EPA report summary
U.S. EPA verified 75% savings of
electrical energy and greenhouse gases
The U.S. Environmental Protection Agency’s Greenhouse Gas Technology Center conducted a 15-month test of the EarthLinked® Commercial Water Heating system performance.
Click to read the full report.
The system includes:
- an EarthLinked heat pump;
- an earth loop cluster that circulates non-ozone depleting refrigerant (R-407c) in standard copper refrigeration tubing to extract heat from the shallow earth; and
- a double-walled refrigerant-to-water heat exchanger.
The test was conducted in an assisted living facility in Sun City Center, Florida. The system was connected to a standard electric water heater tank that stores the heated water. Although the tank is capable of providing supplemental heat, it was never required to do so during the test.
As hot water is used in the building, city water enters the system, passes through the heat exchanger, and is stored in the standard tank. The temperature of the city water entering the system is 72°F (22°C). The return temperature to the heat exchanger from the continuous building circulation system is 94°F (34°C), and the delivered water temperature is limited to 110°F (43°C).
That temperature was selected by the owner to comply with governmental regulation. Short-term tests were conducted to monitor system capacity and efficiency, taking the temperature up to 130°F (54°F). Comparative tests were conducted using the standard electric resistance elements of the water tank exclusively. Then long-term testing of the EarthLinked system was conducted for many months.
The EPA report verifies 75% savings of electrical energy by the EarthLinked system in comparison with electric resistance water heating. By avoiding the generation of that amount of electricity, a typical EarthLinked unit avoids the emission of 7,000 pounds of carbon dioxide and 15 pounds of nitrous oxide per ton of capacity per year, which amounts to 42,000 pounds of CO2 and 90 pounds of NOX each year by a typical 6-ton capacity EarthLinked unit. That is equivalent to not burning 3,642 gallons of gasoline or 74 barrels of oil annually.