Earth's core's heat is renewable, but only in geological timescales. Not in the next 1000 years. Same as oil. That's why we don't count it as renewable: It's not renewable on a human timescale.
AFAIK geothermal is not renewable, in other words, all of the underground heat is just stored there from the formation of earth, but once consumed, it doesn't regenerate.
Probably, the only real intensive labour times were sowing and harvest. Apart from that, I can't fathom what would possibly justify 40 hrs/week work times the rest of the year.
solar panels will do a lot to reduce the problem of climate change significantly.
I'm saying this because I see a lot of young people having depression due to climate doomerism, and realizing there's an effective strategy that can be physically implemented helps a lot.
Earth's core's heat is renewable, but only in geological timescales. Not in the next 1000 years. Same as oil. That's why we don't count it as renewable: It's not renewable on a human timescale.