Unfired storage tanks shall be tested according to the instructions in section 4.2.1 334 and electric storage water heaters shall be tested according to the instructions in section 4.2.2.
Two technologies widely used for this purpose are storage heaters and hot water cylinders. Electricity is stored in the form of thermal energy during night and released during the day to provide space heating and hot water respectively.
To decrease the workload of testing personnel and improve the testing efficiency, an automatic testing system for evaluating the energy efficiency performance of electric storage water heaters has been designed.
DOE has expanded the test procedure scope to include electric instantaneous water heaters, water heaters with between 2 and 20 gallons of storage volume, and gas-fired and oil-fired storage water heaters with storage volumes up to 120 gallons.
This study assessed the operation of an electric storage water heater in a private central system. It is composed of a tank with cold water inflow connections, hot water outflow, an electrical resistance inside it and a thermostat.
The platform can carry out the standard thermal and energy storage performance test for the solid electric heat storage device by improving the test procedures of GB/T 39288—2020 combined with the heat release testing under both non-heating and heating states.
Storage heaters BSRIA has facilities and expertise for testing electric high heat retention storage heaters accordance with EN60531:2000.
State-of-charge temperature and climate tests are carried out routinely to test the safety, reliability and performance of energy storage devices. Depending on the testing task, it might also be important to carry out further tests.
This paper sets out the methodology used to determine the energy performance of storage heaters within the Home Energy Model core engine.
The previous (prior to 2014) version of the water heater testing standard for residential water heaters is defined in 10 CFR 430, Subpart B, Appendix E of the Federal Register and commonly referred to as the Energy Factor test (U.S. Department of Energy, 2010).
THE PROPOSED TEST PROCEDURE DOE has expanded the test procedure scope to include electric instantaneous water heaters, water heaters with between 2 and 20 gallons of storage volume, and gas-fired and oil-fired storage water heaters with storage volumes up to 120 gallons.
For storage water heaters, the proposed first-hour rating test is generally conducted in the same manner as the current test procedure, but the target set point temperature is now 125°F and water draws are terminated when the outlet water temperature drops 15°F from its maximum value instead of 25°F.
The energy factor and first hour rating tests specified by the current test procedure are not applicable for three small storage water heaters, labeled in this study as S-E-4, S-E-5, and S-E-6, and thus comparisons between their measured energy factors under the current test procedure and the proposed test procedure cannot be made.
1.1. CURRENT TEST PROCEDURE The current DOE test procedure for residential water heaters (10 CFR 430, Subpart B, Appendix E) provides test protocols for storage water heaters to be tested for a first-hour and energy factor rating, and for instantaneous residential water heaters to be tested for a maximum gpm and energy factor rating.
The current test procedure for commercial water heaters is specified at 10 CFR 431.106 and references the American National Standards Institute (ANSI) Z21.10.3-2011, “Gas Water Heaters, Volume III, Storage Water Heaters with Input Ratings above 75,000 Btu per Hour, Circulating and Instantaneous.”
3.1.1 Introduction A storage heater is an electric heating device that stores thermal energy during low electricity demand periods, usually at night, and releases the heat stored when required during the day. They are also known as “night storage heaters”.
