I personally use HV solar arrays from the Compact Solars mod. I've built an almost completely automated production line (using BC 2.x, Redpower and IC2) that takes UU matter from my mass fabber and turns it into solar arrays. It's not fully automated, since I still need to pop in ever so often and run the cobblegen to create glass and cobble (glass is automatically made) and I need to manually supply the transformers, but I've essentially got hands-off exponential growth now.
I made a factory which produced everything from UUM without needing any input from outside. It even extracted all left-over materials (rubber, wires etc). And best of all, it was lag-free.
Only downside is that the uum->iron recipe was blocked by the server admin soon after the completion of the factory.
(History repeating itself, eh SpwnX?)