Electric fencing is a highly effective tool for keeping bears out - but it has to be done right!  
We recommend that you start by learning more about it from the following Youtube video by Gillian Sanders of Grizzly Bear Coexistence Solutions.  Gillian has worked with many farmers and ranchers in British Columbia to set up electric fence systems to successfully protect beehives, livestock, fruit trees, and other highly desirable bear attractants.

How to Install Electric Fencing for Bears

Gillian has also allowed us to share the following PDF document in which she has detailed the important considerations and instructions to follow when installing "electric fencing for bears".