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Post by apophys on Jul 10, 2017 5:21:09 GMT
Fossil fuel power would need to release 0 net CO2 into the atmosphere, but could concievably landfill pure carbon dust or something. That last one in particular might not produce net energy, but that's a failing of the power source. A probably better example here would be to feed waste emissions into a greenhouse in such a manner that no air escapes (which is synergistic, as plants very much appreciate a CO2-enriched atmosphere). Produce could be sold if garbage and sewage systems properly capture and deal with waste.
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Post by Pttg on Jul 10, 2017 5:56:45 GMT
Fossil fuel power would need to release 0 net CO2 into the atmosphere, but could conceivably landfill pure carbon dust or something. That last one in particular might not produce net energy, but that's a failing of the power source. A probably better example here would be to feed waste emissions into a greenhouse in such a manner that no air escapes (which is synergistic, as plants very much appreciate a CO2-enriched atmosphere). Produce could be sold if garbage and sewage systems properly capture and deal with waste. While I like the sentiment, there is no significant correlation to atmospheric CO2 to plant growth in this 16-year multivariable study. Also, US natural gas power alone released ~600 Mtons of CO2 in 2015; the USA grew 9 Mtons of rice. Assuming that the rice is 25% dry carbon (approximately correct for life) and that rice farming is representative of other fields, carbon sequestration to plant would require an operation 266 times the size of the US rice farming industry. Not counting the airtight greenhouses. More likely, such a legal structure would render oxidation-based power sources economically inefficient, which isn't the main goal, but is still good.
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Post by apophys on Jul 10, 2017 20:23:12 GMT
Not sure what's going on there. The first link in a google search gave me this: "Comprehensive reviews of the plant science literature indicate that a 300 part per million (ppm) increase in atmospheric carbon dioxide (CO2) concentration generally increases plant growth by approximately 30%. Working with two species of floating aquatic plants and three terrestrial species, we demonstrate that this stimulatory effect of atmospheric CO2 enrichment is strongly temperature dependent." www.sciencedirect.com/science/article/pii/0167880987900235I'm talking about controlled growing though, not about climate change simulation. "Tomato crops were grown in greenhouses with and without CO2 enrichment to approximately 900 vpm. Plants grown under enhanced CO2 concentrations flowered earlier and produced 30% more marketable fruit than those grown in normal air. [...] Such fundamental changes in photosynthetic behavior suggest that the effects of CO2 enrichment on yield are not only due to increased growth in the presence of additional photosynthetic substrate. They also result from changes in the innate capacity of photosynthetic systems to utilize CO2." www.nrcresearchpress.com/doi/abs/10.4141/cjps78-119"For the second winter crop, [...] At the standard nutrient level, unventilated houses yielded 64 and 63% greater than the control at 1000 and 1350 uL CO2/liter, respectively." pubag.nal.usda.gov/pubag/downloadPDF.xhtml?id=54636&content=PDFTotal US crop production plus pasture and harvested roughage is ~1.45 trillion pounds. ( css.umich.edu/sites/default/files/U.S._Food_System_Factsheet_CSS01-06.pdf) Which converts to 658 Mt (in metric tons). Assuming it's 25% dry carbon, and assuming CO2 enrichment boosts production 30% (with appropriate temperature management), emission capture could permanently sustain 49.35 Mt of extra carbon from fossil fuel burning. Which is 181 Mt of CO2, or 30% of current fossil fuel burning.
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Post by The Astronomer on Jul 11, 2017 16:49:14 GMT
Not sure what's going on there. The first link in a google search gave me this: "Comprehensive reviews of the plant science literature indicate that a 300 part per million (ppm) increase in atmospheric carbon dioxide (CO2) concentration generally increases plant growth by approximately 30%. Working with two species of floating aquatic plants and three terrestrial species, we demonstrate that this stimulatory effect of atmospheric CO2 enrichment is strongly temperature dependent." www.sciencedirect.com/science/article/pii/0167880987900235I'm talking about controlled growing though, not about climate change simulation. "Tomato crops were grown in greenhouses with and without CO2 enrichment to approximately 900 vpm. Plants grown under enhanced CO2 concentrations flowered earlier and produced 30% more marketable fruit than those grown in normal air. [...] Such fundamental changes in photosynthetic behavior suggest that the effects of CO2 enrichment on yield are not only due to increased growth in the presence of additional photosynthetic substrate. They also result from changes in the innate capacity of photosynthetic systems to utilize CO2." www.nrcresearchpress.com/doi/abs/10.4141/cjps78-119"For the second winter crop, [...] At the standard nutrient level, unventilated houses yielded 64 and 63% greater than the control at 1000 and 1350 uL CO2/liter, respectively." pubag.nal.usda.gov/pubag/downloadPDF.xhtml?id=54636&content=PDFTotal US crop production plus pasture and harvested roughage is ~1.45 trillion pounds. ( css.umich.edu/sites/default/files/U.S._Food_System_Factsheet_CSS01-06.pdf) Which converts to 658 Mt (in metric tons). Assuming it's 25% dry carbon, and assuming CO2 enrichment boosts production 30% (with appropriate temperature management), emission capture could permanently sustain 49.35 Mt of extra carbon from fossil fuel burning. Which is 181 Mt of CO2, or 30% of current fossil fuel burning. Dai 1: With more CO2 plants requires more water and nutrients. Dai 2: With more CO2 more insects come and eat plants. Dai 3: Please keep your CO2-rich atmosphere in your greenhouse.
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Post by Hicks on Jul 21, 2017 0:31:02 GMT
Neither methane snow nor meteor rain nor contraction heat nor solar flare nor gloom of tidally locked night stays these couriers from the swift completion of their appointed high density rounds.
We have the internet, we have radio transmission and we have plenty enough advanced cryptology to support it, yet we still use physical FIAT funds, require hand signature and every form in triplicate. Who said this'd be any different in the space age?
The idea is quite simple. What is the fastest, most reliable and most economically viable way of getting a standardized packet of high priority mail to and from the Moon? Other bodies would be a bigger nut to crack, so it's better to keep it simple and mostly three-body.
Would Lunar Post require specially designed containers/tugs for incoming parcels, or would they simply ship their mail along with passenger shuttles? Would it be faster to expedite high priority mail in dedicated containers launched on a free-return trajectory to be captured by either an orbital station or dropped into the ocean/mare? And how difficult would it be to ship from the largely equatorially inhabited Earth to one of the planned Moon habitats near its poles?
It's all dependent on infrastructure. But anything that couldn't be faxed will go by either mass driver or rocket and sorted by G tolerance, with the lowest tolerance being the most expensive. High G tolerance mail is loaded into a thruster/heatshield/parachute armature and fired by a mass driver from the earth to low lunar orbit and deorbited by the small chemical thruster. The unfurled cannister is repacked with return mail and fired by a mass driver into an extreamly low earth orbit, where the heat shield/parachute let it land in a designated pickup zone. Technically moon to earth mail is cheaper than the reverse, but will be limited to the number of canisters sent by terrestrial mass drivers. Rocket mail will be far more expensive, but will piggy-back on personal transfers from earth to the moon.
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Post by newageofpower on Sept 16, 2017 22:51:57 GMT
Large-scale (megajoule and above) power storage is virtually impossible unless you use ridiculous methods such as enormous superconducting magnetic energy storage installations or otherwise. Currently, basically all energy that gets pumped into the grid gets used immediately (in relativistic terms). There are many megawatts of energy being exchanged around any given national network every second - you cannot expect any battery to be able to have that much throughput without absurdly huge parallel arrangements. Current UHMWPE flywheels can store 2Mj/kg. If we go to like, graphene, diamondoid, or multi-wall CNT flywheels, you will exceed anything subnuclear in energy density... With vacuum bearings and sealing storage, we can reduce total energy losses below 5%, almost all of it in exchanging between kinetic and electrical energy.
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