Challenge: Purchase a Tankless Water Heater

Purchase a Tankless Water Heater


A tankless or demand water heater provides hot water only when you need it, which is an efficient way to heat water and can save you money. In contrast, a storage water heater uses 15% to 30% of its energy keeping water hot 24 hours a day, whether you need hot water that often or not.


What You Should Know

  • The flow rate of a tankless water heater is limited by the system's hot water output. As a result, installing two systems to handle multiple uses for large households (for instance one system is dedicated to showering, the other for kitchen and laundry appliances) is recommended.
  • According to the US Department of Energy, "for homes that use 41 gallons or less of hot water daily, demand water heaters can be 24%–34% more energy efficient than conventional storage tank water heaters. They can be 8%–14% more energy efficient for homes that use a lot of hot water—around 86 gallons per day."
  • You may need to have a larger gas supply line and a larger vent pipe for your tankless hot water heater, so make sure you check on the requirements before you purchase one. Tankless hot water heaters can also be used with a solar hot water system, but must be specified as such before purchase.


Easy Things You Can Do

Learn more about demand water heaters to identify the best type for your needs. Visit the US DOE's website for more information.

Buy a tankless water heater to replace your old, worn-out hot water heater and save 30% on your energy usage. While these systems cost more than storage water heaters initially, you'll achieve greater savings over the long term from the reduced amount of energy they use to supply on-demand hot water. Tankless hot water heaters are available at larger appliance stores and Home Depot.

Caution: Tankless hot water heaters never run out of hot water, but don't use that as an excuse to take longer showers or linger over your dishes when washing them by hand, or all your energy savings will go down the drain.

Source: 30 Simple Energy Things You Can Do To Save The Earth (The Earth Works Group and PG&E), U.S. DOE Energy Efficiency and Renewable Energy: http://www.energyguide.com, Acterra (David Coale)