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Skunk Works Reveals Compact Fusion Reactor Details

aviationweek.com

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Re: Skunk Works Reveals Compact Fusion Reactor Details

#81

Post by akavel »

robin_reala wrote: post #28

“the first reactors […] could be ready for use in a decade.” I’m sure I’ve heard that somewhere before…

I have the link to xkcd 678 "Researcher Translation" bookmarked for those occasions. Quoting the appropriate row here:

    If a researcher says a cool new technology should be
    available to consumers in... -> what they mean is...
    [...]
    ten years -> "we haven't finished inventing it yet,
                  but when we do, it'll be awesome."

Re: Skunk Works Reveals Compact Fusion Reactor Details

#82

Post by orkoden »

seren wrote: post #38
orkoden wrote: post #33

Earlier quoted context omitted.

If they can manage to build what they envision we will have tanks with with laser weapons.

On a similar vein, I wonder what are the strategical consequences of such an advance. Assuming it works as described in the article, do you allow the technology to be exported ? Because a whole fleet of fusion air carriers, battleships, submarines and bombers versus a conventional army has plenty of implications in term of autonomy, reach, etc. But on the other hand, there is a such demand for energy everywhere that…

CFR compact fusion reactor (http://aviationweek.com/technology/skunk-works-reveals-compa...) size: 23 X 43 ft. power: 100 MW

Energy use of the US (2011): 25,484 TWh Power needed: 2,900 GW = 25,484 TWh / 365 / 24 h * 1000 Number of 100 MW CFRs: 29,000

Civilian use will happen. The benefits are just much to great. There will be regulation and oversight for them. But you won't need one in every truck. It's overkill. As you can see from the above calculation 29 thousand CFRs could cover all the US energy needs. So there will be hundreds of thousands worldwide. It will be hard to keep all of them under control But this would basically solve all of humanities energy problems and decrease CO2 production, and destruction of the environment from mining immensely.

Having large amounts of energy available enables new weapon systems to become feasible: high powered lasers, coil guns and rail guns. They can be added to any air, land, or sea vehicle that's above the size of a small truck.

Ships are pretty large anyway and aren't as restricted as land or air vehicles when carrying big machinery. Aircraft carriers won't change so much. You can build them a little smaller and their defensive weapons might improve. Nuclear submarines otoh could be built as small as modern diesel powered subs like the Dolphin class.

You could build a drone with an extremely long loitering time. If it uses a laser or rail gun, it will also have lots of ammunition. Instead of carrying a couple of hellfire rockets and having to refuel after several hours it could stay in an area for months.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#83

Post by z92 »

DennisP wrote: post #65
27182818284 wrote: post #42

> could be ready for use in a decade. That's the standard issue joke. "Nuclear fusion has been just ten years away for the last fifty years" It is so common as a joke I'm surprised the article didn't mention it.

No, the standard joke is "thirty years away." Or at least it was. Strangely enough the number keeps decreasing with the passage of time.

Plotting a "Year vs Years away" graph would then give us a good estimation on when we can expect to meet that expectation.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#84

Post by bulltale »

wcoenen wrote: post #57

> 100-megawatt reactor measuring seven feet by 10 feet, which could fit on the back of a large truck A typical thermal power station has an efficiency below 50% for electricity generation, so the plant dissipates at least as much heat as it generates electrical power. I wonder how you could get rid of 100MW of waste heat from a volume small enough to fit on a truck. That's a heat flux of more than a megawatt per squa…

In addition, in the step before where the heat is transferred away from the reactor walls to the turbines, a heat flux is needed of 100MJ/s. Assuming a contact surface of 100m2, that is 1MJ/s per m2. That sounds like a huge flux and I am not sure if there is any medium that could do this.

Or are my assumptions way off?

Re: Skunk Works Reveals Compact Fusion Reactor Details

#85

Post by festivusr »

cowkingdeluxe wrote: post #53

"McGuire said the company had several patents pending for the work and was looking for partners in academia, industry and among government laboratories to advance the work." I'm guessing this means that they will try and maximize profit rather than maximize cheap and clean energy for the entire world. That is a bit disappointing if true.

They're a for-profit company.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#86

Post by DennisP »

[deleted] wrote: post #80
raverbashing wrote: post #63

Earlier quoted context omitted.

From what I've heard, the reactor actually outlives the ship, no?

[deleted]

Civilian power reactors need refueling at about that pace, but Nimitz-class carriers "are capable of operating continuously for over 20 years without refueling"

http://en.wikipedia.org/wiki/Nimitz-class_aircraft_carrier#P...

Re: Skunk Works Reveals Compact Fusion Reactor Details

#88

Post by KhalilK »

dweinus wrote: post #79
KhalilK wrote: post #24

Meanwhile, work on an actual fusion reactor continues; http://www.iter.org/newsline/-/2020

From the article: "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…

From the article ?

Re: Skunk Works Reveals Compact Fusion Reactor Details

#90

Post by hangonhn »

cowkingdeluxe wrote: post #53

"McGuire said the company had several patents pending for the work and was looking for partners in academia, industry and among government laboratories to advance the work." I'm guessing this means that they will try and maximize profit rather than maximize cheap and clean energy for the entire world. That is a bit disappointing if true.

Profit and good of the world need not be opposites. In fact they tend to go together if the company is going for the long run.
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