Questions and answers with Stephen Dean and Daniel Clery
Two recently published books describe the history of nuclear fusion research. Search for the Ultimate Energy Source: A history of the US Fusion Energy Program (Springer, 2013) is written by Stephen Dean, president of Fusion Power Associates, a nonprofit advocacy organization. Dean is also a former administrator of the US Department of Energy’s fusion research program. Science magazine deputy news editor Daniel Clery’s A Piece of the Sun: The Quest for Fusion Energy (Overlook Press, 2013), provides a more global perspective on the same subject. Physics Today reviewed both books together in March and recently caught up with the authors to discuss their respective works.
Daniel Clery (left) and Stephen Dean.
PT: Many books have been written about fusion. What made you decide to write yours, and what does it offer readers that others don’t?
Dean: Most of the books you’ve seen on fusion are general books about the science, technology, and the engineering of the program. The last book that dealt with fusion history at all was back in 1982 by Joan Bromberg [Fusion, Science, Politics and the Invention of a New Energy Source, MIT Press]. So I thought I would like to bring all of that up to date. Also I wanted to bring a slant, based on my own personal experiences in observation and management of the program over 50 years, that had to do with the politics. I don’t think there’s been a book that has dealt with all of that as comprehensively as I thought I could bring to bear.
Clery: I wanted to write a book that was really accessible to the general public, those who didn’t have any background in fusion. It’s such an important topic and not enough people seem to know about it. I also wanted to tell the story of the people involved in fusion. Rather than being a book about the science, I aimed to describe the development of fusion, mixing together the politics and history over the past 60 years. It’s just a fascinating story that hasn’t adequately been told.
PT: Describe the audience you expect for your book. Researchers? Students? The general public?
Dean: My hope was it would be useful to students getting interested in the field to see what the nature of the program is, how long it’s going to take, what the options are, and what the excitement and ultimate promise is. Springer priced the book so high that I don’t think too many students will be able to afford it out of their own pockets. But I think Springer is going to get it in to all their libraries. I hope it will also be useful to researchers in political science and the history of science—what are the politics and issues associated with big science, especially in the US.
Clery: I hope that scientists would enjoy it. It won’t teach them a lot other than the history of their subject. I also hope that students of fusion will be enthused by reading it and seeing the work that has gone before. But I think anyone that’s interested in where our future energy is going to come from and concerned about the future of the planet will benefit from reading it.
PT: Which approach—magnetic confinement with tokamak reactors or inertial confinement—do you think will win out to become the future energy source?
Dean: I think it’s too early to narrow down to one. It’s clear that tokamak is way out in front. It’s been demonstrated to work scientifically. The problem with tokamaks is they are big, expensive and complicated. It would be nice to find something more simpler, less expensive and a little bit smaller. I still hope that inertial fusion will come through, but until the National Ignition Facility at the Lawrence Livermore National Laboratory in California, or someone else ignites a fusion pellet, you can’t really put inertial on the same platform of promise that the tokamak is currently on. Until NIF shows that you can ignite a pellet and what kind of techniques are going to be required, it’s not obvious how to extrapolate from current data.
Clery: Some proponents of inertial fusion give very optimistic forecasts. But the fact that to be economic it’s going to have to produce gainful explosions many times a second when currently they carry out about one per day, without gain, means that inertial fusion is far harder, it seems to me, than a steady-state magnetic machine. I would have to put my money on magnetic fusion at the moment.
PT: As you know, the US government is questioning its commitment to ITER (the international fusion project in Cadarache, France); is it alone among the ITER parties to do so?
Dean: You do not get much reliable information on that because the governments aren’t very open. In fact, our government is not very open about what they are doing about ITER either. The US’s commitment has not been that strong, at least in terms of paying for it and keeping it on schedule. So far I think the US will hang in there. If the schedule slips, the fact the US is not coming up with the money to keep it on schedule may not be a show stopper; the money that the US is willing to put into ITER year to year may be adequate. We won’t be able to judge that today. As far as I know, all the other countries have measured up to their commitments so far. [ITER has] run into difficult issues because of its scale and complexity. I expect that its schedule will slip. I have no doubt of it. Everybody thinks it will slip two or three years [beyond its official 2020 completion date] and that will lighten up the financial problem for everybody in the near term.
Clery: The US situation is very tricky because Congress has restricted the fusion budget to such a low level. So continued participation in ITER means really hard decisions for the domestic program. Unsurprisingly, US scientists are questioning whether sticking with ITER is worth their while because it’s getting to the stage where they can do virtually nothing at home. In my opinion, if the US government is serious about fusion it needs to spend more so it can participate in ITER and have an effective domestic program.
PT: The cliché is that large-scale controlled fusion is 30 years away and always will be. Do you think there is much hope of fusion ever becoming a viable energy source, perhaps in our children’s lifetime?
Dean: I used to think it would become a viable energy source in my lifetime. But I’ve become somewhat of a skeptic on how soon it will come to fruition. It has turned out to be extremely difficult. Funding has played a role, politics has played a role, and management has also played a role in not getting it done by now. I don’t know if it will be in our children’s lifetime; maybe our grandchildren. I hope it will come to pass in our children’s lifetime, at least in Asia and Europe. I’m not sure about the US. When the technical job is done and it’s ready to move into power plants, I think there’s going to be an issue about whether it can compete economically, especially in the US, where economics drives everything. In some other countries, national decisions can override things like that, and it could be that we could get fusion electric power in some Asian countries independent of whether there are power sources that are cheaper, especially if there’s antinuclear sentiments, environmental regulations, and sentiments against fossil fuels.
Clery: I’m not a fusion scientist. I think ITER will work and it will produce more energy than it consumes. They’d be really unlucky if it didn’t. But a power utility is never going to want something like ITER because it’s so complicated. Researchers will have to simplify tokamaks and also prove that you can run one for 30 years with little maintenance. No one ever said it was going to be easy, but there is so much to gain from the effort. If you can get it to work economically it will change the world, so it’s worth persisting with it.