powerMon.lua

--getEnergy()
--getMaxEnergy()

batSide = "left"
genSide = "back"
setLevel = 0      --what % energy to turn genny on.
resetLevel = 95   --what % energy to turn genny off.

running = false
mon = peripheral.wrap("monitor_0")
bat = peripheral.wrap("batSide")
maxEnergy = bat.getMaxEnergy()
rs.setOutput(genSide, running)

while true do
  energy = bat.getEnergy()
  level = (energy / maxEnergy) * 100
  if running then
    if level >= resetLevel then
      running = false
      rs.setOutput(genSide, running)
    end
  else
    if level <= setLevel then
      running = true
      rs.setOutput(genSide, running)
    end
  end
  print("Energy: "..energy.. "/"..maxEnergy.."     Level: "..level.."  Running: "..tostring(running))
  sleep(1)
end