Tankless vs. Tank – A Showdown in Energy Efficiency

Yank That Tank - Go Tankless


Tankless vs. Tank – A Showdown in Energy Efficiency

October is here and that means it’s Energy Action Month – an initiative put forth by the U.S. Department of Energy to educate and increase awareness of ways to improve energy efficiency and conservation. As energy conservation continues to grow in importance, Rinnai is doing its part to help homeowners and businesses bring down energy costs and improve energy efficiency. One of the simplest ways to do that is to make the switch from a traditional hot water tank to a Rinnai Tankless Water Heater.

In fact, Rinnai Tankless Water Heaters use up to 40% less energy than a traditional tank.

That sounds all well and good on the surface, but to understand where the savings are coming from, it helps to understand how a Rinnai Tankless Water Heater differs from a hot water tank.

Rinnai Tankless Water Heater vs. Tank



A standard hot water tank works by heating and reheating the water it holds to maintain the desired set temperature – regardless of usage or demand. This reheating of the same water causes an additional energy expenditure which brings down the efficiency of the product



With a super-efficient tankless water heater from Rinnai, cold water enters the unit only when hot water is needed. The water is then heated, exits the unit and travels to the location where the water is needed.  Rinnai Tankless Water Heater offers an endless supply of hot water whereas a hot water tank eventually runs out, and it does it all while using considerably less energy

Take a look at table A below on how the annual operating costs of a traditional tank and Rinnai Tankless Water Heater compare as based on the Department of Energy's 2017 findings. As you can see, Rinnai Tankless Water Heaters consume less energy therefore costing less to operate – not only saving you money but reducing your carbon footprint in the process.



Tank Technology Fuel Type/ Energy Source UEF (Uniform Energy Factor) Annual Operating Costs*
Standard 50-Gallon Gas Storage Tank Natural Gas 0.60 $309
Standard 50-Gallon Gas Storage Tank Propane 0.60 $745
Standard 50-Gallon Electric Storage Tank Electricity 0.95 $626
Tankless Technology Fuel Type/ Energy Source UEF (Uniform Energy Factor) Annual Operating Costs*
High-Efficiency Non-Condensing Tankless Natural Gas 0.81 $228
High-Efficiency Non-Condensing Tankless Propane 0.81 $552
Super-High-Efficiency Non-Condensing Tankless Natural Gas 0.92 $201
Super-High-Efficiency Non-Condensing Tankless Propane 0.92 $487
*As based on the average cost to run an electric tank water heater per the Department of Energy (DOE) Average Energy Costs (doe.gov) 2017