The future of clean energy creation is not with massive banks of solar panels that only work (a) during the daytime (b) when there is no dust or snow on them, or giant windmills that work when the wind blows. It will come with nuclear energy and eventually with fusion energy.

Two and a half years ago, MIT entered into a research agreement with startup company Commonwealth Fusion Systems to develop a next-generation fusion research experiment, called SPARC, as a precursor to a practical, emissions-free power plant.

Now, after many months of intensive research and engineering work, the researchers charged with defining and refining the physics behind the ambitious reactor design have published a series of papers summarizing the progress they have made and outlining the key research questions SPARC will enable.

SPARC is planned to be the first experimental device ever to achieve a “burning plasma” — that is, a self-sustaining fusion reaction in which different isotopes of the element hydrogen fuse together to form helium, without the need for any further input of energy. Studying the behavior of this burning plasma — something never before seen on Earth in a controlled fashion — is seen as crucial information for developing the next step, a working prototype of a practical, power-generating power plant.

The high power in a small size is made possible by advances in superconducting magnets that allow for a much stronger magnetic field to confine the hot plasma.

The analysis done so far shows that the planned fusion energy output of the SPARC reactor should be able to meet the design specifications with a comfortable margin to spare. It is designed to achieve a Q factor — a key parameter denoting the efficiency of a fusion plasma — of at least 2, essentially meaning that twice as much fusion energy is produced as the amount of energy pumped in to generate the reaction. That would be the first time a fusion plasma of any kind has produced more energy than it consumed.

The calculations at this point show that SPARC could actually achieve a Q ratio of 10 or more, according to the new papers. While Greenwald cautions that the team wants to be careful not to overpromise, and much work remains, the results so far indicate that the project will at least achieve its goals, and specifically will meet its key objective of producing a burning plasma, wherein the self-heating dominates the energy balance.

Greenwald says there is still much to be learned about the physics of burning plasmas, and once this machine is up and running, key information can be gained that will help pave the way to commercial, power-producing fusion devices, whose fuel — the hydrogen isotopes deuterium and tritium — can be made available in virtually limitless supplies.

The details of the burning plasma “are really novel and important,” he says. “The big mountain we have to get over is to understand this self-heated state of a plasma.”



  1. I think most of us have always thought self-sustaining fusion reactors would happen, it’s just that after being told, “it’s 20 years away” for 50 years, the optimism dims. They didn’t know how tough the problems really were.

    The equations for fluid flow are unsolvable in principle; if I recall correctly it’s 18 equations in 21 unknowns. In this case, the fluid is plasma so they need to add electromagnetism to the mix.

    I sincerely hope they’re close enough to get there in a few years, I’m just not taking odds. I’m really interested in how the million (billion?) dollar reactors hold up to the neutron flux and the things they don’t know that they don’t know, once reactors start working. Neutron embrittlement is a thing and they’re not going to divert the neutrons with fancy electromagnets. What other things that can degrade the reactor are there?

    Considering how the greenies reject fission power, which is about as safe and clean as one can get, it reinforces the idea that they just want to get rid of humanity. We’ve known how to safely handle the nuclear waste for decades, and you still hear “but what about the radioactive waste!?!” “Environmentalism” is just about keeping their favorite places prettier. Preserving “untouched wilderness.”

    • I put the article up on the blog hoping to get comments like this. BECAUSE as you point out and as the last sentence says, “The big mountain we have to get over is to understand this self-heated state of a plasma.” I agree that we’re a long way from getting working fusion reactors to power the grid, but the research is important. The French are chewing hard on the problem and are ahead of the game, but it’s difficult to know what “ahead” really means.

      I’m surprised that President Trump isn’t promoting safe nuclear power but the polling may not support it, politics being what it is. The left has blaggarded nuclear power for so long with their media shills that it is rejected by the public.

  2. Where’s Tony Stark and his ARC Reactor when you need him? But seriously, this is encouraging and hopefully not too far off in implementation. In the meantime nuclear is still the best solution, not yens of thousands of rural land and viewsheds covered with monster wind turbines or solar panels (plus the “no storage” aspect). The other day came across a push-marketing report from some group of academic “scientists” stating wind and solar are now more efficient and cheaper than nuclear. Wonder who funded that one? Oh wait, the “alternative sustainable clean green energy” industry. Typical lie from the Left.

    Great summation LL.

        • Yes, those obnoxious windmills are an eyesore; an eyesore that is visible for 35 miles away. Hundreds of years from now, these monstrosities will be only a memory of the foolish attempts by humans to advance. These things are not advancing anything except windmill salesman’s commission checks.

          We won’t even discuss their efficacy when the wind dies down. Nor the complete lack of storage to harness any of the meager power gained for future use. These things are about as hare brained as anything else I can think of.

        • As do cattle, horses, elk and deer, and people who are forced to live next to them. And they are getting taller, 675′ (off shore towers used for on shore).

          A full-on gambit for when they sell the field assets…big money subsidized by taxpayers. Good work if you can get it…but that pesky “selling of ones soul” comes to mind. They will be held accountable for be bad neighbors.

        • Those cursed abominations are ruining the west- every grand view of Gods creation is now covered with the damned things. Pimples on the earth.
          And we pay for them, because they can’t pay for themselves.
          And try getting rid of them- harder than to build them, if a utter mess is not to remain behind. Like a crappy old fiberglass boat- they don’t rot, you can’t burn them, they are too big for a landfill, they just sit and molder basically forever.

          • Ditto.

            Their envrio-senstitive (not!) approach is to bury them on site, carbon-fiber has a 500 year half-life. But…but…it’s “green” energy. Uh huh, sure…and I have some Florida swampland for sale.

            I like SMR’s, which LL has outlined here before. A good stop-gap approach until SPARC comes on line.

          • 2000 years from now, archeologists will find hundreds of thousands of the windmill abominations in land fills and will wonder how we could be so stupid.

          • Two thousand years from now archeologists [1] will puzzle over the wind turbines and conclude that they were “religious artifacts”. And they will be correct.

            [1] Actually there will be no archeologists because the Earth will resemble Venus, a hellish hothouse due to anthropogenic climate change.
            [1a] There will be no archeologists, only deracinated savage cannibals barely capable of speech, clad in stinking, untanned hides, wandering the surface of the Earth.
            [1b] Future archeologists will label the windmills as “sex toys (probable)” and leave it at that, since all will understand the contextual shorthand for “don’t know and don’t care”.

          • Religious artifacts, indeed.

            So Earth may become Dune? Common earth worms will become sand worms?

            Life imitates art?

  3. Beyond a doubt actors and musicians as well as other experts will be against it because of SCIENCE! I live downwind from a nuke and I’m not in the least concerned.

  4. It seems that France gets most electricity from nuclear power with safety.

    I don’t understand the physics involved, don’t have that kind of mind, but am all for anything that gets rid of the damn windmills. A blight to the eyes and requires enormous landfills when they fail/wear out.
    Soon, when President Trump is reelected and Harry Reid’s blackmailer material is outdated, the nuclear waste storage can proceed.

    • I think that we will have a space elevator (that will take you into orbit) at about the same time as fusion energy becomes a reality.

      I’m not a space elevator denier, LSP. It simply takes a lot of money and a lot of science to get an elevator from the equator here on Earth to orbit.

  5. I’m with SiGraybeard on this. When I was working at Fermilab in the 1970’s the “Tokamak” was The Next Great Thing, and we’d have fusion power too cheap to meter within 5 years.

    Too many “Unknown Unknowns” at this point in time.

    • Yes, but you slog forward and keep working on the peripherals like superconducting magnets to contain the plasma, or whatever and see where it goes. The fact that we don’t know much about how superheated plasma will behave means that at some point, it’s likely to break containment and you don’t want to be on your coffee break 100′ away when that happens.

      • I agree. Always keep moving forward, finding the unknowns, and either solving the problems they cause, or coming up with a work-around until we can solve it.

        The early superconducting magnets we had were fraught with problems. When they “went normal”, i.e., dropped out of superconducting mode for some reason, they had a very disturbing habit of pretty much turning themselves inside-out. It caused a lot of collateral damage when that happened….

  6. Fusion would be nice. We’ll see.

    I don’t find the windmills ugly or annoying, but they’re certainly a boondoggle.
    PV farms are way uglier IMO, and also a boondoggle.


  7. While all of that is nice, why are we not building new latest generation pebble bed or other self damping design nuclear plants? The tech is proven, stable and if the politicians get their thumbs out of their arses, Yucca mountain could be operational and storing the byproducts of the systems safely. Clean energy today for a fraction of the cost of most other systems. When fusion becomes reality, just phase older tech out.

    Keep an eye on CA, they are in for a very big shock (no pun intended) when they find that EV’s are not the answer to the economy with a failing electrical grid and no new generating capacity. I may live long enough to have a laugh at that. Then again, maybe CA can turn conservative (nah! That won’t happen in my lifetime).

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