India: A Hotbed Of Molten Salt


The world is full of surprises isn’t it?  Well, I’ve just experienced quite a big one. I’ve just returned from the most amazing meeting of the minds in Mumbai – the Conference on Molten Salts in Nuclear Technology hosted at the Bhabha Atomic Research Centre (BARC).BARC is the sprawling campus – more akin to a small city – where a majority of India’s research into nuclear power takes place, on the outskirts of the heaving metropolis.

It is a true microcosm of India really: a mix of impressive modern buildings and ranging down to what Western eyes, at least, might call slums. Through it all, no one can dispute the impressive work that has taken place here over the decades.A little background first. India has been heavily involved in nuclear power research since the 1960s – much of the time on its own, since the world discovered to its disappointment that the country was also working towards nuclear weapons.

With its testing of a warhead in 1974, India became a sort of pariah, with most other countries cutting off all nuclear ties – including civilian nuclear power.  This has been changing significantly over the past several years.But since its very early days when led by BARC’s namesake, Homi Bhabha (the so-called “father of India’s nuclear programme”) India has had a very ambitious civilian nuclear power development vision.Given India’s lack of easy to obtain uranium and its abundance of thorium, the long term plan has been to start first with uranium in heavy water reactors and then put those reactors’ plutonium along with thorium into a subsequent small fleet of sodium cooled fast breeder reactors.

These fast reactors would produce U233. This U233 would then be used to start a large fleet of a more advanced breed of heavy water reactors that would operate a closed, self-sustaining cycle of thorium and U233, a very tough job as the solid fuel would need to be processed frequently.


The country’s steadfast commitment to this 3-stage, heavy water, to sodium cooled, to advanced heavy water evolution has been challenging, to say the least. India has built few reactors totaling only 4.8 GWe and nuclear power is unfortunately only a small fraction of India’s power production  – the majority comes from coal.Because of this seemingly engrained roadmap, many of us molten salt  advocates – and yes, I am one – didn’t expect to convince India of the merits of molten salt reactors even though MSRs are well known for their ability to breed fuel using thorium, or in even simpler forms, for their ability to use uranium many times more efficiently than do water cooled reactors.

And now, for the surprise, which has come to me in waves over the last few months, starting last summer when the conference organizers asked me to give a plenary talk. I was more surprised several weeks ago when the list of scheduled talks surfaced with 11 of the 25 presentations by Indian researchers. And then, the best surprise of all: after three great days of talks, I am truly impressed with the quantity and quantity of Indian work on the subject.

I left Mumbai with a conference proceedings of over 50 papers, two thirds of them by Indian authors. There were a couple dozen of us contributors from outside India including Europe, the U.S., Canada and Japan. A representative from the Chinese Academy of Science’s MSR program, Zhimin Dai, was to present but visa issues held him up.Speaking of which, at first glance someone might speculate that India’s new involvement in MSR research might be reactionary to China’s recent major foray into the field. Whether that was the spark or not, it was very evident that a great pent up interest has been released in India.I have quite literally never seen such a large gathering of engineers and scientists with such an interest and more importantly, knowledge of molten salt technology.


This interest goes back to the 1970s when they directly contributed to Oak Ridge’s MSBR (molten salt breeder reactor) programme and we got to hear from many of those who contributed. From these Indian “old boys” I heard the same lament one hears from Oak Ridge’s “old boys” of what a shame it is this technology was left behind. I also heard the same enthusiasm for its current renaissance.Indian researchers presented a variety of work on fluid fueled molten salt reactors but also on the idea of using similar molten salts as coolants – but not fuels –in what are known as FHRs (fluoride salt cooled high temperature reactors).

The FHR concept originated in the U.S. some ten years ago and is also a big part of China’s program.  Some MSR advocates might malign this “salt cooled” work as some sort of half measure in comparison to “salt fueled” MSRs.While FHRs lack the extensive list of potential benefits that MSRs can claim, some researchers view FHR as a simpler first step. I see the merit of FHR design and have ideas in that regard myself but view it as a parallel path with MSRs, certainly not FHR first, true MSRs later.As the audience was fully aware of MSR’s background and promise in terms of safety, cost, resource sustainability and long lived waste reduction I was able to focus on MSR reactor design.

I presented on choices including my work on the “tube within tube two fluid MSR” which looks to solve the “plumbing problems” that led ORNL to abandon the promising two fluid approach in 1968. I also provided a few hints towards a new design concept I hope has much potential, and for which I have filed patents.


Much of my presentation, though, focused on a simpler route forward through an MSR design which is known as a converter reactor and in particular a form of converter known as a denatured molten salt reactor (DMSR, with “denatured” meaning that any uranium employed is useless for weapons fabrication).This approach uses both mined uranium and thorium together, or simply uranium alone. It is not a breeder like many MSR concepts but results in a much simpler reactor with far less R&D; especially since it skips any sort of fuel processing.

The minor drawback is that it requires small amounts of annual uranium in order to top up the fuel cycle. But the amount is just a fraction of what conventional reactors require. A DMSR operator would only need to spend about 0.05 cents per kwh on uranium, and would not be adversely affected by any rising uranium prices either – not even by, say, a ten-fold increase over today’s low price level.The message: MSRs are not just the best “thorium” reactor, they are also the best “uranium” reactor.

It really is the engine, not the fuel that is the story. Come for the thorium, stay for the reactor as my tag line of late has been.I’m back in Canada now, with Mumbai and my gracious hosts at BARC and the constant din of car horns still very much on my mind. And I can’t help but feel the world is a lot closer than it was before this conference to a future with a sustainable and affordable source of energy. It’s a good feeling, a good feeling indeed.

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