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Post by dpidz0r on Feb 27, 2017 18:15:31 GMT
Supposedly the only thing keeping fusion from being a reality is reliably containing the superheated plasma, and keeping it from destroying the reactor that surrounds it. Granted I may be way out of date here or talking about the wrong kind of fusion reactor, but iirc from the facility I toured a few years ago, destroying the reactor wasn't really a concern if the plasma lost containment. There's so little thermal mass the reaction just stops if the stream hits the wall.
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Post by thorneel on Feb 27, 2017 18:21:48 GMT
thorneel - Every such combination has one used more than others. Maybe not overpoweringly dominant, but dominant nonetheless. Then I would say fission: it has enormous inertia when existing, is already quite widely used, there are big efforts to develop it in China and India which by itself is an enormous market for energy, and they are the only practical option beside fossil fuel, which I expect to decline - every other practical system is specialised for particular geography and generally is not enough by itself. Also, I don't expect hydrothermal energy to make any significant impact, though we may see a few of those this century.
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Post by deltav on Feb 27, 2017 18:58:17 GMT
Supposedly the only thing keeping fusion from being a reality is reliably containing the superheated plasma, and keeping it from destroying the reactor that surrounds it. Granted I may be way out of date here or talking about the wrong kind of fusion reactor, but iirc from the facility I toured a few years ago, destroying the reactor wasn't really a concern if the plasma lost containment. There's so little thermal mass the reaction just stops if the stream hits the wall. Ah I see my use of the word "destroyed" was unfortunate. Should have used "damaged" or "scarred". Edit that one word to say:"Supposedly the only thing keeping fusion from being a reality is reliably containing the superheated plasma, and keeping it from (scarring) the reactor that surrounds it." From my link: "Our sun contains plasma with its immense gravity, but here on Earth, we need powerful magnets or lasers to do so. And the margins for error are miniscule. A teensy amount of escaped plasma can scar the wall of a fusion reactor, causing the machine to shut down." Point taken. Don't let the poor choice of that one word distract you. My point is that the problem of fusion is one of containing and maintaining the superheated plasma, without which the fusion reaction stops. Currently the record is 102 seconds it seems. If that is solved, we would have fusion power (as I understand it).
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Post by Enderminion on Feb 27, 2017 20:17:55 GMT
I guess a big problem is getting people to approve what they think is a MASSIVE EFFING BOMB under their house
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Post by Pttg on Feb 27, 2017 20:35:09 GMT
Solar PV currently has worse efficiency than solar thermal, and has the energy storage issue. Industrial processes require heat, and converting light to electricity and back to heat is a poor design choice. We will see solar panels on roofs everywhere, but probably not powering steel mills. There are multiple kinds of efficiency. Solar thermal captures a larger portion of the sunlight that falls on the collection area, that is true. However, sunlight is free. Solar equipment, sodium, and turboelectric generators are not. The only thing that matters for civilian energy production is total levelized $/MWh, and in an ideal world that cost includes the effect of laws enforcing externalities. As it stands today, PV is the cheapest source of power during the day, and once storage is factored in it's still cheapest in many parts of the world. As storage grows cheaper that's only getting faster. It's fast to build, and individual homeowners can build it themselves. Solar thermal, on the other hand, is a utility-scale effort, and it costs twice what PV does. I can get solar batteries that outlast PV. Fusion... I love fusion. But at current investment levels it's never happening. It likely does work, but between ITER sucking all the air out of the room and extremely limited spending, we're going to run out of fossil fuels before we switch to fusion. If someone would fund polywells then we'd have something worth talking about. Fission would be nice if we lived in the CoaDE universe, where reactors are solid-state and never have problems. Hydroelectric is neat. It's also extremely cheap. It's just quite limited in places where we need electricity, and it also produces methane when it floods the new lakebed.
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Post by newageofpower on Feb 27, 2017 20:43:50 GMT
Fission and some chemical (read- coal, gas) is probably the only way to produce large amounts of stable load-power on demand.
However, if mankind begins deindustrializing, increasing efficiency and generally use less power per capita, we may be able to get by with 70% or more renewable power.
I'm not actually a fan of this scenario.
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Post by Pttg on Feb 28, 2017 2:15:57 GMT
Fission and some chemical (read- coal, gas) is probably the only way to produce large amounts of stable load-power on demand. However, if mankind begins deindustrializing, increasing efficiency and generally use less power per capita, we may be able to get by with 70% or more renewable power. I'm not actually a fan of this scenario. Storage is cheap and getting cheaper. Throw in wind, hydro, and the ultimate of eternal power supplies, tidal, and 100% renewable is a matter of inertia. That said, using nuclear power as a stepping stone to total renewables is not necessarily bad, especially if we use it to recycle weapons-grade fissiles. I think "deindustrialization" isn't really a concern we're going to have in the future. Beyond the fact that nobody outside of treehouse hippies is arguing for it, within 50 years it's not really clear that employment and industry is going to work anything like how it does now. ....Solar photovoltaic is still immature, expensive, and actually building the solar panels creates pollution, let alone disposing of old ones. Still, constant progresses are made, maybe they will be a great solution for high-sunlight nations in the next decades. Also, it only works during the day - intermittent generation is a much, much bigger problem than advertised.... Solar thermal is simpler, more durable, less pollution-prone and probably a better solution for large powerplants in those high-sunlight places. And it can be tuned to work h/24. Wind kinetic is also immature. Wind generators are expensive, too big (they crush the landscape, which is bad for locals/tourism), damage the local soil (they require a big bad concrete foundation, generally in the middle of fertile lands), fragile and generally more impractical than advertised. The intermittent generation problem is even worse than solar pv, and harder to plan for to boot. However, new technologies like flying windgen could change all that, and make it great for local power for high-wind places. ...Where do people get their information about renewables? PV panels pay back their production costs many times over (Energy and $). They are 1/130th the cost they were 40 years ago. They can be recycled in the production of new ones, and even if thrown away produce astronomically less waste per KWh than coal. They're already cost-effective as far north as Denmark. Storage is also decreasing in cost rapidly. Solar thermal, in contrast, has many more moving parts, is much more prone to breakdown, and heck, if the sodium tanks burst that's no picnic either. It's weird seeing someone get the whole thing entirely backwards. Sure, it has built in storage, but it's thermal storage, which constantly bleeds power heating up the area around it. I've seen nice work on wind, it seems to pay for itself. I wonder about the argument that wind turbines damage the landscape. Like, do people imagine that coal just appears magically and the ash vanishes afterwards? I'm sorry if this comes across as a screed, It's just that I've put a lot of study into this and I feel frustrated when people get caught up in misinformation or just old news.
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Post by Easy on Feb 28, 2017 3:36:50 GMT
I'd like to see a molten fission reactor. Where all the little bits can get as hot as they please and there is no worry of meltdown because it has already melted down.
In practice it would probably be like the hydrogen bomb molten salt power plants, where you detonate a nuclear bomb in metal salt and then use that latent heat source for however many months it lasts and you need to detonate a new bomb. That is is technically fusion power.
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Post by deltav on Feb 28, 2017 6:43:34 GMT
I'd like to see a molten fission reactor. Where all the little bits can get as hot as they please and there is no worry of meltdown because it has already melted down. In practice it would probably be like the hydrogen bomb molten salt power plants, where you detonate a nuclear bomb in metal salt and then use that latent heat source for however many months it lasts and you need to detonate a new bomb. That is is technically fusion power. I thought a melt down is when the reaction get too hot for the reactor to contain no? "melt down 2.(of a nuclear reactor) undergo a catastrophic failure as a result of the fuel overheating."
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Post by thorneel on Feb 28, 2017 11:45:37 GMT
...Where do people get their information about renewables? PV panels pay back their production costs many times over (Energy and $). They are 1/130th the cost they were 40 years ago. They can be recycled in the production of new ones, and even if thrown away produce astronomically less waste per KWh than coal. They're already cost-effective as far north as Denmark. Storage is also decreasing in cost rapidly. Solar thermal, in contrast, has many more moving parts, is much more prone to breakdown, and heck, if the sodium tanks burst that's no picnic either. It's weird seeing someone get the whole thing entirely backwards. Sure, it has built in storage, but it's thermal storage, which constantly bleeds power heating up the area around it. I've seen nice work on wind, it seems to pay for itself. I wonder about the argument that wind turbines damage the landscape. Like, do people imagine that coal just appears magically and the ash vanishes afterwards? I'm sorry if this comes across as a screed, It's just that I've put a lot of study into this and I feel frustrated when people get caught up in misinformation or just old news. PV is so cheap because some nations are doing PV dumping, and some nations (not necessarily the same) are massively subsidising its use. Which would not necessarily be a bad thing (apart from the part where dumping is intended to break other nations' PV industry, probably to raise the price later) if we did actually know how to dispose of old PV panels. Because nothing says renewable like dumping a whole new ecological problem on the next generation. Of course, if someone found a process to dispose them in a relatively clean manner since last time I checked, I will be happy to completely reverse my opinion. And I do expect to reverse it some day. I don't expect it to be this decade, though. Storage is making progress, but it is still woefully short of what we would actually need. Reusing old electric car batteries for storage is a great idea, and will help unless someone manages to screw it up on a non-technical level, but it won't be enough. And even if it is, massive installations of high-energy batteries full of nasty chemicals is more risky than people realise. Maybe we will find a way to store immense amounts of energy in high-end superconductors based on mostly non-polluting components, though remember that the more energy you store in something, the more it will want to make a bigger boom. Storing one day of production from, say, a 4 GW nuclear powerplant, that's a 82.6 kt eq. TNT bomb. So the inherent storage of solar-thermal, even with its ultimately quite lower energy efficiency, is a pretty nice thing to have. Sure, molten salt is not nice, and spillage may will happen. But if it is at least somewhat reasonably built, spillage won't spread and contaminate the surroundings. Granted, "at least somewhat reasonably built" is probably too hard for some contractors, so accidents will happen. At least I hope they will be smart enough to put them far away from people, like in hot deserts with no groundwater nearby to pollute. The counterpoint is that for places with predictable enough sunlight/wind, storage issues can be mitigated by power use. As of today, there are already places where energy-hungry industries are run at night to balance consumption from constant-production nuclear powerplants. Rationalising energy use, you can consume more during peak production. Then there's the little things like solar-thermal balloons, or local heat storage (which is easier than electric solar-thermal). Also, comparing any energy source to coal will work only if it is somehow worse. Coal is evil. Coal is hell. Coal has killed more people than any other energy source (probably combined). Coal hates you. Coal wants to eat your lungs. Coal released more radioactive material in atmosphere than nuclear energy, accidents included. Coal is what you use when you loathe people. The only energy source worse than coal would be burning people with fluorine. Coal is the Godwin point of energy sources. Coal can actually be made less heinously polluting, like making it only quite bad, but most coal powerplants are angry old things that hate you and your newfanged electronics and your loud music and just want to make you die of cancer. Hrm... er What I mean is that you should compare the impact of windgen to, say, solar or fission, not the single worst thing there is out there. Another minor source of energy is wood. You can't grow enough forests for this to cover even a large fraction of our energy needs, but it is a nice solution for local backup power for rural places. The most efficient idea is to use a wood heater (heating can consume quite a bit of energy) and put a generator on it to convert some 20% of the energy into electricity. With a good installation, pollution is negligible, and it won't release nasty elements in the atmosphere (well, unless you burn wood from Prypat) or the powerplant itself create environmental problems. (Also it is slightly CO2-negative, if you pay attention to that) And yes, wood is the greenest energy there is, as the most efficient way to get burning wood is a side-product of a well-cared forest, after all the bits useful for something else have been sold. But it won't become anything major as the kW/kmĀ² for forests is too low and there is simply not enough surface on Earth. Interestingly, this may be why coal use was one factor for the Industrial Revolution, as it was too energy-hungry to be fuelled only by forests. About tidal sea powerplants, did the costs go down recently? Last time I heard, it was too expensive to be usable. There is an old prototype plant still working in France, but it is the single most expensive plant in the country per kW/h. But it is an old one, so what progress has been made since?
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Post by Rocket Witch on Feb 28, 2017 13:31:37 GMT
Where's muh biomass option? I don't expect biofuels to supply grid power, but I don't see why they couldn't seamlessly supplant fossil petrochemicals for cars, heating, etc.
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Post by darthroach on Feb 28, 2017 15:06:24 GMT
None of the ones listed. Solar Power Satellites. Leave the fissionables for rocket fuel.
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Post by Pttg on Feb 28, 2017 18:09:54 GMT
None of the ones listed. Solar Power Satellites. Leave the fissionables for rocket fuel. I did the math for those. The hard part is making use of the electricity. Microwave broadcasting takes up about as much space as solar power does, and people don't want to live near it.
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Post by Enderminion on Feb 28, 2017 18:12:00 GMT
None of the ones listed. Solar Power Satellites. Leave the fissionables for rocket fuel. I did the math for those. The hard part is making use of the electricity. Microwave broadcasting takes up about as much space as solar power does, and people don't want to live near it. AHHH radiation AHHH run away!!!
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Post by teeth on Feb 28, 2017 18:13:31 GMT
I've heard that the current uranium supplies would only last a few years if scaled up to supply all the worlds energy needs, how true is that and how far can it be extended with more efficient reactors and waste burning reactors?
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