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redshirt posted:I've never heard such a thing was possible - that a loop of coil ten feet below the ground will somehow reduce overall ground temperature if everyone was doing it. Seems highly unlikely to me - got anything I can read on the subject? It would be a temporary, local thing - too many houses in an area extracting heat could pull it out faster than it could flow back in from elsewhere. This would lead to a reduction in the local ground temperature and lower the efficiency of the process. Inversely, in the summer there would be too much heat injected, leading to an anomalously high ground temperature and lowered air conditioning efficiency. I have no idea what the thermal conductivity is of the ground and whether or not it's a valid concern. It would probably be a bigger problem in some places than others.
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Mar 26, 2013 20:25
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karthun posted:So you have provided me air conditioning during the sub zero Minnesota winter. Well done sir. All of that money you spent for me to cool my house down during winter is well spent, much better then say silly things like insulation or more efficient heaters. Wait here is an idea, we can just rip out ALL of the insulation in my home. That way it will be MORE efficient at cooling my house down during winter! http://en.wikipedia.org/wiki/Geothermal_heat_pump You can move heat from a colder source to a warmer one with the input of energy. It's how a heat pump or air conditioner works. It's not direct geothermal heating, it's using the ground as a constant-temperature heat sink in both winter and summer.
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Mar 26, 2013 21:05
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karthun posted:Its not heating or cooling nor hot or cold air, it is 55 degrees. 55 degrees is not warm enough to prevent hypothermia so you need to heat it to a reasonable temperature. It's the same principle as how your air conditioner will take 100°F air outside your house and generate 72°F air inside your house. It's moving heat from inside your house to the air outside your house by way of a Carnot cycle. A heat pump extracts heat from the cold air outside to put it into your house - the reverse of an air conditioner. What we're talking about here is the exact same thing, except the heat sink is the ground instead of the air. You're stuck on thinking it's just pumping water through tubes. That's only part of it.
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Mar 26, 2013 21:59
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karthun posted:An air conditioner doesn't take 100 degree air from outside your house, it takes 76 degree air inside your house and cools it down 60 degrees. Which it does via a Carnot cycle, taking heat from the 76° air inside your house and transferring it to the 100° air outside the house, discharging 60° air back into your house. This is not something that happens spontaneously, hence electrical energy is required to make the process work. Ground-sourced heat pumps extract heat from 55° water and use it to heat the house, discharging colder water back into the ground to be rewarmed by the Earth. Again, a Carnot cycle is used along with electrical energy to make this otherwise non-spontaneous process happen.
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Mar 26, 2013 22:15
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karthun posted:No, ground-sources heat pumps extract heat from the 65 degree air intake, inside the house, and use to to warm the 55 degree water. That would be great if I wanted water and air at 55ish degrees. Instead now I have to heat that air 20 degrees, from 55 to 75 instead of heating it from 65 to 75. I don't know if you're trolling or deliberately dense or what. A ground-source heat pump extracts heat from 55° water and uses that heat to warm the air in your house. It discharges water that is colder than 55° back into the ground. It is colder because it has had heat extracted from it. It is obviously not a spontaneous process, as heat spontaneously flows from hot to cold. Energy is required to overcome this, which is why a Carnot cycle is used to make it work.
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Mar 26, 2013 22:39
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spankmeister posted:Please say they hinder them because gently caress coal. I think the price of natural gas (being far cheaper than coal at the moment) has a far bigger impact than any regulations.
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Mar 26, 2013 23:07
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Install Gentoo posted:The sun isn't there at night, and we haven't gotten good solutions to actually store our solar energy yet. I was under the impression that thermal energy could be stored pretty well as molten salts, particularly hydrates that melt just above room temperature. The issue has been primarily one of demand, that there wasn't much of an incentive at this point to refine it into a commercial product. Part of the heating system would be a series of pipes, filled with these salts. Excess heat would melt them during the day, then they would give off the heat as they resolidified during the night. They'd be essentially maintenance free and last for decades.
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Apr 1, 2013 05:55
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CombatInformatiker posted:Since there are a lot of nuclear fission proponents in this thread, could you give me some pointers/links to how the highly radioactive waste products can be safely stored/treated? Not trying to argue, just genuinely interested, and I didn't find the answers on Wikipedia (nor in this thread). The general idea is to take long-lived isotopes and put them back into a reactor, where they can be bombarded with neutrons and converted to much shorter-lived isotopes. The problem is that short half-life means it's intensely radioactive - but not for very long. The intensely radioactive waste then rapidly decays into something relatively stable and easy to handle. Right now, we've got tons of relatively low-level waste that will remain radioactive for tens of thousands of years. It's going to be a problem for that long. We need to find something to do with it other than just sit around and look at it and worry about it. As far as long term disposal, the best suggestions I've seen are using them to make a form of glass - not encasing them in glass, literally making glass with them. The radioactive atoms won't easily leach out, it won't flow, it won't decay - it will just sit there, almost forever. They could be buried someplace where plate tectonics will eventually recycle them back into the mantle of the Earth.
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Apr 2, 2013 14:56
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rudatron posted:The paper reinforces the main issue with renewables, that 'nameplate' (theoretical maximum) capacity has to be much higher than actual delivered capacity with renewables, then it does with fuel-based energy such as uranium or fossils. Even then, they end up using biogas to make up for shortfalls that occur at the wrong times. I'm not convinced that giving up farmland for biofuels is a good idea, in a future where arable land falls: Over-building renewable generating capacity isn't necessarily a waste of money. The excess capacity could always be used to make hydrogen from water when favorable conditions result in more generation than is needed.
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May 8, 2013 18:03
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CombatInformatiker posted:Andrea Rossi's E-Cat might not be a scam after all I find it disturbing that they make no effort to describe any changes to the material in the tube. The entire paper is about energy analysis. What's actually going on in the tube is more important than anything else, as their procedure may be laughably inefficient once we know what's driving it. All they say is that it's a mixture of nickel and hydrogen, with no effort to isolate or identify any reaction products after it's done. That they show no interest in demonstrating what's actually going on still makes it smell of scam to me. Deteriorata fucked around with this message at 14:44 on May 24, 2013 |
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May 24, 2013 14:41
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Herv posted:Someone listed this as a source of unlimited clean energy on a fission discussion. How is it "unlimited free energy"? It operates on a temperature differential like any other heat engine. You have to supply the heat to the hot side of it. They describe it as free energy because it can use small temperature differentials that would otherwise be waste heat. It makes perfect sense that "there's no money in it", because it probably costs more to run than it's worth.
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May 24, 2013 20:32
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CombatInformatiker posted:You didn't understand the purpose of this experiment. It wasn't about "demonstrating cold fusion/LENR/whatever", it was about showing that the device outputs more power than it can conceivably store using chemical fuels. Assuming they made no errors during measurement, it was a full success. Until we know what's in the tube and what sort of reactions are happening, it's not a demonstration of anything. It could be (and probably is) an elaborate con. If he wants to be taken seriously, he needs to describe the entire system, inside and out, in a way that someone else in another lab could set it up and do it. It isn't "science" if no one can reproduce your results.
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May 25, 2013 14:43
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CombatInformatiker posted:Fun fact: physical processes can be reality even if we don't understand what is happening. No one knowing what happens exactly inside the device does not, by itself, imply it being a scam. If the measurements from the experiment are correct (and if the experiment has not been tampered with), then it is not a scam. One way to ensure it is not a scam is to tell us what's going on inside, so that everything is on the up and up. I am disinclined to believe his energy measurements due to his evasiveness. There very well may be extra wires or pipes, for example, that we don't know about and are hidden in the pictures that are actually supplying the supposed extra energy. His energy measurements appear to show energy being generated above what appears to be energy input, but there is no way of verifying if it's legitimate without more information.
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May 25, 2013 16:27
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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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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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GreyjoyBastard posted:It's mostly concerned with things that aren't the safety questions. That said, the nice thing about hydrofracture drilling is that, in theory, it is safe and (fairly) clean, as long as you cut absolutely no corners and have a really thorough, conscientious geological survey. Yeah, a lot of the issues with fracking are the same issues with drilling gas wells generally. It's just that in the past it's generally gone on far away from civilization so nobody noticed or cared. Fracking makes it possible to exploit a lot of deposits that were unprofitable previously. Many of those sites are now, unfortunately, underneath places where people live.
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May 14, 2014 21:08
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Negative Entropy posted:This was already stated in the climate theead but piezoelectric roadways can also be used, and since they lie under the road maintenance for them shouldn't be too bad. Energy-generating roadways appear to be an idea just gaining ground so it should be given a go in testing before it gets thrown out as another fad tech. The biggest problem is that most roads are lightly traveled and far from civilization. Anything valuable is going to get stolen in fairly short order. Stuff as cheap and useless as road signs are stolen regularly for their novelty or scrap value. I can't imagine anything of any value that isn't set in six feet of concrete is going to last very long.
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May 27, 2014 00:29
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The main reason nuclear gets discussed so much is that it's complicated and interesting, with a wealth of possible technologies to compare. For technology geeks, that's fun to talk about. Other electric generating technologies are pretty boring and staid by comparison. Solar is the closest competitor, but even then, "breakthrough" advancements are about getting another 0.1% of conversion efficiency. Solar highways got bashed because it's a dumb idea from any standpoint. There's just not a lot to talk about with technologies other than nuclear most of the time. New developments in other fields get discussed as they come up.
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Jun 18, 2014 02:13
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Ardennes posted:Someone dismissing green technologies one by one is probably anti-green. The only thing I've seen even close to this is people arguing against zealots who insist the entire electric generation load can be carried by solar and wind. This is not mathematically possible. Carbon-free electricity generation has to include a fair amount of nuclear. We should certainly exploit solar and wind sources as much as possible, but nuclear has to be in there as well.
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Jul 8, 2014 15:46
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Ardennes posted:I like how some of that jargon like "persecuted minority" leaks out a bit. I am pretty clear in my position, there has been a pro-nuclear/anti-green group of posters in this thread that probably should be acknowledged as actually existing. Why does this even matter? It's an internet discussion thread that's had lots of contributors. "Acknowledged as actually existing" doesn't make any difference as to whether their arguments are salient or stupid.
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Jul 8, 2014 16:31
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Pander posted:Interesting read. I was a bit skeptical at first, trying to determine if anything mentioned had been peer reviewed, but some of the follow-on links appear legit and make for good reading (the Dutch analysis of the Fort Worth drill site is accessible and informative). That's pretty much the way it is with all resource extraction, though. The easiest/cheapest to mine stuff comes out first, then the more expensive as the price of the material rises. I guess the question is about how steep the curve is - how much is available at various price points and whether the gas boom can sustain itself. If gas can wean us off coal, then that leads to even better technologies, it's a good thing. If the end of the gas boom means a return to coal, then it was pointless.
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Jul 8, 2014 19:24
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Ardennes posted:The "random numbers" are from a literal direct quote from you. I find it really creepy you refuse to acknowledge that. You can say you didn't mean it or it was a joke or something that didn't represent your position, but you certainly can not pretend I made that quote up. The "bashing" is against people out of touch with reality. "100% renewable" is not possible given current technology. It may be possible at some point in the future, but arguing for that right now only demonstrates that the poster has no grasp of reality. I'd be all for 100% renewables if it was possible. Nearly everybody would. Nuclear isn't an end in itself, but a means to an end - meeting the world's electricity demands without burning fossil fuels. When people post dumb, poorly thought-out, unrealistic stuff they get jumped on, and, yes, "bashed." That happens in any thread devoted to realistic, scientificly-based analysis of a problem. You seem to be reading into this thread far more than actually exists.
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Jul 9, 2014 20:57
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Sheikh Djibouti posted:The technology doesn't involve cells but a very thin film (nanometers to micrometers, as I understand it), so it's not really a matter of strapping on cells. I guess if you were in an area that otherwise had light obstructions (trees or otherwise) they would indeed be impractical, though. I used to work in Midtown Manhattan, where other buildings would be the issue, but even there there was quite a lot of exposure. As to appearance, I never had the sense that they would substantially affect appearance beyond adding tinting, so I'd be surprised by an aesthetic issue. If you're correct that they're "quite expensive" that likely is a key reason (combined with impracticality depending on location and exposures) why they haven't gone anywhere, and that was certainly an issue in the early 90s. Not a big deal, I was just curious about what become of that technology. I think the problem was that in real-life application, they were far too expensive and fussy to be practical. They could set up lab conditions that made them seem great, but were sufficiently fragile and costly to make them unattractive to actual buyers. There are still reports cropping up occasionally of breakthroughs of one sort or another with assurances that this time they'll actually be affordable and useful, but not much has ever made it to market.
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Jul 10, 2014 03:25
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Nevvy Z posted:In the long long run is it theoretically possible to replace peaking with battery and or turning down desalination? Sure, there's lots of different ways of handling peaking. Ones that are cheap and publicly acceptable are fairly rare, unfortunately. The current (no pun intended) problem with batteries is that they are hugely expensive to build at the scale needed for effective peaking, and also expensive to maintain. Desalination is not currently practiced on a wide enough scale to make a difference, but is definitely something that would be done at off-peak hours to consume excess base generation when electricity is cheap and available, since it's not done as-needed to meet immediate demand.
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Jul 11, 2014 15:11
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Farmer Crack-rear end posted:Given the tremendous expense of grid-scale energy storage, what about going the other way for dealing with peaking? In other words build out capacity to the point where you'll always have enough, and then when demand falls below peak, have at least a portion of power generation capacity feeding into something non-crucial (like cracking water for hydrogen, or even just giant electric radiators if necessary), and then be able to switch that low-priority load off instantly in order to meet surges in demand. That gets rather difficult to make work politically. Power plants consume huge amounts of capital, and it's hard to justify investment in capacity you don't actually need when there's so many other things that money could be spent on. Building a power plant specifically to crack water into hydrogen would have to be justified on its own merits.
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Jul 11, 2014 23:06
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Yeah, I've usually seen it in reference to stuff like people installing photovoltaics on their roofs and selling excess power back to the grid, or a neighborhood setting up a biomass generator powered by grass clippings and tree limbs and such. A lot of it seemed impractical and kind of silly, but didn't seem to be anything actually wrong with it. It's just not the panacea some seem to claim. Small-scale local power generation will certainly help, but probably not a lot.
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Jul 14, 2014 23:11
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Nintendo Kid posted:Your house's measly couple kilowatts of usage at peak are a drop in the bucket to the power going through the grid, you are not saving anyone much of anything in terms of transmission loss by having some solar panels. Come on, you're both right. Decentralization would indeed save on transmission losses, it's just very unlikely that those savings would actually make any difference.
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Jul 16, 2014 05:54
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EoRaptor posted:So MIT just announced this, a carbon foam and graphite floating layer that can transfer solar energy to water in a reasonably efficient manner. The water vapor doesn't block the sunlight, it blocks further evaporation of the water. You get a liquid-vapor equilibrium established pretty quickly above the foam, so you have to keep pulling the vapor off so it can be replaced by more from the evaporating liquid.
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Jul 22, 2014 16:36
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A big flaming stink posted:i'm not saying 'what should we wave a magic wand over' as much as 'what should we strive for.' just taking the political environment as an unshakable fait accompli seems like giving up the war before the first battle is fought. It might help to include an alternative solution that includes nuclear, so people can judge just how squeamish they are about it. They may oppose nuclear in the abstract, but seeing the actual price to be paid for no nukes may change some opinions.
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Aug 4, 2014 05:03
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Frogmanv2 posted:Why? Probably for evacuation in case of a fire.
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Aug 9, 2014 17:14
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hydroceramics posted:I have a question about energy storage: is there a reason besides cost that we're still using batteries over capacitors? From a layman's wiki-ing, they seem like a much better technology. From Wiki: quote:As of 2013 commercial specific energies range from around 0.5 to 15 Wh/kg. For comparison, an aluminum electrolytic capacitor stores typically 0.01 to 0.3 Wh/kg, while a conventional lead-acid battery stores typically 30 to 40 Wh/kg and modern lithium-ion batteries 100 to 265 Wh/kg. Supercapacitors can therefore store 10 to 100 times more energy than electrolytic capacitors, but only one tenth as much as batteries. Batteries still beat the crap out of capacitors in terms of energy stored per kg.
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Oct 31, 2014 23:26
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Nintendo Kid posted:There were also simply a lot of people, many of them normally quite smart, who completely misunderstood what the term "peak oil" was supposed to mean. Thus they thought that peaking oil production for a year would mean there was no oil left afterwards, instead of it meaning that production would decline. To add to this, remember that there is still gobs and gobs of oil in the ground in all those places. While extracting it was too expensive with oil at $20/barrel, it becomes viable at higher price points. Oil will be available for quite a while. So what has "peaked" is cheap oil. As long as there is demand for it at a sufficient price, there will be plenty for a long time.
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Nov 1, 2014 17:41
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When I learned German, we were taught those names for the elements. Carbon was Kohlenstoff, Hydrogen was Wasserstoff, Oxygen was Sauerstoff, Lead was Plumbum, Tungsten was Wolfram, Potassium was Kalium, and so on (although the IUPAC symbols were used regardless). Perhaps conventions have changed in the decades since then, but I assumed every language had its own common names for the elements that differed from the English versions.
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Jan 29, 2015 17:10
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OwlFancier posted:Err, guessing that's nitrogen? "Dephlogisticated air" was Joseph Priestley's original term for what was later determined to be oxygen. It implied air that had all the phlogiston removed from it so that it essentially sucked the phlogiston out of materials, making them burn fiercely.
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Jan 29, 2015 19:03
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CommieGIR posted:Vermont Yankee was especially sad, as they are trumpeting it as a 'Success for Renewables' Biomass is a step up, actually. It contains carbon that was extracted from the atmosphere recently, so there is no net CO2 gain in burning it.
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Apr 28, 2015 16:04
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CommieGIR posted:It all depends on what you are burning: Coal and oil are 100% carbon that has been sequestered from the atmosphere for millions of years. Whatever the objections of that blog are, biomass represents a vast improvement over them.
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Apr 28, 2015 16:31
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hobbesmaster posted:And trees are carbon that has been sequestered from the atmosphere for decades. That is indeed an improvement but it doesn't seem worth it. Those trees would die and rot eventually anyway, and their carbon returned to the atmosphere in the near term regardless. Burning biomass is significantly better than burning fossil fuels. No hand-waving will change that.
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Apr 28, 2015 16:36
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hobbesmaster posted:Unless they would have lived for decades longer and taken years to decompose instead of a few minutes. Its still releasing more carbon into the atmosphere and yes its better than natural gas but we have energy sources that can be pursued that do not release carbon dioxide and biomass should not be put into the same category as them. I'm not putting them in the same category as the others. What I objected to was lumping biomass with coal as being equally bad. We need to avoid letting the perfect be the enemy of the good. Replacing nuclear with biomass is a small step backward, but nowhere near as bad as burning coal. Replacing coal with biomass would be a significant step forward in net CO2 emissions. I'm in favor of making progress in the right direction.
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Apr 28, 2015 16:43
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Phanatic posted:Coal is. Oil's not. That's why burning natural gas is a shitload cleaner than burning coal, you're burning 4 hydrogens for every carbon. I'm aware of that. The carbon in the oil is what has been sequestered for millions of years.
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Apr 28, 2015 17:09
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StabbinHobo posted:y'know the funny thing is, given what we know now about what lead did to the baby boomers, it seems not just reasonable but a total given that coal power is causing something at least as bad as autism The lead thing is largely a fallacy. It's the standard "correlation does not equal causation" problem. A whole lot of things happened in society at about the same time lead was coming out of gasoline, so the probability that lead had anything to do with it is quite low. Crime is well known to be a complex problem with a multitude of overlapping causes. Claiming it can be almost completely explained with one variable is kind of silly.
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May 12, 2015 00:50
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