and we don't use sterling engines from whatever fuel source is what? if it is dependable enough to be in space where there is no mechanic then is sounds reliable enough for my backyard front-yard porch...

can apply to Manned Space IE ISS or Lunar base??

Sounds like a really good idea. (Kind of thinking somewhat out of the box.) Now you'll probably have some environmentalist raising a stink about "Nukes in Space".

Pretty amazing how it's able to dump waste heat space into near vacuum. I wonder how the thing is going to look like for a 1-kilo watt power generator

@hogi90 For earth based engines there are more effective and efficient options. Mainly Stirling engines end up being lower power and torque for there size.
@Stephen Earth orbit and the moon are inside Mars orbit so Solar is a much better option. Also for manned operations the power budget would be much higher and need a larger more complex reactor. As an example the ISS solar arrays generate 84,000 Watts while the RTG on the Mars science Lab only generates 125 Watts.

@hogi90 @Douglas Also, we do use Stirling engines for some things. Here's a common use, for example:
http://solar.calfinder.com/blog/products/stirling-engine-addresses-large-scale-solar-power-concerns/
Wikipedia has a decent overview of some advantages and disadvantages of Stirling engines versus internal combustion engines:
http://en.wikipedia.org/wiki/Stirling_engine#Analysis

I'd wonder if neutrino fired hydrogen peroxide would function similarly in deep space as it does miles underground.

Sound cool. Forget about space, I want one at home. But dont heat pipes require gravity to function?

Ok never mind my comment about gravity. The wikipedia tells me one can make a heat pipe with capillary force in place of gravity. So clever.

The Feynman's lectures on physics level question is - In a capillary heat pump what energy source moves the lquid from cold side bacl to hot side?