If you have an electric water heater, you can save an additional 5%-12% of energy by installing a timer that turns it off at night when you don't use hot water and/or during your utility's peak demand times. You can install a timer yourself. They can cost $60 or more, but they can pay for themselves in about 1 year. Timers are most cost effective if you don't want to install a heat trap and insulate your water heater tank and pipes. Timers aren't as cost effective or useful on gas water heaters because of their pilot lights.