my estimates were 2 zips but i ve been reading and some people are yielding 1.5 zips try off one plant and if that is true then we are looking at 4.5 zips
If your lights are incandescent then you wont get much but if you had compact floros or cfls than expect higher yeilds. Again pictures are more helpful, because yeild is strain dependent as also the growing enviro...
CFL's are only good for vegging in my opinion, for flowering you want atleast some kind of hps. Three cfl's for three plants is really bad.. Either get a shit load of em and cover your plants with them or get an HPS.
Good luck