A. O. SMITH ENJB-40W 1**

The registry lists a UEF, the ratio of hot water delivered to energy used, of 0.91 for this model. The registry does not publish annual energy directly. This site computed 2,466 kWh from that UEF and the DOE test's daily hot-water draw for the low draw pattern. The figure comes from DOE CCD, retrieved 2026-09-19. It applies only to electricity at that test draw, so a household that draws more or less hot water will see a different total. The steps behind the calculation are described in how the annual cost is calculated.

Among the 163 models registered as an electric tank at the low draw pattern, this model ranks 88th lowest in energy use. Ranks run from lowest to highest energy use, so a lower rank number means less electricity at this draw. Its 2,466 kWh is 27 kWh above the class median of 2,439 kWh, which places it in the second-highest quarter of its class for energy use. The comparison covers only models registered with the same heater type and draw pattern. The registry data does not show how this difference would appear in a particular home's metered use.

The figure belongs to the low draw pattern, a one- or two-person household. Use by a larger household falls outside the test behind 2,466 kWh, and energy use for that case is not available here. The first hour rating, the gallons of hot water available in the first hour from a full tank, is 38 gallons, and the rated volume is 35 gallons. This page does not judge whether those ratings meet a given household's demand. Running cost depends on your own utility electricity tariff, so no amount is written in this text; the cost calculator on your own ZIP applies your rate to 2,466 kWh. An installed price range is not published, because this model's ratings lie outside the range the cost database's model was fitted on. To compare units in the same class, find a same-class replacement by model number.