Vacuum pyrolysis of lunar oxygen

[A_M_Swallow]

Max energy produced received is 1.366 * 2 * 2 * 0.9 = 4.9176 kW (or 4917 W)

Unless I misread your comment, you haven't yet produced electricity; you've received the Sun's rays.  Just sayin'.

The question was about the mirrors.

A solar furnace does not need to convert to electricity since it can use the heat directly.

[Bill White]

Max energy produced received is 1.366 * 2 * 2 * 0.9 = 4.9176 kW (or 4917 W)

Unless I misread your comment, you haven't yet produced electricity; you've received the Sun's rays.  Just sayin'.

Electricity? Vacuum pyrolysis don't need no stinking electricity!

= = =

That said, capturing, distilling and liquifying gaseous oxygen will need electricity -- just a lot less electricity than by doing the electrolysis route.

Therefore figuring out how to extract electricity as a by-product of vacuum pyrolysis remains a worthwhile objective.

[A_M_Swallow]

Okay, the (.007 * 2 * 2) is 4 square meters of mylar (the aluminum coating doesn't add mass to the mylar?)
{snip}

That "mylar" is solar sail material so the mass of the aluminium layer is already included.
http://en.wikipedia.org/wiki/Solar_sail#Sail_materials

The Earth based systems included motors to track the sun.

[Bill White]

What about mounting reflective Mylar on aerogel?

Fabricate parabolic troughs from aerogel and line with Mylar? Those won't have very much mass. Attach the troughs to an aluminum rod and rotate (rotisserie style) to track the sun.

I wonder of the fiber optic application described in the following paper could be modified to work with parabolic trough collectors:

http://www.psicorp.com/pdf/library/SR-1395.pdf

The absence of atmosphere and 5/6ths less gravity would seem to suggest that lunar solar collectors could be considerably less massive than terrestrial versions.

[Hop_David]

Okay, the (.007 * 2 * 2) is 4 square meters of mylar (the aluminum coating doesn't add mass to the mylar?)
{snip}

That "mylar" is solar sail material so the mass of the aluminium layer is already included.
http://en.wikipedia.org/wiki/Solar_sail#Sail_materials

The Earth based systems included motors to track the sun.

But no such motor was mentioned in your 2.028 mass. You still haven't provided a credible Watts thermal/kilogram figure.

[Hop_David]

What about mounting reflective Mylar on aerogel?

Fabricate parabolic troughs from aerogel and line with Mylar? Those won't have very much mass.

Nice observation!

It may seem like I'm an S.O.B. hellbent on tearing down this notion. That's not the case. It's my belief that an aggressive devil's advocate can do more to validate a worthy notion than an enthusiastic cheerleader. Your aerogel supports is just the type of response I was hoping for.

If you can find mass of rotisserie, mass of aerogel needed to provide support, plus mylar, I believe we could get a credible watts thermal to kilogram figure.

[A_M_Swallow]

This Stirling convertor aims to have a specific mass of 6 kg/kWe and an overall efficiency of 25%.
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080012733_2008011106.pdf

"The SCA is designed to operate at a hot end temperature of 830 K, a cold end temperature of 415 K, with a nominal power output of 5 kWe, a peak power output of 6 kWe with overstroke, and a design life of 5 years (44,000 hr) of continuous operation at 100% power level."

The Heat in is 24863 W to produce Electric out of 5084 W.

[A_M_Swallow]

{snip}
That said, capturing, distilling and liquifying gaseous oxygen will need electricity -- just a lot less electricity than by doing the electrolysis route.

Therefore figuring out how to extract electricity as a by-product of vacuum pyrolysis remains a worthwhile objective.

If liquid metals are being produced they will need cooling after they have been cast.  There are techniques to convert waste energy into electricity or to pre-heat the raw materials.
http://en.wikipedia.org/wiki/Waste_heat_recovery_unit