[ExI] 10 mega construction projects that could save the environment and the economy

[Keith Henson]

On Sun, Dec 4, 2011 at 5:00 AM,  Anders Sandberg <anders at aleph.se> wrote:

> Keith Henson wrote:
>> Lunar ring is a variation on space based solar power, usually based in
>> GEO.  I see it as a factor of ten more expensive per kW, but have
>> never actually done the numbers and have never seen anywhere where
>> they have been done.
>>
> Think they are in Criswell's original paper. In this paper
> "Lunar Solar Power System: Industrial Research, Development, and
> Demonstration"
> http://www.agci.org/dB/PDFs/03S2_DCriswell_LSP.pdf
> he estimates it as 1.4, 0.2 and 0.06 dollar per kWe depending on expansion.

There are several problems with this paper, including the sparse array
curse, and the need for a lot of reflectors (or high loss
rectennas/transmitters in space so the power comes down in the places
where it is needed.

Then there are the complications of making very large amounts of
materials on the lunar surface, particularly aluminum power conductors
to get the power around from the far side during new moons.

But the killer is their cost (in dollars per kWh), which I suspect is
way too low, but accepting their numbers, 6 cents is just not low
enough to displace fossil fuels.  To do that takes 2 cents per kWh or
less.

That said, I can see where such a proposal would work, in a world of
nanotech.  But if we have nanotech, it's not obvious to me that we
need much energy at all.

Keith

> Found some related stuff:
> http://www.aip.org/tip/INPHFA/vol-8/iss-5/p28.pdf
> http://www.aip.org/tip/INPHFA/vol-8/iss-2/p12.pdf
>
> --
> Anders Sandberg,