MIT changes the world of nuclear fusion
- October 20, 2016
- 1062 views
While it may not be a record tracked by Guinness, it was a moment heard all around the nuclear industry (though more softly in the rest of the world).
Recently, MIT set a new world record for plasma pressure in the Institute’s Alcator C-Mod tokamak nuclear fusion reactor (part of the work at MIT's Plasma Science and Fusion Center).
What's so darn important about plasma pressure? That's where the energy production comes from in a nuclear fusion reaction. And just to be completely clear, current power production uses fission, not fusion. Fission splits, fusion combines. Fusion has greater production potential than fission, but it's been harder to control--hence why we've relied on fission so far. But, scientists are working on making fusion--which powers the sun--a better option. And MIT is that work in action (or was, read on for more info there).
Why should we really care whether those atoms are being split or fused? Ah, here's the real fun part: Fission is more stable, but creates that unhappy nuclear waste we have to deal with (fundamentally forever). Fusion does not: no waste. And, another bonus: no chance of a meltdown.
MIT's Alcator C-Mod tokamak reactor, which has been hard at work at MIT for over 20 years in this bid to make fusion a real part of the energy game, has been making slow and steady advances in plasma pressure for quite awhile now. In fact, MIT broke its own record for plasma pressure, in all honesty. The previous record was 1.77 atmospheres set in 2005. This most recent one hit 2.05 atmospheres, a 15 percent improvement. (And they got the interior of the reactor twice as hot as the center of the sun, which is cool---in a social, not physical way---in and of itself.)
The Guardian called MIT's record breaking advance "another step on the long road towards the unlocking of limitless clean energy" this week.
"Fusion holds the promise of an inexhaustible, clean and safe source of energy – one of the dreams of humankind," began the opening statement of Director General Yukiya Amano at the 26th International Atomic Energy Agency Fusion Energy Conference this week in Japan (where MIT's record was officially announced). "To make fusion energy production a reality, enormous scientific and technical challenges still need to be overcome. But I have faith in the ingenuity of human beings and the ability of brilliant scientists and engineers to overcome even the most daunting technological hurdles. In the coming years, we will see increased efforts to bring fusion energy on an industrial, power-plant scale within our reach. I am confident that they will be successful."
Sadly, though, the funding for the C-Mod ended just as the record was hit. While work on fusion will continue, money and focus will likely shift to the ITER machine in France. (There is a growing gap between the nuclear arm that sees fission working better bigger, as with ITER, and those who see it working better smaller, as with the reactor at MIT. Obviously, so far, the bigger camp is winning. ITER has massive international support. And the funding being pulled from MIT by the DOE for the C-Mod is, in fact, going to ITER.)
“This result confirms that the high pressures required for a burning plasma can be best achieved with high-magnetic-field tokamaks such as Alcator C-Mod,” says Riccardo Betti, the Robert L. McCrory Professor of Mechanical Engineering and Physics and Astronomy at the University of Rochester and quoted in MIT News when the results were announced in early Oct.
"As innovations [like the record-breaking one at MIT] are more understood, I can see how that might change the picture for some people and make people more comfortable with nuclear reactors," MIT president's L. Rafael Reif said on CBS This Morning Oct. 20, where he discussed the nuclear record, the utility's push to create a meltdown-proof nuclear reactor (which was cited separately but is, as discussed earlier here, part of the same kit and kaboodle with fusion) and other research going on at MIT as well.
Lead photo by Bob Mumgaard/Plasma Science and Fusion Center.