How realistic is this practical fusion timeline

Nom_de_Plume · March 2, 2015, 8:21pm

According to an article in Forbes, Skunk Works, the experimental technology branch Lockheed Martin, has announced plans to build a practical fusion reactor that could be as small as a jet engine.

According to that article, and a few more I’ve seen, they hope to have an operational unit by 2017, and to be mass-producing them within a decade.

So, any chance that this design would work, and, if so, does the timeline sound realistic?

XT · March 2, 2015, 8:40pm

Assuming they have actually made a breakthrough in the magnetic bottle containment system and can release the heat in a controlled manner (to run a turbine) then I guess they could have a working unit by 2017…and, at least theoretically, go into production after they have proved the concept.

As the article says, if they have managed to do this it’s a pretty big achievement and it certainly could have far reaching implications if they can pull it off. The fact that Lockheed Martin is releasing this info kind of tells me that they at least THINK they can do this, as we aren’t talking about a fly by night company trying to get some backers here, but a major aero-space company with a lot of reputation to lose if they don’t have anything by vaporware on this.

Grey · March 2, 2015, 8:57pm

Until there’s some actual data provided I’m not holding my breath.

XT · March 2, 2015, 9:03pm

I’m much more optimistic and even I don’t plan to hold my breath for 2 more years. :eek:

davidm · March 2, 2015, 9:06pm

Actuallly, it does sound like they are trying to get backers.
From the OP’s link:

I have to wonder why they’re looking outside Lockheed for support.

Amateur_Barbarian · March 2, 2015, 9:10pm

My understanding is that no one has created a sustained fusion reaction on any scale, under any circumstances. (That God guy excepted, I guess.) The leap from a sustained fusion reaction in any form to one that’s packaged and ready to go is almost as big as the leap to that sustained reaction from… now.

I understand they’ll have an antigravity car in the same time frame. Just a few more kinks in that AG drive to iron out.

XT · March 2, 2015, 9:12pm

They aren’t looking for backers to develop it, they are looking for partners once it’s developed to go into production. Why? They probably don’t have the capacity to go into large scale production and distribution (as well as marketing and all the rest) on their own.

Sure, this could be vaporware hype, but the fact that LM is making the claim and setting a hard date makes me at least consider that it could be real. Guess we shall see…2 years is a pretty short time line, so either they are VERY confident that they pretty much have all of the major technical challenges solved and it’s just engineering at this point, or they were VERY foolish to release this to the public.

XT · March 2, 2015, 9:17pm

Do you seriously put an anti-gravity device, something we don’t even have a theory on, in the same league as a fusion power plant, something we have been literally working of for decades???

Amateur_Barbarian · March 2, 2015, 9:24pm

If they’re talking about selling them in a crate at Home Depot in two years, yes. May as well make them capable of time-travel as well.

That fusion is real - in stars and thermonuclear detonations - and anti-gravity and time travel are “fictional” is of little difference in this case. They are talking about sustainable packaged versions of something that has barely been achieved on a mega-laboratory scale, and only for short periods.

davidm · March 2, 2015, 9:25pm

Here’s a page about it from Lockheed Martin’s website, rather than a second hand account from some Forbes reporter. The emphasis seems to be on reducing the size rather than on currently having a working design for a net energy gain reactor. As I understand it, they’re saying that the reduced size will speed up the development and testing cycles which, they claim, will enable them to produce a practical reactor within 5 years, So the “practical reactor within a few years” claim seems to be a prediction based on this sped up cycle rather than an announcement of some fundamental breakthrough in containment.

XT · March 2, 2015, 9:34pm

Except no where that I see are they saying that…that’s YOUR spin.

There are a lot of things that were studied for years, even decades when breakthroughs occurred that enabled someone to go from theoretical to practical to production. I don’t know whether this is one of those cases, but it’s kind of ridiculous of you to equate this to anti-gravity, which we don’t even have something like a working theory on how to produce even in a lab, or time travel, which is theoretically possible but which we don’t have any idea how to create, if it’s even possible, and based on your own spin about these things being in Home Depot next year.

Amateur_Barbarian · March 2, 2015, 9:34pm

So they don’t have a working fusion reactor yet - duh - but they’re going to make it smaller to make it work better.

Uhhhhh-huh.

And they want a manufacturer standing by to start bashing them out when it’s ready in 2 years.

Uhhhhhhhhhhh-huh.

XT · March 2, 2015, 9:38pm

One of the links on that page goes to an article here:

Although the company released limited information on the CFR in 2013, Lockheed is now providing new details of its invention. Aviation Week was given exclusive access to view the Skunk Works experiment, dubbed “T4,” first hand. Led by Thomas McGuire, an aeronautical engineer in the Skunk Work’s aptly named Revolutionary Technology Programs unit, the current experiments are focused on a containment vessel roughly the size of a business-jet engine. Connected to sensors, injectors, a turbopump to generate an internal vacuum and a huge array of batteries, the stainless steel container seems an unlikely first step toward solving a conundrum that has defeated generations of nuclear physicists—namely finding an effective way to control the fusion reaction.

“I studied this in graduate school where, under a NASA study, I was charged with how we could get to Mars quickly,” says McGuire, who earned his Ph.D. at the Massachusetts Institute of Technology. Scanning the literature for fusion-based space propulsion concepts proved disappointing. “That started me on the road and [in the early 2000s], I started looking at all the ideas that had been published. I basically took those ideas and melded them into something new by taking the problems in one and trying to replace them with the benefits of others. So we have evolved it here at Lockheed into something totally new, and that’s what we are testing,” he adds.

To understand the breakthroughs of the Lockheed concept, it is useful to know how fusion works and how methods for controlling the reaction have a fundamental impact on both the amount of energy produced and the scale of the reactor. Fusion fuel, made up of hydrogen isotopes deuterium and tritium, starts as a gas injected into an evacuated containment vessel. Energy is added, usually by radio-frequency heating, and the gas breaks into ions and electrons, forming plasma.

The superhot plasma is controlled by strong magnetic fields that prevent it from touching the sides of the vessel and, if the confinement is sufficiently constrained, the ions overcome their mutual repulsion, collide and fuse. The process creates helium-4, freeing neutrons that carry the released energy kinetically through the confining magnetic fields. These neutrons heat the reactor wall which, through conventional heat exchangers, can then be used to drive turbine generators.

Until now, the majority of fusion reactor systems have used a plasma control device called a tokamak, invented in the 1950s by physicists in the Soviet Union. The tokamak uses a magnetic field to hold the plasma in the shape of a torus, or ring, and maintains the reaction by inducing a current inside the plasma itself with a second set of electromagnets. The challenge with this approach is that the resulting energy generated is almost the same as the amount required to maintain the self-sustaining fusion reaction.

Neutrons released from plasma (colored purple) will transfer heat through reactor walls to power turbines. Credit: Lockheed Martin
An advanced fusion reactor version, the International Thermonuclear Experimental Reactor (ITER), being built in Cadarache, France, is expected to generate 500 MW. However, plasma is not due to be generated until the late 2020s, and derivatives are not likely to be producing significant power until at least the 2040s.

The problem with tokamaks is that “they can only hold so much plasma, and we call that the beta limit,” McGuire says. Measured as the ratio of plasma pressure to the magnetic pressure, the beta limit of the average tokamak is low, or about “5% or so of the confining pressure,” he says. Comparing the torus to a bicycle tire, McGuire adds, “if they put too much in, eventually their confining tire will fail and burst—so to operate safely, they don’t go too close to that.” Aside from this inefficiency, the physics of the tokamak dictate huge dimensions and massive cost. The ITER, for example, will cost an estimated $50 billion and when complete will measure around 100 ft. high and weigh 23,000 tons.

The CFR will avoid these issues by tackling plasma confinement in a radically different way. Instead of constraining the plasma within tubular rings, a series of superconducting coils will generate a new magnetic-field geometry in which the plasma is held within the broader confines of the entire reaction chamber. Superconducting magnets within the coils will generate a magnetic field around the outer border of the chamber. “So for us, instead of a bike tire expanding into air, we have something more like a tube that expands into an ever-stronger wall,” McGuire says. The system is therefore regulated by a self-tuning feedback mechanism, whereby the farther out the plasma goes, the stronger the magnetic field pushes back to contain it. The CFR is expected to have a beta limit ratio of one. “We should be able to go to 100% or beyond,” he adds.

This crucial difference means that for the same size, the CFR generates more power than a tokamak by a factor of 10. This in turn means, for the same power output, the CFR can be 10 times smaller. The change in scale is a game-changer in terms of producibility and cost, explains McGuire. “It’s one of the reasons we think it is feasible for development and future economics,” he says. “Ten times smaller is the key. But on the physics side, it still has to work, and one of the reasons we think our physics will work is that we’ve been able to make an inherently stable configuration.” One of the main reasons for this stability is the positioning of the superconductor coils and shape of the magnetic field lines. “In our case, it is always in balance. So if you have less pressure, the plasma will be smaller and will always sit in this magnetic well,” he notes.

Overall, McGuire says the Lockheed design “takes the good parts of a lot of designs.” It includes the high-beta configuration, the use of magnetic field lines arranged into linear ring “cusps” to confine the plasma and “the engineering simplicity of an axisymmetric mirror,” he says. The “axisymmetric mirror” is created by positioning zones of high magnetic field near each end of the vessel so that they reflect a significant fraction of plasma particles escaping along the axis of the CFR. “We also have a recirculation that is very similar to a Polywell concept,” he adds, referring to another promising avenue of fusion power research. A Polywell fusion reactor uses electromagnets to generate a magnetic field that traps electrons, creating a negative voltage, which then attracts positive ions. The resulting acceleration of the ions toward the negative center results in a collision and fusion.

XT · March 2, 2015, 9:40pm

That’s not even what the Forbes article said. Good grief, why did you even post in this thread if you weren’t going to bother even reading the fluff article??

Amateur_Barbarian · March 2, 2015, 9:50pm

The OP’s summary seems quite clear. And represents absolute balderdash. What more needs be said?

XT · March 2, 2015, 9:51pm

You are right, nothing more to see here…go ahead and move along.

davidm · March 2, 2015, 9:55pm

To be fair, that’s not what they’re saying, at least if I’m understanding it right. What they’re saying is that, by making it smaller, they can build prototypes quicker, thus speeding up the process of repeated prototyping and testing. The hope is that this will lead more quickly to a solution to the containment problem.

DinoR · March 2, 2015, 10:17pm

A good GQ thread from closer to the announcement.

Maybe they really are close to a leap that seems unlikely to those that know the state of the science minus some unshared still proprietary knowledge. I liked one of the comments on the Forbes article “In 2 years, Mr. McGuire will either have a Nobel Prize or be totally unemployable.”

Amateur_Barbarian · March 2, 2015, 10:22pm

That’s all fine, but this has been lather-rinse-repeat for nearly 60 years with very little fundamental movement forward. Any article that’s jumping ahead to producible units and so forth is well into moonbeam land.

Build a sustainable fusion reactor of any kind, then build one that can generate power sustainably using any model and combination of technologies, and then start musing about optimizing it for a small, manufacturable package. Otherwise it’s like those fan efforts to design the last detail of a real starship… except, you know, for that engine thingy.

I believe fusion power is humanity’s only good option for long-term survival. But I’ve watched the disparity between the gosh-wow stuff and reality for most of my life… and it doesn’t really matter whether it’s some loopy individual inventor or an entity like LM doing the gosh-wowing.

Make it work, first, fellas.

Buck_Godot · March 2, 2015, 10:51pm

Well it looks like we’re making progress on the fusion front. For the last 50 years, fusion was 15 years away, now we’ve reached the point where fusion is 2 years away, although it will probably stay there for the next 20 years.