To explain the electricity system in a bit more detail:
The value represents the operating rate as a fraction (numerator / denominator).
If the numerator is 0, the operating rate is 0%.
If it’s 10/20, the operating rate is 50%.
This does not affect manual mining done by clicking.
However, it does affect automatic mining performed by machines.
That might be the reason why it sometimes feels like resources increase and sometimes they don’t.