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Missile Defense

Technology has always found its greatest consumer in a nation's war and defense efforts. Since the last attempts at a "Star Wars" defense system, has technology changed considerably enough to make the latest Missile Defense initiatives more successful? Can such an application of science be successful? Is a militarized space inevitable, necessary or impossible?

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rshow55 - 12:37pm Jun 30, 2003 EST (# 12763 of 12764)
Can we do a better job of finding truth? YES. Click "rshow55" for some things Lchic and I have done and worked for on this thread.

It seems to me that if we're to adress our energy problems with a solar approach - it makes sense to look hard at putting the collectors on equatorial oceans. That is where the sunlight is, where the calm conditions are - and where the area is.

gisterme: 2136-7 http://forums.nytimes.com/webin/WebX?8@13.gubGb3E5lTT.1257058@.f28e622/2652 includes great questions about the equatorial solar energy proposal I've made. I've reordered some of his points, and give some short responses to some of them here. I'll deal with the rest of them within the next few hours.

gisterme: "How would you transport energy back from your 460 km square floating solar array to someplace it would be useful? Did you say "as hydrogen"? "

For a lot of reasons, I'm thinking of many solar arrays of perhaps 1 km/10 km - rather than one big one. Yes, I'm thinking of hydrogen. I'm thinking of transportation of the hydrogen by sea - supply of the hydrogen at the collectors (at a "shadow price" of perhaps 10$/barrel equivalent of energy) is one problem. The transportation (at a "shadow price" of 5-10$/barrel equivalent of energy) is another problem. Both problems have to be solved in economic terms. The stakes are high enough to justify careful, extensive design studies on the problems involved - studies with many iterations on the important issues - so that near-optimal solutions can be identified and worked out.

gisterme: "Would electricty produced by the array be used to to operate a giant electolysis plant or plants, also floating with the array to separate the hydrogen from water?"

Yes, electrolysis. Supposing 1km/10 km collector size and 20% efficiency, each collector would generate 2 gigawatts of power at noon. For reasons of conduction distance, and the economies of mass production, - and I think it would make sense to have the electolysis done in something like 100 floating electrolysis units of 20 megawatts each - each operating at high pressure - with hydrogen collected from the electrolysis units on a routine (perhaps daily) basis.

gisterme: "How would you desalinate the seawater as would be necessary prior to that process?"

You're right that the water used in the electrolysis units would have to be well distilled - because impurity buildup on the electrodes would be intolerable. I think that can be done at a cost of the order of pennies/barrel energy equivalent produced, but I'm aware that current costs would be much higher. Two years ago I said this: "Seawater distillation could be achieved at an energy cost not much more than twice the thermodynamic limit cost. I believe that cost per liter might be 1/10 to 1/50th the cost today. Scaling to serve cities and countries would be feasible." http://talk.guardian.co.uk/WebX?14@@.ee7a163/295 - I still think that's true, but I haven't filed a patent on it (though I did a patent search on the idea, years ago.) Perhaps I'm wrong - but the ideas involved are simple and can be checked. I'd be willing to present the idea, given a few days notice - to engineers at the University of Wisconsin, WARF, or anywhere else convenient to the government or other interested parties, if it could be done on a confidential basis.

gisterme: "What would be the end-to-end efficiency of that desalinazation/hydorgen production process? Is the massive energy required to do those process steps taken into account in your calculation of array size. . . . ? "

I'm assuming that the energy cost of distillation and electrolysis are small - hydrogen-oxygen fuel cells of 98+% energy conversion efficiency are possible - and energy conversion efficiency of electrolysis units over 95% should be possible in high volume production.

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