The Azimuth Project
Nuclear power



This page is about nuclear power as an Energy source. There’s a lot of controversy over nuclear power, as you can see below. Our goal here is to examine both sides of this argument carefully and dispassionately. Ultimately our goal should be to shed light on questions such as these:

What are the comparative merits of traditional light-water reactors and various newer kinds of reactors? How efficient are they? How safe? How much will they contribute to the danger of nuclear weapons proliferation? How much power can they generate, how soon? How can scientists improve their efficiency and safety?

However, for now we merely summarize the nuclear power used and proposed worldwide and then list some considered opinions from various people.


As of 2010, nuclear plants had a total capacity of 370 gigawatts. Here are the reactors types either in use today, or planned based on Wikipedia:

TypeNumberCoolantModeratorMax tempGen
Pressurized Water (PWR)260light water=330II
Boiling Water (BWR)93light water=288II
RBMK13light watergraphite270I
Pressurized Heavy Water (PHWR)43heavy water=267II
Gas cooled (GCR)32CO2,Hegraphite741II
Liquid Metal Cooled (LMFBR)2Na,Pb,BiNone545II
Advaned Boiling Water (ABWR)----III
Advanced Pressurized (APR)----III
Very high temperature (VHTR)-graphite1000IV
Molten salt MSR-UF4graphite1000IV
Gas cooled fast GFR?-HeNone850IV
Sodium cooled fast SFR-HeNone850IV
Lead-cooled fast reactor (LFR)-Pb,BiNone800IV

Various views

James Lovelock

James Lovelock writes:

I find it sad and ironic that the UK, which leads the world in the quality of its Earth and climate scientists, rejects their warnings and advice, and prefers to listen to the Greens. But I am a Green and I entreat my friends in the movement to drop their wrongheaded objection to nuclear energy.

Even if they were right about its dangers, and they are not, its worldwide use as our main source of energy would pose an insignificant threat compared with the dangers of intolerable and lethal heat waves and sea levels rising to drown every coastal city of the world. We have no time to experiment with visionary energy sources; civilisation is in imminent danger and has to use nuclear — the one safe, available, energy source — now or suffer the pain soon to be inflicted by our outraged planet.

James Hansen

There was an article in the newspaper The Australian about James Hansen and his thoughts on nuclear power. It

“We should undertake urgent focused research and development programs in next generation nuclear power,” said atmospheric physicist James Hansen, head of NASA’s Goddard Institute for Space Studies and adjunct professor at Columbia University’s Earth Institute in New York.

While renewable energies such as solar and wind were gaining in economic competition with coal-fired plants, Professor Hansen said they wouldn’t be able to provide baseload power for years to come.

Even in Germany, which pushed renewables heavily, they generated only 7 per cent of the nation’s power.

“It’s just too expensive,” said Professor Hansen, an expert in climate modelling, planetary atmospheres and the Earth’s climate.

“Right now, fossil fuels are the cheapest form of energy, except for operating nuclear plants,” he said on the first day of a lecture tour in Australia.

According to Professor Hansen, because the threat of global warming was so serious, nations such as the US, China and even Australia must crank up support for so-called third and fourth generation nuclear systems.

“Current nuclear plants are the second generation. The third generation is ready to build now,” he explained, pointing to conventional light water reactors, which generated heat by the fission of uranium fuel. Two fourth-generation technologies are on the drawing board. Fast reactors use liquid sodium metal as a coolant for the fission of metallic solid fuel, including existing nuclear waste and weapons-grade uranium and plutonium.

Thorium reactors use fluoride salt as the medium for the energy-producing nuclear reaction, so they don’t require production of fuel rods.

Professor Hansen admitted he was a late convert to advanced nuclear power. “But fourth generation solves two of the problems that made me sceptical,” he said.“

“One is nuclear waste. It uses over 99 per cent of the fuels, while second and third generations use less than 1 per cent, leaving a waste pile with a half-life of 100,000 years. Fourth generation burns almost all the fuel and waste has a half life of decades.”

No commercial scale fourth-generation plants exist, but seven nations, including Japan, France and China, have expertise or research and development projects. Which will get their first? “That’s an open question,” according to Professor Hansen.“

Stewart Brand

Stewart Brand also thinks we need nuclear power. He writes:

Can climate change be slowed and catastrophe avoided? They can to the degree that humanity influences climate dynamics. The primary cause of global climate change is our burning of fossil fuels for energy.

So everything must be done to increase energy efficiency and decarbonize energy production. Kyoto accords, radical conservation in energy transmission and use, wind energy, solar energy, passive solar, hydroelectric energy, biomass, the whole gamut. But add them all up and it’s still only a fraction of enough. Massive carbon “sequestration” (extraction) from the atmosphere, perhaps via biotech, is a widely held hope, but it’s just a hope. The only technology ready to fill the gap and stop the carbon dioxide loading of the atmosphere is nuclear power.

Nuclear certainly has problems—accidents, waste storage, high construction costs, and the possible use of its fuel in weapons. It also has advantages besides the overwhelming one of being atmospherically clean. The industry is mature, with a half-century of experience and ever improved engineering behind it. Problematic early reactors like the ones at Three Mile Island and Chernobyl can be supplanted by new, smaller-scale, meltdown-proof reactors like the ones that use the pebble-bed design. Nuclear power plants are very high yield, with low-cost fuel. Finally, they offer the best avenue to a “hydrogen economy,” combining high energy and high heat in one place for optimal hydrogen generation.

The storage of radioactive waste is a surmountable problem. Many reactors now have fields of dry-storage casks nearby. Those casks are transportable. It would be prudent to move them into well-guarded centralized locations. Many nations address the waste storage problem by reprocessing their spent fuel, but that has the side effect of producing material that can be used in weapons. One solution would be a global supplier of reactor fuel, which takes back spent fuel from customers around the world for reprocessing. That’s the kind of idea that can go from “Impractical!” to “Necessary!” in a season, depending on world events.

The environmental movement has a quasi-religious aversion to nuclear energy. The few prominent environmentalists who have spoken out in its favor—Gaia theorist James Lovelock, Greenpeace cofounder Patrick Moore, Friend of the Earth Hugh Montefiore—have been privately anathematized by other environmentalists. Public excoriation, however, would invite public debate, which so far has not been welcome.

Amory Lovins

For a critical take on Stewart Brand’s views, see:

Stewart Brand is similarly critical of Amory Lovins in Brand’s book Whole Earth Discipline. For a more detailed discussion see:

Abstract. This paper challenges the view that nuclear power is competitive, necessary, reliable, secure, and affordable. The authors explain why nuclear power is uncompetitive, unneeded, and obsolete. The authors explore the economics of nuclear power by looking at past and future costs of new nuclear plants, what alternatives they must beat, and the rapidly shifting competitive landscape in which they must contend. They compare nuclear’s market success with that of energy competitors and contrast those in deployment speed, reliability, and overall adequacy. They also consider how government subsidies approaching or even exceeding 100% of nuclear power’s entire cost do not attract investors and that capitalists are instead flocking to competitors that offer lower costs and lower financial risks. By comparing all these options’ ability to protect the climate and enhance energy security, the authors show why nuclear power could never effectively deliver these crucial benefits even if it could find free-market buyers—while its carbon-free rivals do offer those benefits with greater scale, speed, and confidence.

A less technical summary is available here:

Abstract. This semi-technical article, summarizing a detailed and documented technical paper (see The Nuclear Illusion (2008)), compares the cost, climate protection potential, reliability, financial risk, market success, deployment speed, and energy contribution of new nuclear power with those of its low- or no-carbon competitors. It explains why soaring taxpayer subsidies haven’t attracted investors and how capitalists instead favor climate-protecting competitors with lower cost, construction time, and financial risk. Comparing all options’ ability to protect the earth’s climate and enhance energy security reveals why nuclear power could never deliver these promised benefits even if it could find free-market buyers—while its carbon-free rivals do offer highly effective climate and security solutions, far sooner, with higher confidence.

World Nuclear Association

The World Nuclear Association is an industry group; it studies a number of scenarios in this report:

For details, click the link and you’ll get to the Azimuth page about this report. If we had to summarize the report in just one chart, we’d probably use this:

They claim that with a low estimate of the growth of nuclear power production—“Nuclear Low” on the above graph—there will be a serious gap between power demand and clean power production, but that with a “Maximum Nuclear Committment” this gap will be closed… but only by 2080, which may be too late for serious global warming.

This report has been critically examined by Barry Brook, as discussed in the Azimuth page Nuclear century outlook.

Barry Brook

Barry Brook has begun a series of posts on his blog BraveNewClimate:

He’s studying four scenarios, two previously considered by the World Nuclear Association in their report called the “Nuclear Century Outlook” (or “NCO”). But he questions some of their assumptions, and considers the fourth scenario below to be most plausible;

  1. NCOL: NCO Low Scenario (going 602 gigawatts of power in 2030 and 1140 GW in 2060)

  2. NCOH: NCO High scenario (1350 GW in 2030, 3688 GW in 2060)

  3. TR1: A mid-growth scenario that tracks between NCO Low and High, but which peaks at around 2050 and slowly declines thereafter

  4. TR2: A high-growth scenario that is identical to NCO High through to 2030, after which the relative growth rate slows only gradually (absolute number of GW per year continues to increase).

Chris Uhlik

The following appeared as a guest post on Barry Brook’s blog:

His assumptions:

  • I’ll neglect all renewable sources such as hydro. They amount to only about 20% of electricity and don’t do anything about the larger fuel energy demand, so they won’t affect the answer very much.

  • Some energy sources are fuel-price intensive (e.g. natural gas) and some have zero fuel prices, but are capital intensive (e.g. wind). I’ll assume that nuclear is almost all capital intensive with only 35% of the cost coming from O&M and all the rest going to purchase costs plus debt service.

  • I’ll use 8% for cost of capital. Many utilities operate with a higher guaranteed return than this (e.g. 10.4%) but the economy historically provides more like 2–5% overall, so 8% seems quite generous.

  • I’ll assume 50 year life for nuclear power plants. They seem to be lasting longer than this, but building for more than 50 years seems wasteful as technologies advance and you probably want to replace them with better stuff sooner than that.

  • Back in the 1970′s we built nuclear power plants for about $0.80–0.90/watt (2009 dollars). In the 1980′s and 90′s we saw that price inflate to $2.09–3.39/watt (Palo Verde and Catawba) with a worst-case disaster of $15/watt (Shoreham). Current project costs are estimated at about $2.95/watt (Areva EPR). Current projects in China are ~$1.70/watt. If regulatory risks were controlled and incentives were aligned, we could probably build plants today for lower than the 1970′s prices, but I’ll pessimistically assume the current estimates of $3/watt.

  • Electricity vs Combustion: In an all nuclear, electricity-intensive, fossil-carbon-free future, many things would be done differently. For example, you won’t heat your house by burning natural gas. Instead you’ll use electricity-powered heat pumps. This will transfer energy away from primary source fuels like natural gas to electricity. Plug-in-hybrid cars will do the same for petroleum. In some cases, the total energy will go down (cars and heat pumps). In some cases, the total energy will go up (synthesizing fuel to run jet transport aircraft). I’ll assume the total energy demand in this future scenario is our current electricity demand plus an unchanged amount of energy in the fuel sector, but provided instead by electricity. I.e. 1.3 kW (today’s electricity) + 6.4 kW (today’s fuels, but provided by electricity with a mix of efficiencies that remains equivalent). This is almost certainly pessimistic, as electricity is often a much more efficient way to deliver energy to a process than combustion.

  • Zero GDP growth rate

His conclusion:

  • In this future, we need 7.7 kW per person, provided by $3/watt capitalized sources with 8% cost of capital and 35% surcharge for O&M. The cost of this infrastructure: $2,550/person/year or 5% of GDP.

More details, and alternative scenarios, are presented on his blog entry.

Nadja Kutz

Nadja Kutz, coauthor of the blog randform provides a short overview. This overview puts together scientific arguments in order to justify the claim that commercial nuclear power generation should be seen more critically.

The main points are:

Typical claims like “nuclear has been safe for a long time” are more or less void, since a lot of new and different nuclear technology than current technology will have to be installed due to the decline in uranium production. This makes the scientific evaluation and comparison with other methods of power generation difficult, especially when it comes to safety.

The kind of nuclear technology to be installed, namely breeder reactors, carries the danger of creating a “plutonium market”.

The waste problem may get completely out of control.

Antinuclear views

Some of those opposed to nuclear power claim that:

  1. Nuclear power is unsafe. To justify this claim, we would need to determine that nuclear is more dangerous per unit of energy than the forms of energy it would replace.

  2. Nuclear power, especially breeder reactors, dangerously increases the danger of nuclear weapons proliferation.

  3. Nuclear power is burdened by so many regulations that it takes a long time to get permits to build nuclear power plants, at least in the US — too long for them to save us from serious global warming.

  4. Nuclear power advocates are asking for big government subsidies. Solar power is now cheaper than nuclear.

Nuclear power in various countries


In France, nuclear power accounts for most of the electric power. This contributes to the fact that the per capita carbon dioxide emissions are lower in France than any other EU country: 6 tones of CO2 per capita in 2007, according to the Wikipedia article.

Electricity generation in France, by fuel - graph from the IEA


In Zwentendorf, Austria, there is a fully operational power plant that has never been used, due to a public vote against the use of nuclear power in 1978. See:


Today the owners of the power plant offer sightseeing tours, try to rent it as a film location, and have allowed the installation of solar panels for testing purposes on the main reactor building.

United States

David Kroodsma combined a map of potential earthquake risk, loosely measured by Peak Ground Acceleration (PGA), and nuclear power plant location. He states:

The PGA risk is what is typically used to set building codes. Most nuclear power plants are designed to operate under 0.2g PGA, and automatically shut off if the PGA exceeds 0.2g. However, they can withstand a PGA many times larger than that.

The magnitude scale is a measure of the total energy an earthquake releases. This is related to, but not directly proportional to the PGA. For instance, the recent earthquake in Christchurch, New Zealand, recorded a deadly PGA of 2.2g, even though it was “only” a 6.3 magnitude earthquake, while a recent earthquake in Chile, which measured 8.8 magnitude, recorded an acceleration of 0.78g.


For important issues related to nuclear power, see these Azimuth Library pages:

For different types of nuclear reactors, see these pages:

We need articles on more types of reactors, and detailed comparisons!

For the health effects of various different levels of radiation, see:

category: energy