You can reduce the amount of electricity your freezer uses by making you own freezer wrap.
By some of the reflective bubble wrap from lowes, home depot or the hardware store, the same kind you would use to wrap a hot water heater to keep it warm.
It is actually an insulator, which means that it will help insulate your freezer and keep it colder without having to work as hard.
Wrapped the sides of the freezer, being sure to keep the freezer engine area clean by cutting out the wrap around it. Then fit a piece for the top, and you can easily duct tape the top piece to the back edge of the sides, so it can work like a hinge as well.