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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 - 05:00pm Jun 30, 2003 EST (# 12770 of 12775)
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.

Gisterme makes a very good point about alternative siting for solar collectors:

" I think the better place for the array would be in a large desert like in northwest Africa, the Austrailian outback or the southwestern US. You could lose an array that size in the western desert of the US and still be close enough to consumers to feed the electricty almost directly into the existing power distribution grid without all the weather dynamics, corrosion, conversion and transportation problems posed by a seaborne array."

Solar arrays on land would have different problems from the problems a seaborne array would have - and these problems would correspond to different engineering and running costs, including opportunity costs.

When I looked at solar intensity, availability of area, and structural and cleaning issues of arrays on land versus arrays on equatorial oceans - the oceanic approach looked more feasible to me - enough more attractive to justify likely transportation costs.

Gisterme is right that the idea of distributing energy on land as electricity, instead of hydrogen, is very attractive. Fuel cells are extremely efficient thermally - and with hydrogen available - potentially very cheap per gigawatt. If hydrogen was delivered from the sea - it might still make sense - at first and maybe indefinitely - to convert it to electricity and use it as a petrochemical feedstock to upgrade carbon rich fuels - with little change in fuels from a consumer's point of view. Although the efficiency of fuel cells, with hydrogen available, makes it an efficient transportation fuel - something the large auto manufacturers are clear about. The "massive new energy distribution infrastructure that conversion to a liquid hydrogen energy economy would require" might not be needed - because conversion to a totally hydrogen economy wouldn't be needed. It seems to me that hydrogen would interface well with existing energy sources and capital installations, from early prototype stage to the largest possible scale.

Is ocean based solar power a unique alternative?

No.

But it is an alternative - one that offers engineering challenges - but no difficult scientific challenges at all. I believe that I've provided some background to the question If you wanted to permanently solve the world's energy supply problem using a solar energy - hydrogen approach - what would it take? 12737 http://forums.nytimes.com/webin/WebX?8@13.9HOhb6fslYt.1393521@.f28e622/14405 . It would take a lot of area. It would take a lot of money.

There are always different ways to do things. Each may be optimized in terms of specific assumptions - and with work - both the assumptions and the optimization can be very good. Then you pick the best alternatives - or try to.

I think that the equatorial proposal would work - and my guess is that it is likely to be the best alternative, considering everything. But the cost of simulation is now much, much lower than it has been - and it should make sense to evaluate a lot of basic approaches.

Optimization is "doing the best you can." It takes some work to find out what "the best you can" is. 12759 http://forums.nytimes.com/webin/WebX?8@13.9HOhb6fslYt.1393521@.f28e622/14430

But our nation and our world are not without alternatives to petroleum. Good alternatives. I think we should pursue them - and I'm working to move that along.

jorian319 - 05:13pm Jun 30, 2003 EST (# 12771 of 12775)

Hydrogen's lighter-than-air characteristic makes for a surprising "explosion" profile. In open air, it seeks to rapidly disperse upward and outward, and a goodly fireball can result. But since it is already rising, damage on the ground beneath it is minimal. This is unlike propane or other gasses that can "pool".

lchic - 10:29pm Jun 30, 2003 EST (# 12772 of 12775)
~~~~ It got understood and exposed ~~~~

"" Investigations in both the US and Germany found that the explosion was caused by a build up of electrostatic charge which ignited the hydrogen inside the airship. Next week, however, two American researchers will present evidence at a symposium in Turkey that the material used to coat the skin of the airship caused the explosion. They also believe that the makers of the airship, the Zeppelin company, knew the real reason for the crash, but blamed hydrogen for 'political' reasons. http://physicsweb.org/article/news/2/6/1

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