Lunar(geo)thermal energy is not generally much, but there may be a
very few locations where there is something. For example, in the Aristarchus
Crater region there are persistent reports of "glowing clouds" and
photographic evidence of recent small-scale volcanic activity (B. Ray Hawke
and Cassandra Coombs are a couple of researchers who come to mind
immediately). Anomolous warm magma may be near the surface there.
Lava tube caves being underground share in the
relatively constant lunar underground temperature of -20 C. Not sure if we
can use this. Caves we work in might have an overheating problem due to the
poor thermal conductivity of the surrounding material.
Actually the temperature difference
between the outside and the lunar
interior is only middling as working thermal gradients go. Still, using the
right working fluids we might be able to make this temperature difference
work for us (one way during dayspan, the opposite direction during
nightspan). Let's look for appropriate working fluids/gasses.
The figures given earlier for change in heat over time appear to make
an assumption that the heat increases or decreases for the whole dayspan or
nightspan. I believe most of the temperature change takes place in a few
hours, perhaps as long as two or three (24-hour) days, then stabilizes at the
quoted day or night temperature for the rest of the fortnightly span.
Content by Bryce Waldin