Original poster said....
"should I cut the electricity to it"
So, I am going to assume it has wires going to it. I am going to guess that if you follow those wires, they go to a plug that you would plug into a wall.
If that is also true, then, what you are looking at is a heater for the engine, when the temperature is cold out side, it is used to keep the engine warm enough to get started easy.