I would develop perpetual energy chambers. It's a simple concept really. Zombies apparently defy the laws of thermodynamics in that they are able to move about unceasingly with no means of metabolizing food into energy. "But Wallydraigle, zombies eat brains and stuff!" That's true, but this is apparently not necessary for zombie survival. In all my years of watching horror movies I've never seen a zombie starve to death because he can't get any brains. This is in part due to the ready availability of 18-29 year old brains, and partly due to the fact that zombies are already dead, and cannot die. They don't have a heartbeat, so no circulation either. Any brains they do eat just end up sitting in their rotten stomachs until they are pushed through their fetid bowels by the eating of subsequent brains. Do zombies poo? I don't know. Maybe if they eat too many brains they just pop like a seagull that eats Alka-Seltzer. That would suck, but if you're already dead I guess it wouldn't matter anyway. Zombies eat brains because they like to. That's just what they do. It's their only joy in existence. If zombies didn't run around eating brains all night then they would just be pointless and no one would make movies about them anyway.
So onto the perpetual energy chambers. Apparently all that is needed is to round up a bunch of zombies, throw them into a sealed chamber from which they cannot escape, with a really big treadmill as a floor. Place brains at the far end of the chamber, and the zombies run (shuffle? shamble? they "move" in some manner) forever towards the brains, which they can never ever get to, and so they continue to chase them for all time, all the while producing electricity from the generators attached to the giant treadmills. If you want to get fany you can use some of the electricity generated by the zombies to produce a "hologram" of the brains so you don't have to continue to add real brains as they rot away.
Maintenance on such a system would be a bitch. If one ever broke down it would probably be better to abandon it and start over in another site with fresh zombies.
That's what I would do.