What do we know about WB-100?

[JohnP]

Aero, You are correct, a strong B field is the trick.

All right, I see it now. I had to go back to the WB6 numbers and crank it through again. WB6 was tested at fields of about 1300 G. If you can manage coils in the 20-30T range, that will theoretically just about balance the output power with the input drive power.

But Jeez Louise! Between the mechanical stresses of the magnets and the heat load of all that power packed in that small volume, could it survive more than a couple brief tests? Sure is fun to think about though.

[Jboily]

Well shucks... I was hoping for something applicable to over the road trucking as I have heard that that industry uses ~25% of our petroleum. Half meter radius is really good, but intermittent operation is really bad.

I think it is possible with clever design to make a small net power fusion, but it still would not be economically viable. Unless we can drop the price of a reactor down to $200K for a low maintenance 200Kw machine. Combustion engines are not so expensive, this is what you have to compete with.

In any cases, I am not sure if I want the truckers around here to have a nuclear reactor in the trunk. Many are not that good a driver.

I think the solution for this is a fuel cells (Ballard?), using Hydrogen as fuel that would be produced using electricity from large fusion reactors. The exhaust is clean water, and the convention efficiency Hydrogen to electricity in a fuel cell is above 90%!

[blaisepascal]

I think the solution for this is a fuel cells (Ballard?), using Hydrogen as fuel that would be produced using electricity from large fusion reactors. The exhaust is clean water, and the convention efficiency Hydrogen to electricity in a fuel cell is above 90%!

There is a lot to be said for a high-energy-density liquid fuel, and hydrocarbons work real well with our infrastructure.

Burning hydrocarbons yield water and CO2. How hard is it, assuming cheap electricity, to reverse the process, and react water and CO2 (and energy) to get some form of hydrocarbon?

[Jboily]

But Jeez Louise! Between the mechanical stresses of the magnets and the heat load of all that power packed in that small volume, could it survive more than a couple brief tests? Sure is fun to think about though.

Just as a conversation piece, here is a very rough estimate for a 0.5 meter, 6 cryogenic coils device, neglecting a lot of parameters;
10 T, Wb=0.5 meter, would produce about Pf=60Mw, with close to 15 Mw net power. Surface heat load at about 1.4Mw/M^2. For operation longer then a few milliseconds, cooling would be required, but surface heat load is still half of the Wb100.

[Jboily]

Burning hydrocarbons yield water and CO2. How hard is it, assuming cheap electricity, to reverse the process, and react water and CO2 (and energy) to get some form of hydrocarbon?

Well, just plant a seed. I think there are a few processes, like some developed at NASA for long interplanetary trip. But it is costly. It easier to do it with plants.
It is not clear that this is a viable long therm solution to use plants as fuel, we might end up to have the choice between starvation and locomotion
Fuel like Hydrogen is much cleaner, and fuel cells have 3 or 4 time better efficiency. Infrastructure can be changed in a 10 to 20 years period.

[Roger]

Guys, building a little bit larger machine will cost a lot more money,

Exactly. Building these reactors (all DD)

1) Dodec, The same over all size as WB-7
2) LN2 cooled, The same over all size as WB-7
3) Twice the size of WB-7 (60cm)

How about a 60 cm dodec.

I think I just spent like 150-200 million.

Which may be why some arrive at the arguement that we should just go ahead and build the big one.

Sure these smaller machines would serve a useful purpose, but so does going right to a net power reactor.


Do I have it right that only one fusion reactor has achieved net power, and if so, then by Dr Nebel going for net power, means WB-8 could be the second reactor to ever achieve net power.

I believe a net power WB-8 would generate significant political leverage. I'm guessing that Dr Nebel has given the thought some consideration too.

[Torulf2]

If it have same diameter for the coil-rings and is a dodek…
The radius, volume for the magrid becomes significant larger.

[Jboily]

Guys, building a little bit larger machine will cost a lot more money,

Which may be why some arrive at the arguement that we should just go ahead and build the big one.

Just to make sure I am understood here, I am not saying that a 0.5m should be build, I am just saying that a 1.5m has a good net power margin. It is not necessary to go larger and spend a lot more money, just to make sure we get to net power.

[Roger]

I dont know if you were referring to my comment.

If it have same diameter for the coil-rings and is a dodek…
The radius, volume for the magrid becomes significant larger.

I said, same overall size, keeping the magrid volume nearly the same.

[Aero]

I wonder if we are on the same page regarding the objective of WB-100? What is the objective and what should it be?
Sure, WB-100 is a proof of concept machine, but if that is all it is, and we use 5 years to prove the concept, then that just makes us 5 years further behind in our energy dependence on foreign oil. And then what if we are wrong by 50% on net power? We have a 50Mw machine that we really need to scale up to go commercial.
What should it be? It should be the fastest path to a commercial scale BFR, and that means bigger, first to eliminate scaling risks now and later, and second to establish the knowledge base to build commercial scale machines, machines that will actually allow a positive reduction of our oil import bill. The first commercial BFR's will be heat generators, the output will be heat. Later machines will generate energy in other forms.
Straight to net power? No! Straight to commercial power, Yes.
Oh, and the argument that bigger costs more looses sight of the fact that every calendar day lost in weaning ourselves from foreign oil costs this nation over a Billion dollars. How much does 5 years cost? The Commercial scale BFR is a weaning machine!

[Rick Brice]

Aero,

Well said!

I think we should put neutrons behind us and think alpha particles.

[Roger]

I wonder if we are on the same page regarding the objective of WB-100? What is the objective and what should it be?
Sure, WB-100 is a proof of concept machine, but if that is all it is, and we use 5 years to prove the concept,

If WB-100 is to be a DD pulse mode non SC magnet device, that goes to net power, that barely meets the definition of proof of concept. If funding was secured tomorrow, I doubt it would be 5 years. I wanna see University's get involved.

If WB-7 was good enough to move forward, then there might be a serious advantage to having DR Kulcinski @ the University of Wis @ Madison build a dodec or Simons LN2 cooled convincer. AS Well as getting Urbana in on it.

Then we can deal with the Dodec issues, PB-11, and scaling in probably well under 5 years. And we are then in a position to assess our position, and move forward based on those multiple projects.

We shall see.

[Aero]

Roger, you may be right, it seems that more avenues of research would hurry things along and I am all for that. You see, I think the BFR is going to work. Oh sure, maybe there is a non-linearity that will twist on us and cut us off at the pass, but the physical world is rarely like that. And if there is a unknown, hidden and also unsuspected twist to be uncovered, we still want to discover it as soon as possible. As Dr. Nebel would say, there could be a work-around.

On the other hand, the down side is that more research labs involved will result is the "Design by Committee" syndrome, adding time to the development. And I think that a 2 meter radius trun-cube will generate a lot of power and if so, it is going to be cheaper power than we can get from any other source, including cheaper than Hydro. Personally I'd rather see a Dodec, much more elegant, but I don't want to wait for anything that is 6 months farther down the road.

Problem is, that is not my or an EMC2 decision. The money people have to decide who and how much research to do. And the researchers need to decide that there are no "boogy-men" waiting to jump out of the physics and destroy their reputation. Unless they can point to a true show stopper from the peer review, its time to put reputations on the line and go for it, go for it in a big way.

[djolds1]

Sure these smaller machines would serve a useful purpose, but so does going right to a net power reactor.

OTOH jump straight to top level and make a major error, and you blow your credibility. And your budget. Slow scale up allows easier preservation of credibility and lower reboot costs if/when inevitable errors and mistakes creep into the process.

Do I have it right that only one fusion reactor has achieved net power, and if so, then by Dr Nebel going for net power, means WB-8 could be the second reactor to ever achieve net power.

I believe a net power WB-8 would generate significant political leverage. I'm guessing that Dr Nebel has given the thought some consideration too.

I believe the question you're asking Roger is "where dost I signest thy NDA?"

Duane

[Aero]

Duane wrote:

OTOH jump straight to top level and make a major error, and you blow your credibility. And your budget. Slow scale up allows easier preservation of credibility and lower reboot costs if/when inevitable errors and mistakes creep into the process

Well, major errors do happen, look at the Hubble and its fuzzy vision when first launched. But they didn't discard the Hubble and they wouldn't discard the BFR. Rather they would use what's salvageable (most of it, I'd bet) and the lessons learned to fix the area that was flawed. You see, I believe that the BFR will work. If you don't believe that then all you are doing is stretching out the cash cow and not helping America at all. Of course, believing that it won't work is not the same as believing that our current team can't make it work. But I think they can and will.
As for slow scale-up, well with a billion dollars a day spent on foreign oil, I suggest we go faster than that. The nation truly cannot afford "slow."