I think it's possible to combine both the energy grid and psi as ways to control territory. IIRC the reason why it was suggested to use the energy grid as concept for culture is because you need the energy grid connected everywhere to power up all the various terrain improvements etc outside your base. But of course, being able to supply energy somewhere is pointless if it's too dangerous for your colonists to move far away from the base without being whacked by mind worms. So from that point it makes sense that Planet-unfriendly factions will have a harder time controlling the area far away from their base (see the proposed Planet value on base level). If you are strong in the Psi force however, you can either use these powers to befriend the mind worms, making it easier to control the surrounding area, or create a psi field around your base repelling the mind worms.
A common explanation of what psi really is, was to consider psi the fifth fundamental force in the universe, besides gravity, electromagnetism, weak and strong interaction. So basically psi would then also be just another form of energy, and using Progenitor technology, you could create machinery which emits a psi field, forming a resonance grid, whatever you want you call it, which transforms energy into psi and also repels native life. (In game terms: the turn commerce into culture process)
So basically I think energy grid and psi control can be perfectly combined.