Oh baby! Envision 400 years in the future in which there is peaceful co-existence on Earth between humans and sentient mechanical life forms.
Earthers – humans and machines originating from Earth -- have solved the time/distance dilemma for in-system space travel and are on the prowl to inhabit one of two moons: Enceladus of Saturn and Jupiter’s Europa.
Instead of using head distance to power several hydroelectric projects on the surface of Enceladus, project owners decide to harness hydropower at mapped geyser locations. On Europa, the first-ever off world tidal energy system will harness energy from the moon’s vast sub-surface liquid oceans.
Many astrobiologists regard the 310-mile-wide Enceladus and the much larger Jupiter moon Europa as the solar system's best bets to host life beyond Earth.
Since 2005, scientists have mapped more than 100 geysers on Enceladus that regularly spew ice crystals miles into space from its surface. Using material harvested from nearby asteroids, project owners could develop robust runners for turbines to use in a system akin to a run-of-river project on Earth.
Of course all of this would happen because the Federated Earther Responsibility Commission (FERC) has deemed Earther nuclear power too hazardous for use on uninhabited planets. FERC thinks one can never take any environment for granted.
On Europa, sentient machines could emplace tidal energy farms to first use as a sustainable power source to recharge their own systems and then build upon initial emplacements to sustain human life.
Far-fetched? Perhaps. This scenario is “far off” if viewed in terms of your lifespan, but it is certainly not complete science fiction from a hardware standpoint.
Could hydropower – power derived from water – albeit in this case ice and sub-surface tidal energy be a gateway to off-planet habitation? Ask me in 400 years.