From: utzoo!decvax!cca!Ciccarelli@PARC-MAXC@sri-unix Newsgroups: net.space Title: Re: Reactors on the Moon Article-I.D.: sri-unix.3304 Posted: Thu Sep 16 09:53:09 1982 Received: Fri Sep 17 03:19:54 1982 On Earth, nuclear reactors are (by some arguments) a cost-effective power source compared to alternatives. On the Moon, *no* such advantage exists when compared to the obvious competitor: sunlight. Consider the following criteria: [Generator site] Nuclear: If you build it "dirty" and unshielded (as suggested), its users must be some distance away, at least outside the crater. Solar: No site restrictions. Power is generated where needed, without long transmission lines. Move the power station when you need to; it's not "hot", large, or heavy (especially with photovoltaics). [Fuel] Nuclear: (a) Launch it from earth, *if* your citizens and the rest of the world don't object to the possibility of an unexpected "hot" shower if the launch vehicle fails, or (b) Find it (if it exists), mine it, and set up and power a separation plant on the moon (not worth considering). By the way there's the nasty detail of reprocessing breeder output. Presumably this involves robots or highly-paid humans, not to mention a plutonium remanufacture facility. Sounds complex... Solar: Spread a thin reflective sheet, or set up your photovoltaics! No hot waste to reprocess, either. [Electrical generator] Nuclear: (and Solar) could run a turbine (such a solar turbine has been proposed for an orbiting solar power satellite), but turbogenerators have to be shipped from Earth until you can make them "up there", and they have certain economies of scale (lower efficiency when made smaller). Solar: Photovoltaics would be much easier (than turbines) to make "locally", since no iron is involved and silicon is plentiful. They are usable in ANY size; just connect enough cells in series and/or parallel to provide the desired voltage and current. They have NO moving parts, aren't "hot", and are easily relocated. There's no downtime or power reduction during repairs since you can replace modules without shutting down others in the array. [Industrial process heat, i.e. for smelting and reduction of rocks] Nuclear: Heat can't be used directly without shielding (if you expect to have humans anywhere nearby...). This means electrical conversion (lossy) and reconversion to heat or RF. Why bother...? Solar: Easier than power generation; just aim mirrors at whatever needs the heat. Turns on and off instantly; not true for a reactor. ...Lastly, I abhor the "run it till it melts down, then bury it" school of engineering. The same goes for the "launch the wastes into the sun" suggestions. Why *create* these problems in the first place, when obviously better paths exist? I'll be damned if I'd like to be the 22nd-century lunar homesteader who happens to encounter your (oops, mistakenly unmarked) plutonium waste dump. /John