MRCOOL MTWH04550E

This site computed the 3,531 kWh figure; the registry does not list it. It combines the registry's UEF, the ratio of hot water delivered to energy used, of 0.92 with the DOE test's daily hot-water draw for the medium pattern. The source is the DOE Compliance Certification Database (CCD), retrieved 2026-09-19. The figure holds only at that test draw. A household that draws more hot water each day will use more electricity than 3,531 kWh. A household that draws less will use less. The registry data does not show how far real use departs from the test. The steps behind the figure are set out in how the annual cost is calculated.

The MTWH04550E has a rated volume of 47 gallons. It has a first hour rating, the gallons of hot water available in the first hour from a full tank, of 64 gallons. DOE's medium pattern stands for a typical family household on a busy morning. The unit fits homes whose peak-hour demand stays within 64 gallons. The rating does not cover a home that often needs more than that in one hour. In its class, the unit ranks 213th lowest in energy use of 426, and its gap to the median is 0 kWh. At the test draw, it uses the same energy as the median model in its class. To compare other sizes or fuels, use the selector by fuel, space and size.

The text does not state a running cost for this unit. The yearly cost of 3,531 kWh depends on your own utility's electricity tariff, and that tariff is not in the registry data. The page computes the cost from your ZIP and does not assume a rate. Enter your ZIP in the cost calculator for your own ZIP. The result carries the same condition as the energy figure: the medium draw pattern at the federal test's daily draw. The installed price in its own block is a modeled range, not a quote, with its source and date beside it. If you are replacing this unit, the same-class replacement search by model number lists other electric tank models at the medium draw pattern.