Nuke vs. SPS ( Population reduction isn't necessary for wilderness)

--- In spacesettlers@yahoogroups.com, "hitssquad" wrote:
>
> --- In spacesettlers@yahoogroups.com, "sailor.barsoom" wrote:
> > --- In spacesettlers, "hitssquad" wrote:
> > > Energy from space (to Earth) isn't realistic, given the presence of cheaper alternatives.
> > a) it's so expensive to launch anything into space,
>
> A dirty secret of SPS is that its cost varies minimally with launch cost. Assume launch cost is $100/kg, and show us on paper a plan for building SPS in GEO at an overnight cost of less than a quadrillion dollars per gigawatt.

Where are you getting your numbers from?

> > c) the alternatives are are not priced according to their full cost
>
> Is that falsifiable, and do you have a plan for changing that even if it were true?

Pollution has a cost, that cost is not paid for by the polluter. Add a tax to pollution that address that cost. A carbon tax, which is used by almost 2 dozen countries and within 3 US states, is a plan.

> > > Also realistic would be 100 trillion on Earth, and another 100 trillion on Venus.
> > calling this "realistic" while saying that power from space solar is not, is pretty silly.
>
> It doesn't suffer from the tidal-force problem, while Earth-orbit-SPS does. Also, all of the technologies needed for the former already exist. No one knows how many-kilometers-wide structures in GEO would deal with the tidal forces, because, so far, no one has bothered investigating it even via mere computer simulations. Another dirty secret of SPS is that it isn't subject to economies of scale. A principal reason for that is the tidal-force problem (a problem not encountered at my suggested SPS locations of Sun-Earth L1 and Sun-Venus L1, by the way).

Only if the structure is one solid piece, if it is in sections that can move away from each other and then closer during rotation than tidal forces shouldn't be an issue.
Brooks