What are the optimal setups for planetary interaction?
Solution 1:
After some research, turns out that a really good way to manage power grid is to stretch the whole colony into a big line.
This way you save power grid necessary to put extractors close to hot spots, with the addition that you have a lot more room to move extractor heads (since the extractor itself is near the hotspot).
I'll accept this answer in few days if nobody else answers.
Source:https://www.reddit.com/r/Eve/comments/5v6v8i/simple_p2_pi_setup_help/