While many of today’s modern water heaters can be as energy-efficient as or more energy-efficient than a tankless model, many older models are essentially outdated compared to today’s modern on demand water heaters. Typically wasting about 20 percent of the energy they consume through heat loss-AKA standby loss, an outdated water heater can easily be replaced with a tankless model or on demand water heater.
In older water heaters, the water is heated up as it fills the tank. Heat loss occurs through the sides of the tank and is lost. The water needs to be constantly reheated-especially in colder climates-and accounts for 20 percent of the energy they consume.

An instant, on demand or tankless water heater will consume no electricity or gas until they are needed. As cold water flows into the on demand water heater, a check valve alerts the heating device that water needs to be heated. Water can be heated to 120 degrees or more in as little as a second or two. This provides the ultimate in green water heating technology.

The real amount of energy savings is dictated by the amount of hot water your home and families use. For instance a smaller household of two or less people use roughly 40 gallons of hot water daily with a conventional water storage heater. This can be reduced to half the water use and a 25%+ in energy savings daily.

A larger household uses more water-let’s say double the amount. AT an 80 gallon a day rate, savings calculate to about 10%+- each day. Why such a big difference? Because a constantly used water heater has less standby loss due to the constant recycling of water through the heater.

Know your peak use and GPM rate before you buy any water heater. This can help gauge what model water heater is best for you and your family. Check out Consumer Reports Website to calculate your homes GPM and get more information on choosing the greenest water heater available.