I don't know if this came up but here is my suggestion:
It concerns renewable generators. Is it possible to add fault mechanism to those generators. Similarly as bees die of randomly in forestry.
Once the generator is broken, it could be repaired with appropriate tools. (Solar panel with soldering iron, wind and water mill with hammer and wrench)
Mean period of breaking in minecraft days can be set in options. It sould be based on time the generator has been operating, not just on time passed.