I lived entirely off the grid when I first moved to my current home for 7 years (been here now 12 years). It's not necessarily as fun as it sounds nor romantic. It's actually a bunch of work and requires almost daily attention. That being said I needed an instant, inexpensive way to fence my property without grid power. Hot wire fit the bill. I originally built my own fence chargers using an electronic bistable multivibrator of my own design that let me change the pulse and rest time of the pulsing fence charger. It also used a standard automotive coil that can be found in any junk yard and tested with a standard ohmmeter. I added to these a 100 amp hour battery, 10 or 20 watt solar panel I scrounged from the dumpster at a previous employer and an ASC brand 8 amp solar charge controller. These worked fine but I needed several of them and the homebuilt controller took much time to build and test. I opted for the store bought 12 volt versions that cost me anywhere from $60 to $90, depending on the mile rating (the higher the mile rating, the hotter the shock). I've also tried some of the integrated models that you can buy at feed, farm supply and even big box home improvement stores. In a word they stink. None of the models I tried lasted. Like bee-nuts I think that the fence charging system with discreet panel, battery, fence charger and solar charge controller are the best solution. When one part of them fails you can troubleshoot and replace just the broken part. By over-engineering you can build a fence system that will outlast the longest string of cloudy days and keep your fence hot overnight. From my experience it's definitely the way to go.
I know of a few folks that bait their fence with bacon for a range of critters, including bear. Hot wire is a psychological barrier. The targeted animal must be trained to avoid the hot wire. Baiting accomplishes this. There are several other things you can do to make sure you deliver the hottest charge possible to the bear. The first thing is use more than one ground rod. The most common shortcoming of electric fence systems is the poor grounding system. It's like the antenna that sends the charge through the ground to the animal that you intend to shock. You can also alternate hot and ground wires so that when the animal gets their nose between the two wires they feel the full force of your fence charger. Another thing I've seen people do on small yards like an apiary is run chicken wire on the ground around the yard, hold it down with tent stakes and tie it to the ground side of the fence charger. This way the targeted animal stands on the chicken wire, touches the hot wire and feels the full force of the fence charger(a great way to overcome dry soil during a drought). Suffice it to say I've done a little research on the topic and made just about every mistake possible.