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View Full Version : Stars are giant fusion plants?



Inclusa
2011-Apr-02, 04:11 AM
I cannot say for sure; but that's what I heard.

Hungry4info
2011-Apr-02, 04:49 AM
You could make a case that stars are indeed supermassive gas giants that have begun fusing.
But stars and gas giant planets (probably) form in different mechanisms.

Jamotron
2011-Apr-02, 04:56 AM
You could make a case that stars are indeed supermassive gas giants that have begun fusing.
But stars and gas giant planets (probably) form in different mechanisms.

Hehe, they mentioned "plants" , not "planets".

Inclusa
2011-Apr-02, 05:45 AM
Thank you! This is not a typo; I really mean "fusion plants".

Shaula
2011-Apr-02, 05:50 AM
Star shine due to fusion - that is very well established. They use gravity to confine the plasma, not magnetic fields, and fuse hydrogen, not deuterium or tritium (primarily) but they run off the same basic principles as a fusion plant.

Strange
2011-Apr-02, 10:07 AM
Except, of course, they do run, which fusion plants don't. Yet. Just another 50 years...

Trakar
2011-Apr-02, 05:35 PM
Except, of course, they do run, which fusion plants don't. Yet. Just another 50 years...

Well, since the 50s commercial fusion power plants have constantly and consistently been 20 years away, if they are now 50 years away, this may be a battle we need to stop fighting.

loglo
2011-Apr-02, 05:48 PM
Well, since the 50s commercial fusion power plants have constantly and consistently been 20 years away, if they are now 50 years away, this may be a battle we need to stop fighting.

We should know in 20 years if we will have it in 50 years. :)

Hungry4info
2011-Apr-02, 09:43 PM
Hehe, they mentioned "plants" , not "planets".

D'oh! Thanks. I read either and my brain thinks "planets," and I frequently write out "planets" when trying to write "plants."

Inclusa
2011-Apr-03, 02:28 AM
D'oh! Thanks. I read either and my brain thinks "planets," and I frequently write out "planets" when trying to write "plants." l

What would you call a dandelion, than?

astromark
2011-Apr-04, 09:12 AM
The gravity of the mass takes care of the containment issue... Energy output exceeds containment or it fails as a star.
While here on earth we struggle with plasma containment fields which seem to run seconds not minutes...
Its a very expensive fail history...

baric
2011-Apr-04, 12:24 PM
Why spend billions trying to design and construct a fusion plant when nature has already given us one at a safe distance with a 4-billion year life cycle?

All we have left to do is build the power conduits.

Shaula
2011-Apr-04, 12:49 PM
Because so far it has proven too hard and too expensive to do so - and that whole 24hr cycle thing doesn't help. With fairly low efficiency conversion processes (or efficient but horrendously expensive ones), no easy way to store power and rubbish distribution systems smaller, local systems that are always on tend to win out. Whether they should or not is another matter.

baric
2011-Apr-04, 01:34 PM
Because so far it has proven too hard and too expensive to do so - and that whole 24hr cycle thing doesn't help. With fairly low efficiency conversion processes (or efficient but horrendously expensive ones), no easy way to store power and rubbish distribution systems smaller, local systems that are always on tend to win out. Whether they should or not is another matter.

Yes, but the one we have is already up and running and solar cells are already producing more energy worldwide than fusion plants.

It would be interesting to compare the amount of research funding that has gone into nuclear fusion power generation vs. solar cell technology.

ravens_cry
2011-Apr-04, 02:17 PM
If you want to be sneaky, you could say that solar power is fusion power, the same way that the generators turned steam driven turbines when heated by the nuclear reactor is nuclear power. If you want to be really, really, sneaky, you could say the same about fossil fuels.

baric
2011-Apr-04, 02:39 PM
If you want to be sneaky, you could say that solar power is fusion power, the same way that the generators turned steam driven turbines when heated by the nuclear reactor is nuclear power. If you want to be really, really, sneaky, you could say the same about fossil fuels.

I'm not that sneaky.

Solar power is directly emanating from that giant fusion power plant in the sky and is so bright that it's blinding. It's the exact opposite of sneaky!

Shaula
2011-Apr-04, 04:39 PM
It would be interesting to compare the amount of research funding that has gone into nuclear fusion power generation vs. solar cell technology.
No amount of research is going to make them work at night.

ravens_cry
2011-Apr-04, 04:54 PM
*gets on soup box*
Which is why I like algae oil. You can't make plastic or medicine out of electricity.
*gets off soup box*

baric
2011-Apr-04, 05:47 PM
No amount of research is going to make them work at night.

Which would be a real problem if the Earth stopped rotating!

Shaula
2011-Apr-04, 06:59 PM
Which would be a real problem if the Earth stopped rotating!
Not really. That was my previous point about store and distribute issues. This getting off topic but my point was that while there is definitely a good case to expand the use of solar power it is not going to be the sole answer as it has limitations, practical limitations, to how much it can contribute. Given the enormous losses and trouble we have with storing and distributing energy some form of relatively local always-on power source is going to be needed. Fusion is attractive as a sort of high-tech one-stop solution but given the problems we have had not something I'd put money on.

agingjb
2011-Apr-04, 07:15 PM
As you say, storage and distribution are problems that influence the choice of source. Is it worth adding the need for a good sink to the problems of handling energy?

IsaacKuo
2011-Apr-04, 07:31 PM
Which is why I like algae oil. You can't make plastic or medicine out of electricity.
Yes you can (http://en.wikipedia.org/wiki/Methanol_economy). Well, you also need water and carbon dioxide. But essentially water + CO2 + electricity gives you methanol, and methanol can be converted to ethylene and propylene, and then to plastic.

baric
2011-Apr-04, 11:22 PM
Not really. That was my previous point about store and distribute issues. This getting off topic but my point was that while there is definitely a good case to expand the use of solar power it is not going to be the sole answer as it has limitations, practical limitations, to how much it can contribute.

I agree with this, but does nuclear fusion have any theoretical downsides?

glappkaeft
2011-Apr-05, 12:23 AM
I agree with this, but does nuclear fusion have any theoretical downsides?

Well, making it work has been kind of a showstopper so far. If we get it working the largest downsides are that the reactor becomes slighly radioactive after sustained use due to neutron capture and that the capital costs of the plants in will probably be high (possibly higher than fusion).

slang
2011-Apr-05, 12:44 AM
What would you call a dandelion, than?

Lots of words that are not allowed on BAUT.. they just keep creeping up no matter how many you pull out, root 'n all.

ravens_cry
2011-Apr-05, 03:30 AM
Yes you can (http://en.wikipedia.org/wiki/Methanol_economy). Well, you also need water and carbon dioxide. But essentially water + CO2 + electricity gives you methanol, and methanol can be converted to ethylene and propylene, and then to plastic.
Heh, so you can,:think: Is it even less efficient then photosynthesis? I personally have never heard it considered as a means of storing the energy, while algae oil has been proposed and worked on by several companies.

Inclusa
2011-Apr-05, 03:49 AM
Now this is getting intriguing: Some suggest that utilizing the existing "giant fusion plant" is more practical, even though it still has considerable limitations; others suggest continuous exploration of fusion power; some talk of algae farming as an energy source.

ravens_cry
2011-Apr-05, 04:28 AM
More like an energy storage device. The plus side is, algae or electrosynthesis, we use the chemicals used to store the chemical energy in so many other ways besides energy storage. We are going to need to do anyway when we run out of gettable oil, it is a matter of when, not if.

Shaula
2011-Apr-05, 05:38 AM
I agree with this, but does nuclear fusion have any theoretical downsides?
As has been said - it is a pig to make work and the designs so far are temperamental as heck. If anything doesn't work as well as possible then you get things like iron atoms in the plasma (shut down and restart), etched walls (shut down and refurbish) etc etc. Maybe that is just the sign of a very immature design but I cannot help but worry that in practical terms it might simply be too difficult for current technology. That said I think that fusion research is not a huge expenditure and it is really pushes the limits of engineering and our understanding of nuclear physics. So I don't see it as a waste of effort. I see it more like the space program - something worth doing for the side benefits alone.

Trakar
2011-Apr-05, 07:15 AM
Well, making it work has been kind of a showstopper so far. If we get it working the largest downsides are that the reactor becomes slighly radioactive after sustained use due to neutron capture and that the capital costs of the plants in will probably be high (possibly higher than fusion).

Fusion reactors: Their challenge to materials scientists (1979) - http://fti.neep.wisc.edu/pdf/fdm277.pdf

Fusion materials science: overview of challenges and recent progress (tutorial) -
http://www.ms.ornl.gov/fusionreactor/pdf/selectedpubs/APS-DPP%20mat%20sci%20tutorial.pdf

Nuclear bremsstrahlung and its radiation effects in fusion reactors (gamma and x-ray considerations) - http://iopscience.iop.org/0741-3335/51/3/035003

As you say, not that any of this is indicative of "insurmountable," and this isn't even getting into the need to breed sufficient tritium to fuel the current pre-eminent systems, but rather, that it is inaccurate to think of fission as "dirty" and problematic and fusion as "clean" and without operational problems. It is better to think of them both as nuclear power, and both with a lot of risk and complexity which generally equates to high investment and low profit margins on the public sector side of the balance sheet. Nuclear power will be as abundant and safe as we demand it, and ensure it, to be. No more, no less.

IsaacKuo
2011-Apr-05, 02:30 PM
Heh, so you can,:think: Is it even less efficient then photosynthesis? I personally have never heard it considered as a means of storing the energy, while algae oil has been proposed and worked on by several companies.
It may be more efficient than biofuels, but solar power systems cost more than growing algae or crops. So, even if biofuels might require more area, they could still cost less. Maybe.

Of course, you might use other sources of electricity rather than solar.

baric
2011-Apr-05, 03:57 PM
It may be more efficient than biofuels, but solar power systems cost more than growing algae or crops.

Solar panels can function in places where algae and crops cannot grow.

The Sahara desert. In orbit. On the roof of my car.

Strange
2011-Apr-05, 05:33 PM
http://www.maniacworld.com/grass-car.jpg

Ara Pacis
2011-Apr-05, 08:26 PM
I'd also be worried about Fusion as a source of neutrinos. A Fusion power plant may be detected by aliens.

baric
2011-Apr-05, 09:13 PM
http://www.maniacworld.com/grass-car.jpg

omg haha. This is hilarious.

Would you install weed-whackers on it analogous to windshield wipers?

Ara Pacis
2011-Apr-05, 10:38 PM
http://www.maniacworld.com/grass-car.jpg

His hood ornament should be a golf tee.

Shaula
2011-Apr-06, 05:24 AM
I'd also be worried about Fusion as a source of neutrinos. A Fusion power plant may be detected by aliens.
I hope you missed a smiley there. Our civilisation is not exactly stealthy.

Jamotron
2011-Apr-06, 05:27 AM
I hope you missed a smiley there. Our civilisation is not exactly stealthy.
I was wondering the same thing. But they would have to be within about 70 or so light years from here and have pretty good antennae to pick us up.

Shaula
2011-Apr-06, 03:49 PM
And they would need a rather amazing antenna to pick up neutrinos given the weakness of their interaction with matter and the inconvenient fact that there are millions of much more powerful neutrino sources out there.

Ara Pacis
2011-Apr-06, 08:16 PM
Actually, I was partly serious. I've read that our radio signals aren't very detectable after a light-year or so. And neutrinos come in different flavors based on the process of emission, which might allow for discrimination by observers. We already have neutrino observatories.

Shaula
2011-Apr-06, 08:59 PM
Neutrinos also oscillate. So as they travel through space they become more mixed. Detecting even a planet's worth of nuclear plants (fission plants put them out too, you know!) would be a huge challenge given the background.

Ara Pacis
2011-Apr-07, 10:51 PM
Neutrinos also oscillate. So as they travel through space they become more mixed. Detecting even a planet's worth of nuclear plants (fission plants put them out too, you know!) would be a huge challenge given the background.

Yeah, but I wonder if enough information could be detectable with future detectors that they might be able to discern flavors, locations and on-off cycles that are non-stellar in nature.

Trakar
2011-Apr-08, 06:06 AM
Yeah, but I wonder if enough information could be detectable with future detectors that they might be able to discern flavors, locations and on-off cycles that are non-stellar in nature.

A galactic partyline, ...or trotline.

Noclevername
2011-Apr-09, 10:33 PM
http://www.maniacworld.com/grass-car.jpg

Ch-ch-ch-Chia Pet!

Shaula
2011-Apr-10, 06:36 AM
Yeah, but I wonder if enough information could be detectable with future detectors that they might be able to discern flavors, locations and on-off cycles that are non-stellar in nature.
Not flavours. As I said. Neutrino beams mix. You are postulating an incredible increase in what we think of as possible with these detectors. You may as well worry that future detectors of radio waves or light will get so good that these aliens will be able to see us from huge distances. Neutrino detection resolution is probably never going to be that good and on off cycles are confused by the fact that most reactors are always on and that would be loads on the Earth and they would not be synchronised. I really wouldn't worry about neutrinos. Unless you have something exotic like Conjoiner drives!!

cjameshuff
2011-Apr-11, 09:23 PM
Solar panels can function in places where algae and crops cannot grow.

Greenhouses can grow crops anywhere, and don't require ultra-pure silicon and fabrication processes like large-area, highly-controlled doping and coatings.

cjameshuff
2011-Apr-11, 09:26 PM
It would be interesting to compare the amount of research funding that has gone into nuclear fusion power generation vs. solar cell technology.

I don't have numbers, but I'm fairly sure it'd be weighted heavily on the side of solar cells. You're constantly hearing about yet another lab coming up with some variation of processes and materials to make solar cells a little bit cheaper or a little bit more efficient...such labs appear to outnumber labs working with fusion reactors by a wide margin. Working with semiconductors isn't cheap, and working with large-area semiconductors with non-standard materials and processes doesn't improve things.

baric
2011-Apr-11, 10:51 PM
I don't have numbers, but I'm fairly sure it'd be weighted heavily on the side of solar cells. You're constantly hearing about yet another lab coming up with some variation of processes and materials to make solar cells a little bit cheaper or a little bit more efficient...such labs appear to outnumber labs working with fusion reactors by a wide margin. Working with semiconductors isn't cheap, and working with large-area semiconductors with non-standard materials and processes doesn't improve things.

In fairness, I don't think you can count private-sector manufacturing costs until you want to offset them by the revenue those fabs generate.

I was speaking about the research funding that was required to make solar cells a viable technology. Much of the basic research for solar cell technology has leveraged off of closely related research for the semiconductor industry.