For Electric & Natural Gas Customers
Unless your natural gas or electric water heater's storage tank already has a high R-value of insulation (at least R-24), adding insulation can reduce standby heat loss in water heating costs. If you don't know your water heater tank's R-value, touch it. A tank that's warm to the touch needs additional insulation to save natural gas and electricity.
If you install a water heater blanket on a gas water heater, be sure to follow all manufacturers' safety instructions and precautions, as directed.
The link provided below goes to a web page with a video mainly produced by third parties to educate a public audience.