Overclocking power generators is a misunderstood concept, however if you're keen to go out and get slugs for the power shards then you can reduce the amount of generators required by 50% for the same amount of power output.
A discussion about how the Mk. 4 Conveyor Belts and how the miner and node type play an important part in utilising them.
Overclocking is how you can increase the production rates of the machines in game. Underclocking allows you to reduce the power consumption of machines, but at a reduced output rate.