[ExI] Space Based Solar Power vs. Nuclear Fission

[hkhenson]

At 03:50 PM 5/18/2008, Kevin wrote:

>On 5/18/08, hkhenson <<mailto:hkhenson at rogers.com>hkhenson at rogers.com> wrote:
>It isn't *a* power station, it's a new 5 GW one every 5 days for the
>next 50 years.  And that's just to replace fossil fuels and a little
>growth the bring China and India up.
>
>I don't quite understand how that works.  Are you saying that 
>somehow these power satellites bring in an exponential amount of 
>power with respect to time?

Linear.  I am taking the wedge of 13,000 GW at the peak (about now) 
that we lose as fossil fuels give out and replacing it plus some over 
the next 50 years.  In rough terms that's 20,000 GW over the next 50 
years or 400 GW a year.  Roughly a GW/day needs to be added, most of 
that to replace failing oil.

>Or are you just talking about adding additional units?
>
>But that brings up another question: is there really any limit to 
>the number of SPS's we can stick up there?

Sure, eventually they start shading each other.  Space 250 miles 
apart there is room for 3000 of them around GEO.  At 10 GW each, 
that's 30,000 GW.  So you do run out of space at GEO.

>Once we have enough to meet our current needs, why stop there?  We 
>could be swimming in energy, enough to make $1/gal for gas sound 
>expensive, and we could pretty much do anything we want.  A lot of 
>the projects that now seem to expensive and infeasable would 
>suddenly seem--easy.  And the bottleneck would again be human ingenuity.

That's usually the case.

>Not to mention that such a project would put both government and 
>commercial interests into space in a big way, making space 
>colonialism practical: afterall, *someone* has to maintain those 
>satellites, and it would be somewhat cheaper to have workers living up there.

Of course.

>But I doubt things will develop that far before the singularity.
>
>Why not?

Not enough time.

>And a singularity isn't really on my radar right now; and if not 
>enough is done and the world does go into an energy crash and we 
>return to subsistance living, I'm pretty sure that destroys any 
>chances of a singularity happening.

It depends largely on how much continuing support science gets and 
what areas are worst affected.  There are places in the world where 
the entire population could die without having much effect on the 
timing of the singularity.

>It depends on what they are making.  Besides being burned to make
>electricity, coal (and oil) are feed stocks to make all sorts of
>things like plastics.
>
>That's the thing, fossil oil is going to become scarce no matter 
>what, and I wonder if we're talking about the end of plastics.

No.  You can make plastics out of anything with carbon.

>Besides, what are those photoelectric cells made of? are they oil products?

No.  Silicon, next element over.  It's obvious you have not had 
chemistry yet, take it next year.  Or read a textbook.  Or both.

>We'll basically have to find an alternative method for making 
>plastic, or an alternative to plastic.
>
>Transitioning from oil products to electricity as our primary source 
>of energy is going to mean a great deal of transitioning in our 
>economies and national infrastructures.

Yes and no.  It's easy to substitute electricity for process heat.

Electricity is the best energy source for a lot of uses.

Keith