Photo: Will thorium save us from climate change?

Many argue that, despite Fukushima and other disasters, nuclear is the best option to reduce carbon emissions fast enough to avoid catastrophic climate change. (Credit: Michael Kappel)

By David Suzuki with contributions from Ian Hanington, Senior Editor

As knowledge about climate change increases, so does demand for clean energy. Technologies like solar, wind, hydro, geothermal, tidal and biofuels, along with energy-grid designs that will help us take advantage of renewables, are part of the equation, as is conservation.

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But many argue that, despite Fukushima and other disasters, nuclear is the best option to reduce carbon emissions fast enough to avoid catastrophic climate change. Because of problems with radioactive waste, meltdown risks and weapons proliferation, some say we must develop safer nuclear technologies.

Even eminent climate scientists like James Hansen claim we can't avoid nuclear if we want to reduce greenhouse gas emissions. Hansen, a former NASA scientist, with Ken Caldeira of the Carnegie Institution, Kerry Emanuel of the Massachusetts Institute of Technology and Tom Wigley of Australia's University of Adelaide, wrote an open letter last year stating, "the time has come for those who take the threat of global warming seriously to embrace the development and deployment of safer nuclear power systems."

What are "safer nuclear power systems"? And are they the answer?

Proposed technologies; include smaller modular reactors, reactors that shut down automatically after an accident and molten salt reactors. Some would use fuels and coolants deemed safer. (Industry proponents argue the low incidence of nuclear accidents means current technology is safe enough. But the costs and consequences of an accident, as well as problems such as containing highly radioactive wastes, provide strong arguments against building new reactors with current technology.)

One idea is to use thorium instead of uranium for reactor fuel. Thorium is more abundant than uranium. Unlike uranium, it's not fissile; that is, it can't be split to create a nuclear chain reaction, so it must be bred through nuclear reactors to produce fissile uranium.

Thorium-fuelled reactors produce less waste, and while some trace elements in spent uranium fuels remain radioactive for many thousands of years, levels in spent thorium fuels drop off much faster. China and Canada are working on a modified Canadian design that includes thorium along with recycled uranium fuel. With the right type of reactor, such as this design or the integral fast reactor, meltdown risks are reduced or eliminated.

Thorium can be employed in a variety of reactor types, some of which currently use uranium — including heavy water reactors like Canada's CANDU. But some experts say new technologies, such as molten salt reactors, including liquid fluoride thorium reactors, are much safer and more efficient than today's conventional reactors.

So why aren't we using them?

Although they may be better than today's reactors, LFTRs still produce radioactive and corrosive materials, they can be used to produce weapons and we don't know enough about the impacts of using fluoride salts. Fluoride will contain a nuclear reaction, but it can be highly toxic, and deadly as fluorine gas. And though the technology's been around since the 1950s, it hasn't been proven on a commercial scale. Countries including the U.S., China, France and Russia are pursuing it, but in 2010 the U.K.'s National Nuclear Laboratory reported that thorium claims are 'overstated'.

It will also take a lot of time and money to get a large number of reactors on-stream — some say from 30 to 50 years. Given the urgent challenge of global warming, we don't have that much time. Many argue that if renewables received the same level of government subsidies as the nuclear industry, we'd be ahead at lower costs. Thorium essentially just adds another fuel option to the nuclear mix and isn't a significant departure from conventional nuclear. All nuclear power remains expensive, unwieldy and difficult to integrate with intermittent renewables — and carries risks for weapons proliferation.

If the choice is between keeping nuclear power facilities running or shutting them down and replacing them with coal-fired power plants, the nuclear option is best for the climate. But, for now, investing in renewable energy and smart-grid technologies is a faster, more cost-effective and safer option than building new nuclear facilities, regardless of type.

That doesn't mean we should curtail research into nuclear and other options, including thorium's potential to improve the safety and efficiency of nuclear facilities. But we must also build on the momentum of renewable energy development, which has been spurred by its safety, declining costs and proven effectiveness.

February 13, 2014

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Aug 14, 2017
5:57 PM

Many of your comments seem to suggest outcomes which you actual speculate as possibilities without any evidence. This is like stating there have been plane crashes since 1950 so flying is not “safe”. There seems to be very little quantification to many of your statements. 30 — 50 years??? I think you will find generation IV will prove very practical, especially the LFTR, and there is no reason to use these in conjunction with intermittent technologies such as solar and wind. As well these reactors produce very little waste and can actually dispose of most waste in storage.

Sep 18, 2015
12:46 PM

As a creator and inventor of smart grid software and supporting technology I see renewables as dead end technologies. Wind -The cost to run and maintain windmills is prohibitive. The sound and the constant strobe effect of the moving shadows creates mental health issues. Solar — If we do the math there aren’t enough raw materials to make enough solar panels to meet our needs. 2. The land use for solar panels to create enough power would require that we starve to death. Large solar farms are as wasteful as growing food to make ethanol. Solar should be used as a support technology for in home appliances. EG. Lights that charge during the day and discharge at night.

Thorium is probably the only source that I can think of that can get us to the point where we can go completely electric and end our dependence on fossil fuels. I can imagine in the future specialized neighborhood reactors to power our homes and distributed transportation reactors powering smart roads where can drive and charge our cars at the same time.

Jun 27, 2015
6:47 AM

We aren’t using thorium reactors because they only work by breeding fuel, and US democrats banned breeder reactors, under the pretext that breeders are an atomic bomb proliferation risk (because they make either uranium-233 or plutonium-239 which could be used to make A-bombs). I guess we’ll have to live with global warming. No solution’s perfect. Sorry for being so flippant, but taking this seriously just makes me depressed. Your renewable energy world with its hypothetical (never to exist) mass energy storage system is a fairy story.

May 09, 2014
2:59 PM

If the objective of sustainable energy is to provide humanity a source of abundant electricity and transportation fuels that are carbon neutral at an economical advantageous point. Then thorium as a source of energy conversion in breed-burn in place nuclear modular reactors is probably the best alternative. In particular the Liquid fluoride thorium reactor LFTR with a dual salt combination (Li and Be) are very beneficial.

Thorium as a sustainable fuel in breed-burn reactors at current and anticipated energy utilization levels will be available to humanity for the projected time the earth will be able to sustain life (a few billion years) as pointed out by Bernard L. Cohen in 1983. Even the sun will stop shining at one point in time.

Electricity can be produced very efficiently with a super-critical carbon dioxide Brayton turbine from the heat produced by the thorium reactor. And methanol can be produced from carbon dioxide capture directly form the atmosphere and hydrogen from water separation in an electro-thermal cycle for carbon neutral transportation fuels. The technologies have been proven. They work. What remains is a commercialization process that is safe, cost effective and in line with the political imperatives.

The deployment of modular ( ~100 MWe and ~10 MWe) LFTR(s) that can sustain humanity’s energy needs (and wants) can be economically achieved is less than 20 years if they were made a priority. China in particular has made a commitment to commercialize the LFTR technology. China’s time table is consistent with a 15 to 20 year deployment.

Liquid fluoride thorium reactors LFTR provides an implementation that is passively safe and with in-place handling of all nuclear active elements produced in the core. No need for external repositories for the nuclear active elements. Farther more, because of the deeper burn of the nuclear fuel in LFTR the amount of nuclear active waste is greatly reduce. The nuclear active elements produced are also of much shorter time duration. Hundreds (100’s) of years rather than hundreds of thousands of years (100,000’s).

The proliferation of nuclear weapons grade material is also greatly reduced by the in-place handling of all nuclear active elements. An open accountability of all nuclear active elements is easily maintain in place. Farther U233 which is the primary fissile element produced in LFTR represents a much more difficult path to nuclear weapons than P239 or U235. As human history shows. Proliferation of nuclear weapons is not going to be stopped by keeping a beneficial technology from becoming commercialized. Proliferation will be stopped by humanity’s decision not to proliferate nuclear weapons.

Solar, hydroelectric, geothermal and win power have environmental impacts as well. In the case of solar photovoltaic cell poisonous chemicals are used in their manufacturing. In the case of solar and win there are drawbacks of diffusion and intermittent electrical generation. Hydroelectric and geothermal are not sufficiently abundant on earth’s surface to satisfy humanity’s needs. Solar, win, geothermal and hydroelectric have niche application and they can contribute a fraction of humanity’s energy needs but they cannot economically provide the total answer.

The facing out of nuclear energy in Europe is having the consequence of increasing the use of coal as the fuel for generating electricity. The demand for energy carriers, electricity and transportation fuels is not going to be reduced if the standard of living for humanity is to increase. Energy use is directly proportional to the standard of living.

With a projection of 10 billion human beings on earth, in the near future, we face an opportunity to make prudent technological choices to supply the energy resources in abundance to a vibrant civilization. Or we can shrug in fear and let the coal, gas and oil resources take us to a catastrophic outcome. In hopes that solar, win, hydroelectric and geothermal somehow will save us from that catastrophe.

Mar 11, 2014
6:32 PM

It’s just sad to see an “article” like this dismissing nuclear energy based on what is obviously not more than 15 minutes of wikipedia research.

Feb 23, 2014
12:37 PM

The private consortium that will manage the decommissioning of the UK’s decaying Magnox nuclear reactors won’t be made to bear financial responsibility in the event of a radioactive incident. Taxpayers will have to pick up the tab instead.

Private contractors will be indemnified by the government, despite concerns that exempting them from financial liability for nuclear incidents could prove a disaster for the taxpayer, the Guardian reports.

Feb 18, 2014
4:00 PM

This doesn’t sound like the living off the surplus the sun provides mantra we are used to hearing from DSF?

Why try to placate those who don’t believe in changing their habits of copious consumption?

Feb 17, 2014
9:38 PM

This is utter nonsense as the only way we can save our kids’ futures is by MAKING THE SUN OUR SOLE ENERGY-POWER SOURCE. I urge Mr Suzuki to check my previous postings here and elsewhere stating that OUR KIDS WILL ONLY SURVIVE BY MAKING THE SUN OUR SOLE ENERGY-POWER SOURCE!!!!!!!!! Everything else being claimed from “clean” fossil fuels to nuclear power results in adding more trapped energy into our environment to end up slowly boiling our kids off earth. Again Mr. Suzuki is missing the boat on how we have to perserve the future for our kids. AGAIN WE HAVE TO MAKE THE SUN OUR SOLE ENERGY-POWER SOURCE, and I have outlined how we can do this in several e-mails to Mr. Suzuki. James Singmaster, III, Ph.D., Environmental Chemist, Ret., Davis CA

Feb 16, 2014
12:21 PM

Like it or not — we will have to continue using nuclear power in some way for the forseeable future. There is no single “fix”. But where is the common sense? It is unfortunate that countries like Japan who desperately need to use nuclear power are located in very unstable and undesireable places geographically. All nuclear tragedies are horrendous but there are places in the world where there are more “reasonable” locations. The global community needs to find a way to balance access to energy in spite of large corporations and there ever more powerful bottom line.

Feb 15, 2014
1:49 PM

I am a person seriously affected by second-hand fragrance and am suffering at work and in most public places. I may lose my job. If we think about the amount of fragrance contamination we encounter in public places such as schools, church, governmental offices, medical facilities and at work

Feb 15, 2014
1:12 PM

Salmon died upstream in Suomi (Lapland) Finland. The water upstream is perhaps radioactive alike the upstream water in Greenland. Salmon was the Bears staple food. Bears are consequently extinct in Suomi. (Strange how they build to this day (1960th) Salmon traps in upstream waters of Suomi .)

Feb 14, 2014
9:47 PM

Is anyone close to getting Scalar energy to produce enough energy for us? I have also heard that it may one day be used for communications. Just think, replacing cell phone radiation with a safe way to send data.

Feb 14, 2014
12:30 PM

Hello David,

I am a Canadian snowbird and, in Hawaii, we are faced with two poisons daily — those from GMO pesticides and Chemtrails.

Can you please comment on these subjects in the future?

There are about four GMO companies on the garden island of Hawaii, which is called Kauai. There is an active, local environmental group here called “Kauai Rising”. I am sure they could benefit from your wisdom.

Many thanks,
Ariana Sheran from Saskatoon

Feb 14, 2014
10:05 AM

Nice to see that you people are at least discussing nuclear power. I am a former strident anti-nuclear person that couldn’t help but notice some very influential people that I respect were either pro-nuclear or reversed their position. These include George Monbiot, Jim Hansen, Bill Gates and even the Dhali Lama to name a few. After reading several books, including Cauldicott, I slowly reversed my position. It’s a complex subject and poorly understood by the public (not to mention most environmentalists). What a shame. The safe development of this technology in the hands of good people is so obviously superior to anything we are currently doing. I guess that it is why it is sometimes called the technology of Angels. The problem is the lack of awareness and misinformation about this evolving technology. There is little doubt if we were to focus globally (incl. the U.S., a must) on developing both Thorium reactors and IFR’s (such as ‘Prism’ from the Argonne research) at the same time continue to build the newer design Gen3 reactors, development of this technology would occur much faster. Remember the new IFR’s will be able to use up old style reactorr spent fuel leaving little waste rendering it harmless in the low hundreds of years instead of thousands of years. Yes there are still questions and issues to be resolved but if one looks honestly and objectively at the evolving technology, those issues are being resolved. Please keep this discussion alive, we need to look more seriously at this option.

Terry Gay

Feb 14, 2014
9:30 AM

This is the worst idea DSF has presented to the public since it joined Cadbury on its junk food campaign as a way to raise funds. Just as the solar industry is coming of age we have DSF taking us back to the nuclear option. Why don’t you promote the oil palm plantation indsutry as well as a way to stop climate change? Seems DSF needs some serious progressive policy advisors as clearly the Cadbury Junk food venture and now the Thorium advocacy campaign are examples of a lost leadership at DSF.

Feb 14, 2014
7:33 AM

FYI, the reason the LFTR was scrapped was because it could not produce weapons grade plutonium.

Also a large scale reactor has been tested and ran for 7 years at the oakridge labs in the 60s.

Our current problem is excessive carbon being released. I would rather see thorium power over any hydrocarbon fueled power.

Feb 14, 2014
4:31 AM

Yeah we should curtail all research they’ve had enough money and time it isn’t like we’re hearing a new story just the same old thats had some spin put on it.

Renewables, costs are continuing to decrease and efficiency increasing. Issue isn’t can it be done,the issue is corruption in government by the fossil fuel industry only need to look at West Virginia, Alberta (everywhere) to see the sad truth.. God I’m a Negative Nancy!!

Feb 13, 2014
4:47 PM

This article pre supposes that we need lots of energy. We only need so much energy if we are to continue the economic growth game. Let’s stop that first and then recalculate. IF climate change is related to carbon emissions then the only growth capable of reversing it is real growth ie trees…carbon capturing reforestation. Please get this on your table.

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