I'm not certain what you have in mind by "an energizer made specially for chickens"... there really isn't any such thing. Your choices for energizer type are basically either: constant-current (i.e. not pulsed -- this is unnecessarily dangerous to people and animals and I don't recommend it), weedburner type pulsed-current units, and modern 'normal' low-impedence units. (YOu can argue about details, as far as wehther there are some things ont he market that don't quite fit the latter category exactly, but for our purposes here the difference doesn't matter)
I would strongly recommend a normal low-impedence pulsed unit, which is most of what's on the market anyhow. (Weed-burner sounds nice in theory but in many climates is a significant fire risk for part of the year.) Can be plug-in or battery operated, whichever you prefer.
A foot between wires is kind of iffy IMO -- chickens will for sure pop through it sometimes, and some predators may too. (Remember that electric fencing for chickens is much more to keep predators OUT than to keep chickens, who can fly over the fence anytime they choose unless they are CornishX broilers, in). Also, unless you have very stoutly set corner posts and fairly closely spaced line posts, you may have trouble keeping the wires that exactly straight. Putting a spring or other tensioning device in line with each of the wires will help, but only if your corner posts are good, which in most soils will mean well-set wood rather than t-posts.
Honestly, there are probably better ways of accomplishing the same thing (like woven wire fencing with a couple lines of electric offset on the outside to discourage predators). If the area is too large to be able to afford that much woven wire fencing, it is probably also too large to be able to maintain your many-parallel-close-spaced-wires fence with adequate tension and precision to keep things from popping through it and eating the chickens.
JMHO, good luck, have fun,
Pat
