A recent answer suggested using "methane and other hydrocarbons" for geothermal energy recovery on the Moon.
You would not need to use water [on the moon]! You could use the methane and other hydrocarbons that could be used.
As organic compounds I have difficulty imagining their presence on Earth's Moon. I know they are plentiful on both Earth & Titan, but not sure about our Moon.
Are there hydrocarbons on the Moon?
If so how did they get there?
I think the poster was mistaken about hydrocarbons being on The Moon. We know some planets (like Mars) and moons (like Titan) have them, but not Earth's. The Moon does have water, however. What probably threw him is how we know it has water
Water (H2O), and the chemically related hydroxyl group (-OH), can also exist in forms chemically bound as hydrates and hydroxides to lunar minerals (rather than free water), and evidence strongly suggests that this is indeed the case in low concentrations over much of the Moon's surface.
Hydroxyls exist wherever water does, given that they are made up of only oxygen and hydrogen. Hydrocarbons also need carbon, which no report I can find indicates is on the moon (at least in that form). That having been said, it is entirely possible to use hydrolysis on water (and possibly hydroxyls) to make hydrogen fuel. I think that's what they were driving at.