials.

The Brook/Bradshaw article ignores the sad reality of fast reactor technology: over US$50 billion (€40.2b) invested, unreliable reactors, numerous fires and other accidents, and one after another country abandoning the technology.13

Moreover, fast reactors have worsened, not lessened, proliferation problems. John Carlson, former Director-General of the Australian Safeguards and Non-proliferation Office, discusses a topical example: "India has a plan to produce such [weapon grade] plutonium in fast breeder reactors for use as driver fuel in thorium reactors. This is problematic on non-proliferation and nuclear security grounds. Pakistan believes the real purpose of the fast breeder program is to produce plutonium for weapons (so this plan raises tensions between the two countries); and transport and use of weapons-grade plutonium in civil reactors presents a serious terrorism risk (weapons-grade material would be a priority target for seizure by terrorists)."14

The fast reactor techno-utopia presented by Brook and Bradshaw is attractive. Back in the real world, there's much more about fast reactors to oppose than to support. And the large-scale deployment of Generation IV reactor technology is further away than they care to admit. The Generation IV International Forum website states: "It will take at least two or three decades before the deployment of commercial Gen IV systems. In the meantime, a number of prototypes will need to be built and operated. The Gen IV concepts currently under investigation are not all on the same timeline and some might not even reach the stage of commercial exploitation."15

Creative accounting and jiggery-pokery

Brook and Bradshaw also counter proliferation concerns with the following argument: "Nuclear power is deployed commercially in countries whose joint energy intensity is such that they collectively constitute 80% of global greenhouse-gas emissions. If one adds to this tally those nations that are actively planning nuclear deployment or already have scientific or medical research reactors, this figure rises to over 90%. As a consequence, displacement of fossil fuels by an expanding nuclear-energy sector would not lead to a large increase in the number of countries with access to nuclear resources and expertise."

The premise is correct − countries operating reactors account for a large majority of greenhouse emissions. But even by the most expansive estimate − Brook's16 − less than one-third of all countries have some sort of weapons capability, either through the operation of reactors or an alliance with a nuclear weapons state. So the conclusion − that nuclear power expansion "would not lead to a large increase in the number of countries with access to nuclear resources and expertise" − is nonsense and one wonders how such jiggery-pokery could find its way into a peer-reviewed journal.

The power−weapons conundrum is neatly summarised by former US Vice-President Al Gore: "For eight years in the White House, every weapons-proliferation problem we dealt with was connected to a civilian reactor program. And if we ever got to the point where we wanted to use nuclear reactors to back out a lot of coal ... then we'd have to put them in so many places we'd run that proliferation risk right off the reasonability scale."17


Apart from the their misinformation about IFRs, and their nonsense argument about the proliferation implications of expanding nuclear power, Brook and Bradshaw add one further comment about proliferation: "Nuclear weapons proliferation is a complex political issue, with or without commercial nuclear power plants, and is under strong international oversight."

Oddly, Brook and Bradshaw cite a book by IFR advocate Tom Blees in support of that statement.18 But Blees argues for the establishment of an international strike force on full standby to attend promptly to any detected attempts to misuse or to divert nuclear materials (p.269). That is a far cry from the International Atomic Energy Agency's safeguards system. In articles and speeches during his tenure as the Director General of the IAEA from 1997−2009, Dr. Mohamed ElBaradei said that the Agency's basic rights of inspection are "fairly limited", that the safeguards system suffers from "vulnerabilities" and "clearly needs reinforcement", that efforts to improve the system have been "half-hearted", and that the safeguards system operates on a "shoestring budget ... comparable to that of a local police department".

Moreover, Blees argues that: "Privatized nuclear power should be outlawed worldwide, with complete international control of not only the entire fuel cycle but also the engineering, construction, and operation of all nuclear power plants. Only in this way will safety and proliferation issues be satisfactorily dealt with. Anything short of that opens up a Pandora's box of inevitable problems." (p.303)

Blees doesn't argue that the nuclear industry is subject to strong international oversight − he argues that "fissile material should all be subject to rigorous international oversight" (emphasis added).19

Of course, the flaws in the nuclear safeguards system are not set in stone.20 And this gets me back to my original point: if nuclear lobbyists want environmentalists to support nuclear power, they need to get off their backsides and do something about the all-too-obvious problems such as the inadequate safeguards system. Environmentalists have a long record of working on these problems and the lack of support from nuclear lobbyists has not gone unnoticed.

To give an example of a topical point of intervention, Canada has agreed to supply uranium and nuclear technology to India with greatly reduced safeguards and non-proliferation standards, Australia seems likely to follow suit, and those precedents will likely lead to a broader weakening of international safeguards (and make it that much more difficult for nuclear lobbyists to win support from environmentalists and others). The seriousness of the problem has been acknowledged by, among others, a former Chair of the IAEA Board of Governors21 and a former Director-General of the Australian Safeguards and Non-proliferation Office.14 It is a live debate in numerous nuclear exporting countries and there isn't a moment to lose.

Nuclear lobbyists should join environmentalists in campaigning for a strengthening of the safeguards system and against efforts to weaken the system. But Brook and Bradshaw have never made even the slightest contribution to efforts to strengthen safeguards, and it's a safe bet that the same could be said of the other signatories to their open letter.

To mention just one more point of intervention, the separation and stockpiling of plutonium from power reactor spent fuel increases proliferation risks. There is virtually no demand for the uranium or plutonium separated at reprocessing plants, and no repositories for the high-level waste stream. Yet reprocessing continues, the global stockpile of separated plutonium increases year after year and now stands at around 260 tons.22 It's a problem that needs to be solved; it's a problem that can be solved.

Endorsing the wishful thinking and misinformation presented in the Brook/Bradshaw journal article is no substitute for an honest acknowledgement of the proliferation problems associated with nuclear power, coupled with serious, sustained efforts to solve those problems.


1. 15 Dec 2014, 'An Open Letter to Environmentalists on Nuclear Energy',
2. Brook, B. W., and C. J. A. Bradshaw. 2014. Key role for nuclear energy in global biodiversity conservation. Conservation Biology.
5. Dr Mark Diesendorf, University of NSW, 'Need energy? Forget nuclear and go natural', 14 Oct 2009,
7. Barry Brook, 9 June 2009, 'Nuking green myths', The Australian,
11. US Department of Energy, April 2014, 'Report of the Plutonium Disposition Working Group: Analysis of Surplus  Weapon‐Grade Plutonium Disposition Options',
See also 'Generation IV reactor R&D',
12. UK Nuclear Decommissioning Authority, January 2014, 'Progress on approaches to the management of separated plutonium – Position Paper',
See also: 'Will PRISM solve the UK's plutonium problem?',
13. International Panel on Fissile Materials, 2010, 'Fast Breeder Reactor Programs: History and Status',
17. David Roberts, 10 May 2006, 'An interview with accidental movie star Al Gore',
18. Blees T. 2008. 'Prescription for the planet: the painless remedy for our energy & environmental crises'. BookSurge, Charleston, South Carolina.
22. Fissile Materials Working Group, 6 May 2013, 'How do you solve a problem like plutonium?',

International Energy Agency's 'World Energy Outlook'

Nuclear Monitor Issue: 

The International Energy Agency (IEA) − a self-described autonomous organisation with 29 member countries − has released its latest World Energy Outlook (WEO) report.1

In the central scenario of WEO, world primary energy demand is 37% higher in 2040 compared to 2013, and energy supply is divided into four almost equal parts: low-carbon sources (nuclear and renewables), oil, natural gas and coal. Electricity is projected to be the fastest-growing final form of energy − WEO states that 7,200 gigawatts (GW) of power capacity needs to be built by 2040. Global investment in the power sector amounts to US$21 trillion (€16.8t), with over 40% in transmission and distribution networks. CO2 emissions from the power sector rise from 13.2 gigatonnes (Gt) in 2012 to 15.4 Gt in 2040, maintaining a share of around 40% of global emissions over the period. Fossil fuels continue to dominate the power sector, but their share of generation declines from 68% in 2012 to 55% in 2040.

Nuclear growth?

WEO notes that nuclear power accounts for 11% of global electricity generation, down from a peak of almost 18% in 1996. There is "no nuclear renaissance in sight" according to the IEA. In the WEO 'Low Nuclear Case', global nuclear capacity drops by 7% between 2013 and 2040. In the 'New Policies Scenario', nuclear capacity rises by 60% to 624 GW. This is the net result of 380 GW of capacity additions and 148 GW of retirements. Just four countries account for most of the projected nuclear growth in the 'New Policies Scenario': China (132 GW increase), India (33 GW), South Korea (28 GW) and Russia (19 GW). Generation increases by 16% in the US, rebounds in Japan (although not to the levels prior to the accident at Fukushima Daiichi) and falls by 10% in the European Union. The number of countries operating power reactors increases from 31 in 2013 to 36 in 2040. Needless to say, the projected growth in the New Policies Scenario is speculative and unlikely. Historically, low projections from bodies such as the IEA and the IAEA tend to be more accurate than high projections.2

WEO states that nuclear growth will be "concentrated in markets where electricity is supplied at regulated prices, utilities have state backing or governments act to facilitate private investment." Conversely, "nuclear power faces major challenges in competitive markets where there are significant market and regulatory risks, and public acceptance remains a critical issue worldwide."3 More than 80% of current nuclear capacity is in OECD countries but this falls to 52% in 2040 in the New Policies Scenario. Of the 76 GW presently under construction, more than three-quarters is in non-OECD countries.

A wave of reactor retirements

WEO states: "A wave of retirements of ageing nuclear reactors is approaching: almost 200 of the 434 reactors operating at the end of 2013 are retired in the period to 2040, with the vast majority in the European Union, the United States, Russia and Japan." WEO estimates the cost of decommissioning reactors to be more than US$100 billion (€80b) up to 2040. The report notes that "considerable uncertainties remain about these costs, reflecting the relatively limited experience to date in dismantling and decontaminating reactors and restoring sites for other uses." IEA chief economist Fatih Birol said: "Decommissioning of those power plants is a major challenge for all of us – for the countries that are pursuing nuclear power policies and for those who want to phase out their nuclear power plants. Worldwide, we do not have much experience and I am afraid we are not well-prepared in terms of policies and funds which are devoted to decommissioning. A major concern for all of us is how we are going to deal with this massive surge in retirements in nuclear power plants."4

Paul Dorfman of the Energy Institute at University College London noted that the US$100bn figure is only for decommissioning and does not include the costs of permanent waste disposal. "The UK's own decommissioning and waste disposal costs are £85bn alone, so that gives you an idea of the astronomical costs associated with nuclear," he said.5

Nuclear safety, waste and weapons

WEO notes: "Public concerns about nuclear power must be heard and addressed. Recent experience has shown how public views on nuclear power can quickly shift and play a determining role in its future in some markets. Safety is the dominant concern, particularly in relation to operating reactors, managing radioactive waste and preventing the proliferation of nuclear weapons. Confidence in the competence and independence of regulatory oversight is essential ..." In the WEO high-growth New Policies Scenario, the cumulative amount of spent nuclear fuel that has been generated more than doubles, reaching 705,000 tonnes in 2040. The report notes that no country has yet established permanent facilities for the disposal of high-level radioactive waste from commercial reactors.

Nuclear power and climate change

WEO states that nuclear power "has avoided the release of an estimated 56 gigatonnes of CO2 since 1971, or close to two years of emissions at current rates." The claim is meaningless without a point of reference. Presumably the calculation is based on the arbitrary assumption that all nuclear power generation displaces generation from coal-fired power plants.

Renewable electricity generation

The share of renewables in total power generation rises from 21% in 2012 to 33% in 2040 in the New Policies Scenario, and renewables account for nearly half of new capacity. Renewable electricity generation nearly triples between 2012 and 2040, overtaking gas as the second-largest source of generation in the next couple of years and surpassing coal after 2035. China sees the largest increase in generation from renewables, more than the gains in the EU, US and Japan combined. Wind power accounts for the largest share of growth in renewables-based generation (34%), followed by hydropower (30%) and solar (18%). Biofuels use more than triples. Advanced biofuels, which help address sustainability concerns about conventional biofuels, gain market share after 2020, making up almost 20% of biofuels supply in 2040. Global subsidies for renewables amounted to US$121 billion (€97b) in 2013 and are anticipated to increase to nearly US$230 billion (€184b) in 2030 in the New Policies Scenario, before falling to $205 billion (€164b) in 2040. In 2013, almost 70% of subsidies to renewables for power were provided in just five countries: Germany, the US, Italy, Spain and China.

Fossil-fuel subsidies totalled $550 billion (€439b) in 2013 – 4.5 times greater than subsidies for renewables – and are holding back investment in efficiency and renewables. For example, in the Middle East, nearly 2 mb/d of crude oil and oil products are used to generate electricity when, in the absence of subsidies, renewables would be competitive with oil-fired power plants. Energy efficiency slows energy demand growth. Without the cumulative impact of energy efficiency measures, oil demand in 2040 would be 22% higher, gas demand 17% higher and coal demand 15% higher.


2. See for example tables 33 and 34, p.56,

Climate change, water and energy

Nuclear Monitor Issue: 

A July 2013 report by the US Department of Energy details many of the interconnections between climate change and energy.[1] These include:

  • Increasing risk of shutdowns at coal, gas and nuclear plants due to decreased water availability which affects cooling at thermoelectric power plants, a requirement for operation;
  • Higher risks to energy infrastructure located along the coasts due to sea level rise, the increasing intensity of storms, and higher storm surge and flooding. A 2011 study evaluated the flood risk from coastal storms and hurricanes for the Calvert Cliffs nuclear plant (Maryland) and the Turkey Point nuclear plant (Florida). Under current conditions, storm surge would range from 0.6 metres for a Nor'easter to 3.7 metres for a Category 3 hurricane, causing no flooding at Calvert Cliffs but "considerable flooding" at Turkey Point (which would be inundated during hurricanes stronger than Category 3);
  • Disruption of fuel supplies during severe storms;
  • Power-plant disruptions due to drought; and
  • Power lines, transformers and electricity distribution systems face increasing risks of physical damage from the hurricanes, storms and wildfires that are growing more frequent and intense. For example, in February 2013, over 660,000 customers lost power across eight states in the US Northeast affected by a winter storm bringing snow, heavy winds, and coastal flooding to the region and resulting in significant damage to the electric transmission system.


Many incidents illustrate the connections between climate, water and nuclear power in the US:

  • From February 8−11, 2013, Winter Storm Nemo brought snow and high winds to 19 nuclear energy facilities in the Northeast and mid-Atlantic − 18 facilities operated continuously at or near full power throughout the storm while Entergy's Pilgrim 1 reactors in Massachusetts safely shut down on February 9 due to a loss of off-site power (restored the following day).[6]
  • In October 2012, ports and power plants in the Northeast were either damaged or experienced shutdowns as a result of Hurricane Sandy. More than eight million customers lost power in 21 affected states.[1] Hurricane Sandy affected 34 nuclear energy facilities in the Southeast, mid-Atlantic, Midwest and Northeast. Twenty-four nuclear energy facilities continued to operate throughout the event. Seven were already shut down for refueling or inspection. Three reactors shut down: Salem 1, New Jersey, was manually shut down due to high water at its outside circulation water pumps; Indian Point 3, New York, automatically shut down due to external power grid disruption; Nine Mile Point 1, New York, automatically shut down due to external power grid disruption. Exelon declared an alert due to the high water level at the cooling water intake structure of its Oyster Creek, New Jersey nuclear plant; the alert ended after 47 hours when the water level dropped.[6]
  • In August 2012, Dominion Resources shut down one reactor at the Millstone Nuclear Power Station in Connecticut because the temperature of the intake cooling water, withdrawn from the Long Island Sound, was too high. Water temperatures were the warmest since operations began in 1970. No power outages were reported but the two-week shutdown resulted in the loss of 255,000 megawatt-hours of power, worth several million dollars.[1]
  • In August 2012, Entergy's Waterford 3 reactor, Louisiana, was temporarily shut down as a precaution due to projected high winds (Hurricane Isaac).[6]
  • In July 2012, four coal-fired power plants and four nuclear power plants in Illinois requested permission to exceed their permitted water temperature discharge levels. The Illinois Environmental Protection Agency granted special exceptions to the eight power plants, allowing them to discharge water that was hotter than allowed by federal Clean Water Act permits. [1]
  • In July 2012, the Vermont Yankee had to limit output four times because of low river flow and heat; and FirstEnergy Corp's Perry 1 reactor in Ohio dropped production because of above-average temperatures.[2]
  • In September 2011, high temperatures and high electricity demand-related loading tripped a transformer and transmission line near Yuma, Arizona, starting a chain of events that led to the shut down of the San Onofre nuclear plant with power lost to the entire San Diego County distribution system, totaling approximately 2.7 million power customers, with outages as long as 12 hours. [1]
  • On 27−28 August 2011, Hurricane Irene affected 24 nuclear power plants along the East Coast. Eighteen reactors remained at or near full power throughout the storm. Power output from four reactors was temporarily reduced as a precaution. One plant temporarily shut down as a precaution − Constellation Energy declared an unusual event when the Calvert Cliffs 1, Maryland, reactor automatically shut down due to debris striking an external electrical transformer.[6]
  • On 27 April 2011, three Browns Ferry reactors, Alabama, automatically shut down when strong storms knocked out off-site power. Emergency diesel generators were used for just over five days.[6]
  • On 16 April 2011, Dominion Resources' two Surry reactors, Virginia, automatically shut down after a tornado damaged a switchyard and knocked out off-site power.[6]
  • In the Summer of 2010, the Hope Creek nuclear power plant in New Jersey and Exelon's Limerick plant in Pennsylvania had to reduce power because the temperatures of the intake cooling water, withdrawn from the Delaware and the Schuylkill Rivers respectively, were too high and did not provide sufficient cooling for full power operations. [1]
  • On 6 June 2010, DTE Energy's Fermi 2 reactor, Michigan, automatically shut down after a tornado knocked out off-site power to the site. The tornado caused some external damage.[6]
  • On 1 September 2008, Entergy's River Bend reactor, Louisiana, was manually shut down ahead of the approach of Hurricane Gustav. The shut down proceeded safely as designed but the hurricane caused some external damage.[6]
  • In 2007, 2010, and 2011, the Tennessee Valley Authority's (TVA) Browns Ferry Nuclear Plant in Athens, Alabama, had to reduce power output because the temperature of the Tennessee River was too high to discharge heated cooling water from the reactor without risking ecological harm to the river. TVA was forced to curtail the power production of its reactors, in some cases for nearly two months. While no power outages were reported, the cost of replacement power was estimated at US$50 million. [1] From August 5−12, 2008, the TVA lost a third of nuclear capacity due to drought conditions; all three Browns Ferry reactors were idled to prevent overheating of the Tennessee River.[2]
  • On 20 August 2009, lightning struck transmission lines knocking out off-site power to the Wolf Creek reactor, Kansas, and the plant automatically shut down.[6]
  • In August 2006, two reactors at Exelon's Quad Cities Generating Station in Illinois had to reduce electricity production to less than 60% capacity because the temperature of the Mississippi River was too high to discharge heated cooling water. [1] The Dresden and Monticello plants in Illinois cut power to moderate water discharge temperatures from July 29 to August 2.[2]
  • In July 2006, one reactor at American Electric Power's D.C. Cook Nuclear Plant in Michigan was shut down because the high summer temperatures raised the air temperature inside the containment building above 48.9°C, and the temperature of the cooling water from Lake Michigan was too high to intake for cooling. The plant could only be returned to full power after five days.[1]
  • On 28 August 2005, Hurricane Katrina knocked out off-site power to Entergy's Waterford 3 reactor, Louisiana, and a manual shut down proceeded. Emergency diesel generators were used for 4.5 days.[6]
  • On 24 September 2004, Hurricane Jeanne prompted a manual shut down of NextEra Energy's St. Lucie 1, 2 reactors, Florida, then caused loss of off-site power. Emergency diesel generators functioned as designed.[6]
  • In 2003, Hurricane Charley led to a shut-down of the Brunswick 1 reactor in North Carolina due to loss of off-site power because of a trip of the station auxiliary transformer. The transformer trip was due to an electrical fault on a transmission system line. Operators manually shut down the reactor.[7]
  • On 24 June 1998, FirstEnergy's Davis Besse reactor, Ohio, received a direct hit by an F2 tornado. The plant automatically shut down and emergency diesel generators (EDG) provided back-up power.[6] One EDG had to be started locally because bad switch contacts in the control room prevented a remote start. Then, problems due to faulty ventilation equipment arose, threatening to overheat the EDGs. Even with the EDGs running, the loss of offsite power meant that electricity supply to certain equipment was interrupted, including the cooling systems for the onsite spent fuel pool. Water temperature in the pool rose from 43°C to 58°C. Offsite power was restored to safety systems after 23 hours just as one EDG was declared inoperable.[7]
  • On 24 August 1992, Category 5 Hurricane Andrew knocked out off-site power to NextEra Energy's Turkey Point 3, 4 reactors, Florida, and damaged electrical infrastructure. Manual plant shut down proceeded and emergency diesel generators were used for six days, 10 hours.[6] All offsite communications were lost for four hours during the storm and access to the site was blocked by debris and fallen trees. The nuclear power station's fire protection system was also destroyed.[7]
  • In 1988, drought, high temperatures and low river volumes forced Commonwealth Edison to reduce power by 30% percent or in some cases shut down reactors at the Dresden and Quad Cities plants in Illinois. "That was the first wake-up call that plants would be vulnerable in a climate-disrupted world," said David Kraft, director of the Nuclear Energy Information Service.[2]


Of course, the problems are not unique to the US. A few examples:

  • In July 2009, France had to purchase power from the UK because almost a third of its nuclear generating capacity was lost when it had to cut production to avoid exceeding thermal discharge limits.[2]
  • In 2003, France, Germany and Spain had to choose between allowing reactors to exceed design standards and thermal discharge limits and shutting down reactors. Spain shut down its reactors, while France and Germany allowed some to operate and shut down others.[2] The same problems occurred in the Summer of 2006.[3]
  • On 8 February 2004, both Biblis reactors (A and B) in Germany were in operation at full power. Heavy storms knocked out power lines. Because of an incorrectly set electrical switch and a faulty pressure gauge, the Biblis-B turbine did not drop, as designed, from 1,300 to 60 megawatts, maintaining station power after separating from the grid. Instead the reactor scrammed. When Biblis-B scrammed with its grid power supply already cut off, four emergency diesel generators started. Another emergency supply also started but, because of a switching failure, one of the lines failed to connect. These lines would have been relied upon as a backup to bring emergency diesel power from Biblis-B to Biblis-A if Biblis-A had also been without power. The result was a partial disabling of the emergency power supply from Biblis-B to Biblis-A for about two hours. Then, the affected switch was manually set by operating personnel.[7]


A study by researchers at the University of Washington and in Europe, published in Nature Climate Change, found that generating capacity at thermoelectric plants in the US could fall by 4.4−16% between 2031 and 2060 depending on cooling system type and climate change scenarios.[4]

Prof. Dennis Lettenmaier, one of the authors of study, told InsideClimate News the problems will be two-fold.[5] First, water temperatures will be higher because of raised air temperatures, and will be too high at times to adequately cool the plant. Secondly, there may simply not be enough water to safely divert the flow and return it to the waterway. Climate models project a greater probability of low river levels due to a more variable climate. Lower river or lake levels would mean there would be less water available to diffuse the warmth that is returned. Plants currently have discharge restrictions to prevent ecological damage from downstream thermal pollution. With lower water levels, the plants would be forced to shut down more often.

Lettenmaier said the study's findings might discourage operators from applying for relicensing of ageing facilities, because of the expensive upgrades that would be required. "That could be the last nail in the coffin," he said. (For example the the Oyster Creek (NJ) plant will close in 2019 in part because the utility prefers closure instead of installing a state-mandated cooling tower to minimise damage to Barnegat Bay.) Plants using cooling towers rather than once through cooling will also be affected by climate change, but not nearly as much.

The impacts of climate change could be even bigger in Europe, according to the Nature Climate Change study. Power production in European thermoelectric plants could drop by 6.3−19% between 2031 and 2060 due to increased shut-downs.

The Nature Climate Change article states: "In addition, probabilities of extreme (>90%) reductions in thermoelectric power production will on average increase by a factor of three. Considering the increase in future electricity demand, there is a strong need for improved climate adaptation strategies in the thermoelectric power sector to assure future energy security."

[1] Department of Energy, July 2013, 'U.S. Energy Sector Vulnerabilities to Climate Change and Extreme Weather'
[2] Robert Krier, 15 Aug 2012, 'Extreme Heat, Drought Show Vulnerability of Nuclear Power Plants', InsideClimate News,
[3] Susan Sachs, 10 Aug 2006, 'Nuclear power's green promise dulled by rising temps',
[4] Michelle T. H. van Vliet et al., June 2012, 'Vulnerability of US and European electricity supply to climate change', Nature Climate Change, Vol.2, pp.676–681,
[5] Robert Krier, 13 June 2012, 'In California, No Taboos Over Coastal Climate Threats', InsideClimate News,
[6] Nuclear Energy Institute, 'Through the Decades: History of US Nuclear Energy Facilities Responding to Extreme Natural Challenge',
[7] Hirsch, Helmut, Oda Becker, Mycle Schneider and Antony Froggatt, April 2005, 'Nuclear Reactor Hazards: Ongoing Dangers of Operating Nuclear Technology in the 21st Century', Report prepared for Greenpeace International,

Further reading:
Section D.2 of the Greenpeace report cited immediately above addresses the following topics:

  • Consequences of Climate Change for NPP Hazards
  • Examples of Flooding
  • Examples of Storm Events
  • Vulnerability of Atomic Power Plants in the Case of Grid Failure
  • Vulnerability of Atomic Power Plants in the Case of Flooding
  • Vulnerability of Nuclear Power Plants by Other Natural Hazards
  • Possible Counter-measures

Water supply - a limiting factor in energy production

Nuclear Monitor Issue: 

Higher water temperatures and reduced river flows in Europe and the United States in recent years have resulted in reduced production, or temporary shutdown, of several thermoelectric power plants, resulting in increased electricity prices and raising concerns about future energy security in a changing climate. Thermoelectric (nuclear or fossil-fuelled) power plants, supply 91% and 78% of total electricity in the US and Europe respectively, thus disruption to their operation is a significant concern for the energy sector.

A study published June 3, 2012 in Nature Climate Change projects further disruption to supply, with a likely decrease in thermoelectric power generating capacity of between 6-19% in Europe and 4-16% in the United States for the period 2031-2060, due to lack of cooling-water. The likelihood of extreme (>90%) reductions in thermoelectric power generation will, on average, increase by a factor of three.

Compared to other water use sectors (e.g. industry, agriculture, domestic use), the thermoelectric power sector is one of the largest water users in the US (at 40%) and in Europe (43% of total surface water withdrawals). While much of this water is 'recycled' the power plants rely on consistent volumes of water, at a particular temperature, to prevent overheating of power plants. Reduced water availability and higher water temperatures - caused by increasing ambient air temperatures associated with climate change - are therefore significant issues for electricity supply.

According to the authors, while recirculation (cooling) towers will be affected, power plants that rely on 'once-through cooling' are the most vulnerable. These plants pump water direct from rivers, lakes, or the sea, to cool the turbine condensers, water is then returned to its source, often at temperatures significantly higher than when the water entered the plant, causing yet another problem, that of downstream thermal pollution.

"Higher electricity prices and disruption to supply are significant concerns for the energy sector and consumers, but another growing concern is the environmental impact of increasing water temperatures on river ecosystems, affecting, for example, life cycles of aquatic organisms," says Michelle van Vliet, from Wageningen University and Research Center in the Netherlands.

Both the US and Europe have strict environmental standards with regard to the volume of water withdrawn and the temperature of the water discharged from power plants. Thus warm periods coupled with low river flows can lead to conflicts between environmental objectives and energy production. Additionally, given the substantial investments and the long-life expectancy (50-60 years) of thermoelectric power plants, such projections are important for the electricity sector such that it can adapt to changes in cooling water availability and plan infrastructure investments accordingly.

One adaptation strategy is to reduce reliance on freshwater sources and replace with saltwater, according to co-author Pavel Kabat, Director/CEO of the International Institute for Applied Systems Analysis (IIASA). "However given the life expectancy of power plants and the inability to relocate them to an alternative water source, this is not an immediate solution but should be factored into infrastructure planning. Another option is to switch to new gas-fired power plants that are both more efficient than nuclear- or fossil fuel- power plants and that also use less water."

The study focused on 61 power plants in central and eastern U.S. and 35 power plants in Europe, both nuclear and coal-fired power plants with different cooling systems were included. Considering the projected increase in demand for electricity in these regions and globally, the study reinforces the need for improved climate adaptation strategies in the thermoelectric power sector to ensure future energy security and environmental objectives are not compromised.

The projections are based on new research that combines hydrological and water temperature models over the twenty-first century with an electricity production model. The models consider two contrasting scenarios for the energy sector - one of low levels of technological change in the energy sector and one that assumes environmental sustainability and a rapid transition to renewable energy.

The peer reviewed full report is available at:

The research was undertaken by an international team of scientists from the Earth System Science and Climate Change Group, Wageningen University and Research Centre; The Netherlands, The Department of Civil and Environmental Engineering, University of Washington, Seattle, USA; Forschungszentrum Jülich, Institute of Energy and Clmate Research–System Analyses and Technology Evaluation, Jülich, Germany; and the International Institute for Applied Systems Analysis, Laxenburg, Austria.

Reference: Vulnerability of US and European electricity supply to climate change. Michelle T. H. van Vliet, John R. Yearsley, Fulco Ludwig, Stefan Vögele, Dennis P. Lettenmaier and Pavel Kabat. Nature Climate Change, 10.1038/NCLIMATE1546, June 3 2012
Contact: Leane Regan, International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.
Tel: +43 664 443 0368
Email:  regan[at]

Far from "solving global warming," n-power too risky in destabilized climate

Nuclear Monitor Issue: 
Kevin Kamps at Beyond Nuclear

The nuclear power industry has spent a lot of money on public relations and national advertizing campaigns aimed at convincing the public and decision makers that atomic energy is a solution to the worsening climate crisis. But extreme weather, likely made more frequent and intense by the growing concentration of heat-trapping greenhouse gases in the atmosphere, means that nuclear power is too risky to operate amidst the climate chaos.

In the U.S., current historic floods on the Missouri River, threatening the Fort Calhoun and Cooper (of the same design as Fukushima Daiichi Units 1 to 4) atomic reactors in Nebraska, have underscored the point. So has a historic wildfire that recently came dangerously close to tens of thousands of 55 gallon (208 liter) barrels of plutonium-contaminated wastes at the Los Alamos nuclear weapons lab in New Mexico.

Fortunately, a record number of tornadoes, some of record size, this spring across the Midwest, South, and Southeast U.S. did not directly strike atomic reactors, although some were forced to shut down as a safety precaution when primary electric grids failed. Previous direct hits by tornadoes at atomic reactors, such as Davis-Besse, Ohio, in June 1998, came close to causing a catastrophic radioactivity release. Similarly, Hurricane Andrew at Turkey Point nuclear power plant near Miami in 1992 required the diversion of diesel fuel supplies from area hospitals in order to keep emergency backup generators running for many days, to operate vital safety and cooling systems.

Given their vulnerable locations, on sea coasts, rivers, the Great Lakes, etc., U.S. atomic reactors grow more risky with the worsening climate crisis. In fact, the 104 operating reactors at 65 sites in 30 states across the U.S. are almost all vulnerable to extreme weather events.

24 operating reactors at 14 sites are located on our sea coasts, vulnerable to hurricanes and storm surges, and eventually, sea level rise. Not included in this count is River Bend nuclear power plant, on the Mississippi River in Louisiana but far from the ocean, which was forced to shut down during Hurricane Katrina in 2005 for safety’s sake. Thus, even "inland" reactors are at risk from powerful enough hurricanes. 64 operating reactors at 39 sites are located along rivers, potentially vulnerable to floods. Certain rivers, of course, are more likely to flood than others. A total of 88 reactors at 53 sites are vulnerable to inundation.

Such an inundation, although caused by an earthquake-spawned tsunami, led to the ongoing triple reactor meltdown and high-level radioactive waste pool releases at Fukushima Daiichi. Many U.S. reactors are also at risk of earthquakes, and some, as on the California coast at San Onofre and Diablo Canyon, to tsunamis.         

13 operating reactors at 9 sites are located on the U.S. side of the Great Lakes. An additional 20 reactors are located on the Canada side of the Great Lakes in Ontario. Among other things, these reactors are vulnerable to tornadoes. A tornado damaged the Fermi 2 nuclear power plant in Monroe, Michigan in June, 2010, knocking out the primary electric grid. Fortunately, this happened after it had been discovered, just 4 years earlier, that Fermi 2’s emergency back-up diesel generators had been inoperable for two decades, from 1986 to 2006. Fermi 2 is the largest General Electric Boiling Water Reactor of the Mark 1 design in the world – a replica of Fukushima Daiichi Units 1 to 4, only significantly bigger, and with more high-level radioactive waste in its storage pool than all four failed Japanese units put together. These Great Lakes reactors are located immediately adjacent to the drinking water supply for 40 million people downstream in the U.S., Canada, and numerous Native American/First Nations, comprising a remarkable 20% of the world’s surface fresh water.

In addition to catastrophic risks from extreme weather, the warming, or absence of enough, cooling water could force atomic reactors to power down, or shut down entirely. Dave Kraft of Nuclear Energy Information Service in Chicago has documented several such occurrences in the U.S. and Europe in a fact sheet entitled “ ‘It’s the water, stupid!’ Nuclear power won’t work in Global Warming World.”

In the summer of 1988, nearly 100 reactor-days of operations at Commonwealth Edison reactors in Illinois were lost due to severe drought, exceedingly high temperatures, low river volumes and flow rates.

In the summer of 2003, the Western European heat wave that killed 30,000 people also wreaked havoc with atomic reactor operations. Spain shut down its reactors. France and Germany shut some reactors down, but allowed others to continue operating, exceeding design standards and thermal discharge regulations. At Fessenheim in France, local firefighters were called upon to hose down overheating reactor containments. And at Blayais on the Gironda River estuary in France, thermal discharge limits were violated 50 times over.

In the summer of 2006, the twin reactors at Donald C. Cook nuclear power plant in Michigan, were forced to shut down during a severe heat wave. Internal containment building temperatures exceeded the regulatory limit of 120 degrees Fahrenheit (49 degrees Celsius) for over 8 hours, and the temperature could not be reduced. Remarkably, this occurred despite Cook drawing its cooling water from Lake Michigan, one of the single largest bodies of fresh water on the planet.

From August 5-12, 2008, the Tennessee Valley Authority (a federal nuclear utility) lost one-third of its nuclear capacity due to serious drought conditions in the Southeastern U.S. All three reactors at Browns Ferry in Alabama were shut down to prevent overheating the Tennessee River. The Southeast already hosts over two dozen atomic reactors. Construction on four new ones is already underway at Vogtle in Georgia and Summer in South Carolina.

Again in July, 2009, 20 gigawatts-electric of France’s total nuclear generating capacity of 63 GW-e was out of service due to reaching thermal discharge limits for French rivers.

Not only are energy efficiency and renewables such as solar power and wind power ever more cost effective than nuclear power, they are also safer and more reliable in a global warming world. They do not require huge amounts of cooling water, as do atomic reactors. Best of all, they are genuinely clean – representing actual solutions to the climate crisis.

Source and contact: Kevin Kamps at Beyond Nuclear, 6930 Carroll Avenue, Suite 400, Takoma Park, MD 20912, USA.
Tel: 301.270.2209
Fax: 301.270.4000

Beyond Nuclear

Nuclear energy and renewable power: which is the best climate change mitigation option?

Nuclear Monitor Issue: 
Benjamin Sovacool

This article assesses different lifecycle studies of greenhouse gas equivalent emissions for nuclear and renewable power plants to identify a subset of the most current, original, and transparent studies. It calculates that mean value for greenhouse gas emissions for nuclear energy over the lifetime of a plant are quite high at about 66 carbon dioxide equivalent per kWh (gCO2e/kWh). Offshore wind power has less than one-seventh the carbon equivalent emissions of nuclear plants; large-scale hydropower, onshore wind, and biogas, about one-sixth the emissions; small-scale hydroelectric and solar thermal one-fifth. This makes these renewable energy technologies seven-, six-, and five-times more effective on a per kWh basis at fighting climate change. Policymakers would be wise to embrace these more environmentally friendly technologies if they are serious about producing electricity and mitigating climate change.

Advocates of nuclear power have recently framed it as an important part of any solution aimed at fighting climate change and reducing greenhouse gas emissions. Opponents of nuclear power have responded in kind. Which side is right?

I. Introduction
To find out which side is right, this paper screened 103 lifecycle studies of greenhouse gas equivalent emissions for nuclear power plants to identify a subset of the most current, original, and transparent studies. It begins by briefly detailing the separate components of the nuclear fuel cycle before explaining the methodology of the survey and exploring the variance of lifecycle estimates. It calculates that while the range of emissions for nuclear energy over the lifetime of a plant reported from qualified studies examined is from 1.4 grams of carbon dioxide equivalent per kWh (gCO2e/kWh) to 288 gCO2e/kWh, the mean value is 66 gCO2e/kWh.

The article then explains some of the factors responsible for the disparity in lifecycle estimates, in particular identifying errors in both the lowest estimates (not comprehensive) and the highest estimates (failure to consider co-products). It should be noted that nuclear power is not directly emitting greenhouse gases, but rather that life-cycle emissions account for fossil fuel emissions occurring elsewhere and indirectly attributable to nuclear plant construction, operation, uranium mining and milling, and plant decommissioning.

II. Nuclear Lyfecycle
Engineers generally classify the nuclear fuel cycle into two types: “once-through” and “closed.” Conventional reactors operate on a “once-through” mode that discharges spent fuel directly into disposal. Reactors with reprocessing in a “closed” fuel cycle separate waste products from unused fissionable material so that it can be recycled as fuel. Reactors operating on closed cycles extend fuel supplies and have clear advantages in terms of storage of waste disposal, but have disadvantages in terms of cost, short-term reprocessing issues, proliferation risk, and fuel cycle safety.

Despite these differences, both once-through and closed nuclear fuel cycles involve at least five interconnected stages that constitute a nuclear lifecycle: the “frontend” of the cycle where uranium fuel is mined, milled, converted, enriched, and fabricated; the construction of the plant itself; the operation and maintenance of the facility; the “backend” of the cycle where spent fuel is conditioned, (re)processed, and stored; and a final stage where plants are decommissioned and abandoned mines returned to their original state.

III. Review of lifecycle studies
To assess the total carbon dioxide-equivalent emissions over the course of the nuclear fuel cycle, this study began by reviewing 103 lifecycle studies estimating greenhouse gas emissions for nuclear plants. These 103 studies were narrowed according to a three-phase selection process.

  • First, given that the availability of high quality uranium ore changes with time, and that mining, milling, enrichment, construction, and reactor technologies change over the decades, the study excluded surveys more than ten years old (i.e., published before 1997). Admittedly, excluding studies more than a decade old is no guarantee that the data utilized by newer studies is in fact new. One analysis, for instance, relies on references from the 1980s for the modeling of uranium mining; data from 1983 for modeling uranium tailing ponds; 1996 data for uranium conversion; and 2000 data for uranium enrichment. Still, excluding studies more than ten years old is an attempt to hedge against the use of outdated data, and to ensure that recent changes in technology and policy are included in lifecycle estimates. Still, 40 studies analyzed are excluded by their date.
  • Second, this study excluded analyses that were not in the public domain, cost money to access, or were not published in English. Nine studies excluded for lack of accessibility.
  • Third, 35 studies were excluded based on their methodology. These studies were most frequently discounted because they either relied on “unpublished data” or utilized “secondary sources.” Those relying on “unpublished data” contained proprietary information, referenced data not published along with the study, did not explain their methodology, were not transparent about their data sources, or did not detail greenhouse gas emission estimates for separate parts of the nuclear fuel cycle in gCO2e/kWh. Those utilizing “secondary sources” merely quoted other previously published reports and did not provide any new calculations or synthetic analysis on their own.

Excluding detailed studies that rely on unpublished or non-transparent data does run the risk of including less detailed (and less rigorous) studies relying on published and open data. Simply placing a study in the public domain does not necessarily make it “good.” However, the author believes that this risk is more than offset by the positives benefits of transparency and accountability. Transparency enhances validity and accuracy; public knowledge is less prone to errors, and more subject the process of debate and dialogue that improves the quality of information, tested against other propositions in the marketplace of ideas. Furthermore, transparency is essential to promoting social accountability. Society simply cannot make informed decisions about nuclear power without public information; since the legitimacy of nuclear power is a public issue, the author believes that only results in the public domain should be included.

The survey conducted here found 19 studies that met all criteria: they were published in the past 10 years, accessible to the public, transparent about their methodology, and provided clear estimates of equivalent greenhouse gas emissions according to the separate parts of the nuclear fuel cycle. These studies were “weighed” equally; that is, they were not adjusted in particular for their methodology, time of release within the past ten years, or how rigorously they were peer reviewed or cited in the literature.

A somewhat rudimentary statistical analysis of these 19 studies reveals a range of greenhouse gas emissions over the course of the nuclear fuel cycle at the extremely low end of 1.4 gCO2e/kWh and the extremely high end of 288 gCO2e/kWh. Accounting for the mean values of emissions associated with each part of the nuclear fuel cycle, the mean value reported for the average nuclear power plant is 66 gCO2e/kWh. The frontend component of the nuclear cycle is responsible for 38 percent of equivalent emissions; decommissioning 18 percent; operation 17 percent; backend 15 percent; and construction 12 percent.

IV. Assessing the disparity in estimates
What accounts for such a wide disparity among lifecycle estimates of greenhouse gas emissions associated with the nuclear fuel cycle? Studies primarily differ in terms of their scope; assumptions regarding the quality of uranium ore; assumptions regarding type of mining; assumptions concerning method of enrichment; whether they assessed emissions for a single reactor or for a fleet of reactors; whether they measured historical or marginal/future emissions; assumptions regarding reactor type, site selection, and operational lifetime; and type of lifecycle analysis.

4.1 Scope
Some studies included just one or two parts of the nuclear fuel cycle, whereas others provided explicit details for even subcomponents of the fuel cycle. One study, for example, analyzed just the emissions associated with construction and decommissioning for reactors across the world, where another assessed the carbon equivalent for the construction of the Sizewell B nuclear reactor in the United Kingdom. Their estimates are near the low end of the spectrum, at between 3 and 11.5 gCO2e/kWh. In contrast, another study looked at every single subcomponent of the fuel cycle, and produced estimates near the high end of the spectrum at 112 to 166 gCO2/kWh.

4.2 Quality of Uranium Ore
Studies varied in their assumptions regarding the quality of uranium ore used in the nuclear fuel cycle. Low-grade uranium ores contain less than 0.01% yellowcake, and is at least ten times less concentrated than high-grade ores, meaning it takes ten tons of ore to produce 1 kg of yellowcake. Put another way, if uranium ore grade declines by a factor of ten, then energy inputs to mining and milling must increase by at least a factor of ten . This can greatly skew estimates, as uranium of 10% U3O8 has emissions for mining and milling at just 0.04 gCO2/kWh, whereas uranium at 0.013% grade has associated emissions more than 1,500 times greater at 67 gCO2/kWh. The same trend is true for the emissions associated with uranium mine land reclamation. With uranium of 10 percent grade, emissions for reclamation are just 0.07 gCO2e/kWh, but at 0.013%, they are 122 gCO2/kWh.

4.3 Open Pit or Underground Mining
The type of uranium mining will also reflect different CO2e emissions. Open pit mining often produces more gaseous radon and methane emissions than underground mines, and mining techniques will release varying amounts of CO2 based on the explosives and solvents they use to purify concentrate. They also point out that the carbon content associated with acid leeching used to extract uranium can vary, as well as the emissions associated with the use of lime to neutralize the resulting leached tailings. The emissions associated with uranium mining depend greatly on the local energy source for the mines. In Canada, uranium extracted from mines closer to industrial centers rely on more efficient, centrally generated power. In contrast, remote mines there have relied on less efficient diesel generators that consumed 45,000 tons of fossil fuel per year/mine, releasing up to 138,000 tons of carbon dioxide every year.

4.4 Gaseous Diffusion or Centrifuge Enrichment
Another significant variation concerns the type of uranium enrichment. Gaseous diffusion is much more energy-intense, and therefore has higher associated carbon dioxide emissions. Gaseous diffusion requires 2,400 to 2,600 kWh per seperative work unit (a function measuring the amount of uranium processed proportioned to energy expended for enrichment), compared to just 40 kWh per SWU for centrifuge techniques. The energy requirements for these two processes are so vastly different because gaseous diffusion is a much older technology, necessitating extensive electrical and cooling systems that are not found in centrifuge facilities.

Emissions will further vary on the local power sources at the enrichment facilities. One study calculated 9 gCO2e/kWh for Chinese centrifuge enrichment relaying on a mix of renewable and centralized power sources, but up to 80 gCO2e/kWh if gaseous diffusion is powered completely by fossil fuels.

4.5 Individual or Aggregate Estimates
Some studies look at just specific reactors, while others assess emissions based on industry, national, and global averages. These obviously produce divergent estimates. One study, for instance, looked at just two actual reactors in Switzerland, the Gosgen Pressurized Water Reactor and Liebstadt Boiling Water Reactor and calculate emissions at 5 to 12 gCO2e/kWh, whereas other studies look at global reactor performance and reach estimates more than 10 times greater.

4.6 Historical or Marginal/Future Emissions
Yet another difference concerns whether researchers assessed historic, future, or prototypical emissions. Studies assessing historic emissions looked only at emissions related to real plants operating in the past; studies looking at future average emissions looked at how existing plants would perform in the years to come; studies analyzing prototypical emissions looked at how advanced plants yet to be built would perform in the future. One study, for example, found historical emissions for light water reactors in Japan from 1960 to 2000 to be rather high at between 10 and 200 gCO2e/kWh. Others looked at future emissions for the next 100 years using more advanced Pressurized Water Reactors and Boiling Water Reactors. Still other studies made different assumptions about future reactors, namely fast-breeder reactors using plutonium and thorium, and other Generation IV nuclear technology expected to be much more efficient if they ever reach commercial production.

4.7 Reactor Type
Studies varied extensively in the types of reactors they analyzed. More than 30 commercial reactor designs exist today, and each differs in its fuel cycle, output, and cooling system. The most common are the world’s 263 Pressurized Water Reactors, used in France, Japan, Russia and the U.S., which rely on enriched uranium oxide as a fuel with water as coolant. Boiling Water Reactors are second most common, with 92 in operation throughout the U.S, Japan, and Sweden, which also rely on enriched uranium oxide with water as a coolant. Then come Pressurized Heavy Water Reactors, of which there are 38 in Canada, that use natural uranium oxide with heavy water as a coolant. Next comes 26 gas-cooled reactors, used predominately in the United Kingdom, which rely on natural uranium and carbon dioxide as a coolant. Russia also operates 17 Light Water Graphite Reactors that use enriched uranium oxide with water as a coolant but graphite as a moderator. A handful of experimental reactors, including fast breeder reactors (cooled by liquid sodium) and pebble bed modular reactors (which can operate at fuel load while being refueled), still in the prototype stages, make up the rest of the world total.

To give an idea about how much reactor design can influence lifecycle emissions, CANDU reactors are the most neutron efficient commercial reactors, achieving their efficiency through the use of heavy water for both coolant and moderator, and reliance on low-neutron absorbing materials in the reactor core. CANDU reactors thus have the ability to utilize low-grade nuclear fuels and refuel while still producing power, minimizing equivalent carbon dioxide emissions. This could be why CANDU reactors have relatively low emissions (~15 gCO2e/kWh) compared to the average emissions from qualified studies as described by this work (~66 gCO2e/kWh).

4.8 Site Selection
Estimates vary significantly based on the specific reactor site analyzed. Location influences reactor performance (and consequential carbon equivalent emissions). Some of the ways that location may influence lifetime emissions include differences in:

  • Construction techniques, including available materials, component manufacturing, and skilled labor;
  • Local energy mix at that point of construction;
  • Travel distance for materials and fuel cycle components;
  • Associated carbon footprint with the transmission and distribution (T&D) network needed to connect to the facility;
  • Cooling fuel cycle based on availability of water and local hydrology;
  • Environmental controls based on local permitting and siting requirements.

Each of these can substantially affect the energy intensity and efficiency of the nuclear fuel cycle.

Consider two extremes. In Canada, the greenhouse gas-equivalent emissions associated with the CANDU lifecycle are estimated at about 15 gCO2e/kWh. CANDU reactors tend to be built with skilled labor and advanced construction techniques, and they utilize uranium that is produced domestically and relatively close to reactor sites, enriched with cleaner technologies in a regulatory environment with rigorous environmental controls. By contrast, the greenhouse-gas equivalent emissions associated with the Chinese nuclear lifecycle can be as high as 80 gCO2e/kWh. This could be because Chinese reactors tend to be built using more labor-intensive construction techniques, must import uranium thousands of miles from Australia, and enrich fuel primarily with coal-fired power plants that have comparatively less stringent environmental and air-quality controls.

4.9 Operational Lifetime
How long the plants at those sites are operated and their capacity factor influences the estimates of their carbon-dioxide equivalent intensity. A 30-year operating lifetime of a nuclear plant with a load factor of 82 percent tends to produce 23.2 gCO2/kWh for construction. Switch the load factor to 85 percent and the lifetime to 40 years, and the emissions drop about 25 percent to 16.8 gCO2/kWh. The same is true for decommissioning. A plant operating for 30 years at 82 percent capacity factor produces 34.8 gCO2/kWh for decommissioning, but drop 28 percent to 25.2 gCO2/kWh if the capacity factor improves to 85 percent and the plant is operated for 40 years.

Most of the qualified studies referenced above assume lifetime nuclear capacity factors that do not seem to match actual performance. Almost all of the qualified studies reported capacity factors of 85 to 98 percent, where actual operating performance has been less. While the nuclear industry in the U.S. has boasted recent capacity factors in the 90-percent range, average load factors over the entire life of the plants is very different: 66.3 percent for plants in the UK and 81 percent for the world average.

4.10 Type of Lifecycle Analysis
The type of lifecycle analysis can also skew estimates. Projections can be “top-down,” meaning they start with overall estimates of a pollutant, assign percentages to a certain activity (such as “cement manufacturing” or “coal transportation”), and derive estimates of pollution from particular plants and industries. Or they can be “bottom-up,” meaning that they start with a particular component of the nuclear fuel cycle, calculate emissions for it, and move along the cycle, aggregating them. Similarly, lifecycle studies can be “process-based” or rely on economic “input-output analysis.” “Process-based” studies focus on the amount of pollutant released—in this case, carbon dioxide or its equivalent—per product unit. For example, if the amount of hypothesized carbon dioxide associated with every kWh of electricity generation for a region was 10 grams, and the cement needed for a nuclear reactor took 10 kWh to manufacture, a process analysis would conclude that the cement was responsible for 100 grams of CO2. “Input-output” analysis looks at industry relations within the economy to depict how the output of one industry goes to another, where it serves as an input, and attempts to model carbon dioxide emissions as a matrix of interactions representing economic activity.

V. Conclusion
The first conclusion is that the mean value of emissions over the course of the lifetime of a nuclear reactor (reported from qualified studies) is 66 gCO2e/kWh, due to reliance on existing fossil-fuel infrastructure for plant construction, decommissioning, and fuel processing along with the energy-intensity of uranium mining and enrichment. Thus, nuclear energy is in no way “carbon free” or “emissions free,” even though it is much better (from purely a carbon equivalent emissions standpoint) than coal, oil, and natural gas electricity generators, but worse than renewable and small scale distributed generators (See Table 1).

Table 1: Lifecycle greenhouse gas emission estimates for various electricity generators



Estimate (gCO2e/kWh)


2.5 MW, Offshore



3.1 MW, Reservoir



1.5 MW, Onshore



Anaerobic Digestion



300 kW, Run-of-River


Solar Thermal

80 MW, Parabolic Trough



Forest Wood Co-combustion with hard coal



Forest Wood Steam Turbine



Short Rotation Forestry Co-combustion with hard coal



Forest Wood Reciprocating Engine



Waste Wood Steam Turbine


Solar Photovoltaic

Polycrystalline silicone



Short Rotation Forestry Steam Turbine



80 MW, Hot Dry Rock



Short Rotation Forestry Reciprocating Engine



Various reactor types


Natural Gas

Various combined cycle turbines


Fuel Cell

Hydrogen from gas reforming



Various generator and turbine types


Heavy Oil

Various generator and turbine types



Various generator types with scrubbing



Various generator types without scrubbing



Source: This article is based on B.K. Sovacool, “Valuing the Greenhouse Gas Emissions from Nuclear Power: A Critical Survey,” Benjamin K. Sovacool. Energy Policy 36 (8) (August, 2008), pp. 2940-2953.

Contact: B.K. Sovacool is with the Lee Kuan Yew School of Public Policy at the National University of Singapore, 469C Bukit Timah Rd., Singapore, 259772.
Tel: +65 6516 501;