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silence_kit posted:That's a little hard to believe. Do you have a source for that?
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# ? Jun 9, 2013 02:00 |
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# ? May 10, 2024 01:09 |
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VikingofRock posted:Wait, really? Could you source that? I always assumed that pressure would be far and away the biggest source of heat at the core. For pressure to be heating up the core, it would have to be doing work, which would mean the Earth would have to be shrinking... EDIT: VVV Right, and that residual heat was from when the Earth was actually shrinking into the ball of fun it is today. ohgodwhat fucked around with this message at 04:59 on Jun 9, 2013 |
# ? Jun 9, 2013 04:26 |
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ohgodwhat posted:For pressure to be heating up the core, it would have to be doing work, which would mean the Earth would have to be shrinking... Wikipedia: quote:The Earth's internal heat comes from a combination of residual heat from planetary accretion (about 20%) and heat produced through radioactive decay (80%)
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# ? Jun 9, 2013 04:35 |
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silence_kit posted:If you actually read your own report that you posted, it concludes that the only public health issue identified with crystalline silicon solar cell manufacturing is the lead solder in the packaging of the solar cells. When you throw away the cell, the lead can get into other things. I am not super-knowledgeable about electronics packaging technology, but I have heard that they are switching away from lead-based solders. Are you addressing me or someone else? I wasn't talking about decommissioning. I was talking about trying to find the quantity of chemicals required to fabricate solar PV.
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# ? Jun 9, 2013 17:18 |
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Office Thug posted:Are you addressing me or someone else? I wasn't talking about decommissioning. I was talking about trying to find the quantity of chemicals required to fabricate solar PV. Oh. The link you posted then isn't relevant to your question.
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# ? Jun 9, 2013 18:47 |
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hobbesmaster posted:Nuclear is not renewable. No energy source is truly renewable. Biofuels deplete phosphorus, solar and wind require rare earths, radioactive elements will eventually decay to stability and the Earth's core will cool, the Sun will burn out, etc. If an energy source will buy us another thousand years and reduce the havoc caused by fossil fuels we need to take it. Now, the more meaningful question. How can the net amount of entropy in the universe be massively decreased? There is as yet insufficient data for a meaningful answer. Paul MaudDib fucked around with this message at 19:11 on Jun 9, 2013 |
# ? Jun 9, 2013 19:01 |
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Paul MaudDib posted:solar and wind require rare earths, Not true. I have spent the last couple of posts in this thread explaining that the dominant solar cell technology, crystalline silicon, does not have an element scarcity problem. Paul MaudDib posted:Now, the more meaningful question. How can the net amount of entropy in the universe be massively decreased? There is as yet insufficient data for a meaningful answer. I am not the world's biggest thermodynamics buff, but I think your "meaningful question" may better be rephrased "can we break the second law of thermodynamics?" Most people tend to believe in the second law of thermodynamics. . .
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# ? Jun 9, 2013 19:37 |
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http://www.theage.com.au/comment/japans-radiation-disaster-toll-none-dead-none-sick-20130604-2nomz.html posted:Heard much about Fukushima lately? You know, the disaster that spread deadly contamination across Japan and spelt the end for the nuclear industry. Considering that even the cancer rate estimates anti-nuclear people have come up with are in the ballpark of the number of people killed by the evacuation procedures, I think the following comment from another forum is pretty apt: "Fukushima should have been the ultimate Triumph of Nuclear power for the rest of the world. Nuclear power proponents should have immediately gone on all forms of media to say 'Here we have a nuclear power plant, that had piss poor safety run on it, the company involved was rather incompetent, it got hit by a massive Earthquake, and THEN a massive Tsunami, and the worse that happened was ONE out of the FOUR reactors partially melted down. Oh yeah, and NO ONE DIED from it.'"
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# ? Jun 9, 2013 19:42 |
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Paul MaudDib posted:No energy source is truly renewable. Biofuels deplete phosphorus, solar and wind require rare earths, radioactive elements will eventually decay to stability and the Earth's core will cool, the Sun will burn out, etc. If an energy source will buy us another thousand years and reduce the havoc caused by fossil fuels we need to take it. You have to dig uranium (and fossil fuels) out of the ground and cart it to a reactor. Individual mines can be depleted and will not have uranium in them again. For solar and wind you leave the windmills/panels in place and let the sun do its thing. For hydro you let the weather keep replenishing your river. For geothermal you dig a hole and the Earth will keep you warm. For biofuels you keep growing crops on the same fields year after year. The distinction is one of logistics; it has nothing to do with whether some energy source is "good" or bad.
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# ? Jun 9, 2013 19:54 |
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hobbesmaster posted:You have to dig uranium (and fossil fuels) out of the ground and cart it to a reactor. Individual mines can be depleted and will not have uranium in them again. For solar and wind you leave the windmills/panels in place and let the sun do its thing. For hydro you let the weather keep replenishing your river. For geothermal you dig a hole and the Earth will keep you warm. For biofuels you keep growing crops on the same fields year after year. The distinction is one of logistics; it has nothing to do with whether some energy source is "good" or bad. You can seriously reduce the need for mining uranium by reprocessing like the French do and the Japanese, much to the annoyance of their neighbors, are about to do. The two reasons the US doesn't is because first Carter banned reprocessing because he was worried about workers being lured by the Indians and Israelis into giving them fissionable materials and later Reagan unbanned it but went all Free-market so there's no subsidies.
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# ? Jun 9, 2013 20:13 |
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LP97S posted:You can seriously reduce the need for mining uranium by reprocessing like the French do and the Japanese, much to the annoyance of their neighbors, are about to do. The two reasons the US doesn't is because first Carter banned reprocessing because he was worried about workers being lured by the Indians and Israelis into giving them fissionable materials and later Reagan unbanned it but went all Free-market so there's no subsidies. http://web.mit.edu/newsoffice/2012/rare-earth-alternative-energy-0409.html Wind power relies on vast amounts of rare earth metals (over half a ton per turbine). Electric cars with lithium batteries would need vast amounts of Li and batteries also tend to fail (current Li-ion batteries lose half of their maximum capacity in 3 years - obviously we can do better than that, but we'd still need to replace batteries regularly). PV Solar cells (current ones) need to be replaced every other decade and don't really get recycled as far as I know. So... we can't simply assume "renewable energy sources won't run out" and would need extremely good recycling to be able to say "we can use renewable energy for effectively indefinite amounts of time". Since we're talking about future developments anyway... Let me re-introduce the Integral Fast Reactor with which, using pyroprocessing we would only need a small amount of mined uranium to start up each reactor and could reprocess existing nuclear waste to satisfy the current electricity demand for a couple of centuries . Let's go and recycle nuclear fuel very well, too
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# ? Jun 10, 2013 00:18 |
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hobbesmaster posted:You have to dig uranium (and fossil fuels) out of the ground and cart it to a reactor. Individual mines can be depleted and will not have uranium in them again. For solar and wind you leave the windmills/panels in place and let the sun do its thing. For hydro you let the weather keep replenishing your river. For geothermal you dig a hole and the Earth will keep you warm. For biofuels you keep growing crops on the same fields year after year. The distinction is one of logistics; it has nothing to do with whether some energy source is "good" or bad. No, it has to do with the amount of time a fuel source can sustain us and the consequences that exploiting it will have. I completely agree that eventually we will suck every last (economically extractable) molecule of uranium out of the earth, the ocean, etc. My point is precisely that, in fact: there is no such thing as a truly renewable energy source, eventually the sun will burn down, or swallow the earth, or the earth's core will cool, or the 0.1% loss in a 99.9% effective recycling process adds up and we run out of rare earth deposits or all our phosphate washes into the ocean. Those power sources may sustain us for a really long period of time, but they hold no inherent advantage over other energy sources that will also last for millennia like nuclear power. By that point we will have either figured out fusion or left our planet or extincted ourselves. There is no practical reason to prefer an unreliable, more expensive power source with millions of years of supply over a cheaper, reliable one with ten thousand years of supply. The much bigger concern at that point would be that our increasing energy usage is poisoning us with waste heat. So far humanity has managed to hold per-capita energy consumption constant for a while now, but there are a lot of people coming out of poverty in the developing world and Jevon's paradox suggests that cheap limitless energy would lead to increased usage. Vacuum is a good insulator and we can't exactly drop a huge ice cube in the ocean like Futurama. All the energy we produce is ultimately turned into heat. silence_kit posted:I am not the world's biggest thermodynamics buff, but I think your "meaningful question" may better be rephrased "can we break the second law of thermodynamics?" Most people tend to believe in the second law of thermodynamics. . . Apparently not the biggest literature buff either. http://filer.case.edu/dts8/thelastq.htm Paul MaudDib fucked around with this message at 00:52 on Jun 10, 2013 |
# ? Jun 10, 2013 00:30 |
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Paul MaudDib posted:Now, the more meaningful question. How can the net amount of entropy in the universe be massively decreased? There is as yet insufficient data for a meaningful answer. Let there be light, Doctor Asimov.
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# ? Jun 10, 2013 06:09 |
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Current worst-case nuclear plant construction, riddled with cost overruns and delays, versus current best case large-scale solar construction, with heightened momentum from the flood of cheap solar panels from the Chinese market. Who do you think wins? It's still nuclear, by a huge margin.quote:Germany’s solar program will generate electricity at quadruple the cost of one of the most expensive nuclear power plants in the world, according to a new Breakthrough Institute analysis, raising serious questions about a renewable energy strategy widely heralded as a global model. The authors took a lot of flak for their findings, being accused of cherry-picking and so on. So they later responded with another article explaining how they got their numbers and why they picked the German solar program and the Finnish EPR for comparison: http://thebreakthrough.org/index.php/voices/michael-shellenberger-and-ted-nordhaus/no-solar-way-around-it/ The two articles are worth reading.
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# ? Jun 11, 2013 16:32 |
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Here's one article that details the loss of greenspace to solar/wind.quote:The vastly underappreciated impact of renewable energy installations on the natural world is what originally drew the MCC into this fray. Installing just a couple dozen wind turbines on Western Maryland mountain ridges erased 120 acres of forest and moved 400,000 cubic yards of rock and topsoil, in addition to threatening migrating birds and bats. That's coming from an environmental group that had, 40 years ago, protested the hell out of the new nuclear plants being built. Haven't seen too many greenspace cost numbers for wind yet, so that's neat.
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# ? Jun 13, 2013 18:22 |
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Coincidentally I just heard an ad on the radio for a new environmental documentary called "Pandora's Promise", seems that some greenies are reconsidering the deady atom.
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# ? Jun 13, 2013 19:34 |
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Pander posted:Here's one article that details the loss of greenspace to solar/wind. I really hope everyone pulls their heads out of the sand and comes to the conclusion that fission is the right choice if they really care about the planet.
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# ? Jun 13, 2013 19:44 |
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PhazonLink posted:Coincidentally I just heard an ad on the radio for a new environmental documentary called "Pandora's Promise", seems that some greenies are reconsidering the deady atom. American Nuclear Society (I'm a member) is asking members to pimp the poo poo out of the movie. Pretty interesting reviews, I'm hoping to catch it but I worry it'll have limited release.
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# ? Jun 13, 2013 20:08 |
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Yeah, it needs to come out on iTunes/Amazon or even DVD. I can't get to any of the showings.
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# ? Jun 14, 2013 00:06 |
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Sinestro posted:Yeah, it needs to come out on iTunes/Amazon or even DVD. I can't get to any of the showings. A movie like this just needs to be released for free IMHO, in the interest of public education.
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# ? Jun 15, 2013 09:43 |
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Some good news on this front, it seems. IEA: Renewables to be 25% of global energy mix by 2018
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# ? Jun 27, 2013 00:30 |
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Gizmodo article on the benefits of using Thorium oxides to eat up all of the plutonium waste generated by nuclear plants. Nice read.
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# ? Jul 3, 2013 17:39 |
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Pander posted:Gizmodo article on the benefits of using Thorium oxides to eat up all of the plutonium waste generated by nuclear plants. Nice read. I just have to correct a few things in there: quote:Luckily, thorium (Th232) is an abundant—albeit slightly radioactive—element. It's estimated to be four times as common as uranium and 500 times as much as Here's a link to their official site http://www.thorenergy.no/ Interest really ramped up after these simulations were published: http://www.hindawi.com/journals/stni/2013/867561/ I think this is really cool for several reasons. For starters, it's a fuel matrix that can be used in existing light water reactors and heavy water reactors with relatively small adjustments. It's miles ahead from uranium-based MOX fuels, in that it's much cheaper to fabricate and capable of achieving near-complete plutonium burnup without any serious increases in positive feedback, thanks to thorium-232's nicer temperament when it comes to freshly-emitted neutrons compared to U-238 which likes to undergo energetic fission in those conditions. Thorium itself is ridiculously easy to obtain. It's practically free from heavy-rare earth deposits like Monazite sands, and even without concentrated sources it can be extracted from absolute sources like igneous rock for almost nothing.
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# ? Jul 4, 2013 01:05 |
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Every time I read about thorium it basically sounds like magic bullet technology. I've watched the thorium remix, and I'm pretty familiar with the ability to use it in CANDUs or new molten salt reactors. Now it can be used as a solid fuel in more typical boiling water reactors? I feel like the other shoe has to drop at some point.
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# ? Jul 4, 2013 01:29 |
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Kafka Esq. posted:Every time I read about thorium it basically sounds like magic bullet technology. I've watched the thorium remix, and I'm pretty familiar with the ability to use it in CANDUs or new molten salt reactors. Now it can be used as a solid fuel in more typical boiling water reactors? I feel like the other shoe has to drop at some point. The "other shoe" is that the Thorium cycle produces U-232, which makes reprocessing loving awful and decays into products which get more dangerous as time goes. This is one of the things that makes the Thorium cycle attractive, "extremely toxic" can also be read as "difficult to proliferate".
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# ? Jul 4, 2013 01:37 |
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Kafka Esq. posted:Every time I read about thorium it basically sounds like magic bullet technology. I've watched the thorium remix, and I'm pretty familiar with the ability to use it in CANDUs or new molten salt reactors. Now it can be used as a solid fuel in more typical boiling water reactors? I feel like the other shoe has to drop at some point. The only magic that I'm familiar with when it comes to thorium reactors is that thorium is cheap to obtain, so you're driving down the cost of fuel. Nuclear fuel is a tiny fraction of the cost of nuclear energy, though, and no one is excited to build nuclear reactors in the US, so it's all just a non-starter
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# ? Jul 4, 2013 12:34 |
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Alternative energy, be it solar, nuclear, wind, or whatever has always been fascinating to me but I know surprisingly little about it for how much it interests me. What books would you guys recommend for a scientific minded person with little background to the area?
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# ? Jul 4, 2013 13:48 |
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Quandary posted:Alternative energy, be it solar, nuclear, wind, or whatever has always been fascinating to me but I know surprisingly little about it for how much it interests me. What books would you guys recommend for a scientific minded person with little background to the area? I havn't read it yet but Richard Muller's Energy for Future Presidents is on the list of books to read. http://www.amazon.com/gp/product/0393081613/
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# ? Jul 5, 2013 10:43 |
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Paul MaudDib posted:The "other shoe" is that the Thorium cycle produces U-232, which makes reprocessing loving awful and decays into products which get more dangerous as time goes. This is one of the things that makes the Thorium cycle attractive, "extremely toxic" can also be read as "difficult to proliferate". Does this stuff have to be held to higher storage standards than the already impossible store waste we produce?
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# ? Jul 5, 2013 12:18 |
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QuarkJets posted:The only magic that I'm familiar with when it comes to thorium reactors is that thorium is cheap to obtain, so you're driving down the cost of fuel. Nuclear fuel is a tiny fraction of the cost of nuclear energy, though, and no one is excited to build nuclear reactors in the US, so it's all just a non-starter Also, like Paul MaudDib said, it has a favorable fuel cycle, for certain definitions of favorable.
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# ? Jul 5, 2013 15:50 |
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Nevvy Z posted:Does this stuff have to be held to higher storage standards than the already impossible store waste we produce? U-232 has a ridiculously large fission cross-section, so it is easily destroyed in any given nuclear reactor. With thorium MOX, U-232 is created as it's being destroyed up until it reaches equilibrium at a concentration of 0.4% (http://www.princeton.edu/sgs/publications/sgs/pdf/9_1kang.pdf). If you happen to have an excess of U-233 fuel with U-232 you need to get rid of for any reason, you can just throw it in a non-thorium using system and fission it completely. That said, if you ever decide to shut down a nuclear reactor and brush U-233 fuel contaminated with U-232 under the carpet for 40 years hoping people forget about it, leaving the fuel on-site in a chemical form that evolves fluorine, then expect cleanup and disposal of the resulting mess to cost around half a billion USD: http://energy.gov/ig/downloads/audit-report-ig-0834 More detail: http://energy.gov/nepa/downloads/ea-1488-environmental-assessment-u-233-disposition-medical-isotope-production-and Nuclear does not misbehave when it's treated properly. If only states would just treat it properly.
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# ? Jul 5, 2013 18:25 |
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Sydney is launching a plan to overhaul our energy supply, if anyone is interested there's a detailed 118 page plan here: http://www.cityofsydney.nsw.gov.au/vision/on-exhibition/current-exhibitions/details/renewable-energy-master-plan website: http://www.cityofsydney.nsw.gov.au/vision/sustainability/energy/renewable-energy They talk about 100% renewable, but reading through the plan they only seem to aiming for 30% renewable, and most of that comes from swapping natural gas for renewable gas, which seems to be collected from wastes (agricultural, landfill, etc). They aim to get the bulk of it from within the bounds of the city, through roof mounted installations (PV, solar thermal hot water, and micro wind turbines on buildings over 30 stories high), and tri generation plants inside buildings, which seems like a good way to reduce transmission losses. They also mention a bit of ocean and tidal, and there's a good list of case studies of renewable installations around the world at the end. Anyway it's a pretty good crack, lots of graphs and maps and figures, thought it might be of interest to people here. Critical eyes are always good. They're presenting it at town hall on Monday night, I'm planning on going. Any Syd goons up for it? Quantum Mechanic? In other news, a gas company has announced a $450 million solar PV farm in rural NSW: http://www.smh.com.au/business/carbon-economy/agl-unveils-australias-biggest-solar-energy-plants-20130731-2qy10.html 150 MW, 375 Hectares, 50% government funded, 450 jobs during construction, expected to produce 360,000 megawatt-hours of electricity annually. I'd prefer they put a solar thermal plant there personally, but hey, should be a good boost for the industry, and a step in the right direction I suppose.
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# ? Aug 1, 2013 02:47 |
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Unfortunately Mondays are no good for me, since I finish work at 7 and it'd take me about 40 min to get to Town Hall. It looks really interesting though.
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# ? Aug 1, 2013 22:14 |
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Hobo Erotica posted:Sydney is launching a plan to overhaul our energy supply, if anyone is interested there's a detailed 118 page plan here: It is, like any renewable energy proposal I guess, quite optimistic. I'll just comment on things I actually know something about so they could be right on the rest. Building windmills within the city limits sounds awful, they make so much noise. The case study says it's not a problem because the city also makes noise, excellent! Estimating offshore wind capacity factor at 40% is laughable. German offshore wind farms do 17% and it's not because they're technically incompetent. poo poo breaks, offshore poo poo breaks more often and takes a lot longer to fix. In Germany they also have a lot of trouble with the effects of windy at night / not windy during the day combo so unless you have some nearby hydro power to offload excess energy this may be a problem as well. Mini turbines on high buildings are window dressing, they amount to absolutely nothing. The case study mentions a building with 19 kW nominal capacity, lol. Tidal / wave power is a pipe dream and I think it'll stay that way forever. It's just too expensive to build and maintain rotating equipment under water for the relatively small amount of energy you get from it. Also you slow down the earth's rotation (not really)
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# ? Aug 1, 2013 23:26 |
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Pvt Dancer posted:Tidal / wave power is a pipe dream and I think it'll stay that way forever. It's just too expensive to build and maintain rotating equipment under water for the relatively small amount of energy you get from it. Also you slow down the earth's rotation (not really) But but.... the PDF says the potential capacity is 20% of the entire countries energy needs from non-tidal energy. How
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# ? Aug 2, 2013 02:31 |
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So, this is a scam, right? http://oilprice.com/Energy/Energy-General/Governments-get-Excited-by-Hydro-Nano-Gas-which-Eliminates-all-Carbon-Emissions.html quote:HydroInfra Technologies, based in Sweden, claims to have developed the answer to greenhouse gases and fossil fuel emissions, stating that their Hydro Nano Gas (HNG) “instantly neutralises carbon fuel pollution emissions.” I can't tell what they're claiming to be able to do, but it has something to do with "Exotic hydrogen" and uh, causes diesel to burn a hundred degrees hotter and clean or something. Interestingly they've gone out of their way to document their experimental setup: http://www.hydroinfra.com/en/wp-content/uploads/sites/2/2013/06/HIT-VerifReport-draft7-130710.pdf Anyone familiar enough with this kind of analysis to say something about whether this is prima facie garbage?
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# ? Aug 2, 2013 18:46 |
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Paper Mac posted:So, this is a scam, right? "“According to our professional experience we have never seen results like this before” – joint comment by Lars Månsson and Olof Sten" Indeed I've never seen such a scammy slide in my professional experience either. Slide 2 is hilarious in all ways.
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# ? Aug 2, 2013 19:01 |
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Yeah, I think they're claiming to be able to violate conservation of mass (with muons!!!) or something. I was surprised that there are consultants who presumably have professional reputations to protect that would consent to being photographed anywhere near an experimental apparatus that is supposed to poof CO2 into a pocket dimension or something, though.
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# ? Aug 2, 2013 19:26 |
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Paper Mac posted:So, this is a scam, right? Well, they don't really say what the technology is, but they describe it as a scrubber. Their presentation doesn't say they eliminate carbon dioxide, only carbon monoxide. They say the CO2 is removed in a later scrubbing step. In fact, their test results on slide 3 shows CO2 emission going up from 6.0% to 8.0%. Also on page three, at the top: quote:The HNG-scrubber system consist of three phases: So it appears to be a system for reducing powerplant emissions overall, not that they can magically remove carbon dioxide from a flame. It seems a bit overblown, and may suffer from translation into English. It doesn't seem to be a scam, just overhyped. The best I can figure out is that it's a form of water injection, perhaps with gaseous oxygen and hydrogen in it, either dissolved or as small bubbles.
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# ? Aug 2, 2013 19:45 |
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# ? May 10, 2024 01:09 |
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Deteriorata posted:Well, they don't really say what the technology is, but they describe it as a scrubber. Their presentation doesn't say they eliminate carbon dioxide, only carbon monoxide. They say the CO2 is removed in a later scrubbing step. In fact, their test results on slide 3 shows CO2 emission going up from 6.0% to 8.0%. quote:What is HydroNano Gas? Nope it's a scam.
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# ? Aug 2, 2013 19:51 |