| Energy For and From the Moon David Dietzler 2008 |
| It's predicted that the ITER(International Thermonuclear Experimental Reactor) will generate its first plasma in 2018 and by the 2030s the first commercial deuterium and tritium burning reactors will start up. He3 fusion is decades beyond that if ever. Since a kg. of He3 burned with 0.67 kg D yeilds 19 MW/years.....a ten or 20 ton miner like the ones designed by Kulcinski et al at the U of Wisconsion that produces 33 kg of he3 per year will get us 627 MW years or enough for a moderate sized powerplant. Eventually we will need to go beyond the old craft production model on the Moon and do mass production of these mining machines if we want to make enough miners to produce enough he3 to grab a large chunk of the energy market. Thing is, there will be intense competition with fossil fuels probably for the rest of this century, roof top solar panels and big desert solar panel farms, wave power, wind power, biogas from sewage, breeder reactors if "they" ever let us build them, and energy conservation thru architecture and more fuel efficient cars, even electric cars. While we are trying to squeeze blood out of a turnip on the Moon the whole world might go solar and breeder reactors. Right now the USA uses like one terrawatt year of electricity, so we need about 52,631 kg of helium 3 too supply all electrical demands and 1565 he3 miners or 15,650 to over 30,000 tons of these machines at 10 to 20 tons per mining machine. Then there is demand from the rest of the world and the fact that the USA will use more than 1 TW by the second half of this century. WE WILL NEED LARGE HE3 MINING TRACTORS FACTORIES ON THE MOON AND ASSEMBLY LINE MASS PRODUCTION. So the question is, how do we evolve this large scale industry on the Moon starting with a small operation and working our way up the learning curve??? NASA plans to launch two rockets per mission for a billion dollars apiece, twice a year, with stays lasting 2 weeks on the Moon. If he3 fusion is ever realized and commericalized and it is more economical than competing forms of energy there might be a "Moon Rush." It is also possible that by the second half of this century we will have solved all our energy problems, and breeder reactors might be a large part of that. Another thing we will have competition with is deuterium-tritium fusion....why go to the Moon for helium 3 if you can get yer D from seawater and yer T from the reactor lithium jacket??? And then there's all the uranium in seawater. At present, industrializing the Moon to build SPS and power relay satellites, mine helium 3 with thousands of tractors in the maria as far as the eye can see, launch materials into space to build asteroid mining ships cheaper than rocketing everything up from Earth, materials for building spaceship flleets to Mars for colonization and terraforming of Mars, and asteroid deflection systems to protect the Earth from deep impacts, as well as materials for giant space telescopes that can see and study Earth like planets orbiting distant stars, is just a dream. But it is a dream I enjoy chasing. I am an old L5 Oneillian dreamer to this very day. O'neill and his colleagues envisioned a mass driver sent up in sections by Shuttle and propelled to the Moon by H2/O2 rockets. The mass driver would shoot small multi kilogram sized packets of regolith to an L2 mass catcher then haul it over to L5 where the construction shack was. I don't agree with the artist's conception of a big sphere that opens and closes like a clam shell. I see something more like this: http://www.moonminer.com/L5-Construction-Shack.html O'Neil et al thought raw regolith should be shot into space, even though nearly half of it was oxygen, because they wanted oxygen for rocket propellant in space combined with LH2 from Earth. I tend to differ. I think we have to develop industry on the Moon and build the mass driver on the Moon. I don't think an L2 mass catcher will stay on station with so much material coming in at over 100 mph unless they use a lot of that stuff for mass driver propellant to keep the mass catcher on station. What a waste.I think it would be better to launch larger multi-ton size modules with oxygen cold gas thrusters so that the packages can retro into the mass catcher and not slam into it. Then the cold gas thrusters and regolith containers will be cannibalized at the L5 c-shack or collected and hauled back to the lunar surface. More info about lunar mass drivers: Numbers By smelting metals on the Moon we can reduce mass since regolith is 40% O2. But we may want that O2 at L5. And solar energy is 24/7 at L5 while on the Moon it is not half the time. So this is a toss up. Another thing that bothers me is that some heavy ceramic structures are going to be needed for furnaces and a little gravity would help too. Perhaps at L5 we will construct a huge rotating truss work producing say 1/10 of a gee and assemble interlocking cast basalt, fused silica or other ceramic block furnaces to smelt metals out of regolith. We will also mine for iron fines and shoot them to L5 and volatiles, so there must be a substantial amount of mining capacity on the lunar surface that is made mostly on the Moon from in situ resources. I guess we will launch various multi ton packages of metals, glass and raw regolith for its O2 content to L5, or more accurately to L2 mass catchers. As for a 10,000 man space colony, I think we have all agreed that if SPS construction is to be done it will be done mostly by robots teleoperated by Earthside personel with only a skelteon crew at L5 and at a GEO space station. It is hard to argue in favor of doing the smelting on the Moon when L5 has solar energy 24/7, but we might have a lunar globe circling power cable system in a reasonable amount of time. Burt Sharpe has talked about ( and written in his book) about starting out at Mt Malapert where you get solar energy about 89% of the time with up to six months of constant light and five sunsets per year lasting about five days each, and extending an electric cable from a solar powerplant there near the S pole that will have energy most of the time, and even building an electric RR(1) We would spiral around the Moon making shorter globe circling cable lines at the southerly latitudes and adding solar power plants along the way until we even circled the lunar equator and even the northerly latitudes. With this lunar globe circling power grid of cables, towers, inverters and transformers and solar farms we could supply energy to Moon bases 24/7 So we could do the smelting on the Moon, launch metals and finished parts like steel tubes, tension cables and I-eams etc. to L5 and there we could assemble the SPSs or relay sats (relays sats would allow transcontinental and trans-oceanic delivery of power from remote places where they are intense winds, lots of tidal power, or remote deserts where we have solar farms) . We could launch raw regolith and apply magma electrolysis to make oxygen at an L5 platform that rotated slowly to make 1/10 G I guesstimate. The oxygen could be sent down to LEO with mass drivers or ion tugs to fuel up manned rockets that have reached orbit with some extra LH2. Since 8/9s of LH2-LOX rrocket propellant is LOX, it makes a big diff. The ceramic blocks from magma electrolysis at L5 could be crushed up for mass driver reaction mass and the ferrosilicon could be treated with HF acid or fluorine gas to get vapors of SiF4 that are then decomposed with heat to get fairly pure Si that is then zone refined to ultra high purity. The iron flouride that forms would be decomposed with heat to recover F and the iron used for construction affter conversion to steel. However, HF acid and F gas are so corrosive that we may not want to deal with these chemicals at all. It might be possible to separate the ferrosilicon into impure iron and silicon by boiling them in a solar furnace in the vacuum. Iron melts and 1200-1500 C. and silicon at 1400 C. Liquids boil in the vacuum. A better way would be to take impure silicon and react it with HCl, a substance that can be handled by titanium pipes and containers, to get silane rocket fuel and SiCl4 that can be thermally decomposed to get pure silicon. See: Lunar Derived Propellant Rockets So some limited smelting of raw regolith and silicon, iron and steel would be done at L5, and lots of O2 would also result. And of course raw mare regolith can melted down for cast basalt items of all sorts at L5. There are several things Mt.Malapert has like nearby ice (therefore water, hydrogen and oxygen), solar energy most of the time, and plenty of silicon, oxygen, etc. Though this is rugged highland terrain it won't be as easy to mine for volatiles and those ubiquitous meteoric iron fines as will be it in the smooth maria, but highland regolith is rich in alumium and calcium and that's what we need for power cables that we sprial around the Moon with. We will cover the slopes of Mt.Malpert with solar panels some made on the spot. We will invert the DC output to AC then step up the voltage for long distance transmission with transformers with ferrosilicon cores obtained from magma electrolysis and aluminum windings from nearby highland regolith by some process, probably fluxed electrolysis. We will put circuit breakers in the lines. Then we will get our convoys loaded up with solar panels, coils of Al cable, FeSi cores and other electrical gizmos like big circuit breakers and capacitors to control reactance in the lines. We will also haul ceramic slab bases from magma electro to support the transformers, plenty of extra O2 in case of vehicle LSS failure, and poles made simply by casting molten regolith or magma electro ceramics into sand molds. The poles don't have to be too fancy and won't endure hi stress in low lunar G. We will string out the wires, mount the poles and work our way 90 degrees around the Moon, hopefully before sunset at Mt. Malapert. At some point, I guess 90 degrees away from Mt. Malpert's dark time, we will deploy the solar panels, transformers, etc. and build another solar powerplant. When our batteries run low, we will connect to the cable or cables we are stringing out and radio back to Mt. Malpert base to throw the breaker switch and feed us some power to recharge the convoys' batteries and fuel cells (we will need water splitting gear on one of the trucks). In this way we will spiral north and around the Moon, building solar powerplants along the way until we have electrified many choice mining locations on the Moon. We may have to branch some cables off to good locations. Transformers will need drilled passages in their cores and shielded space radiators filled with an inert gas to keep them cool. And foil sun shields. So lots of logistics and engineering details will be involved, but I think it can be done and this project might be the first huge project tackled on the Moon after substantial base infrastructure near the S pole has been built up. NASA is going to the right place in my humble opinion. Mt. Malpert is one of the richest places in the solar system with energy, ice and other substances of great usefulness. That ice, unless it is concentrations of solar wind hydrogen, we just don't know yet, might also contain CH4, NH3, etc. of cometary origin. I do not think that we should or could build a monorail concurrently with the sprialing power cables that follows the cable and takes power from it until many decades of lunar development occurs.Where would we get all the steel for tracks? There ain't so much iron near the S pole and terrain is rugged and will hamper mining for volatiles so we won't have much carbon for steel unless we rocket it up there....but then we need iron and mining for Fe-Ni fines in that rugged terrain will be hard...maybe we could get iron by magma electro for steel.... What about a conventional railway? Where will we get all the gravel for the RR track bed??? That would require major quarrying beyond the ability of the base as i envision it at this point. Then we need RR ties and there is no wood. 1000 miles = 5,280,000 feet and that means over a million RR ties made of what? Cast basalt and magma ceramics would just crack with use. Okay, we make it a monorail supported by towers and we don't need a gravel bed or ties at all but we still need a hell of a lot of steel. I say the main thing is power for Moon mining bases, so lets just launch or build on the Moon convoys of large ATV trucks for stringing out the cables, erecting the poles, constructing substations with transformers and capacitor banks, splicing off the main cables to places that are not on the spiral northward, and deploying solar panels made on the Moon. With power available 24/7 all month long the Moon becomes a more attractive place to smelt regolith for metals, ceramics, glass and oxygen than L5 and work those materials into everything from helium 3 mining tractors to solar power satellite parts that will be launched by large mass drivers to L2 then over to L5. For those who are dismayed by my bias in favor of Moon mining and smelting on the Moon instead of smelting at L5 let me say A) I forsee helium 3 mining and lots of industry on the lunar surface to build the helium 3 mining tractors and infrastructure B) Regolith does not exist in the right proportions for SPS construction. It is 40% O2 20 % Si 14% Fe 8% Ca 7% Al 6% Mg, 2% Ti and a few percent Cr, Mn, Na and trace elements. A solar power satellite will be about 50% Si and 50% Al by mass. Why not just launch the required silicon and aluminum instead of raw moondust??? We only need the 7% Al and 7% Si or 14% of the regolith's mass for SPS construction. This would reduce mass driver and mass catcher requirment by 6/7ths. And reduce work loaads at the L5 c-shack too. That's more than just significant, that's a whopper! Final Note: For long distance AC power transmission 165,000 volts and higher are used. Won't ATV trucks fry their battery packs when they recharge off the lines they string out? No. Only a few hundred kilowatts will be sent down the line for this and some small AC transformers will be hauled along to step down the voltage to a suitable level for battery recharging and electrolysis of water from fuel cells. When the system is at full power many megawatts will be sent down the lines and large transformer substations will step the voltage down to a safe and useable level at outposts and bases feeding off the main lines. Final Note 2: In anticipation of objections to the production of cast basalt power line poles and cast basalt transformer bases near Mt. Malapert where the terrain is all highland regolith and mare basalt is far, far away, I can only say I goofed. However, we can make poles and bases out of melted and sand mold cast anorthositic regolith. This will have almost the same composition as aluminosilicate glass laced with iron that makes it dark and opaque. We could also use the spinel and silicate ceramic from magma electrolysis. Better yet, use steel poles. See: Stringing Power Cables Although highland regolith is richer in Ca, and Al while maria regolith is richer in Fe and Mg, both contain alot of Si and O2 and highland regolith contains significant amounts of iron and magnesium while mare regolith contains signiciant amounts of calcium and aluminum. See: Lunar Resources Overview We can use magma electrolysis in the highlands to get ferrosilicon and ceramic. If serial electrolysis proves out we could get iron, FeSi and silicon as well as ceramic and oxygen with impurities. We could always try boiling ferrosilicon with concentrated solar energy to separate the iron and silicon. High temperatures are "easier" to deal with than extremely corrosive HF acid or F gas. So we can get iron out of highland regolith. If we can't get carbon by volatile mining in that rugged terrain we could upport some as very little carbon is needed to make large qtys. of steel. Anorthositic highland regolith is also the best stuff to roast with solar energy to drive off some SiO2 and increase CaO content to make cement mix. With ice nearby in shadowed craters and some sand or raw regolith and gravel we can make concrete near Mt. Malapert. |
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| 1) The Moon: Resources, Future Develpment and Settllement by Shrunk, Sharpe, Cooper and Thangavelu 2nd ed. Praxis: 2008 |