Geothermal energy
Geothermal energy is heat generated inside dense and rocky cosmic bodies. It can be generated by the immense pressure in the core of planets, creating nuclear processes and is constantly available with virtually no limit in time.
On Earth there are a few installations to use geothermal energy for heating and for production of electricity. On Mars there might be usable geothermal energy, as well. Yet, it is unknown how deep to drill and what's the temperature in the depth. There are signs of geothermal energy, however.
yes the wind
no the wind
