This spring I will be doing a lot of work on my detached garage. One of the problems I want to take care of is the electric water heater. It is nearing the end of it's useful life and it's in the detached, uninsulated garage. The winters here in South Eastern Virginia aren't very severe and I do have an insulating blanket on the water heater and foam insulation on all of the pipes.

Anyway, I do have gas service for my forced air furnace/AC unit reasonably close to the garage and several of my neighbors have gas water heaters in their detached garages. My question is, which is more efficient in all seasons, gas or electric? Thanks in advance for any advice!