So tidal power plants are a thing. They harvest the energy from water moving around. That energy comes from somewhere, specifically the moon, right? So does harvesting tidal power (very very very) slowly degrade the moon's orbit? Does liquid's existence on earth deteriorate the orbit to begin with? I mean, perpetual energy is not a thing, right, so the system has to deteriorate somehow... How does a tidal energy system deteriorate? How long would that take?