I stumbled across this web site some time ago and all that vacuum must
have sucked me in Now I want to build one too.
The ultimate goal in the fusion business is to break even or better
generate a surplus of energy. So has anyone published a rank list ?
I would like to see a list of all Fusioneers and their machine efficiencies in
descending order.
That way one would get a bit of a competition going for the 1st. place,
which will inevitably push the boundaries. Much the same way as the
electronics industry compete for the fastest processor.
One would have to define a set way to measure the output power over
input power.
Not to give you a short answer, but read up in these threads here about "efficiency" .
Approximately 1 million neutron events per second is the high end of the amateur range to date...at 2.45 MeV per event and throwing in a proton event of similar energy... you get 2 x10^6 x 2.45x10^6x 1.6x10^-19 joules/sec or watts.
That's 0.8 micro watts output for a system absorbing 10's of mA at 10's of kV input energy, plus pump power and etc.
You can do the math... micro watts out for hundreds to kilo-watts input. Efficiency of about 0.000000X %!!
It won't light your house or mine... just yet.
Read and learn....lots of really good stuff here... it will definitely set the picture in focus.
I agree, it is a feeble amount of energy, however I am a little bit more
optimistic.
A potential power generating Fusor's main purpose would be to generate
heat. I imagine the whole apparatus would be enclosed in a water tank of
some description, so much of the input energy need not be lost, it simply
goes into heat and X-rays, and could be recovered along with the fusion
energy.
A quick mental calculation puts the power consumption of an amateur
Fusor at 150 - 200 watts, and using existing technology one might recover
95% of that energy, making the net consumption 7.5 - 10 watts.
Sure the gap is still huge, around 10^-8 to 1 .
My point is that we need to work the problem from both ends, increase the
reaction rate and recover the heat loss.
Borated water in a 3 foot jacket around a fusor would certainly trap 99.9% of the energy output from a fusor and heat the water. Unfortunately, you can't really expect that energy in the hot water to do anything efficiently due to conversion and conduction losses which even in the best processes can be 10%-20% - hot water to electricity.
It is a loss upon loss process.
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
The main point about the futility of heat recovery at this stage of things, is that we are taking electricity, already made from heat, at about 30% wall plug efficiency and making more heat from it along with about .01 ppm fusion energy.
There is no point whatsoever being concerned about recovering the heat in a fusor. Rather, we should be looking for ways to minimize it, as it mostly represents a low energy, (as in few eV) gas discharge energy, without reducing the number of fusion reactions per second. Doing that WILL increase our efficiency, although not by much on an absolute scale, it could by upwards of 10x, though, in a relative sense.
There have been many attempts thus far and much ingenious thought aired by the group here, but as yet we are still not able to do much along this front. It is not a trivial problem.
Yes, indeed they will conquer this issue for sure, just like all such issues are handled. Will they solve it before we have a space hyper drive and teleportation systems in homes is the real question. Thermodynamics is a pretty limiting thing.... in a law of physics kind of way.
Fusion will need to attain full sustatined ignition and not just breakeven or over unity operation before the power companies will get all goose pimply over it and ask it out to the prom.
Fission is inhand now and crankin' out gigawatts, world wide, every day...... NOW.
Still, we dabble, dawdle and bumble along with fusion, not because it is clean or safe, (niether of which it is), nor, because we can see any light at the end of the tunnel, but because its pursuit gives money to feed and clothe the many thousands of families whose bread winner is in need of work.
I don't wonder a bit why we are not much closer to the fusion gold post than in 1952. I am reminded of the comedian who once said " I used to be a buffulo hunter, mule skinner, and an indian scout..............We killed all the buffalo, got rid of the mules and run off all the indians................I guess you could say I worked myself out of a job."
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Good question............All have been answered in many past posts with the math clearly handled.
Assuming you really evacuate to 10e-6 torr and back fill to a realistic fusion pressure of 10E-2 torr with D2 then you have approx 10E14 molecules of D2/cc in a liter chamber that would be 10e17 D2 molecules in the chamber. Again roughly.
Thus you might expect about only 10e10 reactions before you are not really doing DD fusion any more. The problem is you would be doing a better reaction of TD fusion well before this situation occured.
Given that I am playing a bit fast and loose with the figures, 10 e 10 fusions in DD alone would produce ~4 mev per event or 4X10e16ev of energy. or ~6.5 X10e-3 joules or about 6.5 milliwatts per 10 billion fusions. As most fusors fuse at less than 200,000 fusions/second that would make an operating session of 50,000 seconds or about 14 hours.
None of the above is possible in reality, of course. You couldn't work well in a sealed off fusor, and by current standards you would expend about 2800 watts to get .006 watts of fusion energy out. Again, you couldn't do even this good in ideal situations.
You see that the vapour thin fuel supply is not capable of much real output even when a tens of billions of fusions occur.
To put a real cap on it all, at 10ma current in a real fusor, we tend to accelerate about 10e16 (10 quadrillion) ions/second!!!! In this time only about 100,000 might fuse. A 10e11th Loss factor.
Never fear, the folks spending our billions on fusion haven't done too much better.
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
"In 1997 JET achieved a peak fusion power of 16 MW, which as of
2004 is the world record. The same experiment achieved a value of
Q=~0.7 where Q is the ratio of fusion power to input power. (A self-
sustaining nuclear fusion reaction would need a Q>1)." http://en.wikipedia.org/wiki/Joint_European_Torus
I have heard that JT-60 has hit Q: 1 to 1.25 but I can't find a reliable
source for that.
PS: Q is thermal efficiency. At Q ~= 5 – 20+ such a plant would be
able to produce useful amounts of power but this is a tiny increase
over the Q 0.0000001 (+/- a few 0’s) type results such machines
where at 50 years ago.
That figure is very interesting. Do you have any information on how long the device was able to produce fusion power at that level?
Producing a single 2.45 MEV neutron in a sub psec interval is about 1 Watt, as a simple "power" calculation. Of course it wouldn't amount to much, unless there was a steady stream, say ~ 10^12 or so per second. Then things would get really interesting.
Thanks Richard, for putting some rough numbers down and confirming
what I already suspected, that not enough energy can be produced with
the fuel in a Fusor to really make any use of it.
Dave smells the classic "fusion - real soon now" rat here and probably just forgot that these bastards lie like a rug to get the bucks.
Dave also realizes that these bastards go for milliseconds to seconds and then sadly are quenched when ablation and shattered crap from tiles fills and spoils the reaction vessel. As few DAYS later they are ready for another 0.5 second failure shot.
Do they SUM all power used? Not they! They consider the power in to be only the wattage fed into the plasma!!!! They avoid the near megawatt drains of all the auxilliary support gear and electromagnets, etc. Their lie is one of both omission and commission, for technically, they can't be brought to the mat by an ignorant public. Ostensibly it is a scientific lie, and falsehood when viewed by any good scientist or even bean counter.
It is obvious..........They LIE.
I would be personally stunned to learn they have an all up, bottom line Q of 0.5%
Regardless, even at a Q of 2.0 it would never go on line for power use as a fission plant of 100 megawatts would be needed to power a 200 megawatt fusion reactor. Give me a large personal break!
It is really a matter of self sustaining ignition or walk off the field.
A Q of 5.0 is not ignition and still a definite NO GO for power use.
Phoeey on JET and Phoeey on ITER. Local fusion jokes played on you and me at our expense.
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
You are correct in that they operate for short time frames, but they are
also dealing with an extreme power source ITER is going to be a
500,000,000w neutron source. That will quickly transform many safe
every day materials into a long-term radiation hazard. So they are
focusing more on increasing the system efficiency before getting into
stability issues, as it’s hard to experiment in a highly radioactive
environment. So first they are focusing on increasing the systems
efficiency before destroying their ability to modify the system.
In your own test environment’s you do the same thing. Rather than
using stable power levels, which operate for days, or even months at
a time you boost the power levels creating an unstable condition and
see what happens.
Going from Q = .0.000001 to Q = .1 is probably a lot more difficult
than going from Q = .1 to Q = 100. As (.1 / 000001 = 100000) > (20/
.1 = 200)
In the same way going from .0001 seconds to 2 seconds is harder
than going from 2 seconds to 5 hours. When they operate at high
power levels they create an increasable unstable system but by
sacrificing some efficiency they can create a much more stable
device. Anyway if you look at confinement times and efficiency
levels both of these have gotten much better over the last 40 years.
You have to stop looking at things as all numbers less than a second
are about the same as a second and recognize that there is a larger
relative difference between 10^-1 seconds and 10^-5 seconds than
there is between 1 month and 10 years.
“They avoid the near megawatt drains of all the auxiliary support gear
and electromagnets, etc.” It’s true that they only include power levels
while operating the device but that’s reasonable as the energy
needed to charge up those huge magnetic fields and cool the coils
down to operating temperatures is nearly constant if they operate for
1 second or 1000 seconds so to keep people from making such
unimportant numbers alter the all important Q they ignore them.
However there is also a good reason to ignore the energy cost for
operating all that support gear, 10 megawatt’s for such systems is still
insignificant when dealing with a 500MW system, ok they are
skipping over 2% of their power costs big fucking deal however it’s
much more important at 5MW which is going to distort the relative
efficiency of the systems. They could include things like the cost to
keep the coils cold, but some cheep insulation goes a long way to
dropping that cost down so it’s probably a minor issue when
considering how to design a test environment. EX: It’s probably
cheaper to have easy access to internal components than it would be
to add a lot of bulkily insulation.
So yes, they assume they are going to need to build a more stable
system at some point, but they are more interested in increasing
operating efficiency until the system crosses “ignition” than they are
in keeping the system running for days. (It’s also cheaper to have a
500MW power drain that is off most of the time than it is to try and
operate it 24/7).
PS: Many power plants operate at ~40% thermal efficiency. So at Q
= 5 x energy * .4 efficiency ~= 2x the input energy. Now as long as
their operating costs are less than the value of the of the extra energy
they are creating it could be reasonable to build and operate such a
plant. EX: Fuel costs are only 5% of the operating cost of a nuclear
power plant. So it might be reasonable to expect that they could
operate significantly more cheaply than a coal power plant that
consists of many of the same systems. But, the real cost of such
plants are much more complex than simple fuel issues.
Part of the problem here Richard is that it is fairly easy for scientists to
convince ignorant polititians that a project is worth starting and once it is
started, to keep it running.
Embarrassment to admit that the darn thing didn't work, kids at school,
mortgage payments, affairs with the lab assistants etc. are all motivators
to keep going.
I am always ready for this thing to wrap up and have them show me, but alas, the claims and supposed successes inchworm forward amid much hype and fanfare with billions in the money spent and billions more to be committed.
Walls ablating, activation products a plenty, days between 1 second shots, all add up to just about being no where when it comes to getting useful energy over the wires to the home outlets.
It all boils down to man not being a good creator. We are used to destroying stuff; releasing pent up potential energies. We are not used to creating them and then looking for excess. Fusion makes energy with massive input energies required.
This effort is real close to the stock perpetual motion, over unity, machine which science would normally poo-poo. They can show it isn't such a device only becasue the thing ostensibly needs fuel to make it go. Outside of their being unable to make it go at all, it is a great idea whose time is still far off, but,.... real soon now and with hundreds of more billions, that distant horizon can be drawn much closer........we think.....we hope.
I view all of this with a typically jaundiced eye; much as I would a perpertual motion machine freak with magnets on a wheel saying; "real soon now....If I only had stronger magnets, this baby would really take off....take my word for it....You'll see."
How much can a horse be beat until it drops?
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
"The fusion energy produced in individual magnetic confinement
fusion experiments has risen by a factor of more than one trillion
since 1970" www.er.doe.gov/Sub/Organization/ program_offices/Fusionflier.pdf
and
The power input is probably also up by a factor of a trillion as well. Near stasis??.... Bigger is not necessarily better.
True, scientific and functional ignition means the reactor will run on its own produicng useful net power with zero input energy from any other outside source other than its own output being feed back to it for a reasonable and useful period, once started.
This has never ever been done by any fusion device in the history of the planet.
They may have had a fusion-like event that some hopefuls present felt was ignition-like in the most theoretical sense of the word.
I would love to get a second opinion regarding the value of JET's performance and possibilities from someone in the power distribution engineering office of a functioning power utility.
Remember the old caveat.... "your performance may vary from the figures stated".
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
I think I read all of the posts in this thread and feel this post should be parented by many of them, so I’m posting it at this level.
There have been discussions of Qs achieved and the improbability that Inertial Electrostatic Confinement can ever achieve “real “ breakeven due to all of the losses involved in changing the resultant energy back into electricity. I have two questions:
1) What is the theoretical maximum Q utilizing Inertial Electrostatic Confinement? Not in electricity output based on electricity input, but heat output based on the “effective” heat input (replace energy for heat if your so inclined.)
2) Assuming all technical hurtles can be overcome, and a Q value (as determined in 1 above) of 2 or better, couldn’t this technique be beneficial in heating applications. For comparison, current heat pump techniques result in about 300% efficiency (a Q of 2) at moderate temperature differentials.
The theoretical Q is through the roof for a full fusion burn via ignition. Q=1,000,000,000,000 or more.
The Q with no burn or ignition is unknown.....There is no theory on this one. Thus far, at the current IEC plod along, we put the max Q ACHIEVED at about 1.0000001.
This would be realized "space heater" Q of ten million BTU in and 10 million and one BTU out. One BTU of fusion related heat for 10 million BTU of non fusion input heat.
One would hope that a Q of 1.5 would be attainable but by what method?
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
What is keeping an upper limit from being determined? From my novice stance, an upper limit (which may be way to high) is calculable from the required collision velocity to cause fusion (assuming a perfect head on collision and alignment, no interface from other atoms…) and the energy released as a result of the fusion. I’ve noticed in many places that the energy released, as a result of fusion, is known for many atoms. I have not found fusion velocities for those atoms nor a statement of the energy required to obtain those velocities.
The upper limit to fusion would be related to the density of fuel you could hold in the reaction and its max temp. I do not know where nature's limits occur as there are certainly places in space or super novae or neutron stars or whatever, where normal stellar fusion looks pretty darned shabby.
Q's are related to a bulk studied reaction or overall process where energy is input and energy is output.
The Sun could easily be working at a Q of .003 or 1.003. Who knows?! There is no way to quantify the gravitational energy of the entire energy system we call the sun. Where is the core? how big is it? What is its mass? Where is fusion done?...The mantle? The core? A thin zone? Everywhere within the volume?
Too many unknowns.
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
The problem is there is no energy that will produce fusion in 1 hit. That hit, which is by far more likely to fail (scatter) than succeed (fuse) then disributes the input energy between the two particles, making the total probability for fusion lower. Virtually all high energy deuterons fizzle out by scattering and thermalise. Its thus impossible to get a Q significantly above 1 by just flicking deuterons into a target.
The suns Q is very high, probably infinite. This isnt an 'impressive' Q, its just a result of applying a measure that is only valid for dynamically confined systems. While the amount of energy required to form the gravitational well is large its essentially a passive confiment system, you dont have to add external energy in order to maintain the reaction. Fusion balences itself so that the rate is equal, or almost equal, to that required to prevent collapse.
Alan, it appears from the experiments carried out so far, that you have to
expend a lot of energy in order to fuse Deuterium, and that there ought to
be a limit to how much energy you can get out for a given amount of input
energy.
I personally do not believe this to be the case, I believe that we can make
a fusion process that will run by itself, after it has been started.
After all that would not violate any known laws of physics.
To say the sun has no seed energy is a sad mistake. No fusion could possibly occur anywhere in the universe were it not for gravity. This is potential energy contained in all matter and is stored there ready for use. The dynamic energy FROM the sun comes directly from fusion and fusion WITHIN the sun comes solely from garvitational PE exchange. Yes, the sun is in stasis (balance between fusion's outward pressure and gravity's crushing inward pressure).
The first heat generated in any star is kinematic and due solely to gravity as it acretes. The first electron released in this heating acretion process is brought out of its locked, coulombic, hydrogen atom orbit due solely to gravity and the first fusion is, likewise, due solely to gravity. The gravitational energy of any acreted star never ceases to be nor will fusion stop until it goes nova, or super nova, scattering its fuel supply and its bounty of fused atoms out into the universe.
To dismiss gravity or its continuous energy transfer to a star and thus, the fusion process there, as some casual stasis system would be ridiculous. Gravity works forever, just like coulombic PE reactions, makes all light and all magnetism. Thus, all EM radiation and all matter fusions are side reactional WASTE PRODUCTS of gravitational and coulombic exchanges. These waste products are themselves valuable and represent stored energy, i.e., if the waste matter is of a higher Z than iron or when the light, (electromagnetic radiation), carries energy into space to re-animate and redirect interstellar atoms (stirring the mix).
Gravity plays nuclear fusion and unlocks coulombic bonds while coulombic reactions plays complex, dead matter, assembly chemistry and resists casual fusion. Continual assembly, disassembly and stiring all caused by only two forces in constant exchange via the medium of matter which contains both forces and are inseperable from it.
So, the Q of the sun could be .0000001 if one looks at the potential seed energylocked into the FOREVER gravity there needed to both start and continuously drive it versus output.....OR.... Q= 1.0000000 if one looks at the balance or stasis condition being the sole arbiter. Or one might view the Q as being nearly infinite if one looks at the stasis process as no net energy contribution for a 20 billion year fusion output. There is obviously no correct single answer. The simple truth is fusion is enevitable solely due to the continuos exchange of gravitational energy of the mass of the star being locked down through conversion into nuclear forces which are non-extant until they are themselves created at the moment of fusion.
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Now I want to build one too.