Posted by Stephen Tindale

“I cannot really complain too much about solar utopians: their dreams are noble and ought to be encouraged. On the other hand, when these dreams of solar utopia are used as political instruments to eliminate the nuclear option, I believe it is most important to object.”

Alvin Weinberg, ‘Toward an acceptable nuclear future’, 1977.

I am a former renewable energy utopian – though, since I live in the UK, I am more excited about wind power than I am about solar. I spent 20 years campaigning against nuclear, the last 5 of them as head of Greenpeace UK. I protested outside nuclear power stations. Then I realised that I had been wrong; that renewable energy cannot expand quickly enough to phase out fossil fuels and protect the climate. I concluded that opposition to nuclear power is not compatible with any attempt to control climate change. And, because many of my former colleagues in green groups were continuing with anti-nuclear campaigns, I too felt that it was important to object. So for the last 6 years I have been speaking out in favour of nuclear power, and was delighted last month to start working for the Alvin Weinberg Foundation.

Alvin Weinberg was not only a world-renowned nuclear scientist, but also one of the world’s first climate campaigners. He warned of the dangers of increased carbon dioxide concentrations in the 1970s; over a decade before James Hansen’s historic Congressional evidence in 1988. (That is not in any way intended to downplay Hansen’s immense contribution to climate science or, indeed, to campaigning.) Weinberg also spoke out against the dangers of technology tribalism. We need to use every tool to mitigate the climate and energy crises. We do not need nuclear or renewables; we need nuclear and renewables. That is even more strongly the case today in 2015 than it was in the 1970s.

In the 1977 paper quoted above, Weinberg speaks of the need “to set the nuclear ship back on course”. Thirty -eight years later, it definitely needs to be set back on course again, particularly in Europe. The European Pressurised Reactor (EPR) that is supposed to be constructed in the UK may well get abandoned; EDF have not yet taken a final investment decision, and the EPRs being built in France and Finland are well over time and over budget. The latest in a long line of problems is that Areva have used the wrong type of steel at the EPR site in France, and the steel is already encased in concrete.

The EPR is a very complex design. Other existing nuclear reactor designs (so-called generation 3 or 3+) are less complex and need to be built, because they are proven, demonstrated and ready to go. However, more advanced designs must also be researched, developed and demonstrated. This should include both Integral Fast Reactors and Molten Salt Reactors (MSRs), the technology which Weinberg himself pioneered at Oak Ridge in the 1960s. MSRs have many potential benefits over current nuclear reactors:

* The plant can operate at near atmospheric pressure. The fuel salt used in MSRs has no chemical reactivity with air or water. So MSRs cannot explode.

* The liquid salt returns to a solid form at ambient temperatures. This, combined with installed passive safety systems, would automatically shut down advanced reactors avoiding future situations like  Fukushima and Chernobyl.

* Some advanced reactors could be fuelled by existing nuclear waste from conventional nuclear reactors. This ‘waste’ still contains over 90% of the energy that was in the uranium, so can be used many times as fuel. At the end of the process these advanced reactors would still produce some waste, but much less by volume than the waste produced by a conventional nuclear plant.

* Certain next-generation reactors can use plutonium as fuel. The UK has the world’s largest stockpile of plutonium, a result of two decades of reprocessing and failure to use mixed-oxide (Mox) fuel.

* Advanced reactors could be very fuel efficient – up to 75 times more electricity per ton of fuel than an out-dated conventional light-water reactor.

*Next generation reactors could be designed to be small and modular (producing up to 300 megawatts) which would suit power needs in remote locations. Compact versions of MSRs could be built in a central factory and assembled on site. This would reduce costs.

* Modular reactors could be constructed adjacent to industrial sites so that waste heat from the reactor could be used for heat-intensive processes such as desalination or the production of aluminium, cement, ammonia and synthesised fuels.

* Some advanced reactors are ideally suited to the sustainable production of medical isotopes, used for scans and to treat cancer. These isotopes are currently in short supply.

* Most next generation reactors would use approximately 97% less water than conventional nuclear reactors.

The Alvin Weinberg Foundation is committed to highlighting these benefits, to politicians and the public, and seeing the potential of advanced nuclear power realised. There are companies seeking to build prototype MSRs in the UK. If the EPR is abandoned, a sensible reaction by the new British government would be to support an advanced nuclear technology demonstration project in the UK.


  1. Heiner Thiel says:

    I’m excited and relieved that there are still some sane pepole in this world! I very much hope that these new reactor concepts can and will be built in Europe! Living in Germany, I have very little hope though, that this will be done here: too many well meaning but ill-informed people… :((

    I wish you all the best!!


    Heiner Thiel

  2. John Longenbaker says:

    I’m on board the LFTR bandwagon! Alvin Weinberg was on the right track. ORNL had a working demonstrator reactor of this type. We don’t need more weapons grade plutonium. Thorium has so much to offer. Let’s do it, China and India are. Why buy their technology in the future. Come on, America. Wake up to this promising technology!

  3. Jim says:

    What about the small modular reactor from Nuscale? As far as I can tell it cannot melt down or explode, and is set to be submitted for approval by the NRC in 2016.

    Surely it would have better economics than the EPR being built in the UK by EDF?

  4. Gordon McDowell says:

    Stephen, I’m looking to collect video testimony to this effect. Any chance you can coordinate with me? Just shooting something simple on an iPhone would suffice (if that’s all you have access to), or I’ll coordinate with a video volunteer in your area to do a better capture.

  5. Alex says:

    Given that there are designs of Molten Salt Reactors that could be built within six years – or shall we say the late 2020s if you include the regulatory process and a lot of slack, does it still make sense to support the Gen III deployments?

    Especially given the fact that Gen IIIs are negotiating prices of £80-90/MWh, whereas MSRs can deliver at under a half of that.

    Or do we spread our bets and say yes to Gen III and even more “yes” to MSRs.

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