Depending on which model of tankless water heater you purchase, and
what size storage tank you have now, and if it runs on gas or
electricity, you could save anywhere from 5% to 69% off your hot water
heating bill. How? Most homes use hot water for a cumulative total of
about one hour per day, yet they typically keep 40 or 50 gallons (often
times more) of water hot 24 hours a day. Having a system that
eliminates the storage and heats water only as you use it can
dramatically reduce your energy consumption.