scaleablity of a reactor?

[annodomini2]

Anyone considered using the capacitors themselves for shielding?

Other than possible dielectric breakdown, is there anything else that may suffer from this approach?

[Aeronaut]

annodomini2 wrote: Anyone considered using the capacitors themselves for shielding?

Other than possible dielectric breakdown, is there anything else that may suffer from this approach?

I sketched out a similar idea a few weeks when the pix started coming out. You could save a lot of plate steel by using an octagonal water jacket with 4 of the sides doubling as a common wall for 3 of the caps. This would reduce the shielding effectiveness due to not having a continuous boron and lead shield around the entire reaction chamber.

This would help make a smaller and lighter design but is a public relations nightmare because that would raise the operating radioactivity levels above background levels. I went with mounting the caps, charging, trigger controllers, and high voltage/high current parts on a sleeve that slides over the proper 3 layer shielding.

[annodomini2]

Aeronaut wrote:

Anyone considered using the capacitors themselves for shielding?

Other than possible dielectric breakdown, is there anything else that may suffer from this approach?

I sketched out a similar idea a few weeks when the pix started coming out. You could save a lot of plate steel by using an octagonal water jacket with 4 of the sides doubling as a common wall for 3 of the caps. This would reduce the shielding effectiveness due to not having a continuous boron and lead shield around the entire reaction chamber.

This would help make a smaller and lighter design but is a public relations nightmare because that would raise the operating radioactivity levels above background levels. I went with mounting the caps, charging, trigger controllers, and high voltage/high current parts on a sleeve that slides over the proper 3 layer shielding.

Which type of radiation, neutons or x-ray? (again have I missed something?)

[HermannH]

annodomini2 wrote:
Which type of radiation, neutons or x-ray? (again have I missed something?)

Both are generated. In fact x-rays make up about half of all the energy that is generated. The design of the system is meant to capture the x-rays and convert them to electricity like a solar cell.
However, a small amount of neutrons is also generated in a side reaction to the main p11B reaction. For details see Aneutronic fusion.

[JimmyT]

I think that the ability to switch capacitors out is probably important. I believe this will be one of the most frequent failure modes. (Besides switches and electrode erosion). I do wonder if Eric has any info on capacitor longevity. And how dependent is it on the number of discharges vs simply the age of the capacitors? How heavily dependent is it on capacitor operating temperature? My personal experience is that inductance units seem to suffer from overheating more than do capacitors. But that’s just with little electronic stuff. Ham radios and such.

Another thing to keep in mind is that once mass production is approached fewer larger capacitors might make more sense. Companies would be happy to make them in million lot batches. Or maybe the total capacitance can be a bit smaller. Maybe only 10 capacitors of the current size will be optimal.

Lots to sort out once the data starts coming in.
Interesting line of thought though. We need to get them to fit in those modular shipping containers, if at all possible.

[annodomini2]

From what I understand the plan is to use some mechanism to convert the x-rays into usable energy? So the mechanism used here could be the shielding here could it not?

So is the biggest concern the neutron emissions?

[HermannH]

annodomini2 wrote: From what I understand the plan is to use some mechanism to convert the x-rays into usable energy? So the mechanism used here could be the shielding here could it not?

So is the biggest concern the neutron emissions?

That’s right.
The proposed setup is one meter of water to slow down the neutrons followed by ten centimeters of boron to absorb them.

[JimmyT]

The neutrons really are the main concern.

The water is important. It turns out that particles transfer their momentum most effectively to other particles of similar mass. Hence the hydrogen in the water molecules is more efficient at slowing down neutrons than a similar mass of concrete. Or even lead. And once the neutrons are slowed down (Thermalized) boron atoms have a very large capture cross section.

The point being that the x-ray conversion system may not be that good at slowing down neutrons as it will be made of heavier (Higher z) materials.

[belbear]

JimmyT wrote: Rematog,

I’m reluctantly forced to agree with you about the probability of regulation. It is interesting to note, however, that all the safety issues discussed do not involve the reactor. But rather the high voltage transmission equipment. And this equipment is present at all power facilities, be they coal powered, hydroelectric, etc.

I think regulation of FF reactors is inevitable.

Compare with aviation:
100 years ago, everyone could build and fly his own flying crate using bedsheets and broomsticks. With many deadly consequences.
Nowadays, everyone still has the right to own, fly and even build an aircraft, as long as machine, pilot and constructor comply with an ever growing list of FAA regulations.
But these regulations still permit private aviation, for fun or profit. Despite it’s not as cheap as it could be without regulation, at least it’s safe.

As long as regulation is for safety purposes, there should be no objection against it.
The goal must be to insure that any privately owned fusion equipment does not pose any electrical, radiation or chemical hazard to its operators and the general public, and to insure that only qualified people build, operate and maintain it.
After all, A FF generator IS a dangerous piece of equipment, operating with ten thousands of volts, lethal radiation and poisonous substances like decaborane.
So a regular inspection by some sort of organisation (DOE or others) to insure that everything is safe and sound may be desirable, just like with airplanes.

In other words, I would not mind a FF plant next door, but then I want to be confident that their 40000 volts do not come jumping out of my power sockets because the greedy owner cuts back on maintenance.

What should not happen is a very restrictive regulation, like with nuclear fission (for THAT there is a good reason), that prohibits private persons and small companies from owning and operating a focus fusion reactor unless they comply with regulations made to the measure of big power companies like the ones that now operate fission plants.
These big companies WILL oppose focus fusion, if only because their expensive investments in current power sources are at risk.

The media also plays an important role in the early days of commercial FF power. If they happen to scare the general public with horrific comparisons a la Chernobyl or Harrisburg, out of pure ignorance and sensationalism, the government may feel the need to respond.

Okay, I’m a European, so I may incline somewhat more toward the need for government regulation than the average American does.
And we all know what happened to Wall Street and the banks because of “deregulation”

[Breakable]

It would be interesting to see the FF reactor to go open source, and people building one for their own community in 10-15 years. I wonder if the laws would allow that.

[Tulse]

Breakable wrote: It would be interesting to see the FF reactor to go open source, and people building one for their own community in 10-15 years.

Perhaps it’s a misperception on my part, but it seems to me that one of the most exciting things about focus fusion is its relatively technical simplicity. That’s not to say that there is not a lot of very hard work needed to do the research and get it operational, but if/when it does work, the actual device appears pretty simple, arguably much simpler than any other fusion design, and simpler even than most power generation technologies. All of the individual technological pieces are pretty well understood and easily produced to whatever specs one needs. My guess is that, once there is a demonstration of substantial over-unity energy from FoFu, it will be very difficult to prevent these devices from popping up all over the place. (I suppose that’s a real risk for the business side of Lawrenceville Plasma Physics — if this approach works, it may be so easy to reproduce that it is difficult for LPP to profit from.)

[HermannH]

One way for the big companies to stall adoption of FF by smaller entities is through tough regulations.

There is an interesting example of this in the US. The conversion of vehicles to run on natural gas is extremely expensive because of the high cost for a mechanic to obtain a license (apparently $200,000 per engine type per year).

So there is going to be intense lobbying for and against crippling regulations, depending on which side you are on.

On the other hand, it’s a global economy. If FF turns out to deliver cheap energy countries that adopt it without significant restrictions will enjoy an advantage. Governments in countries with severe restriction will face intense pressure from consumers and some industries to reduce regulations to ‘reasonable’ levels.

One possible outcome as Rematog maintained all along is that, at least initially, FF will be installed mostly in large facilities (i.e. retrofitted power plants and large industrial plants that need lots of power). In these places the overhead to comply with regulations is relatively low.

[belbear]

Besides governmental regulation, there may also be a strong influence from existing power and oil companies (a powerful multi-trillion $$ business)
In developed countries such as the US and Western Europe, especially the oil lobbies are very strong and will oppose focus fusion. And their CEO’s are NOT democratically elected!

Fast-growing countries such as China and India on the other hand, have no such inhibitions. If their government finds focus fusion useful, they will simply use it to the maximum possible extent.

At present, These countries have to import most of their fossil fuels (except coal) and thus have no other choice than to generate ever more electricity using new polluting coal plants or landcape-devastating hydropower.
I’ve been in China this year and I noticed that petrol there is extremely expensive compared to the average Chinese income. It’s more or less the European fuel price. As a result the Chinese are using much more electric vehicles than we do. In places like Beijing and Shanghai, electric scooters are the rule, not the exception.

All these rapidly industrializing countries will welcome focus fusion with open arms, and not only because it makes dirty coal plants obsolete.
Focus fusion will also diminish the need for a new, more powerful electricity grid (through decentralizing the fusion plants) and reduce the need for fossil fuel import because using electric vehicles and appliances will become even cheaper and ships can use focus fusion directly.

Chinese may well be the first to mass-produce focus fusion reactors. After all, if they can copy an iPhone, they can copy a fusion reactor.

A bad scenario:

While there may be el-cheapo made in China “fusion-in-a-box” units already shipping worldwide, our own lobby-driven regulations may prohibit us from buying them. Except for the military, of course. THEY will use focus fusion to upgrade their nuclear subs and carriers. (and dieselelectric vessels too)

A good scenario:

Multiple, competing companies selling “fusion-in-a-box” units with a mandatory maintenance contract to anyone who wishes to invest in them.
Every so-often a qualified technician comes by, opens the hermetically sealed unit, checks everything out, replaces worn parts such as electrodes, and replenishes the fuel supply. In addition, a small bottle of recuperated helium may also be replaced with an empty bottle.

“Unauthorized opening of this reactor core is a federal crime and will be legally proscecuted.” 🙂

I don’t think DIY “Mr.Fusion” kits will become a likely option in the near future.

[msmith]

Scalability of a reactor?

What about the pulse rate?
If 330 Hz produces 5 MW could the pulse rate be dialed up to 660 Hz with output at 10 MW?
How about 3.2 GHz with output at 48 TW? 😛

[HermannH]

msmith wrote: Scalability of a reactor?

What about the pulse rate?
If 330 Hz produces 5 MW could the pulse rate be dialed up to 660 Hz with output at 10 MW?
How about 3.2 GHz with output at 48 TW? 😛

Nice try, but the maximum rate is largely determined by the ability to cool the system. Just like computer chips.

[Author]

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