Posted by Mark Halper

University of California Berkeley nuclear engineering head Per Peterson is a fan of molten salts and other alternative nuclear. He’ll chair the ANS proceedings in San Diego. Above, he examines a model of a     pebble bed reactor in this photo from KQED Quest.

When we launched our blog here at the Weinberg Foundation in late September, we nicknamed it The Thorium Trail and pledged to travel the world spotting the emergence of alternative, safe nuclear technologies such as thorium.

And travel we have, as our path has included a real world landing last week in Shanghai – where we journeyed from our London base – as well as virtual stops in Norway, South Africa, Jordan, and the United States. Through the wonders of the Internet, we’ve skimmed uranium mines in Namibia and Australia, and have brushed up against oil sands in Canada, where small reactors could help cut fossil fuel-driven heat use.

We’re not resting.  We can’t.  Not when the world will need safe nuclear as a base load power source to help stem the effects of fossil fuel induced climate change that dramatically took centre stage a week ago when Hurricane Sandy clobbered New York and New Jersey.

Today, we turn our attention to San Diego for a quick preview of the 5-day American Nuclear Society’s annual winter conference, which kicks off this Sunday, Nov. 11.


Have a look at the agenda here – click on the page’s “official program” link. On the surface, there’s not much going on related to thorium, the alternative to uranium that if run in the right type of reactor offers all manner of advantages over today’s nuclear plants: it’s safer, more efficient, meltdown proof, produces less waste and it reduces the weapons proliferation threat.

In the impressively busy 60 pages, the word “thorium” appears only once.

That is disappointing – shameful, really –  but it’s not a surprise. Of the conference’s eleven sponsors, seven are U.S. utilities – not known as the most progressive bunch when it comes to their nuclear power. The top two “platinum” backers are utility behemoths Duke Energy and Southern California Edison. The old guard is not going to shout about a new fuel like thorium that could disrupt its comparatively comfortable – and time honoured – uranium value chain.

Yet the conference will thankfully be chock full of sessions on alternative nuclear reactor designs (albeit not alternative fuel).  After all, ANS is assembling this year’s conclave under the heading Future Nuclear Technologies: Resilience and Flexibiity.

By inference, thorium will be in the collective consciousness, as many of the formal sessions will focus on technologies that could be optimized by using thorium rather than uranium – technologies such as such as molten salt cooling systems and high temperature reactors.


Let’s start at the top.  The conference’s general chair is University of California Berkeley  nuclear engineering department head and professor Per E. Peterson. Peterson has a rich background researching many advanced nuclear technologies, and his UC Berkeley bio notes that “currently his research group focuses primarily on heat transfer, fluid mechanics, regulation and licensing for high temperature reactors, principally designs that use liquid fluoride salts as coolants.”

I’ve added the boldface type in that last sentence because it bears noting that one of the most promising alternative designs for a thorium-fuelled reactor is indeed one that runs at a high temperature while cooled by liquid fluoride.

So there you go. The conference chair – the man running the San Diego show – has a keen interest in a thorium enabling technology, if not in thorium per se.

In fact, high temperature, molten salt reactors are the subject of the U.S. Department of Energy’s collaboration with China’s Chinese Academy of Sciences. CAS, as I wrote from Shanghai last week, is developing a liquid thorium molten salt cooled and fuelled  reactor (TMSR). The completion date has slipped, and China is welcoming expertise from the U.S., which developed a TMSR at Oak Ridge National Laboratory in the 1960s under the direction of Alvin Weinberg.

DOE has said its interest in the collaboration focuses on the liquid coolant applied to high temperature reactors, but that unlike its Chinese collaborator, it is not currently investigating liquid thorium fuel.


It’s not entirely clear why not, but MIT research scientist Charles Forsberg, who will be speaking several times in San Diego on fluoride coolants, might be able to provide an answer.  Forsberg is part of the DOE/China collaboration. DOE has tapped MIT, Peterson’s UC Berkeley, and the University of Wisconsin as partners in the collaboration which includes DOE labs Oak Ridge and Idaho National Laboratory.

Pittsburgh’s Westinghouse is serving as a commercial adviser on the same collaboration. So it seems no coincidence that when Forsberg and Peterson combine on Thursday in San Diego to give eight presentations related to salts and high temperatures, they will do so under a track chaired by Westinghouse nuclear engineer Art Wharton. It’s entitled Advanced Reactors.

Westinghouse, which does not like to publicly discuss its alternative reactor work, has had a hand in many of the sessions planned for the week, including those focused on small modular reactors, and one focused on a travelling wave reactor (the fast reactor that Bill Gates is building, although some say Gates has abandoned the “travelling wave” for a “standing wave” – more on that another time).

Outside of considerable of sessions dedicated to fluoride salt coolants, there will be plenty of talk surrounding other alternative reactor technologies.


Fast reactors like San Diego-based General Atomics’ energy multiplier module are on the docket (GA is a co-sponsor of the conference which is taking place in its back yard).

So, too, are modular reactors – the small designs that could represent reduced upfront costs, provide electricity to remote off-grid regions and workplaces, and serve as industrial heat sources.

Equally, high temperature pebble bed reactors (PBRs) will take the spotlight in several technical sessions. Again, the discussion will not revolve around thorium. That’s an unfortunate oversight given that thorium could optimize pebble bed operations – a fact not lost on South Africa’s Steenkampskraal Thorium Ltd. which, as I wrote recently, is assembling a group of customers to help finance development of its gas cooled thorium fuelled PBR.

Any “future nuclear” technology conference would not be complete without fusion tracks, and the ANS conclave will have that as well – fusion is one of Peterson’s research subjects. The fusion discussions will include a look at tritium in both fusion – where it is a fuel – and in fission – where it is a waste, or byproduct. MIT’s Forsberg will be among the experts addressing the subject.

The one mention of thorium in the agenda? A 25-minute talk scheduled Wednesday morning by Terry Kammash from the University of Michigan, entitled Hybrid Thorium Reactor for Safe, Abundant Power Generation. It’s part of a group of presentations falling under the general heading Reactor Physics Design, Validation and Operating Experience and including a talk on liquid fast reactors.


For a broad overview of all of these technologies, ANS president Michael Corradini will chair a Tuesday afternoon forum entitled Ten Years Since the Generation IV Roadmap: Progress and Future Directions for New Reactor Technologies, followed logically by a Wednesday morning look at what the next 10 years hold.

A session entitled Telling the Nuclear Story Using Online Video and Broadcast should remind every one that it behooves the nuclear industry to effectively communicate its advantages to the public, especially in the wake of the Fukushima tragedy. Panelists will include Cara Santa Maria, the host of Huffington Post’s Talk Nerdy to Me.

As I’ve wandered onto the “PR” subject, here’s some free advice to ANS: you’ve done a good job assembling experts on many promising forms of alternative nuclear. It is beginning to feel like some of these alternatives could soon get  a more serious look from investors. Let’s hope so. But you gotta talk thorium, too.

Photo: Gabriela Quirós for KQED Quest.

Note: We won’t be in San Diego, but we’ll have our ear to the ground. Will you be there? Feel free to send your impressions. You could comment below, or use the “contact” tab above. Thank you –MH.


  1. William R Knight says:


    I am a physicist / physical oceanographer by training. After reading “Superfuel – Thorium…” by Richard Martin and thinking about it all for a week, I am now totally committed to LFTR science and technology. My question to the audience: Where could I re-enter graduate school in such a program where my age would not be considered a detriment?

    Thank you

    Bill Knight

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