Nuclear power: no solution to climate change

[kristopher]

Nuclear power: no solution to climate change

17 April 2010

Mark Diesendorf deputy director of the Institute for Environmental Studies at the University of New South Wales

* * *

The integral fast reactor doesn’t exist — it is the archetypal ink-moderated paper reactor. It’s true that a tiny physical version of this concept, called Experimental Breeder Reactor-2, once operated in the US. But experimental energy technologies are just that — experiments, designed to test a concept.

They have to be redesigned before they can be scaled-up to a medium-sized demonstration stage. Then, provided several successful demonstrations can be achieved over a period of many years, they usually need further design modifications before they could possibly move to commercial scale with full mass-production.

Realistically, this whole process would take at least 20 years in the US — much longer in Australia if our government was so foolish as to become involved.

Even if the integral fast reactor could somehow be brought to commercial reality in 2030, its proponents are naive to claim that it cannot be used to produce plutonium for nuclear weapons. A government that controls such a reactor could still build a conventional reprocessing plant to separate the plutonium from the other high-level nuclear waste. Safeguards are grossly inadequate.

The promoters of nuclear power claim that we have to choose between coal and nuclear, that there is no alternative. This is a false choice, between BHP-Billiton and … BHP-Billiton.

The real choice is between dirty and dangerous technologies (such as coal and nuclear) on one hand, and clean and safe technologies (that is, energy efficiency and renewable energy) on the other hand.

The nuclear lobby is fond of telling us that the sun doesn’t shine at night and the wind doesn’t blow all the time. On this simplistic basis, it claims that renewable energy cannot provide baseload, or 24-hour-a-day, power.

However, an ecologically sustainable electricity generating system will not be composed of wind alone or solar energy without storage alone.

Instead it will consist of several different types of power station with different properties: initially wind; bio-electricity, which is baseload; solar photovoltaic without storage; concentrated solar thermal power with thermal storage (potentially baseload); and gas turbines fuelled on sustainably produced ethanol or methanol.

All of these sources are commercially available or, in the case of concentrated solar thermal power, pre-commercial and on the brink of becoming commercial.

Taken together, they can form a system that it just as reliable as the dirty and dangerous systems based on fossil fuels and nuclear. Even wind power can be made as reliable as coal by geographic dispersion of wind farms and by adding a little intermittent back-up by means of gas turbines.

It is simply untrue that coal-fired power stations have to be kept running continuously to back-up wind.

Energy efficiency and solar hot water can also substitute for baseload coal. In Australia, 4600 megawatts of coal power are kept running between midnight and dawn for the sole purpose of heating water. As the switch is made to solar and gas hot water, these coal stations could be retired and their daytime generation replaced with gas power and renewable electricity.

Given effective government policies, which are lacking at present, renewable energy could supply at least 40% of Australia’s electricity by 2020.

Moving into the 2020s, we could also expect significant contributions from wave power, currently at the demonstration stage, and possibly hot rock geothermal power, which is close to medium-scale demonstration.

If we also include natural gas, we could phase out all of Australia’s coal power by 2030.

That’s the key measure recommended by Dr Hansen. By 2030 renewable electricity could generate at least 80% and possibly even 100% of our electricity.

The breakdown for 80% renewable electricity is: wind 25%; solar and biomass 20% each; gas and geothermal 10% each. If geothermal isn’t commercial, solar thermal could take up the slack.

But the 2006 Uranium Mining, Processing and Nuclear Energy Review, chaired by Dr Switkowski, knew better. It claimed that “nuclear power is the least-cost low-emission technology that can provide baseload power”.

However, there was no basis in the report for such a gratuitous statement, which was outside the terms of reference of the report. Not one of the authors had research experience in renewable energy. They all came from the nuclear industry or nuclear research. They were ignoring, among other things, the rapid growth of base-load solar power that has been occurring in Spain since 2004.

Another false claim made by nuclear proponents is that renewable energy cannot supply the energy needs of an industrial society. Actually, a square 30km by 30km filled with solar collectors and installed on marginal land could supply all of Australia’s current electricity demand. Beyond 2030, Australia could export vast quantities of renewable energy — stored as hydrogen, ammonia or methanol — to the rest of the world.

On a global scale, leading renewable energy researcher Bent Sorensen has shown that, with small improvements to existing technologies, there is more than enough renewable energy available to supply everyone on this planet with sufficient energy for a good standard of living by 2050. Of course, some regions have less potential than average, and other regions have more, just as with fossil fuels and uranium.

So, Sorensen allowed international trade in renewable energy by means of transmission line, pipeline and ship. More recently, Mark Jacobson and Mark Delucchi have outlined a case for 100% renewable energy on a global scale by 2030.

Nuclear power stations, whether conventional plant or hypothetical integral fast reactors, are inherently slow to build, because they are gigantic construction projects. On the other hand, most renewable energy systems are fast to build, because their components can be manufactured in factories. On-site installation is a minor part of the process.

In both 2008 and 2009, the biggest additions to the European Union’s generating capacity came from renewable electricity, mainly wind. In China, wind power’s generating capacity has doubled every year for the past fives years.

Such an extraordinary rate of growth is possible with renewable energy, but is impossible for coal and nuclear power. Nuclear power is a particularly slow technology to grow. It is neither a short-term nor medium-term solution to the climate crisis.

The fact that most renewable electricity systems are manufactured, while nuclear power stations are constructed, also explains why renewable energy can create two to four times more jobs per kilowatt-hour in Australia than coal or nuclear. The smaller components of renewable energy can be readily manufactured here. Even wind turbine blades were being manufactured in Portland before the collapse of the former Mandatory Renewable Energy Target in 2006.

You can find more details in my books, Greenhouse Solutions with Sustainable Energy and Climate Action.

To sum up, nuclear power is slow, dangerous, expensive and unnecessary. It’s a diversion from the real solutions to the climate crisis, which are energy efficiency and renewable energy.

[Bobbieo]

1. The major problem is radioactive waste!!! It still has not been cleaned up

from abandoned uranium mines thoughout the West. Where can you SAFELY store it?

[Confusious]

2. YES! that'll work for the United States

Because we're EXACTLY like Australia.

We get the same amount of sun, have the same population, have the same size of territory, etc, etc, etc.

Well, OK. In 1850 we had the same population, etc, etc.

[yourout]

3. Think Thorium...

<http://www.thorium.tv/en/thorium_reactor/thorium_reactor_1.php>

<http://en.wikipedia.org/wiki/Molten_salt_reactor>

Thorium is very abundant and the Molten Salt Reactor has virtually zero chance of a Chernobyl type event.

[kristopher]

4. "Think" being the operative word...

Thorium Fuel: No Panacea for Nuclear Power
(Open Access Document)

Thorium Fuel: No Panacea for Nuclear Power
By Arjun Makhijani and Michele Boyd

A Fact Sheet Produced by the Institute for Energy and Environmental Research and Physicians for Social Responsibility

Thorium “fuel” has been proposed as an alternative to uranium fuel in nuclear reactors. There are not “thorium reactors,” but rather proposals to use thorium as a “fuel” in different types of reactors, including existing light-water reactors and various fast breeder reactor designs.

Thorium, which refers to thorium-232, is a radioactive metal that is about three times more
abundant than uranium in the natural environment. Large known deposits are in Australia, India, and Norway. Some of the largest reserves are found in Idaho in the U.S. The primary U.S. company advocating for thorium fuel is Thorium Power (www.thoriumpower.com). Contrary to the claims made or implied by thorium proponents, however, thorium doesn’t solve the proliferation, waste, safety, or cost problems of nuclear power, and it still faces major technical hurdles for commercialization.


Not a Proliferation Solution

Thorium is not actually a “fuel” because it is not fissile and therefore cannot be used to start or sustain a nuclear chain reaction. A fissile material, such as uranium-235 (U-235) or plutonium-239 (which is made in reactors from uranium-238), is required to kick-start the reaction. The enriched uranium fuel or plutonium fuel also maintains the chain reaction until enough of the thorium target material has been converted into fissile uranium-233 (U-233) to take over much or most of the job. An advantage of thorium is that it absorbs slow neutrons relatively efficiently (compared to uranium-238) to produce fissile uranium-233.

The use of enriched uranium or plutonium in thorium fuel has proliferation implications. Although U-235 is found in nature, it is only 0.7 percent of natural uranium, so the proportion of U-235 must be industrially increased to make “enriched uranium” for use in reactors. Highly enriched uranium and separated plutonium are nuclear weapons materials.

In addition, U-233 is as effective as plutonium-239 for making nuclear bombs. In most proposed thorium fuel cycles, reprocessing is required to separate out the U-233 for use in fresh fuel. This means that, like uranium fuel with reprocessing, bomb-making material is separated out, making it vulnerable to theft or diversion. Some proposed thorium fuel cycles even require 20% enriched uranium in order to get the chain reaction started in existing reactors using thorium fuel. It takes 90% enrichment to make weapons-usable uranium, but very little additional work is needed to move from 20% enrichment to 90% enrichment. Most of the separative work is needed to go from natural uranium, which has 0.7% uranium-235 to 20% U-235.

It has been claimed that thorium fuel cycles with reprocessing would be much less of a proliferation risk because the thorium can be mixed with uranium-238. In this case, fissile uranium-233 is also mixed with non-fissile uranium-238. The claim is that if the uranium-238 content is high enough, the mixture cannot be used to make bombs without a complex uranium enrichment plant. This is misleading. More uranium-238 does dilute the uranium-233, but it also results in the production of more plutonium-239 as the reactor operates. So the proliferation problem remains – either bomb-usable uranium-233 or bomb-usable plutonium is created and can be separated out by reprocessing.

Further, while an enrichment plant is needed to separate U-233 from U-238, it would take less separative work to do so than enriching natural uranium. This is because U-233 is five atomic weight units lighter than U-238, compared to only three for U-235. It is true that such enrichment would not be a straightforward matter because the U-233 is contaminated with U-232, which is highly radioactive and has very radioactive radionuclides in its decay chain. The radiation-dose-related problems associated with separating U-233 from U-238 and then handling the U-233 would be considerable and more complex than enriching natural uranium for the purpose of bomb making. But in principle, the separation can be done, especially if worker safety is not a primary concern; the resulting U-233 can be used to make bombs. There is just no way to avoid proliferation problems associated with thorium fuel cycles that involve reprocessing. Thorium fuel cycles without reprocessing would offer the same temptation to reprocess as today’s once-through uranium fuel cycles.


Not a Waste Solution

Proponents claim that thorium fuel significantly reduces the volume, weight and long-term radiotoxicity of spent fuel. Using thorium in a nuclear reactor creates radioactive waste that proponents claim would only have to be isolated from the environment for 500 years, as opposed to the irradiated uranium-only fuel that remains dangerous for hundreds of thousands of years. This claim is wrong. The fission of thorium creates long-lived fission products like technetium-99 (half-life over 200,000 years). While the mix of fission products is somewhat different than with uranium fuel, the same range of fission products is created. With or without reprocessing, these fission products have to be disposed of in a geologic repository.

If the spent fuel is not reprocessed, thorium-232 is very-long lived (half-life:14 billion years) and its decay products will build up over time in the spent fuel. This will make the spent fuel quite radiotoxic, in addition to all the fission products in it. It should also be noted that inhalation of a unit of radioactivity of thorium-232 or thorium-228 (which is also present as a decay product of thorium-232) produces a far higher dose, especially to certain organs, than the inhalation of uranium containing the same amount of radioactivity. For instance, the bone surface dose from breathing the an amount (mass) of insoluble thorium is about 200 times that of breathing the same mass of uranium.

Finally, the use of thorium also creates waste at the front end of the fuel cycle. The radioactivity associated with these is expected to be considerably less than that associated with a comparable amount of uranium milling. However, mine wastes will pose long-term hazards, as in the case of uranium mining. There are also often hazardous non-radioactive metals in both thorium and uranium mill tailings.


Ongoing Technical Problems

Research and development of thorium fuel has been undertaken in Germany, India, Japan, Russia, the UK and the U.S. for more than half a century. Besi des remote fuel fabrication and issues at the front end of the fuel cycle, thorium-U-233 breeder reactors produce fuel (“breed”) much more slowly than uranium-plutonium-239 breeders. This leads to technical complications. India is sometimes cited as the country that has successfully developed thorium fuel. In fact, India has been trying to develop a thorium breeder fuel cycle for decades but has not yet done so commercially.

One reason reprocessing thorium fuel cycles haven’t been successful is that uranium-232 (U-232) is created along with uranium-233. U-232, which has a half-life of about 70 years, is extremely radioactive and is therefore very dangerous in small quantities: a single small particle in a lung would exceed legal radiation standards for the general public. U-232 also has highly radioactive decay products. Therefore, fabricating fuel with U-233 is very expensive and difficult.


Not an Economic Solution

Thorium may be abundant and possess certain technical advantages, but it does not mean that it is economical. Compared to uranium, thorium fuel cycle is likely to be even more costly. In a once-through mode, it will need both uranium enrichment (or plutonium separation) and thorium target rod production. In a breeder configuration, it will need reprocessing, which is costly. In addition, as noted, inhalati on of thorium-232 produces a higher dose than the same amount of uranium-238 (either by radioactivity or by weight).

Reprocessed thorium creates even more risks due to the highly radioactive U-232 created in the reactor. This makes worker protection more difficult and expensive for a given level of annual dose. Finally, the use of thorium also creates waste at the front end of the fuel cycle. The radioactivity associated with these is expected to be considerably less than that associated with a comparable amount of uranium milling. However, mine wastes will pose long-term hazards, as in the case of uranium mining. There are also often hazardous non-radioactive metals in both thorium and uranium mill tailings.

Fact sheet completed in January 2009
Updated July 2009

[yourout]

6. This conversation is a repeat.

<http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x235481>

I wont be able to change your mind and I doubt you will change mine so I will leave it at that.

[kristopher]

8. Your position is untenable.

I don't care whether I change your mind or not. There is no basis for your claims except nuclear industry propaganda that doesn't withstand even a first cut level of review. When the false claims of the nuclear industry are repeated here we try to meet them with more accurate information that places those claims in the proper context.

The response to the false information will be posted less often if the false claims are not made.

[truedelphi]

12. Thank you for posting that rebuttal. n/t

[kristopher]

14. You are welcome.

[jpak]

5. Someone from NJ has invented a molten salt breeder reactor that uses thorium AND sequesters CO2

it's true

he will save the world - and reap *fabulous* riches and fame.

...at least according to his fauning (ignorant) sychophants (suckers) ...

yup!

:rofl:

[joshcryer]

7. AU is a potential solar mecca.

[kristopher]

9. Yeah, almost as good as Ontario.

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x241951

[joshcryer]

13. Uh, AU could produce way more than 95 GW.

And it could do it with solar thermal rather than photovoltaic.

[kristopher]

15. Yet even Ontario can produce more from solar than the US does from nuclear.

I didn't want people to get the idea that Australia was somehow unique.

[joshcryer]

16. AU is very unique for solar. Ontario is 66% forested.

The people in your study (rightly) had to chose areas that were rocky and barren for the solar potential. In AU actually finding forested areas is the challenge.

BTW, I read the study you linked, and it does not have capacity factor. At 12% their 90 GW becomes a more realistic 10 GW.

[kristopher]

17. You obviously didn't read the study - they deal with hours delivered.

[joshcryer]

18. I wasn't referring to the rooftop PV study.

[kristopher]

19. .

[joshcryer]

20. ROFL

:rofl:

[kristopher]

10. Kick

[NNadir]

11. The operative words are "use natural gas." 100% of anti-nukes, each one dumber than the next

have no idea where to stick dangerous natural gas waste, have no idea how to make dangerous natural gas mining safe or sustainable, and don't give a rat's ass about climate change.

Zero.

None.

Zilch.

The ignorance of nuclear science and nuclear engineering in this diatribe of tired dull arguments that nobody on the planet takes seriously anymore, is abysmal.

One of the most amusing things - were it not responsible for so many deaths it causes is to hear anti-nukes hold forth on a science about which they know nothing.

It's all like hearing Pat Robertson hold forth on evolutionary molecular biology.

Have a nice uneducated rote evening.