General Fusion in the news

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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D Tibbets
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Re: General Fusion in the news

Post by D Tibbets »

General Fusion, are they targeting D-D fusion. If so the neutrons will account for ~ 50% of the fusion energy yield, not 5%. And if they are using lead, I seem to recall that lead is one of the neutron boosters that have been suggested for tritium production in Tokamaks. I don't know if it is the common lead isotope but apparently for each neutron absorbed, the resultant isotope decays with several neutrons emmited, thus amplifying the available neutrons- good when you need them to produce excess tritium for feeding D-T Tokamaks, but bad if material degradation and secondary radiation is the concern.

Lets see. non mainline fusion pursuits include:
Tri Alpha- apparently well funded
Other FRC research -? funding
General Fusion - well funded
Dense Plasma Focus- poor funding
EMC Polywell and possibly Lockheed Skunk Works variant- unknown funding

Secondary fusion harvesting- solar cells- continuous evolutionary improvements in efficiency and costs may end up being economically competitive.

If I was a Tokamak/ ITER fanboy, I would be a little nervous. If I was a fossil fuel (especially coal) executive I would also be nervous.

Of course if any of these things actually work economically it will take decades to penetrate deeply into the markets, so I would be only slightly nervous if I was a coal executive. Job security in the Tokamak community may be more acutely threatened.

Dan Tibbets
To error is human... and I'm very human.

93143
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Re: General Fusion in the news

Post by 93143 »

I thought it was D-T. Hence the molten lithium mixed in with the lead; that's where they get their tritium...

You couldn't ask for a better neutron shield than a multi-metre layer of this stuff. If the compression event results in significant amounts of it transiently surrounding the entire fusion plasma (I don't see anything else giving good compression), the injectors won't have to deal with the full flux either. The General Fusion concept seems to solve the first-wall problem by simply leaving out the first wall entirely...

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

Yes, the main fusion mode is D-T, not D-D, but D-D net gain is a milestone:
Making affordable fusion power a reality.
• Founded in 2002, based in Vancouver, Canada
Plan to demonstrate proof of physics DD equivalent “net gain” in 2013
• Plan to demonstrate the first fusion system capable of “net gain” 3 years after proof
• Validated by leading experts in fusion and industrial engineering
• Industrial and institutional partners
• $42.5M in venture capital, $6.3M in government support
From website:
Key Advantage: Thick Liquid Metal Wall
The thick liquid metal wall surrounding the fusion reaction in General Fusion’s system is a major practical advantage.  The energy from the fusion reaction is absorbed by the liquid metal, shielding the steel sphere and preventing damage.  As it is absorbed, the energy heats the liquid metal and the hot liquid metal can be used to create steam, a convenient way to extract the fusion energy.  The lithium in this same liquid metal is also easily bred into the tritium fuel required for ongoing operation.
Counting the days to commercial fusion. It is not that long now.

D Tibbets
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Joined: Thu Jun 26, 2008 6:52 am

Re: General Fusion in the news

Post by D Tibbets »

Indeed, I now appreciate that D-T is the target fuel. And with lithium in the surrounding blanket, neutron damage to more distant structures may be well suppressed. I wonder how much of this lead +lithium rotating layer is for reactor function, and how much it is for tritium production. If both functions are covered by this single stage, then it would be a feather in their cap. Considering the size and coverage of the lithium+ lead layer, with the spinning helping to cover the near polar regions (while keeping the more equatorial portions pushed out) it would seem to have a huge advantage over Tokamak lithium blanket engineering challenges. Also, I think that the extremely challenging diverter needed for Tokamaks is avoided.

If their tests/ computer models are showing that symetrical compression of sufficient magnitude is reasonable, I start to see why their funding has reached hundreds of millions of dollars.

Dan Tibbets
To error is human... and I'm very human.

swamijake
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Re: General Fusion in the news

Post by swamijake »

I'm pretty sure they do not have hundreds of millions of dollars funding. I think it is about 30 million. It is a mixture of public funds through STDC (gov of Canada research investing arm), VC (Chrysalix and others), and private funding. They may have commitments for further investment pending results of the minisphere with injectors testing. Canada, and BC in particular, also has a very attractive tax regime for research and development. While you still need success to make money on the investment, the tax benefits greatly reduce the sting if the research doesn't go anywhere.

They have some interesting funding sources including Cenovus, a large tar sand oil developer. Cenovus has deep pockets. I'm sure if they produce enough neutrons to match their modeling the 100 MW test reactor will not be hard to fund. May be hard to find a good place to build it, but that will be a good problem to have.

Its kind of funny, the best possible outcome with the minisphere test is that they irradiate the hell out of all their equipment....

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

swamijake, re:
Its kind of funny, the best possible outcome with the minisphere test is that they irradiate the hell out of all their equipment….
Are you saying they will be able do collapse the vortex to target fusion conditions using a liquid other than liquid lead? What liquid could they use?[/quote]
Counting the days to commercial fusion. It is not that long now.

swamijake
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Re: General Fusion in the news

Post by swamijake »

No, they are using lead. Plan according to their website is eventually to use a molten lithium/lead mix to breed tritium as they go.

paperburn1
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Re: General Fusion in the news

Post by paperburn1 »

General atomics news
http://www.theengineer.co.uk/channels/p ... 18.article
superconductors away.
I am not a nuclear physicist, but play one on the internet.

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

swamijake wrote:No, they are using lead. Plan according to their website is eventually to use a molten lithium/lead mix to breed tritium as they go.
Then there should not be irradiation of the General Fusion companies' apparatus, no? From the General Fusion website:
Key Advantage: Thick Liquid Metal Wall
The thick liquid metal wall surrounding the fusion reaction in General Fusion’s system is a major practical advantage. The energy from the fusion reaction is absorbed by the liquid metal, shielding the steel sphere and preventing damage. As it is absorbed, the energy heats the liquid metal and the hot liquid metal can be used to create steam, a convenient way to extract the fusion energy. The lithium in this same liquid metal is also easily bred into the tritium fuel required for ongoing operation.
Best regards,
Mike
Counting the days to commercial fusion. It is not that long now.

crowberry
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Re: General Fusion in the news

Post by crowberry »

The Fusion Power Associates held their annual meeting on the 10th to 11th of December 2013 in Washington. General Fusion attended the meeting also this year and presented their status. The slides are up on the website at
http://fire.pppl.gov/fpa_annual_meet.html#2013. The GF presentation MTF Progress Update and Compression Heating of Spheromaks - Doug Richardson, General Fusion is here http://fire.pppl.gov/FPA13_Richardson_Gen_Fusion.pdf.

Slashdot posted this article about GF http://tech.slashdot.org/story/13/12/30 ... ral-fusion.

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

Thanks a million crowberry for those links, and you were right that these guys haven't gone "dark." In fact, Richardson's presentation that you provided the link to (repeated):
http://fire.pppl.gov/FPA13_Richardson_Gen_Fusion.pdf
is as much as anyone could ever expect.
Counting the days to commercial fusion. It is not that long now.

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

Also, in the blog article crowberry linked to, there are two comments that I thought were revealing:
Another of my concerns with this piece of machinery was the level of accuracy required to align the piston cylinders. The final product will require 200 of them, and if the system is sensitive to misalignment it is easy to imagine how this could impact its reliability.
It came as a bit of a surprise that the precision required was actually less than I expected, 50 micron (half a tenth of a millimeter) should suffice, and in terms of timing, the synchronicity can tolerate deviations of up to 10 microseconds, ten times more than initially expected. This is due to a nice property that the GF research uncovered during the experiments: The spherical shock wave they are creating within the reactor chamber is self-stabilizing, i.e. the phase shift when one of the actuators is slightly out of line causes a self-correcting interference that helps to keep the ingoing compression symmetric as it travels through the vortex of molten lead-lithium that is at the heart of the machine.
So, it seems the 1 meter mini-sphere tests with molten lead have yielded important results.

and
To create plasma of the required quality, and in order to get it into place, the company constructed some more impressive machinery.  It is a safe bet that they have the largest plasma injectors ever build.

Admittedly, comparing this behemoth to the small plasma chamber in the upper left corner is comparing apples to oranges, but then this machine is in a class of its own.
When studying the plasma parameters, it turned out that the theoretical calculations actually lead to an over-engineering of this injector and that smaller ones may be adequate in creating plasma of the desired density. But of course creating and injecting the plasma is only the starting point.  The most critical aspect is how this plasma behaves under compression.
From the September 25, 2013 Richardson presentation in Japan, it looks like the plasmoid shape necessary to reach their injection compression and longevity target is the "chalice" shape. From the September 2013 "Clean Break" article, Richardson was quoted as saying,
We’ve struggled with getting the confinement and we’re probably at half of what we need.
So, comparing this statement to the plasma triple product graph on the September 25, 2013 FPA13_Presentation projected progress GF has made impressive strides this year, and it would seem to justify Richards cautionary statement,
Have we gotten to net-gain fusion conditions yet? No. Do I still believe we can get there? Yes. Has it taken longer than expected? Yes. Fusion is hard.
Maybe their plasma injector will be there first quarter 2014?
Counting the days to commercial fusion. It is not that long now.

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

Next Big Future has a January 01, 2014 article on General Fusion's Japan presentation.
http://nextbigfuture.com/2014/01/genera ... .html#more
It seems to me NBF has got the projected progress graph x-axis meaning wrong. It can't be month and year as test data points exist for 2017 based on NBF's x'axis interpretation. What I think is the last date on the x-axis is Dec 18, 2013, then work backwards to put years to dates. Or, possibly, the dates on the graph are completely bogus. I can't figure which it is though.
Counting the days to commercial fusion. It is not that long now.

crowberry
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Re: General Fusion in the news

Post by crowberry »

The progress graph is on page 48 of the slide set from Japan. It is true that the graph is logarithmic and that the shown growth is faster than exponential. The headline says 2013-2014, but it is true that the x-axis of the graph is funny since it covers partly five years. Maybe the leftmost date November 14th is for 2012. Then February 15th would be 2013 and the rightmost date would be December 18th 2016. So I think you are right that the NBF got the dates wrong.

mvanwink5
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Re: General Fusion in the news

Post by mvanwink5 »

I took the graph to apply to plasma generation efforts needed to support demonstrating that net fusion can be reached with their full scale components, not the whole project full scale components assembled and tuned for net fusion. If that view is correct, then the time placement of "chalice" shape which has already been determined experimentally to be required, plus the data points and their placement (experimentally determined), would imply that most of the graph represents the past. Also the vertical line on the graph (where dramatic test pictures are placed adjacent) would indicate a point in the past. Further, the days which were interpreted by NBF as years are inconsistent with the month progression which is sequential. In addition, based on a recent interview with Richardson, the plasma compression seems to be further along (0.5 of needed density) and nearing the goal of net.

I suspect where GF is in plasma testing is where they are scaling up their tests to reach net at the upper right (edit) side of the graph. But then again…

So, GF is not leaving us in the dark, but I can't say I know where they are either, and am left with just guesses. Unless you have some insight…

I am hoping they reach net plasma triple product first quarter 2014 and trigger next round of money and building the net device.
Counting the days to commercial fusion. It is not that long now.

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