RELIANCE WATER HEATERS HESF-50 1**

The 3,531 kWh figure is computed by this site, not by the registry. It combines the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw. For this model the UEF is 0.92, and the draw is the medium pattern, which stands for a typical three- or four-person household. The result holds only at that test draw. A household using more or less hot water than the test assumes will use a different amount, which is not available here. The registry inputs come from the DOE CCD, retrieved 2026-09-19. The page on how the annual energy and cost figures are calculated sets out each step.

This unit is compared with the 426 models registered as an electric tank at the medium draw pattern. Among them it ranks 213th lowest in energy use. That places it in the second-lowest quarter of its class. The rated volume is 46 gallons. The first hour rating, the gallons of hot water available in the first hour from a full tank, is 67 gallons. These figures fit a reader checking a unit for a household near the medium pattern. A reader who wants energy use below the class median of 3,531 kWh will not find it in this model. The same-class replacement search by model number finds other medium-draw electric tanks to compare.

This page gives no running cost in the text. That cost is 3,531 kWh priced at your own utility's electricity tariff, and tariffs vary by utility. The running-cost calculator for your ZIP applies your tariff to this figure. With a difference of 0 kWh from the class median, its running cost on any single tariff matches a median-use model at the medium draw. At a different daily draw, the running cost is not available here. The installed price range appears in its own block, with its source and date. It is a modeled installed-cost range, not a quote.