Report Compares Propane Tankless to Electric Heat Pump Water Heaters
Sep 29, 2011
 Print this page

A new report prepared by Newport Partners the Propane Education & Research Council purports to find that propane tankless water heaters are a better option than heat pump water heaters (HPWHs) in five areas:
• energy source
• economics
• installation requirements
• hot water delivery rates
• carbon dioxide (CO2) emissions

Energy Source. HPWHs have high efficiency ratings, but the council notes that the electricity generation results in significant CO2 emissions. The council said comparable propane systems emit less than half the greenhouse gases as electric systems to produce the same amount of energy.

Economics. The council said heat pump water heater costs about $40 less per year than a propane tankless water heater to operate. It reported, however, that installation can cost $400 to $650 more, which can make the Annual Cost of Ownership (initial cost, spread out over the system's service life, and its annual energy cost) higher for HPWH.

The Newport Partners report used the following estimates of average service life:
• propane tankless unit: 20 years
• storage tank system: 13 years

Installation Requirements. The council listed the following advantages of propane tankless systems installation:
• it can be inside or outside
• it can be used as a central system or point-of-use
• it saves space compared to HPWH units

The council also noted that HPWHs require installation in locations that remain in the 40°F to 90°F range year-round. The council noted that a tankless unit has a dedicated air intake and exhaust, while an HPWH exhausts cool air into the home, which may add to home heating costs

Hot Water Delivery Rates. The council said tankless systems deliver triple the hot water flow rate, on average, compared to HPWHs.

However, the Newport Partners report, "Comparing Residential Water Heaters for Energy Use, Economics, and Emissions," showed that the HPWH had a First Hour Rating of 67 gallons, as did other storage water heaters analyzed: propane standard efficiency, electric standard efficiency, and non-condensing propane high efficiency.

CO2 Emissions. The Newport Partners report estimated CO2 emissions for a propane tankless unit are 33% lower that for an HPWH.

Back to Breaking News