This group brings together the best thinkers on energy and climate. Join us for smart, insightful posts and conversations about where the energy industry is and where it is going.


ThorCon's Nuclear MSR Design Gains Momentum

Fall 2017 has been a watershed of progress for ThorCon, a startup developing liquid fuel fission power plants. The company is working to implement its molten salt reactor (MSR) technology first in Indonesia.

The Argonne National Lab has teamed up with ThorCon to apply for DOE grants that would support the development of ThorCon’s advanced MSR technology. One of the proposed projects would have Argonne apply its new high-fidelity simulation tools to ThorCon’s reactor design See also this technical summary of its MSR reactor (PDF file).

ThorCon employs a moderately high energy density resulting in a short (4 year) moderator life. A ThorCon plant is made up  of one or more 250 MWe modules. Each module consists of two sealed Cans. Each Can houses a 250 MWe primary loop including a  Pot (reactor), pump, and primary heat exchanger. The two Cans are duplexed. At any time, one Can is operating and the other is in cool-down or stand-by mode. The plant is designed so that the change out of a cooled-down Can is safe and quick.


Meeting at Argonne.  From left: Cherria Supit (secretary KEIN), Lars Jorgensen (CEO of ThorCon US), Bo Feng (ANL reactor design expert), Tanju Sofu (ANL Program Manager), Florent Heidet (ANL Section Manager), Zulnahar Usman (head of KEIN delegation), David Devanney (CEO of ThorCon International), Bob Effendi (KEIN), Deltadi Nurwijayanto (KEIN).

thorcon at argonne

KEIN delegate meeting with Argonne MSR team chaired by Dr Tanju Sofu (sitting in front, brown jacket) Others are members of the workgroup from ANL and Thorcon.


First Investor

ThorCon’s first round of funding has been achieved. One of the investors, Dr. Gary Bergstrom, the founder of Acadian Asset Management, states;

“I was impressed by the extraordinary engineering abilities of the team as well as the project’s potential to make a dent in the climate change problem. Over my career I have been extensively involved with investing in emerging economies and I believe that many are promising markets for ThorCon’s clean, non-intermittent, and low cost (under 7 cents/kWh) electric power. It also offers dramatic benefits in facility placement options and safety versus other alternatives.”

Indonesian Delegation Visit

In early November, a delegation from Indonesian President Widodo’s special advisory Council on the National Economy and Industry (KEIN), made a visit to the United States to carry out due diligence on molten salt reactor (MSR) technology and on the ThorCon design.

The delegation was escorted by ThorCon on visits to the Braidwood Nuclear Generating Station, the Argonne National Lab, the Oak Ridge National Lab, and the Office of Nuclear Energy of the Department of Energy in Washington, DC.

Mr. Zulnahar Usman, the chairman of the delegation, summarized the trip as “an unqualified success. Our meetings and discussions with various nuclear and molten salt reactor experts in the United States have confirmed the safety and viability of the MSR technology.”

He added, ” The ThorCon power plant has also been confirmed as an excellent design whose stated schedule and costs are doable. I am going to strongly recommend to President Widodo that the Government add the Thorium MSR technology to the country’s energy mix.”


Meeting at ORNL.  From left:  Dr. David Holcomb (ORNL), Dr. Gary T. Mays (ORNL headof MSR program, Mr. Zulnahar Usman (head of KEIN delegation), Mr. Bob Effendi (KEIN), Lars Jorgensen (CEO of ThorCon US), Ms. Cherria Supit (KEIN).


DOE Office of Nuclear Energy Meeting

One of the highlights of the delegation’s US trip was a meeting  the DOE’s acting head of nuclear energy, Mr. Ed McGinnis, who showed strong interest in Indonesia’s  progress towards nuclear power.

Mr. McGinnis and Mr. Usman agreed that the two countries would take steps to increase cooperation in support of Indonesia’s nuclear plans with the understanding that a ThorCon demonstration power plant would most likely be Indonesia’s first step.


Meeting at DOE. From Left:  Tom Blees (SCGI), Zulnahar Usman (head of KEIN delegation), Ed McGinnis (DOE head of nuclear power), BobEffendi (KEIN), Lars Jorgensen (CEO of ThorCon US)


Cost of Thorcon Power in Indonesia

At a recent meeting hosted by the Deputy Minister of Energy in Indonesia, a day long review was undertaken by the various stakeholders in the Government and private industry regarding adding nuclear power to the country’s energy system.

A comparison of all offered sources of nuclear found ThorCon’s power to be 4 to 5 cents per kWh lower than the competition and the only clean source of non-intermittent power that was competitive with coal.

PLN, the national utility company, expressed its willingness to buy nuclear power if it was under 7 cents per kWh.  ThorCon’s willingness to provide power at this level was made clear to the Deputy Minister who expressed a preference for this low-cost option while at the same time acknowledging its unproven nature at commercial scale.

Original Post

Dan Yurman's picture

Thank Dan for the Post!

Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.


Bob Meinetz's picture
Bob Meinetz on Dec 9, 2017 5:04 pm GMT

Dan, as encouraging as it is to see cooperative nuclear ventures making progress around the globe, a review of ThorCon’s engineering schematic is not encouraging.
As of 2016, the ThorCon model depends on not one, not two, but three independent salt loops/heat exchangers, from which the company predicts an overall thermal efficiency of 44%. If they can pull it off reliably, it will be a miracle of thermal management – forget the nuclear part.

Hopefully success of an initial prototype will quickly lead to followups with vastly improved mechanical efficiency. As it stands right now: too many moving parts will make it a maintenance nightmare (I look forward to Robert Hargraves, who is associated with the project and has commented here before, explaining why I’m wrong).

The ThorCon power plant has also been confirmed as an excellent design whose stated schedule and costs are doable.

Stated schedules and costs are always doable. It’s the actual ones which cause problems.

Roger Arnold's picture
Roger Arnold on Dec 9, 2017 9:14 pm GMT

NextBigFuture also has a short article about Thorcon (here). It focuses on the company’s shipbuilding roots and how shipbuilding methods will be used to build the molten salt reactors. Looks very promising.

The NBF article was abstracted from a 34 page PDF (here) at Thorcon’s web site.

Leo Klisch's picture
Leo Klisch on Dec 9, 2017 9:56 pm GMT

“ThorCon uses an 8 year fuel-salt processing cycle. The used salt is allowed to cool-down in the non- operating Can for four years, eliminating the need for a separate, vulnerable spent fuel storage facility. The salt is then shipped to a specialized processing facility. All fuel waste handling problems are shifted from the plant to this facility. This processing will return almost all the uranium and eventually most of the plutonium in the salt back to the system, where most of these actinides will be fissioned.”

I would like a more complete picture of the waste life cycle both qualitatively and quantitatively.

Leo Klisch's picture
Leo Klisch on Dec 11, 2017 8:46 pm GMT

Seems a better idea to repower existing nuclear plants that are ready for decommission. Would be easier to add to existing fuel waste and easier politically.

Dan Yurman's picture
Dan Yurman on Dec 12, 2017 2:40 am GMT

I’ve asked Thorcon for this information as well but my more significant concern is the front end of the fuel cycle. What supplier will fabricate the fuel for them?

Engineer- Poet's picture
Engineer- Poet on Dec 12, 2017 3:48 am GMT

What fabrication?  The fuel is a molten salt.

Bob Meinetz's picture
Bob Meinetz on Dec 12, 2017 5:02 pm GMT

wind, there is exactly one U.S. power reactor which is “ready for decommission”: Three Mile Island Unit 2. It was destroyed forty years ago after a loss-of-coolant accident caused a partial meltdown.

The others are constantly upgraded. When parts break or get old, they are replaced. The only other reason to decommission a functioning U.S. plant is to placate irrational public fear – and with a cost of $billions of dollars, it would be far cheaper to pay for psychological counseling.

Engineer- Poet's picture
Engineer- Poet on Dec 13, 2017 4:01 am GMT

TMI Unit 2 had no damage to the reactor pressure vessel, and the core was not all that difficult to clean out.  Yes, even with hand tools.  It was carried on the books of its utility as a working asset for years after the accident, and the NRC should have let it refuel and restart.  It was an enormous waste and a criminally discarded opportunity.

Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »