ThorCon Tries to Scale Down Nuclear
Jack Devanney is an MIT-trained engineer who taught in Cambridge before becoming involved in the ship-building industry. He spent 25 years dealing with designing, building, and operating oil tankers, including the largest double-hull tankers every built.
Then in 2011 he read an MIT Technology Review article about how the world was going to have to add 1250 gigawatts of electrical generating capacity over the next 20 years just to keep up with demands of a growing mankind. MIT figured this would amount to 1199 new coal plants worldwide.
Facing this kind of future, Devanney set about trying to design a safe nuclear reactor that could be manufactured cheaply in order to meet this demand. He enlisted some of the best engineers and physicists in the country to the task.
The result was ThorCon, a nuclear power plant with 250 megawatt modular reactors that can be fabricated in a shipyard, barged to a site and assembled. “The byword for this project is NNT - ‘No New Technology,’” says ThorCon’s website. The company has just taken existing technology and applying some tactics learned from the ship-building industry to make it more efficient.
The Thorcon reactor is basically a scaled-up version of the very successful Molten Salt Reactor Experiment that was carried out in the 1960s. Instead of being fashioned into solid fuel rods, which can melt down when overheated, the uranium fuel is dissolved in molten fluoride salts. “This means if the reactor overheats for any reason, ThorCon will automatically shut itself down, drain the fuel from the primary loop and passively handle the decay heat,” says Bob Hargraves, a Dartmouth physics professor who has joined Thorcon’s team. “The cooling water circulates by natural induction and gravity. There are no electric pumps involved. This means there’s no need for operator intervention. In fact there is nothing the operators can do to prevent the draining and cooling. ThorCon is walkaway safe,” meaning the operators can simply walk away from the reactor in case of a malfunction. The reactor takes care of itself.
ThorCon is designed to sit 30 meters underground for additional safety. It has four gas tight barriers, all about 15-30 meters below grade, separating the reactor from the atmosphere. ThorCon operates at near-ambient pressure so that in the event of a primary loop rupture, there is little energy to disperse radioactive materials. “The spilled fuel merely flows into the drain tank where it is cooled,” says Hargraves. “The most troublesome fission products, including strontium-90 and cesium-137, are chemically bound to the salt. They end up in the drain tank as well.”
All this sounds like a pretty good new approach to nuclear power, doesn’t it? So is there any chance of building ThorCon’s first model that it says can be ready in four years? Well, unfortunately, no.
The NRC now charges applicant $279 an hour to undertake the review process, which can take up to five years. The Commission only gets about 15 percent of its funding anymore from Congress. It raises the remainder from fees charged ro its applicants. The GAO recently estimated it takes $1-2 billion to get through the entire design approval process – an amount that is way beyond ThorCon’s capabilities. “They’re just doing what Congress tells them to do,” says Hargraves.
“So we’ve gone to other countries. We’re looking at Canada, Australia, and the Southeast Asia area – anywhere where they need nuclear and are interested in new nuclear.” ThorCon has just filed its recommendations with the Australian Nuclear Fuel Cycle Royal Commission, which is now considering nuclear power for Australia.
Unfortunately, the Nuclear Regulatory Commission does very little these days except listen to the complaints of anti-nuclear activists and impose further safety restrictions on existing reactors. The NRC did approve the construction of two new reactors in Georgia and South Carolina since the beginning of the Obama Administration. But its main accomplishment occurred when former Senate Majority Leader Harry Reid refused to advance any new legislation until Bush accepted Gregory Jaczko, a physicist on Reid’s staff, as an appointee to the five-member commission. President Obama then appointed Jaczko as chairman in 2009. Using his new authority, Jaczko immediately set about closing down the Yucca Mountain high-level waste repository, withholding information from the other four commissioners in the process. The move squandered $10 billion and set the effort to deal with the nation’s spent fuel back ten years. Jaczko then left the NRC and went on a speaking tour of the country urging that New York’s Indian Point and other major reactors be shut down.
In this kind of environment, there is very little chance that any new nuclear design of technology will see the light of day. Bill Gates learned this when his company, Intellectual Ventures, put a proposal before the NRC for his Travelling Wave, a reactor that consumes its own waste and doesn’t have to be refueled for 50 years. Gates soon saw the writing on the wall and went to China instead to develop the new technology.
“The Chinese are moving ahead in all directions,” says Hargraves. “They’re experimenting with thorium, the fast breeder, SMRs – everything. They’re even going to American scientists at Berkeley and other places for advice.” And so the products of fifty years of American research are slowly but surely being transferred to the more adventurous Chinese. In another 15 years we’ll probably be buying our nuclear reactors from them.