[ExI] Power satellites microwave power transmission

[Keith Henson]

On Thu, May 26, 2011 at 12:32 AM, The Avantguardian
<avantguardian2020 at yahoo.com> wrote:

snip

> Hey Keith. I am sure you are aware that I am proponent of SBSP but one thing
> that troubles me is that I have yet to see a good plan to get rid of the waste
> heat generated by gigawatt power generation in the vacuum of space. Do you have
> any suggestions on how to cool an SPS so that the resistance of the power
> conduits does not choke off the power supply? Anybody?

For large radiators, the dominant mass is the heat transfer fluid.
Back in the late 70s Eric Drexler came up with an idea for a pseudo
fluid of dust and gas where the heat capacity of a gas was increased
to that of air or more while reducing the pressure to near zero.  The
original articles are linked here:
http://www.nss.org/settlement/L5news/L5news1979.htm, see July and
August issues.

More recently I worked out the best temperature for a carnot cycle
engine.  Assuming the per kW mass of light concentrators and radiators
is about the same, the ideal temperature came in around 100 C with a
fairly broad optimum.

Taking these together, space radiators using dust and low pressure gas
in rubberized fabric like an air mattress can dump about 1/4 kW per
side per square meter.

Half a GW takes a square km of radiator.

Any solid can be ground up and used for radiator pseudo fluid.  Lunar
regolith run through a small vibratory ball mill would work just fine.

Keith

> Stuart LaForge
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