I WANT to build a nuclear reactor.

AI Thread Summary
Building a nuclear reactor for a science fair project is deemed impractical and illegal due to stringent regulations and safety concerns. Participants emphasize the necessity of obtaining a license from the Nuclear Regulatory Commission, which involves extensive documentation and financial commitments. Alternatives like creating a non-working model of a reactor or building a fusor are suggested as safer and more feasible projects. The discussion highlights the potential legal repercussions and the attention from government agencies that such projects could attract. Overall, the consensus is to pursue a less hazardous and more manageable scientific endeavor.
amberb617
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Ok so I know that this seems like an absolutely absurd and almost impossible idea but I want to build a nuclear reactor to enter in the state science fair next year.

I know that it takes time, wit and money but I'm completely prepared to take on the challenge.

So the point of posting this bulletin is to call on the help of the wonderful members of this Physics Forum.

I need to be enlightened.
Help me.
:rolleyes:
 
Engineering news on Phys.org
I'm usually very supportive of ambitious projects but honestly, choose something else to do. The litigation is too much and the safety and security is nothing a single person can handle.
 
Do google "build your own nuclear reactor".

will give you lots of hits.

but the thing is, how are u getting hold of radioactive materials?

I would recommend building a cyclotron or an accelerator, which could actually work pretty much better than an entire reactor...
 
If you're in the US, whatever you end up building (whether a reactor or cyclotron), if it has the potential to produce ionizing radiation, it will require a radioactive materials license which can be quite expensive depending on where you live. The licensing requires that you have a radiation protection program, are qualified by education and experience to possesses radioactive materials or radiation producing machines, etc. As was stated, you're probably better off trying something else. Unless, of course, you mean you want a non-working model of a reactor, in which case it's doable, though still quite an undertaking.
 
amberb617 said:
Ok so I know that this seems like an absolutely absurd and almost impossible idea but I want to build a nuclear reactor to enter in the state science fair next year.
I know that it takes time, wit and money but I'm completely prepared to take on the challenge.
So the point of posting this bulletin is to call on the help of the wonderful members of this Physics Forum.
I need to be enlightened.
Amber,

I'm sorry - but a reactor is NOT a suitable "science fair" project.

If you had the technical accumen to handle this project, you would be working for a
reactor manufacturer or at a national lab; not entering a science fair.

Additionally, it would be illegal for you to build a reactor. In order to build a reactor, you
have to have a license from the USA's Nuclear Regulatory Commission. They will want
copious amounts of documentation on the safety of the reactor design. As a
requirement under the Price-Anderson Law, you would need to buy insurance from the
federal government, the minimum yearly premium is $2 Million.

Owning a nuclear reactor is a financial stretch even for a University. In fact, many
Universities have shutdown their reactors because it became too expensive; the
University of Michigan is one such case that comes to mind.

Building a reactor as a science fair project would be like building a jet airliner as a
science fair project; it's way too ambitious.

Set your sights on something more reasonable; you'll learn more, and have more fun.

Good luck.

Dr. Gregory Greenman
Physicist
 
amberb617 said:
Ok so I know that this seems like an absolutely absurd and almost impossible idea but I want to build a nuclear reactor to enter in the state science fair next year.
Amber,

I like the suggestion of "daveb" - that you make a model of a reactor.

That way you can learn about them; without having the daunting challege of producing
a working reactor. You could have a little model with control rods that you could withdraw
by hand; and that would cause a light bulb to go on/off. Put some type of blue filter
surrounding the light bulb to give the appearance of the blue Chrenkov radiation emitted
by an operating reactor:

http://web.mit.edu/nrl/www/reactor/core_description.htm

http://nscr.tamu.edu/

http://www.mne.ksu.edu/research/centers/reactor/Reactor%20Facilities/

There are lots and lots of books on nuclear reactors. You might also check to see if
any University in your region has a nuclear research reactor that you could tour.

Good luck with the science project.

Dr. Gregory Greenman
Physicist
 
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I concur with Morbius.

One needs a license to purchase or obtain and use "Special Nuclear Material" (in this case fissile material), and sorry, but students do not qualify. It takes years to get a license, and the NRC is not about to expedite one's application. It also takes years to become qualified to what one proposes.

seems like an absolutely absurd and almost impossible idea
NO - it is an absolutely absurd and impossible idea.

Best just to build a model as Morbius suggests.
 
daveb said:
If you're in the US, whatever you end up building (whether a reactor or cyclotron), if it has the potential to produce ionizing radiation, it will require a radioactive materials license which can be quite expensive depending on where you live. The licensing requires that you have a radiation protection program, are qualified by education and experience to possesses radioactive materials or radiation producing machines, etc. As was stated, you're probably better off trying something else. Unless, of course, you mean you want a non-working model of a reactor, in which case it's doable, though still quite an undertaking.

What about a fusor? Those can produce neutrons and plenty of x-rays and I don't think they are illiegal...

The construction of a farnsworth fusor wouldn't be absurd and can achieve nuclear fusion (even better than fission!). A hand full of amateurs have successfully built working (fusing) fusors in this country, including some very young people (well, not 6 year-olds). This would be an ambitious, but doable project IMHO.

You could also built a fusor demonstrator, a far less dangerous and costly version of the real thing, that would none-the-less show the principles behind electrostatic confinement. Basically you need a vacuum chamber and vacuum pump, a high voltage power supply, some stainless steel wire to make your anode and cathodes, and the knowledge to put it together.

What do the rest of you think?

-Alan
 
alancj said:
What about a fusor? Those can produce neutrons and plenty of x-rays and I don't think they are illiegal...
Alan,

If it produces ionizing radiation, then YES - IT IS ILLEGAL!

You have to be licensed by the NRC to operate an X-ray machine,
an accelerator, or possesses a radioisotope.

This is the only way that one can be sure that someone isn't producing
radiation that is irradiating unspecting people because the operator of
the source didn't consider proper shieldig...

If you don't know the laws, please refrain from giving advice to yourg
students who may follow it and get into trouble.

Dr. Gregory Greenman
Physicist
 
  • #10
I'm surprised that no one has mentioned the rather obvious problem with this:

Even in the preliminary steps of designing and creating this, you will acquire the full and complete attention of several branches of government including the FBI and DND as a "person of interest."
 
  • #11
DaveC426913 said:
I'm surprised that no one has mentioned the rather obvious problem with this:

Even in the preliminary steps of designing and creating this, you will acquire the full and complete attention of several branches of government including the FBI and DND as a "person of interest."
Dave,

Yes - the creation of a source of ionizing radiation is something that a terrorist; either
foreign or domestic; might try to accomplish for the purpose of terrorizing the populace.

Therefore, it is quite reasonable for the FBI and Homeland Security to be on the look-out
for any activities of this type.

Dr. Gregory Greenman
Physicist
 
  • #12
Even more surprising is the fact that most science fairs have explicit rules about things like nuclear material, human tissue samples, etc.You might want to look them up. Chances are, you'll never be able to get anything resembling a "homemade nuclear reactor" in the door, and you might well be disqualified.

You do not have the education required to safely handle radioactive material. You should not even be attempting this, since it will endanger your life and the lives of everyone around you.

If you want to be ambitious, try building something just as complex but less dangerous, like a linear particle accelerator.

- Warren
 
  • #13
chroot said:
If you want to be ambitious, try building something just as complex but less dangerous, like a linear particle accelerator.
Yeah, I built one of them last weekend. Made it completely out of MDF, amazing what you can do in a garden shed...:rolleyes:
 
  • #14
Hootenanny said:
Yeah, I built one of them last weekend. Made it completely out of MDF, amazing what you can do in a garden shed...:rolleyes:
Next time try it with your garden hose and aluminum foil works much better :smile:
 
  • #15
Under the Radiation Control for Health and Safety Act, the Public
Service Act, and the Federal Food, Drug, and Cosmetic Act, the
Assistant Secretary for Health in the Department of Health in the
Department of Health and Human Services (HHS) (which has been delegated
to the Food and Drug Administration), was given the responsibility to
develop a program of radiation protection which, in part, included
research and training concerning radiation hazards, recommendations for
radiation users, advice to States, information for the public,
performance standards for electronic products that emit radiation, and
regulations for the sale, distribution, and use of medical devices.
These programs are described in 21 CFR 1000 to 21 CFR 1050. Additional
information may also be found on the Center for Devices and Radiological Control Web site.
http://hps.org/publicinformation/ate/q2547.html

http://www.fda.gov/cdrh/radhealth/products/xrayparticulate.html

The AEC (predecessor to NRC and DOE) used to have authority for regulation of X-ray devices, but it was moved under HHS/FDA. Nevertheless, anything that produces ionizing radiation is regulated and one must comply with Federal and State laws. Ignorance of the law is no excuse. States have an office which regulates manufacture and use of devices, which produce ionizing radiation, so one should check with one's state government.
 
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  • #16
Hootenanny said:
Yeah, I built one of them last weekend. Made it completely out of MDF, amazing what you can do in a garden shed...:rolleyes:

Hey, don't laugh. All you really need is a cavity, a Sears vacuum pump, and some relatively simple electronics. I'm not talking about MeV here, but a couple of hundred eV would be attainable, and measurable.

- Warren
 
  • #17
The ITER Newsline recently referenced a high schooler who built a machine that causes fusion.

The article it references is here: http://search.ft.com/ftArticle?queryText=fusor&aje=true&id=070126006711
 
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  • #18
theCandyman said:
The ITER Newsline recently referenced a high schooler who built a machine that causes fusion.
Candyman,

Yes - I read about him while visiting my home town of Rochester Hills, Michigan:

http://research.lifeboat.com/teen.goes.nuclear.htm

This student attended the same school district that I attended. In fact, his school,
Stoney Creek High School; is about a mile from the neighborhood that I spent my
childhood years.

http://www.rochester.k12.mi.us/index.asp?school=23&name=Stoney Creek High School

Stoney Creek, the third high school in the system was not part of the district when I attended high
school. I'm a member of the 2nd graduating class of the district's 2nd high school; Rochester Adams Senior High.
[ For you pop music fans - that's Madonna's alma mater. ]

http://en.wikipedia.org/wiki/Rochester_Adams_High_School

http://www.rochester.k12.mi.us/index.asp?school=22&name=Adams High School

Dr. Gregory Greenman
Physicist
 
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  • #19
Whoa... a particle accelerator in your garage? whoa! that's so cool...:approve:

Can you send me a link where they show you how to do it hoot? would appreciate it much...:rolleyes:

And the guy who built the fusion reactor... Anyone know what became of him? what does he do now? that's so cool man... a custom made fusion reactor... :approve:
 
  • #20
Morbius said:
Alan,

If it produces ionizing radiation, then YES - IT IS ILLEGAL!

You have to be licensed by the NRC to operate an X-ray machine,
an accelerator, or possesses a radioisotope.

This is the only way that one can be sure that someone isn't producing
radiation that is irradiating unspecting people because the operator of
the source didn't consider proper shieldig...

If you don't know the laws, please refrain from giving advice to yourg
students who may follow it and get into trouble.

Dr. Gregory Greenman
Physicist

If it is illegal (a fusor), then apparently nobody cares, considering I have recently read about a teenager who built a fusor being profiled in popular science or mechanics. If it was a bust your door down offense then I doubt they would have published the article and not mentioned his arrest as a terrorist.

From fusor.net:

"The Neutron Club"

These people have operated a neutron producing fusor or fusion system.
(normally d-d fusion):

Richard Hull - 10e5 neutron mark 3/99
Scott Little
Joe Zambelli - Half mega mark 12/01
Tom Ligon
Michael Li - winner $75k Intel scholarship (fusor)
Mike Amann
Jon Rosenstiel - Mega neutron mark 10e6 11/02
Gerardo Meiro - First non-US neutron Club member
Phillip Fostini
Carl Willis - advanced activation work
Larry Leins - pulsed fusor work
Craig Wallace - winner $1.5k Intel 2nd place (Fusor)
Frank Sanns
Brian McDermott
Fergus Noble & Henry Hallam - first UK neutron members
Adam Parker - winner of $10k Alabama scholarship in science
Mark Langdon
Thiago Olson
Wayne Rodgers
Eric Stroud
Wilfried Heil & Noemi Zudor - Smallest fusor ~3" diameter
Raymond Jimenez

Notice the people who won money and scholarships with their neutron producing fusor.

It is a perfectly viable project for anyone ambitious enough to tackle it.

-Alan
 
  • #21
Well, whether it's illegal or not depends on a few things. If the levels of radiation are low enough, the fusor may not require a license. Since radiation producing machines and accelerator produced material are regulated by the state regulatory agencies it would depend on the state the person lives. I believe Wyoming, e.g., doesn't really have any operating regulatory agency (or at least not one that regulates nuclear pharmacies). As for any material, if the activity is below the exempted quantity, then anyone can possesses it (e.g., no one needs a license for Cs-137 in activity less than 10 microcuries). I couldn't find information on neutron source strength for a fusor, but if it's low enough, the regulatory agency won't be concerned about it.
 
  • #22
alancj said:
If it is illegal (a fusor), then apparently nobody cares, considering I have recently read about a teenager who built a fusor being profiled in popular science or mechanics. If it was a bust your door down offense then I doubt they would have published the article and not mentioned his arrest as a terrorist.
Alan,

There was a case a few years ago of a teenager who was attempting to build a nuclear
reactor by assembling a bunch of radioactive material that he obtained by opening the
sealed sources inside home smoke-detectors, for example.

http://www.dangerouslaboratories.org/radscout.html

When it was ultimately found out what the teenager was doing, the autorities did check out
his work and found that he had contaiminated his garage, his home, and his school with
radioactivity. Clean-up crews had to come in and decontaminate the mess that this
teenager made. Because nobody discouraged this teenager from conducting his ill
conceived science project, many people were exposed to radioactivity that they should
not have been exposed to, as well as the large cost of cleaning up a radioactive
mess.

Independent of what the law says, I hesistate to recommend a project that involves
potentially harmful activities to a student that I don't know. The teenager in Michigan
evidently pulled off this project successfully. That doesn't mean any teenager can do
the same.

I think it would be irresponsible to recommend a potentially harmful project to a student
that I didn't know well and knew that they had the technical acumen and maturity to
handle the project.

Dr. Gregory Greenman
Physicist
 
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  • #23
The_Thinker said:
And the guy who built the fusion reactor... Anyone know what became of him? what does he do now? that's so cool man...
Thinker,

The November 2006 article I posted from the Detroit Free Press listed him as a 17 year
old high schoold student. I would assume that he's finishing his senior year in high school.

a custom made fusion reactor..

I wouldn't call the "fusor" a "fusion reactor". The amount of energy that one gets from the
fusion reactions is dwarfed by the amount of energy one has to put into the device in the
form of electricity to make it operate.

The fusor is a little neutron-producing accelerator. Science has known how to do that
for decades. Accelerating particles enough to cause fusion isn't all that tricky. One
will find little neutron pulse generators such as these in practically any nuclear lab.
[ The "Neutron Club" that Alan mentions includes THOUSANDS of university students
that have taken nuclear laboratory courses. ]

The real problem is how to create fusion and come out with a net production of energy.
THEN you will have a device that deserves to be called a "reactor".

Dr. Gregory Greenman
Physicist
 
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  • #24
Morbius said:
I wouldn't call the "fusor" a "fusion reactor". The amount of energy that one gets from the
fusion reactions is dwarfed by the amount of energy one has to put into the device in the
form of electricity to make it operate.

The fusor is a little neutron-producing accelerator. Science has known how to do that
for decades. Accelerating particles enough to cause fusion isn't all that tricky. One
will find little neutron pulse generators such as these in practically any nuclear lab.

The real problem is how to create fusion and come out with a net production of energy.
THEN you will have a device that deserves to be called a "reactor".

Although I understand that that's a mainstream notion, it seems rather odd to me to require that a 'fusion reactor' release net useful energy, while there are plenty of examples of 'reactors' that don't ranging from the Princeton tokomak test reactor, to chemical reaction vessels, to the infamous scavenger hunt breeder reactor build in the 1999 University of Chicago scavenger hunt, or the more famous pile that was set up there at Stagg field in 1942. Moreover, fusors do, in fact, release energy, so an (admittedly highly unlikely) improvement in energy capturing technology would move them from 'not nuclear reactors' to 'nuclear reactors' which strikes me as rather odd.

Honestly, I don't think that a fusor is a particularly good idea for a high school science experiment. There are hazards from high voltage and radiation (if you actually get it up and running), and they're likely to be expensive (in the thousands of dollars.) Meanwhile, there are plenty of easier, more original, and more practical experiments possible.
 
  • #25
Moreover, fusors do, in fact, release energy, so an (admittedly highly unlikely) improvement in energy capturing technology would move them from 'not nuclear reactors' to 'nuclear reactors' which strikes me as rather odd.
A pot of boiling water releases energy, but not more than is added.

A fusor does not produce much more energy than put in.

Say this kid got 1 million neutrons (IIRC, the article claimed 200 K) and assuming that is half of the reactions, there would be 2 million reactions producing about 4 MeV/reaction for simplicity.

2 million reactions * 4 MeV/reaction * 1.602 x 10-13 J/MeV = 1.282 x 10-6 J

If the student applied, let's say 10 kW for 1 s, then the system used 10 KJ.

Now compare 10 kJ with about 1 micro-J. How practical is that for an energy source?

Fusors are fancy neutron generators, not energy sources.
 
  • #26
NateTG said:
or the more famous pile that was set up there at Stagg field in 1942. Moreover, fusors do, in fact, release energy, so an (admittedly highly unlikely) improvement in energy capturing technology would move them from 'not nuclear reactors' to 'nuclear reactors' which strikes me as rather odd.
Nate,

The 1942 Stagg Field reactor WAS a CRITICAL system.

It was in EVERY sense a REACTOR. It produced more energy than input. In fact, to
operate a critical fission reactor - there's ZERO input energy needed.

Additionally, because it was a critical system, the Stagg Field reactor could put out ANY
amount of power as long as it was cooled. There was no cooling system on this reactor,
which limited it to very low powers. But if the Stagg Field reactor were surrounded by
some type of vessel through which coolant could be pumped then it could have
generated much more power.

In fact, the Stagg Field reactor was a prototype, which led to the X-10 reactor at
Oak Ridge, which was a prototype for the production reactors at Hanford. The Hanford
production reactors produced significant amounts of power, and had cooling systems;
and they were just "scaled up" versions of the Stagg Field reactor.

So Fermi's Stagg Field reactor was a reactor in that it really could have produced power,
if you put a cooling system on it.

That's NOT true of the fusor. The output energy is INSIGNIFICANT compared to the
energy one puts into it. The fusor is an energy "sink" not a "source".

As Astronuc stated, a "fusor" is a nice little neutron source; but it's NOT a reactor.

Dr. Gregory Greenman
Physicist
 
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  • #27
I know all about the nuclear Boy Scout. And I never suggested anyone build a fission reactor or take apart thousands of smoke detectors. Obviously, that is the first thing people thought of when the OP said he wanted to build a nuclear reactor. I would discourage anyone from doing what the “nuclear Boy Scout” did.

A fusor, however, IS a reactor. If energy balance is the only reason a person can come up with to disqualify it as a nuclear reactor then you have also disqualified all the experimental fusion reactors ever built to date. Apparently, a reactor only "deserves" to be called one if real live Physicists work on it, spending billions of dollars building a big giant energy sink. It would be silly to expect a desktop device to produce net energy, and it is completely irrelevant to the discussion. Nobody ever said they wanted to produce net energy or that a fusor does.

The list I mentioned wasn't exhaustive... but those people BUILT the device that produced nuclear fusion. They didn't just turn on a device that someone else built.

Just because you don't know somebody isn't a reason to say that it is impossible or absurd to build a reactor, when in fact it is not (the fusor being the only example I know of). Many people have done it safely with very little money (a few thousand dollars) and if someone has their heart set on it they can do it. Warn them of the dangers, sure; say there are better projects, fine; but don't sit around and discourage people from doing things that you have never done yourself just because you think it is dangerous. IMO there are far too many people on the internet whose only response to inquisitive minds is "YOU"LL KILL YOURSELF!"

-Alan
 
  • #28
Your school should buy one of these!

Here's a nice garage-size reactor. One-man operation, and it runs on regular house current!

http://coldwar-c4i.net/EW-1957-01-28/059.html"

Albert LaFrance
 
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  • #29
real cool when the doe turns your house into a superfund site! :rolleyes:
 
  • #30
alancj said:
A fusor, however, IS a reactor.

NO - a fusor is NOT a reactor!

If energy balance is the only reason a person can come up with to disqualify it as a nuclear reactor then you have also disqualified all the experimental fusion reactors ever built to date.

Actually, I don't consider the experimental magnetic fusion devices "reactors" either.

Apparently, a reactor only "deserves" to be called one if real live Physicists work on it, spending billions of dollars building a big giant energy sink. It would be silly to expect a desktop device to produce net energy, and it is completely irrelevant to the discussion. Nobody ever said they wanted to produce net energy or that a fusor does.

I don't expect a desktop device to fly and transport people either - but that doesn't
mean that it is OK to call some desktop device an "airliner".

I don't expect a fusor to produce net energy - so I don't expect to be able to call
it a "reactor" - something it definitely is NOT.

The list I mentioned wasn't exhaustive... but those people BUILT the device that produced nuclear fusion. They didn't just turn on a device that someone else built.

That's also what I'm talking about - people building things. You don't learn much in
a nuclear lab just by turning on a device.

Just because you don't know somebody isn't a reason to say that it is impossible or absurd to build a reactor, when in fact it is not (the fusor being the only example I know of). Many people have done it safely with very little money (a few thousand dollars) and if someone has their heart set on it they can do it.

Don't you understand - it is IRRESPONSIBLE for a professional in a field that could hold
dangers to suggest to someone that they don't know and don't supervise to encourage
them to undertake a project that has inherent dangers such as radiation and high voltage.

and discourage people from doing things that you have never done yourself just because you think it is dangerous.

Just you hold it right there Alan! You don't know me - you don't know what I have done.
Don't cop this attitude that I'm saying this because I can't do it! For your information,
I'm part of the only design teams that have gotten NET thermonuclear energy production.
I've designed experiments MUCH more complex than a fusor.

So where do you get the AUDACITY and UNMITiGATED GALL to suggest that it's
because I haven't done something myself?

IMO there are far too many people on the internet whose only response to inquisitive minds is "YOU"LL KILL YOURSELF!"

The Internet is NOT the place for a young student to get advice and guidance on this
matter. In case you don't know; there's no QUALITY CONTROL on the Internet.

A student that is interested in this type of project needs to check out their local laws,
and get the guidance of a TEACHER! If a local high school teacher isn't qualified; then
perhaps a professor at a University - but for Heaven's sake NOT the Internet

I would expect that a student that has the capability to undertake such a project; would
also have the ambition to research this in the library, with local officials, with teachers,
with professionals in the area that can give them the type of guidance that is required.

Unfortunately there ARE too many cases of young scientists injuring themselves because
they didn't have the proper supervision.

As a professional, as an employee of the University of California; I'm bound by certain
ethics, and moral codes that you are evidently unaware of.

Suppose I encourage somebody, and they injure themselves. They could file a lawsuit
against the University of California, saying "Your employee who is a professional
physicist encouraged this young impressionable student to undertake this dangerous
project [ a project he knew to be dangerous because he is a professional ] and he had
no way of supervising the potentially dangerous activities of this young student".

Therefore, I am FORBIDDEN from this type of encouragement!
If you don't like it - take it up with the LAWYERS! However, the legal matters
are secondary - what is REALLY important is this student's SAFETY.
Although this type of project can certainly be done safely; I can't encourage it
unless I know the student has the proper support to carry it off safely.

However, until this young student has the degree of "hands-on" supervision that is
required for a project dealing with radiation and high-voltage; I would have to discourage
them from undertaking such a project unless it can be done PROPERLY with the
right supervision.

Dr. Gregory Greenman
Physicist
 
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  • #31
Albert LaFrance said:
Here's a nice garage-size reactor. One-man operation, and it runs on regular house current!

http://coldwar-c4i.net/EW-1957-01-28/059.html"
That was 1957. Such a device would not be permitted in a high school, and only in a univeristy with a license, and that program would be audited for compliance with NRC rules and regulations.

When I was in grad school, we had to do a detailed review (accounting) of all radioactive sources and nuclear material. Operators of the training reactor were certified and re-certified, and that was reviewed by the NRC.

There are very strict rules with respect to the production and use (legally that is) of devices that produce nuclear reactions. I have to wonder of those people who have reported building fusors have complied with all pertinent laws.

Also, one can build a plane or car, but planes have to be tested and certified by FAA, and cars have to be street legal to take on the road. Nuclear systems are much more stringently regulated.
 
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  • #32
Albert LaFrance said:
Here's a nice garage-size reactor. One-man operation, and it runs on regular house current!

http://coldwar-c4i.net/EW-1957-01-28/059.html"
Albert,

In order to legally own and operate such a device; the owner / operator would need a
Class 104 operating license from the Nuclear Regulatory Commission:

http://www.nrc.gov/reading-rm/doc-collections/cfr/part050/part050-0021.html

Dr. Gregory Greenman
Physicist
 
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  • #33
Morbius said:
NO - a fusor is NOT a reactor!

"That word, I do not think it means what you think it means." - Fezzig, the Princess Bride

In general a reactor is an isolation vessel in which a controlled contained reaction takes place. Based on that notion, a functional fusor qualifies as a reactor. Moreover, fusion reactions take place in a running fusor, so it qualifies as a fusion reactor.

I'm guessing that when you write 'reactor' you're thinking of something more specific and technical - perhaps involving self-sustaining reactions.
 
  • #34
NateTG said:
I'm guessing that when you write 'reactor' you're thinking of something more specific and technical - perhaps involving self-sustaining reactions.
Nate,

In the 'nuclear" field - a "reactor" is self-sustaining.

Yes - in I know that in the field of chemical engineering a reactor is a vessel for
isolating and conducting chemical reactions on a large scale.

Just because there are nuclear reactions going on in the fusor is NOT enough to call
it a reactor. You can have nuclear fusion reactions in little tubes that look like vacuum
tubes that give you a pulse of neutrons when high voltage is applied. I don't call them
"reactors". They are NOT reactors - and NEITHER is a "fusor".

It confusing to people who hear about "fusors" referred to as reactors - it gives them the
impression that it is an energy source via nuclear fusion. It isn't - it's a dead end.

I've gotten questions like this from friends and neighbors that read this and ask,
"Why are you spending all this money for a big facility like the National Ignition
Facility; when a teenager can do the same thing in his garage?"

The point is - the teenager CAN'T do the same thing in his garage. The "fusor" will
NOT reach thermonuclear ignition. A facility like NIF is required for that. So to
keep the public well informed - let's NOT give them the impression that the "fusor"
is anything but a "toy".

Dr. Gregory Greenman
Physicist
 
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  • #35
I don't know if this has been stated before. Check the rules. Some don't allow certain temperatures to be attained. I remember reading about a high school student doing this. His name was Brian something I believe. Google Brian nuclear reactor and I'm willing to bet you'll get his page.
 
  • #36
moose said:
I don't know if this has been stated before. Check the rules. Some don't allow certain temperatures to be attained. I remember reading about a high school student doing this. His name was Brian something I believe. Google Brian nuclear reactor and I'm willing to bet you'll get his page.
Moose,

I believe one of the issues is the radiation field. One can get a fairly high radiation field
without a high temperature. After all, the little electron accellerator that produces X-rays
for your dentist doesn't get very hot.

There have been many students that have undertaken projects like this - without the proper
supervision, and without knowing what they are doing; and have created problems for
themselves and others.

I don't think building something like a "fusor" is especially worthy in the type of training
one would hope a student would get from a science project. If all the student does is get
the plans for some apparatus off the Internet, and builds it; I don't think that is particularly
instructive.

The purpose of a science project, in my view; is to give the student a chance to
"problem solve". That's the key skill that they need to practice and become adept at
for a career in science.

I would much more like to see the student try to build something of their own design.
That way, they'll bump into all the problems that one does when designing something
new - and the student will have to figure out the solution to those problems.

I believe that's infinitely more rewarding and valuable an experience for the student than
putting together some device that someone else has already designed. When one merely
puts together an apparatus that someone else has designed, the student doesn't really
get an appreciation for why the device was designed the way it was, as opposed to some
other way. Yes - I do realize that the student may make modifications to the given
design - but nothing beats designing something from a clean sheet of paper.

Reminds me of the old adage: "The person that knows HOW to do something will always
have a job - working FOR the person that knows WHY!"

Dr. Gregory Greenman
Physicist
 
  • #37
alancj said:
What about a fusor? Those can produce neutrons and plenty of x-rays and I don't think they are illiegal...

The construction of a farnsworth fusor wouldn't be absurd and can achieve nuclear fusion (even better than fission!). A hand full of amateurs have successfully built working (fusing) fusors in this country, including some very young people (well, not 6 year-olds). This would be an ambitious, but doable project IMHO.

You could also built a fusor demonstrator, a far less dangerous and costly version of the real thing, that would none-the-less show the principles behind electrostatic confinement. Basically you need a vacuum chamber and vacuum pump, a high voltage power supply, some stainless steel wire to make your anode and cathodes, and the knowledge to put it together.

What do the rest of you think?

-Alan

Yep.

See:

http://www2.ljworld.com/news/2006/nov/19/teen_creates_nuclear_fusion_basement/

http://www.fusor.net
 
  • #38
Morbius said:
Nate,

In the 'nuclear" field - a "reactor" is self-sustaining.

(...)

Dr. Gregory Greenman
Physicist

Morbius,

I'm only a dull engineer but by your definition, all the tokamaks, ICF facilities, etc., built up to date aren't reactors, as they are not self-sustaining. And then the R on ITER should not be granted until it demonstrates that could do break-even AND extracts enough energy to sustain itself without external power inputs. I find this kind of disturbing.

Best regards.

Jose
 
  • #39
sunday said:
I'm only a dull engineer but by your definition, all the tokamaks, ICF facilities, etc., built up to date aren't reactors, as they are not self-sustaining. And then the R on ITER should not be granted until it demonstrates that could do break-even AND extracts enough energy to sustain itself without external power inputs. I find this kind of disturbing.
Jose,

I don't consider the tokamaks, ICF facilities to be "reactors".

They are "experiments" - in spite of what the builders of these devices call them.

If someone today says, "nuclear reactor" - then it's clear that the meaning is that
the device is a "nuclear fission reactor".

In the future, when we have power plants based on fusion energy, then the term
"nuclear reactor" will become ambiguous - there will be the need to qualify whether
the device is based on fission or fusion.

However, until that day, "nuclear reactor" means a "self-sustaining, critical, nuclear
fission reactor" in my parlance, and that of most scientists.

Dr. Gregory Greenman
Physicist
 
  • #40
Dr. Greenman,

Thanks for the clarification.

Jose
 
  • #41
Morbius said:
- it gives them the
impression that it is an energy source via nuclear fusion. It isn't - it's a dead end.

I've gotten questions like this from friends and neighbors that read this and ask,
"Why are you spending all this money for a big facility like the National Ignition
Facility; when a teenager can do the same thing in his garage?"

The point is - the teenager CAN'T do the same thing in his garage. The "fusor" will
NOT reach thermonuclear ignition.

Morbius -
Sorry to come in late on this. I'm familiar w/ the various criticisms (Rider, Nevins) of IEC fusion approaches that stand demand answers from anyone proceeding down that road, but I don't consider those criticisms proof that all IEC is a 'dead end'. What do you have in mind when making that statement? If its purely a manner of daunting engineering practicalities, then one might say the same about huge neutron flux producing Tokamaks. Lidsky certainly did.

mheslep
 
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  • #42
mheslep said:
What do you have in mind when making that statement? If its purely a manner of daunting engineering practicalities, then one might say the same about huge neutron flux producing Tokamaks. Lidsky certainly did.
mheslep,

I'm just saying that no-body sees a way that IEC is ever going to lead to a self-sustaining
reaction and net power production.

We can induce fusion by accelerating deuterons in a cyclotron and throwing them at a
target. You get fusion - but there's no way that such a configuration is going to give you
fusion "ignition". IEC is in this same boat.

Contrast this with a technology like inertial confinement fusion, or "laser fusion". It is
believed that we CAN get fusion ignition in such a configuration - as long as the imploded
pellet can trap the alphas produced in the reaction. That means we have to implode a
big enough pellet; but havent't had the laser energy to do it.

That has changed with the building of the megajoule-class lasers of the National Ignition
Facility, or NIF. The reason it is called NIF, is that it is expected to achieve "ignition":

http://www.llnl.gov/nif/

Dr. Gregory Greenman
Physicist
 
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  • #43
Morbius said:
...I'm just saying that no-body sees a way that IEC is ever going to lead to a self-sustaining reaction and net power production.

We can induce fusion by accelerating deuterons in a cyclotron and throwing them at a target. You get fusion - but there's no way that such a configuration is going to give you fusion "ignition". IEC is in this same boat.

I'm not so sure. First people working on IEC for energy purposes don't fire at solid targets, they are instead beam-beam focus designs and they are well aware of maxwellian 'collisions' hurdles thanks to Rider et al. There some renewed effort to address them, c.f. http://forum.nasaspaceflight.com/forums/get-attachment.asp?attachmentid=25188" 2003

Contrast this with a technology like inertial confinement fusion, or "laser fusion". It is believed that we CAN get fusion ignition in such a configuration - as long as the imploded pellet can trap the alphas produced in the reaction. That means we have to implode a big enough pellet; but haven't had the laser energy to do it.

That has changed with the building of the megajoule-class lasers of the National IgnitionFacility, or NIF. The reason it is called NIF, is that it is expected to achieve "ignition"
As I understand the issues w/ implosion, the technical ability the build higher power lasers was never in question. Issues that are in question:
-Drive efficiency of the laser: high enough to ever enable net power?
-Symmetry of energy delivery. Yes there have been order of magnitude improvements here but I'm unaware that anyone has demonstrated the physics & engineering necessary for net power.
-Protection of the illumination devices. How does one have a clear illumination path to the fusion target and at the same time protect it from GW neutron fluxes?

mheslep
 
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  • #44
mheslep said:
-Symmetry of energy delivery. Yes there have been order of magnitude improvements here but I'm unaware that anyone has demonstrated the physics & engineering necessary for net power.
mheslep,

The only devices that produce net energy productions from fusion work quite well in that
regard; the symmetry of energy delivery is pretty much solved.

Dr. Gregory Greenman
Physicist
 
  • #45
Morbius said:
the symmetry of energy delivery is pretty much solved.

Oh? Is that via direct or indirect drive, or both? Could you suggest any references?
 
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  • #46
mheslep said:
Oh? Is that via direct or indirect drive, or both? Could you suggest any references?
mheslep,

Most of the designs I've seen are for indirect drive.

http://www.llnl.gov/str/Haan.html

For the present, Livermore target designers are focusing on both the indirect-drive
capsules and the hohlraums enclosing them.

http://www.llnl.gov/str/September02/September50th.html

http://www.llnl.gov/str/JulAug05/VanArsdall.html

http://www.llnl.gov/str/September05/Hill.html

Dr. Gregory Greenman
Physicist
 
  • #47
amberb617 --do you happen to live in Iran?
 
  • #48
I am reminded of the time it got into the newpapers that a boy in New York City had built an atomic bomb as a high school project! It even was made into an episode of the "Barney Miller"- with the bomb being brought into the police station and everyone being terrified of it.

The boy had indeed built an atomic bomb- he just didn't have any fissionable material for it...
 
  • #49
HallsofIvy said:
The boy had indeed built an atomic bomb- he just didn't have any fissionable material for it...
Nor high explosives.
 
  • #50
HallsofIvy said:
The boy had indeed built an atomic bomb- he just didn't have any fissionable material for it...
HallsofIvy,

No boy has built an atomic bomb!

The design of an atomic bomb took some of the brightest physicists of the world several
years to design - Oppenheimer, Bethe, Teller, Fermi, Von Neuman, Feynmann, ...

You aren't going to tell me that a little kid in New York did what Nobel Prize caliber physicists
took years to do! It still takes whole teams of scientists the better part of a year or more
to design nuclear weapons; even using the world's most powerful computers and
software that has been honed for decades.

Add to that the boy had neither the fissile material [ not fissionable - U-235 is "fissile"
U-238 is "fissionable" which means fission is a threshold reaction; but you can't build
a bomb out of U-238 ], and neither did the boy have chemical explosives.

It makes a "cute" story to think that a high schooler could build a nuclear weapon;
but it's pure fantasy!

Dr. Gregory Greenman
Physicist
 
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