When we lived in NC we were gone for months at a time too. We turned off the water but left the power on with lamps on timers. Our neighbors parked their cars in our driveway and we had someone come mow so the place looked lived in. It worked so well while we were gone a new neighbor moved in across the cul-de-sac from us and didn't know someone wasn't living there.
If you feel insecure I'd get a security system therefore leave your power on. I'd also have someone come check on the house often, keep the yard and sidewalk cleared off, etc. The absolute best thing is find someone to actually live at your house to keep it more secure.