Set the controls for the heart of the sun
January 30, 2010 9:51 AM Subscribe
Hope for a fusion breakthrough this year.
Some of the latest experiments at the National Ignition Facility have shown that plasma problems during ignition of a fusion reaction aren't such a problem any more, prompting speculation that a prototype nuclear fusion power plant could be operating within a decade.
Some of the latest experiments at the National Ignition Facility have shown that plasma problems during ignition of a fusion reaction aren't such a problem any more, prompting speculation that a prototype nuclear fusion power plant could be operating within a decade.
Commercial nuclear fusion could be just 20 years away!
posted by Artw at 9:57 AM on January 30, 2010 [12 favorites]
posted by Artw at 9:57 AM on January 30, 2010 [12 favorites]
This is cool hot, but keep in mind that as soon as we have an unlimited supply of cheap energy we are in deeper shit than we are now.
posted by weapons-grade pandemonium at 10:04 AM on January 30, 2010 [7 favorites]
posted by weapons-grade pandemonium at 10:04 AM on January 30, 2010 [7 favorites]
There was a post around here talking about how the NIF really had nothing to do with actually building fusion plants:
The designs for actual fusion plants are Stellarators and Tokamak reactors that keep fusion reactions going by magnetically containing them. But obviously work at NIF doesn't do much good towards figuring out how to get the magnetic containment to work. At the very best, it could lead towards better computer models for fusion reactions in general.
At least that's my understanding.
posted by delmoi at 10:05 AM on January 30, 2010 [9 favorites]
My most recent book is on fusion, and I spend a bit of time discussing NIF. FuManchu is absolutely right; this is a weapons project dressed up as an energy project. For a number of reasons, NIF will never lead the way to a fusion power plant. (And, sadly, it won't be very good as a weapons project either.)Since actual fusion plants wouldn't have much to do with the way the NIF works having a 'breakthrough' at NIF won't really help anyone build a fusion plant. The NIF blasts tiny pebbles of deuterium heavy water ice, compresses them and causes fusion that way. There's not really anyway to continuously keep feeding it fuel, so even if it does output more energy then it puts in, there's no way to collect the energy to recharge the lasers or anything like that. It's basically like setting off a tiny mini-hydrogen bomb.
...
But, yes, I think that pretending that this is an energy project is a lie. I think that the fault lies with fusion scientists -- the intellectual heirs of Edward Teller -- for the deception.
The designs for actual fusion plants are Stellarators and Tokamak reactors that keep fusion reactions going by magnetically containing them. But obviously work at NIF doesn't do much good towards figuring out how to get the magnetic containment to work. At the very best, it could lead towards better computer models for fusion reactions in general.
At least that's my understanding.
posted by delmoi at 10:05 AM on January 30, 2010 [9 favorites]
Ha, no. The NIF is about producing data for computer models of nuclear weapons. They even use it to see what happens to uranium and plutonium in fission bombs and the triggers of fusion bombs. We can't test bombs directly anymore, so the point of the NIF and the computer models is to ensure that they will go off as expected despite being decades old.
It's not about power generation and never really was. The NIF design has no roadmap to a power generating plant. ITER is the power-generating fusion project you want.
posted by jedicus at 10:05 AM on January 30, 2010 [2 favorites]
It's not about power generation and never really was. The NIF design has no roadmap to a power generating plant. ITER is the power-generating fusion project you want.
posted by jedicus at 10:05 AM on January 30, 2010 [2 favorites]
here's a list of relevant articles from the Knight Science Journalism Tracker
posted by Hammond Rye at 10:09 AM on January 30, 2010
posted by Hammond Rye at 10:09 AM on January 30, 2010
The title says 2010 but the URL says 2009. I wonder when this was actually written.
posted by DU at 10:15 AM on January 30, 2010
posted by DU at 10:15 AM on January 30, 2010
The promise of "power too cheap to meter" turned out to be bullshit. On the other hand, we did get information too cheap to meter. So at least we can bitch about the power problem for a flat rate.
posted by ryanrs at 10:18 AM on January 30, 2010 [8 favorites]
posted by ryanrs at 10:18 AM on January 30, 2010 [8 favorites]
So the criticism is that you can't keep feeding it fuel, only cyclically fuel it and then produce a single pulse of energy.
While I'm sure there are a lot of major engineering challenges between here and there, this issue really didn't hurt the internal combustion engine all that much.
posted by Kid Charlemagne at 10:23 AM on January 30, 2010
While I'm sure there are a lot of major engineering challenges between here and there, this issue really didn't hurt the internal combustion engine all that much.
posted by Kid Charlemagne at 10:23 AM on January 30, 2010
> This is cool hot, but keep in mind that as soon as we have an unlimited supply of cheap energy we are in deeper shit than we are now.
No way, bro, this means I can keep driving my car everywhere all the time, only guilt-free now! Awesome!
*peels rubber out of the parking lot*
posted by you just lost the game at 10:25 AM on January 30, 2010
No way, bro, this means I can keep driving my car everywhere all the time, only guilt-free now! Awesome!
*peels rubber out of the parking lot*
posted by you just lost the game at 10:25 AM on January 30, 2010
This is cool hot, but keep in mind that as soon as we have an unlimited supply of cheap energy we are in deeper shit than we are now.
Hello why is that please thank you sir
posted by East Manitoba Regional Junior Kabaddi Champion '94 at 10:27 AM on January 30, 2010 [5 favorites]
Hello why is that please thank you sir
posted by East Manitoba Regional Junior Kabaddi Champion '94 at 10:27 AM on January 30, 2010 [5 favorites]
I think the URL was a typo. The MSNBC link was from this year.
posted by delmoi at 10:32 AM on January 30, 2010 [1 favorite]
posted by delmoi at 10:32 AM on January 30, 2010 [1 favorite]
MetaFilter: Information too cheap to meter.
posted by weapons-grade pandemonium at 10:34 AM on January 30, 2010 [5 favorites]
posted by weapons-grade pandemonium at 10:34 AM on January 30, 2010 [5 favorites]
I don't believe that they're trying to sell the NIF to the public as an energy project. It's a weapons project, it's always been a weapons project, and anyone who tells you otherwise is feeding you a line of bullshit.
It's just so incredibly cynical and disingenuous.
posted by mr_roboto at 10:35 AM on January 30, 2010
It's just so incredibly cynical and disingenuous.
posted by mr_roboto at 10:35 AM on January 30, 2010
why is that
Waste heat from the fusion plants. But never mind, we can compensate with a slight alteration of the atmosphere and/or albedo. That'll suffice until we complete the Great Space Refrigerator.
posted by ryanrs at 10:38 AM on January 30, 2010
Waste heat from the fusion plants. But never mind, we can compensate with a slight alteration of the atmosphere and/or albedo. That'll suffice until we complete the Great Space Refrigerator.
posted by ryanrs at 10:38 AM on January 30, 2010
Metafilter: bitch about it for a flat rate.
posted by ryanrs at 10:40 AM on January 30, 2010 [6 favorites]
posted by ryanrs at 10:40 AM on January 30, 2010 [6 favorites]
While I'm sure there are a lot of major engineering challenges between here and there, this issue really didn't hurt the internal combustion engine all that much.
Problem 1, the fuel: The fuel is a mix of deuterium and tritium. Tritium is quite expensive, about $84,000 to $130,000 per gram.
Problem 2, the pellets: The fuel has to be carefully grown from a seed crystal. The pellets must be used within 36 hours or they go bad due to decay of the tritium. The fuel must be precisely layered and cryogenically cooled (~19.26 K). The pellets must also be placed extremely precisely. A system for rapidly moving fuel pellets into the system while preserving these characteristics would be a massive challenge.
Problem 3, the firing rate: The as-yet-unrealized goal is to get up to 700 firings per year. The rate is limited by, amongst other things, the need for the massive lasers and flash lamps to cool down. But even at a maximum of 100MJ of energy released per firing and 700 firings per year, that's 70GJ/year, or a little over 2kW.
So, assume miraculous 100% conversion to electricity. Assume the massive engineering challenges of loading the system quickly are solved. To make it comparable to a modest nuclear powerplant would require a firing rate 100,000 times faster than their current goal. All while burning a fuel that is about 50 times more expensive than high quality diamonds, not even counting the cost of turning the fuel into pellets.
Maybe it could be turned into a fusion version of an ICE. But it would be a far better use of research money to put it into designs that actually have a reasonable shot at becoming powerplants.
posted by jedicus at 10:48 AM on January 30, 2010 [2 favorites]
Problem 1, the fuel: The fuel is a mix of deuterium and tritium. Tritium is quite expensive, about $84,000 to $130,000 per gram.
Problem 2, the pellets: The fuel has to be carefully grown from a seed crystal. The pellets must be used within 36 hours or they go bad due to decay of the tritium. The fuel must be precisely layered and cryogenically cooled (~19.26 K). The pellets must also be placed extremely precisely. A system for rapidly moving fuel pellets into the system while preserving these characteristics would be a massive challenge.
Problem 3, the firing rate: The as-yet-unrealized goal is to get up to 700 firings per year. The rate is limited by, amongst other things, the need for the massive lasers and flash lamps to cool down. But even at a maximum of 100MJ of energy released per firing and 700 firings per year, that's 70GJ/year, or a little over 2kW.
So, assume miraculous 100% conversion to electricity. Assume the massive engineering challenges of loading the system quickly are solved. To make it comparable to a modest nuclear powerplant would require a firing rate 100,000 times faster than their current goal. All while burning a fuel that is about 50 times more expensive than high quality diamonds, not even counting the cost of turning the fuel into pellets.
Maybe it could be turned into a fusion version of an ICE. But it would be a far better use of research money to put it into designs that actually have a reasonable shot at becoming powerplants.
posted by jedicus at 10:48 AM on January 30, 2010 [2 favorites]
I used to do office work for a fusion lab (MCF-related, with a few ICF-related side projects), so I'm always interested to see this kind of thing. I never got the impression that ICF was anything other than a bona fide fusion energy project -- certainly no one ever talked about it as a weapons project, and nobody DOD-related ever showed up in the lab or at any of the meetings -- but then again, I never was an engineer.
posted by PsychoTherapist at 10:50 AM on January 30, 2010
posted by PsychoTherapist at 10:50 AM on January 30, 2010
Once some sort of sustainable reaction is working, I assume it will advance the state of research around achieving fusion reactions through other means. Working models are hugely important -- even if they're inefficient and ugly.
It would be nice to live in a hopeful present again.
posted by Kikkoman at 11:00 AM on January 30, 2010 [1 favorite]
It would be nice to live in a hopeful present again.
posted by Kikkoman at 11:00 AM on January 30, 2010 [1 favorite]
It's still less stupid than hydrogen.
posted by ryanrs at 11:00 AM on January 30, 2010 [3 favorites]
posted by ryanrs at 11:00 AM on January 30, 2010 [3 favorites]
Trust me. We're humans. Give us something good, and we'll screw it up. It's kind of our post-modern thing.
posted by mccarty.tim at 11:05 AM on January 30, 2010 [2 favorites]
posted by mccarty.tim at 11:05 AM on January 30, 2010 [2 favorites]
So what is up with the Kardshian video at the bottom of the page?
posted by caddis at 11:12 AM on January 30, 2010
posted by caddis at 11:12 AM on January 30, 2010
Fusion has been "almost there" since I was a kid.
I'm old and grayhaired now, and just a few years from retirement.
posted by Chocolate Pickle at 11:13 AM on January 30, 2010 [2 favorites]
I'm old and grayhaired now, and just a few years from retirement.
posted by Chocolate Pickle at 11:13 AM on January 30, 2010 [2 favorites]
No one's mentioned Eric Lerner's's Dense Plasma Focus yet?!
Well then this is obligatory.
Also, unlike the NIF, the DFP is designed as real, prototype reactor, and had it's own ignition success.
posted by clarknova at 11:13 AM on January 30, 2010 [1 favorite]
Well then this is obligatory.
Also, unlike the NIF, the DFP is designed as real, prototype reactor, and had it's own ignition success.
posted by clarknova at 11:13 AM on January 30, 2010 [1 favorite]
Information so cheap your mom pays for it!
posted by Artw at 11:24 AM on January 30, 2010 [2 favorites]
posted by Artw at 11:24 AM on January 30, 2010 [2 favorites]
It seems there's always a breakthrough in fusion that's going to give us working reactors in ten years. It's sort of like the old Freidman Number of six months until we'd see results in Iraq.
posted by Jimmy Havok at 11:26 AM on January 30, 2010
posted by Jimmy Havok at 11:26 AM on January 30, 2010
Hello why is that please thank you sir
All this energy, whether used to run a home or car or a factory, is eventually converted to heat. If energy is cheap, billions more people will want air conditioners in summer and fusion furnaces in winter. They'll buy more cars and drive them anywhere, any time. More metal, more plastic, more garbage, more pollution, more global warming. There is no free lunch.
posted by weapons-grade pandemonium at 11:26 AM on January 30, 2010 [3 favorites]
All this energy, whether used to run a home or car or a factory, is eventually converted to heat. If energy is cheap, billions more people will want air conditioners in summer and fusion furnaces in winter. They'll buy more cars and drive them anywhere, any time. More metal, more plastic, more garbage, more pollution, more global warming. There is no free lunch.
posted by weapons-grade pandemonium at 11:26 AM on January 30, 2010 [3 favorites]
Things that have actually made life on earth better:
1. Sanitation
2. Vaccination
3. Antibiotics
4. [This space reserved for fusion power]
posted by 517 at 11:28 AM on January 30, 2010 [2 favorites]
1. Sanitation
2. Vaccination
3. Antibiotics
4. [This space reserved for fusion power]
posted by 517 at 11:28 AM on January 30, 2010 [2 favorites]
Technically we do allready have a form of fusion power that can energy-to-cheap-to-meter all over major cities, and with a space-age delivery system too!
posted by Artw at 11:30 AM on January 30, 2010 [10 favorites]
posted by Artw at 11:30 AM on January 30, 2010 [10 favorites]
Attention fusion scientists. We like surprises. Don't tell us the fusion plant is ready to operate until it's a week away.
posted by digsrus at 11:42 AM on January 30, 2010 [2 favorites]
posted by digsrus at 11:42 AM on January 30, 2010 [2 favorites]
No way, bro, this means I can keep driving my car everywhere all the time, only guilt-free now! Awesome!
*peels rubber out of the parking lot*
Crashes into fifteen other vehicles on the the gridlocked street.
posted by philip-random at 11:56 AM on January 30, 2010 [2 favorites]
*peels rubber out of the parking lot*
Crashes into fifteen other vehicles on the the gridlocked street.
posted by philip-random at 11:56 AM on January 30, 2010 [2 favorites]
Hey man, you forgot agriculture.
posted by fourcheesemac at 11:56 AM on January 30, 2010
posted by fourcheesemac at 11:56 AM on January 30, 2010
All this energy, whether used to run a home or car or a factory, is eventually converted to heat. If energy is cheap, billions more people will want air conditioners in summer and fusion furnaces in winter. They'll buy more cars and drive them anywhere, any time. More metal, more plastic, more garbage, more pollution, more global warming. There is no free lunch.
Good answer. What did the internal combustion engine promise us? Freedom to move above all else. What's it given us? Gridlock (as I just snarked about above), an increased poisoning of the air we breathe, an enthusiastic contribution to all manner of modern (and post) physical and emotional disorders.
And yet, we are moving (at times) freely in a way that was inconceivable before say 1900. And the allure of this is still with us, still, despite all the negatives, doing its bit to bring humanity together, solve problems of supply and connectedness. And, in some areas, we're actually rising up to the negatives and reconciling them too (ie: keeping the good that the internal combustion engine gives us, neutralizing the bad).
All progress creates problems. Another word for problem is challenge.
posted by philip-random at 12:06 PM on January 30, 2010
Good answer. What did the internal combustion engine promise us? Freedom to move above all else. What's it given us? Gridlock (as I just snarked about above), an increased poisoning of the air we breathe, an enthusiastic contribution to all manner of modern (and post) physical and emotional disorders.
And yet, we are moving (at times) freely in a way that was inconceivable before say 1900. And the allure of this is still with us, still, despite all the negatives, doing its bit to bring humanity together, solve problems of supply and connectedness. And, in some areas, we're actually rising up to the negatives and reconciling them too (ie: keeping the good that the internal combustion engine gives us, neutralizing the bad).
All progress creates problems. Another word for problem is challenge.
posted by philip-random at 12:06 PM on January 30, 2010
@jeducious: Can you elaborate on the 36 hour limit? I thought the half-life of Tritium was about 12.5 years - so why would decay limit it to 36 hours - is it just that the mix is so precise, or something else?
posted by TravellingDen at 12:59 PM on January 30, 2010
posted by TravellingDen at 12:59 PM on January 30, 2010
So the criticism is that you can't keep feeding it fuel, only cyclically fuel it and then produce a single pulse of energy.As far as I know, no one has ever built a solid fuel internal combustion engine, but more to the point the thing isn't anything like a power plant. It's like setting a puddle of gasoline on fire with a magnifying glass you're holding in your hand. It will probably release more energy then it takes in sunlight, but the design is nothing at all like an actual engine.
While I'm sure there are a lot of major engineering challenges between here and there, this issue really didn't hurt the internal combustion engine all that much.
Again, this might get people some good data for computer models, but it really has nothing to do with building a power plant. The other designs are nothing like this and are more likely to yeild an actual working power plant (from my understanding)
posted by delmoi at 1:02 PM on January 30, 2010
Hello why is that please thank you sir
All this energy, whether used to run a home or car or a factory, is eventually converted to heat. If energy is cheap, billions more people will want air conditioners in summer and fusion furnaces in winter. They'll buy more cars and drive them anywhere, any time. More metal, more plastic, more garbage, more pollution, more global warming. There is no free lunch.
Hmmmm. I'm cynical, but not that cynical. Back-of-the-envelope calculation:
I grabbed a figure from somewhere on wikipedia that current energy consumption in the US is about 12 kW per person (let's define that to be luxurious/wasteful energy use). I don't know if that number is for end use, or primary energy - but let's say it's end use, and that there is 25% efficiency in producing it with whatever magical new non-fossil "consumable energy" producing devices we come up with in the future.
Now let's imagine a future world of 15 billion people. All consuming 12 kW, and then wasting another 36 kW in heat into the atmosphere. That's 48 kW total (since the consumed 12 eventual dissipates into heat too).
That's human beings releasing 7.2^14 W of heat.
Every day, the earth receives 1.740×10^17 W from the Sun (at the upper atmosphere).
So, in this hypothetical future world of energy excess, we increase the heat contribution to our rock by 0.41%.
Since that heat is being released underneath the clouds, at groundlevel (or thereabouts), it's going to have a bigger impact on the climate than just 0.41%.
But then again, Western Europe's energy consumption is half that of the US and the standard of living is similar, and 25% overall efficiency is crap (waste heat from magic energy producer can be piped and used for process and space heating).
So really - is waste heat such a legitimate concern?
posted by molecicco at 1:22 PM on January 30, 2010 [4 favorites]
All this energy, whether used to run a home or car or a factory, is eventually converted to heat. If energy is cheap, billions more people will want air conditioners in summer and fusion furnaces in winter. They'll buy more cars and drive them anywhere, any time. More metal, more plastic, more garbage, more pollution, more global warming. There is no free lunch.
Hmmmm. I'm cynical, but not that cynical. Back-of-the-envelope calculation:
I grabbed a figure from somewhere on wikipedia that current energy consumption in the US is about 12 kW per person (let's define that to be luxurious/wasteful energy use). I don't know if that number is for end use, or primary energy - but let's say it's end use, and that there is 25% efficiency in producing it with whatever magical new non-fossil "consumable energy" producing devices we come up with in the future.
Now let's imagine a future world of 15 billion people. All consuming 12 kW, and then wasting another 36 kW in heat into the atmosphere. That's 48 kW total (since the consumed 12 eventual dissipates into heat too).
That's human beings releasing 7.2^14 W of heat.
Every day, the earth receives 1.740×10^17 W from the Sun (at the upper atmosphere).
So, in this hypothetical future world of energy excess, we increase the heat contribution to our rock by 0.41%.
Since that heat is being released underneath the clouds, at groundlevel (or thereabouts), it's going to have a bigger impact on the climate than just 0.41%.
But then again, Western Europe's energy consumption is half that of the US and the standard of living is similar, and 25% overall efficiency is crap (waste heat from magic energy producer can be piped and used for process and space heating).
So really - is waste heat such a legitimate concern?
posted by molecicco at 1:22 PM on January 30, 2010 [4 favorites]
The waste heat is not nearly as much of a problem as keeping all that heat from all sources (sun, waste) from escaping the atmosphere--the classic Greenhouse Effect.
This is made worse by increasing amounts of CO2 in the atmosphere, which is exactly what many of our energy sources do. So having a power plant that doesn't do this is definitely a win.
That said, we are many years and many, many billions of dollars away from a practical energy producing fusion reactor. In the mean time, it's a nice dream.
posted by eye of newt at 1:42 PM on January 30, 2010
This is made worse by increasing amounts of CO2 in the atmosphere, which is exactly what many of our energy sources do. So having a power plant that doesn't do this is definitely a win.
That said, we are many years and many, many billions of dollars away from a practical energy producing fusion reactor. In the mean time, it's a nice dream.
posted by eye of newt at 1:42 PM on January 30, 2010
All this energy, whether used to run a home or car or a factory, is eventually converted to heat. If energy is cheap, billions more people will want air conditioners in summer and fusion furnaces in winter. They'll buy more cars and drive them anywhere, any time. More metal, more plastic, more garbage, more pollution, more global warming. There is no free lunch.
We already know how to reduce CO2 and replenish O2: plants. If we had unlimited cheap energy we would have little difficulty in building as many massive algae-containing structures as we like.
We could shoot our polluting garbage into deep space.
I agree that there is no free lunch in a closed system, but the earth is not a closed system.
posted by East Manitoba Regional Junior Kabaddi Champion '94 at 1:43 PM on January 30, 2010 [1 favorite]
We already know how to reduce CO2 and replenish O2: plants. If we had unlimited cheap energy we would have little difficulty in building as many massive algae-containing structures as we like.
We could shoot our polluting garbage into deep space.
I agree that there is no free lunch in a closed system, but the earth is not a closed system.
posted by East Manitoba Regional Junior Kabaddi Champion '94 at 1:43 PM on January 30, 2010 [1 favorite]
@jedicus: Can you elaborate on the 36 hour limit? I thought the half-life of Tritium was about 12.5 years - so why would decay limit it to 36 hours - is it just that the mix is so precise, or something else?
Part of it is that the DT mix is precise, but the biggest part is that the tritium does not decay into deuterium or protium; it decays into helium-3. It doesn't take much helium to prevent the inertial confinement fusion from working properly. Deuterium-tritium fusion is the easiest fusion reaction; fusing helium with either one is much harder and fusing helium with helium is harder still.
It's a little bit like how the uranium in a fission bomb must be very highly enriched in order to work well, except more so.
posted by jedicus at 2:06 PM on January 30, 2010 [1 favorite]
Part of it is that the DT mix is precise, but the biggest part is that the tritium does not decay into deuterium or protium; it decays into helium-3. It doesn't take much helium to prevent the inertial confinement fusion from working properly. Deuterium-tritium fusion is the easiest fusion reaction; fusing helium with either one is much harder and fusing helium with helium is harder still.
It's a little bit like how the uranium in a fission bomb must be very highly enriched in order to work well, except more so.
posted by jedicus at 2:06 PM on January 30, 2010 [1 favorite]
Why, this isn't about about a rebirth of fusion at all! How misleading!
posted by paisley henosis at 2:17 PM on January 30, 2010
posted by paisley henosis at 2:17 PM on January 30, 2010
And thank Satan for that.
posted by philip-random at 2:33 PM on January 30, 2010 [2 favorites]
posted by philip-random at 2:33 PM on January 30, 2010 [2 favorites]
One thing that never seems explained too well in articles is how to create electricity from fusion. Wikipedia says that heat is transfered and is used to drive steam turbines as conventional fission plants do.
Is this the only way?
posted by bottlebrushtree at 5:08 PM on January 30, 2010
Is this the only way?
posted by bottlebrushtree at 5:08 PM on January 30, 2010
Steam turbines are a mature technology and they work very well. That's how coal-fired electric generation plants work, and it's how nuclear plants work.
Yeah, it's pretty much the only reasonable way to make electricity from fusion -- but it's a really good way. There's no reason to look for any other approach.
posted by Chocolate Pickle at 5:34 PM on January 30, 2010
Yeah, it's pretty much the only reasonable way to make electricity from fusion -- but it's a really good way. There's no reason to look for any other approach.
posted by Chocolate Pickle at 5:34 PM on January 30, 2010
Yeah, if energy is infinitely available and vanishingly cheap, we'll find new, innovative ways to cool the planet. A gigantic, colossal refrigerator say, and we'll just leave the door open all the time. See?
posted by newdaddy at 5:35 PM on January 30, 2010 [1 favorite]
posted by newdaddy at 5:35 PM on January 30, 2010 [1 favorite]
Someone in our society worrying about waste heat from cheap energy is like someone gorging on pie worrying about their hair growing and making them get heavier. Put it out of your mind, it is insignificant in the face of the genuine problem we are facing.
posted by Humanzee at 5:43 PM on January 30, 2010
posted by Humanzee at 5:43 PM on January 30, 2010
Whoever designed that blogspot page must be kept away from the fusion machines or we're all doomed.
posted by neuron at 6:08 PM on January 30, 2010
posted by neuron at 6:08 PM on January 30, 2010
It is possible to synthesize excited bromide in an argon matrix. It's an excimer frozen in its excited state. It's a chemical laser but in solid, not gaseous, form. Put simply it's like lasing a stick of dynamite.
As soon as we apply a field, we couple to a state, it is radiatively coupled to the ground state. I figure we can extract at least 10 to the 21st photons per cubic centimeter which will give one kilojoule per cubic centimeter at 600 nanometers, or, one megajoule per liter.
posted by Bonzai at 7:45 PM on January 30, 2010 [1 favorite]
As soon as we apply a field, we couple to a state, it is radiatively coupled to the ground state. I figure we can extract at least 10 to the 21st photons per cubic centimeter which will give one kilojoule per cubic centimeter at 600 nanometers, or, one megajoule per liter.
posted by Bonzai at 7:45 PM on January 30, 2010 [1 favorite]
bottlebrushtree: “Is [generating steam to turn turbines] the only way?”
No, but it's a pretty good way, and it's a way we're very familiar with and have pretty much taken to the practical limits of efficiency.
You're correct that there are other ways of generating electricity. Thermocouples have the benefit of not having any moving parts, and are used on some space probes (and occasionally here on earth) along with heat-producing isotopes. They're not very efficient, though.
In fact, the next generation of space probes may actually use Stirling engines, which is another choice. They're heat engines, but use a simpler closed-loop configuration than a typical Rankine-cycle turbine system. I think there is/was some interest in using them in nuclear power plants, but the problem here is that since they're subject to the same fundamental limits as turbine systems, they have to have a huge implementation advantage to be advantageous overall. And with all the experience (and economies of scale) in steam systems, it only goes in their favor in very special cases.
It might be possible to construct some sort of photo-voltaic system that was tuned for very high-energy photons (gamma and x-rays), which would let you use some of the radiation resulting from nuclear reactions directly ... but I doubt it would be as efficient as just turning their energy into heat via shielding and then using the heat.
There are probably some other ways of generating electricity more directly (some sort of thermo-electrochemical process?), but none that come to mind as being particularly good candidates for large-scale power generation.
It's worth pointing out though that the "steam turbine" systems used in modern power plants — particularly big fossil-fuel ones (which are, sadly, actually more sophisticated than current nuclear plants) — are not some sort of clanking old 19th century technology. Some newer powerplants use supercritical water as a working fluid, so they're not really "boiling" water at all. By keeping the water above its critical point, it never actually changes states; it just gets less dense. That allows some more efficiency to be squeezed out of the whole system. (Although the supercritical water may be used to generate steam in other coolant loops, in addition to doing mechanical work directly.)
I'm not sure if a supercritical water system is really a Rankine-cycle heat engine anymore; it looks more like the Carnot cycle to me, but maybe it just shows that those divisions aren't necessarily that meaningful, except from a historical perspective.
Although the same trick that is performed with supercritical water can be done with other working fluids as well, water is cheap, well-studied, compatible with a wide range of materials (compared to, say, sodium), has a high heat capacity, and is easily available. You'd have to come up with a pretty compelling reason not to use it, really.
posted by Kadin2048 at 10:43 PM on January 30, 2010
No, but it's a pretty good way, and it's a way we're very familiar with and have pretty much taken to the practical limits of efficiency.
You're correct that there are other ways of generating electricity. Thermocouples have the benefit of not having any moving parts, and are used on some space probes (and occasionally here on earth) along with heat-producing isotopes. They're not very efficient, though.
In fact, the next generation of space probes may actually use Stirling engines, which is another choice. They're heat engines, but use a simpler closed-loop configuration than a typical Rankine-cycle turbine system. I think there is/was some interest in using them in nuclear power plants, but the problem here is that since they're subject to the same fundamental limits as turbine systems, they have to have a huge implementation advantage to be advantageous overall. And with all the experience (and economies of scale) in steam systems, it only goes in their favor in very special cases.
It might be possible to construct some sort of photo-voltaic system that was tuned for very high-energy photons (gamma and x-rays), which would let you use some of the radiation resulting from nuclear reactions directly ... but I doubt it would be as efficient as just turning their energy into heat via shielding and then using the heat.
There are probably some other ways of generating electricity more directly (some sort of thermo-electrochemical process?), but none that come to mind as being particularly good candidates for large-scale power generation.
It's worth pointing out though that the "steam turbine" systems used in modern power plants — particularly big fossil-fuel ones (which are, sadly, actually more sophisticated than current nuclear plants) — are not some sort of clanking old 19th century technology. Some newer powerplants use supercritical water as a working fluid, so they're not really "boiling" water at all. By keeping the water above its critical point, it never actually changes states; it just gets less dense. That allows some more efficiency to be squeezed out of the whole system. (Although the supercritical water may be used to generate steam in other coolant loops, in addition to doing mechanical work directly.)
I'm not sure if a supercritical water system is really a Rankine-cycle heat engine anymore; it looks more like the Carnot cycle to me, but maybe it just shows that those divisions aren't necessarily that meaningful, except from a historical perspective.
Although the same trick that is performed with supercritical water can be done with other working fluids as well, water is cheap, well-studied, compatible with a wide range of materials (compared to, say, sodium), has a high heat capacity, and is easily available. You'd have to come up with a pretty compelling reason not to use it, really.
posted by Kadin2048 at 10:43 PM on January 30, 2010
Thorium.
posted by CarlRossi at 10:54 PM on January 30, 2010 [1 favorite]
posted by CarlRossi at 10:54 PM on January 30, 2010 [1 favorite]
Unobtainium?
posted by philip-random at 11:37 PM on January 30, 2010
posted by philip-random at 11:37 PM on January 30, 2010
In fact, the next generation of space probes may actually use Stirling engines, which is another choice. They're heat engines, but use a simpler closed-loop configuration than a typical Rankine-cycle turbine system.
How are they going to release excess heat quickly enough?
posted by delmoi at 6:33 AM on January 31, 2010
How are they going to release excess heat quickly enough?
posted by delmoi at 6:33 AM on January 31, 2010
Just putting this out there: Space Solar, Beamed Microwave. There are no clouds in geostationary orbit, and it's the perfect opportunity to learn how to launch things into space CHEAPLY.
posted by mikelieman at 7:25 AM on January 31, 2010
posted by mikelieman at 7:25 AM on January 31, 2010
The great thing about space-based solar power is that we have all the tech for it right now, all we need is the will to start doing it. The cost would probably be on about the same scale as the Iraq war, from the numbers I've seen.
posted by Jimmy Havok at 11:15 AM on January 31, 2010
posted by Jimmy Havok at 11:15 AM on January 31, 2010
Space solar doesn't really make any more sense than land solar. Sure, there is no cloud cover, and you don't lose solar energy as it travels through the air, but the extra cost of taking the stuff up there, and maintaining the infrastructure in space and on the ground is just not worth it. It would be easier and cheaper to just build huge fields of panels/parabolas/towers in the desert and use high-voltage DC to distribute the electricity to where it is needed.
posted by molecicco at 12:15 PM on January 31, 2010
posted by molecicco at 12:15 PM on January 31, 2010
How are they going to release excess heat quickly enough?
I assume lots of cooling fins, so that heat is removed via infrared blackbody radiation, but there might be intermediate cooling loops between the Stirling engine's working fluid and the actual heat sinks. My guess would be that heat-removal is the limiting factor and probably the biggest engineering challenge in such a setup.
But you run into that problem with thermocouples as well; they require both a hot and a cold side in order to produce current. My understanding of current designs (like those used on Cassini and Pioneer) is that they're cylinders, with the "hot" side of the thermocouples on the inside, in contact with the radioisotope heat source, and the "cold" side on the outside, connected to heat sink fins that radiate away heat into space.
posted by Kadin2048 at 12:46 PM on January 31, 2010
I assume lots of cooling fins, so that heat is removed via infrared blackbody radiation, but there might be intermediate cooling loops between the Stirling engine's working fluid and the actual heat sinks. My guess would be that heat-removal is the limiting factor and probably the biggest engineering challenge in such a setup.
But you run into that problem with thermocouples as well; they require both a hot and a cold side in order to produce current. My understanding of current designs (like those used on Cassini and Pioneer) is that they're cylinders, with the "hot" side of the thermocouples on the inside, in contact with the radioisotope heat source, and the "cold" side on the outside, connected to heat sink fins that radiate away heat into space.
posted by Kadin2048 at 12:46 PM on January 31, 2010
Just putting this out there: Space Solar, Beamed Microwave. There are no clouds in geostationary orbit, and it's the perfect opportunity to learn how to launch things into space CHEAPLY.
Let me know when you've solved the problem of cheap bulk delivery of cargo to high Earth orbit. I'll be first in line with a design for a space power station.
But cheap bulk delivery to orbit appears to be an even more intractable problem than making fusion exothermic.
posted by Chocolate Pickle at 6:59 PM on January 31, 2010
Let me know when you've solved the problem of cheap bulk delivery of cargo to high Earth orbit. I'll be first in line with a design for a space power station.
But cheap bulk delivery to orbit appears to be an even more intractable problem than making fusion exothermic.
posted by Chocolate Pickle at 6:59 PM on January 31, 2010
It's still less stupid than hydrogen.
Reasoning on why hydrogen is stupid, ryanrs? Empty snark is empty.
posted by IAmBroom at 8:52 PM on January 31, 2010
Reasoning on why hydrogen is stupid, ryanrs? Empty snark is empty.
posted by IAmBroom at 8:52 PM on January 31, 2010
Because it's extremely difficult to store a reasonably large amount of energy in a reasonably small space with hydrogen without liquifying it, which in turn means it can't be stored for long periods of time without it boiling away.
And because there isn't any natural source of hydrogen for us to tap. Hydrogen is like electricity: a way of moving energy from one place to another. It isn't an energy source.
posted by Chocolate Pickle at 10:39 PM on January 31, 2010
And because there isn't any natural source of hydrogen for us to tap. Hydrogen is like electricity: a way of moving energy from one place to another. It isn't an energy source.
posted by Chocolate Pickle at 10:39 PM on January 31, 2010
breakthrough in fusion
power of the sun
last time i heard something like this some dude got four robotic arms welded to his back
posted by chalbe at 8:38 AM on February 1, 2010 [1 favorite]
power of the sun
last time i heard something like this some dude got four robotic arms welded to his back
posted by chalbe at 8:38 AM on February 1, 2010 [1 favorite]
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This padding, it is as soft as ten billion couch cushions.
posted by griphus at 9:57 AM on January 30, 2010 [3 favorites]