America's fusion future
Posted: Wednesday, April 02, 2008 7:25 PM by Alan Boyle
Sean Ahern / ORNL |
This visualization shows how the plasma within the ITER reactor would be heated
by radio frequency waves. Click here to watch a video of the simulation.
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The long-term future of energy may well lie in clean, plentiful fusion power - but will the reactors that produce that power carry a "Made in the USA" label? That's a big issue on the agenda for the U.S. ITER program, which is cooperating with six international partners to build the first power-generating fusion prototype in France by 2016.
The year 2016 may sound like a long time from now, but the "Made in the USA" issue isn’t something that can be put off for eight years. It needs to be addressed right now - and that's a big problem for Ned Sauthoff, the head of the U.S. ITER Project Office at Oak Ridge National Laboratory.
Here's why the next few months are important: The design for the eight-story-high plasma containment vessel has been in the works for years. After dealing with some last-minute uh-ohs, such as a nasty potential problem with burping plasma, the seven parties in the $13 billion ITER project have finally addressed "most, if not all, of the major construction issues," Sauthoff told me last week during my visit to his headquarters in Tennessee.
Sauthoff said the design outline is expected to become frozen in place around June, when representatives of the project's seven parties (the United States, China, Europe, India, Japan, Russia and South Korea) meet in Japan.
"The schedule would say it has to be frozen this summer," he said. Then the specs would be reviewed by the parties and sent out to contractors by the end of the year. (ITER used to stand for International Thermonuclear Experimental Reactor, but nowadays the effort's publicity material downplays the acronym and plays up the idea that it's a Latin word for "the way." The June meeting is the next milestone along the way.)
Each of the parties behind ITER has been given responsibility for jobs that add up to a percentage of the total project. For the United States, that amounts to 9.1 percent - taking in parts of the doughnut-shaped reactor vessel as well as vacuum pumps and some of the plumbing, superconducting cables and more. Different nations will provide some of the same components for the reactor.
That piecemeal approach is deliberate, Sauthoff said. "ITER is not in itself designed to do things in the most cost-effective way," he admitted. Rather, it's designed to give all the partners a piece of the technological action.
"Everybody wants to make their own ITER at the end of the day," Sauthoff explained.
Fusion and financial frustrations
This is where Sauthoff is facing a dilemma: He and his colleagues at U.S. ITER are responsible for providing the components they've promised, whether they're built in the United States or elsewhere.
"Our desire is to spend the U.S. money, as much as possible, in the U.S.," Sauthoff said. But different countries have different ways of making things.
For instance, consider one of the high-tech blanket shield modules for the reactor vessel. Making that module is much like making an engine for an automobile, Sauthoff said. There are several ways to do it - casting the module from alloy, forging a block and then drilling it out, or even creating it from metal powder using a technology called hot isostatic processing.
ORNL |
Ned Sauthoff heads
the U.S. ITER project.
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Automakers might well be in a good position to make those modules, but would they be U.S., Japanese or American automakers? If the components can't be made in America to fit the international specifications, they'd have to be made somewhere else - with the American taxpayer footing the bill.
Sauthoff had been planning to work with potential U.S. manufacturers this year to make sure they could meet the specs. Then, in a surprise move, Congress axed virtually all the money that was set aside for ITER operations during the current fiscal year. That left the manufacturers in the dark.
"We were expecting to do $50 [million] to $100 million worth of industrial presentations. ... That's the major consequence of our little bump in the road," Sauthoff said.
U.S. ITER's industrial efforts haven't completely come to a standstill. "I had a little bit of a war chest put away," Sauthoff said. But he's really hoping for some of the money to be restored in a supplemental appropriation, which may be attached to a war-funding measure expected to come up in Congress sometime in the next couple of months. And he's absolutely counting on Congress to come through with the money sought for the next fiscal year.
He isn't the only one in wait-and-see mode. So far, the other ITER parties have been sympathetic to Sauthoff's political plight, but he said "their patience will not extend into '09."
Is this trip necessary?
Is commercial fusion power worth getting impatient about? After all, there are lots of other energy sources out there, ranging from biofuels and cleaner coal to resurgent nuclear fission power and renewable solar and wind power.
ITER / ORNL |
This artist's conception shows a cutaway of the ITER
plasma containment vessel. A human figure is
included at lower right to provide a sense of scale.
Click on the image for a larger version.
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Sauthoff agrees that fusion won't be the magic solution to the energy problems, even in the year 2050. "This problem is bigger than what any single technology will solve," he said.
However, if ITER and its successors work the way engineers think they will, fusion could fit a big niche now occupied by oil-fired, gas-fired, coal-fired and nuclear power plants - the very niche that will need something totally new in the next few decades.
At the currently projected rate of growth in energy consumption, the world will be using 50 to 100 times as much energy in the 2050-2100 time frame. "In roughly 50 years, we better change a large part of the way we produce energy, particularly if the developing world is going to be striving to get the energy consumption of the developed world," Sauthoff said.
If the fusion reaction can be perfected by that time, the technology would offer a huge advantage: The fuel for fusion - isotopes of hydrogen that are combined to produce helium plus surplus energy - can be isolated from sea water. And it doesn't take much of that fuel.
In order to generate 1,000 megawatts of electricity in a day, you could burn 9,000 tons of coal, liberating 30,000 tons of carbon dioxide in the process. Or you could take a few pounds of deuterium and tritium, and turn that into a slightly smaller amount of helium - without producing any greenhouse gases.
Forever in the future?
When you get right down to it, even oil and gas, wind and solar power can be traced back to the closest working fusion reactor we know: the sun. Scientists have been working for decades to capture that solar-style power plant in a magnetic bottle.
Sauthoff has heard the old joke: "Fusion is the energy source of the future, and always will be." He admits that 20 years ago, his predecessors were saying commercial fusion power was just 20 years away. But the way he sees it, those estimates were stated in the wrong way.
"We measure progress by dollars," he said. Thus, the old estimates should have been cast as projecting commercial fusion power after 20 years, based on annual funding of $2 billion, he said. Today, Sauthoff estimates that commercial fusion is about 35 years away, based on the current funding plan.
The U.S. Department of Energy's plan calls for spending $214.5 million on ITER in the coming fiscal year, with the total U.S. project cost for the construction phase amounting to between $1.45 billion and $2.2 billion by 2015. (Remember, that figure should represent 9.1 percent of the full ITER cost.)
The U.S. share of operating costs would amount to about $80 million a year between 2015 and 2034, according to the Energy Department's plan, and decommissioning ITER would cost the federal government $1.25 billion.
Can scientists and engineers actually figure out how to create a controlled fusion reaction with a net energy gain? So far, we've just been talking about the ITER approach to the fusion puzzle - but the government is funding two other approaches as well:
- One of those efforts, headquartered at Lawrence Livermore National Laboratory in California, involves blasting away at pebbles of deuterium and tritium with dozens of laser beams. The National Ignition Facility is due for completion in 2009 or 2010, with a total price tag that some have estimated at $5 billion or more.
- The other effort has gotten only a pittance of funding from the federal government, but a lot of buzz from the Internet. Researchers in New Mexico are seeking to duplicate the late physicist Robert Bussard's experiments with an electrostatic plasma containment device that appeared to offer a low-cost route to fusion. Today, team leader Richard Nebel told me that the device was still under construction, and that testing had not yet begun. "We're getting close," he said.
Sauthoff said he welcomed those alternative efforts to solve the puzzle.
"First you do the physics," he said. "You get yourself a burning plasma. Once you've gotten a burning plasma, then it's a matter for the politicians to decide, do they want to invest in the technology? ... Let's just play by the same rules."
Do those sound like rules to live by? Feel free to weigh in on the promise and the puffery surrounding fusion research by leaving your comments below.
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