ARISTON ENS40H-DR***

The figure of 3,531 kWh is not a registry entry. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used, which is 0.92 for this model. It also used the DOE test's daily hot-water draw for the medium draw pattern. The source is the DOE CCD, retrieved 2026-09-19. The figure describes energy use under that test condition only. A household that draws more or less hot water than the test will use a different amount. The steps of the calculation are set out in how the annual cost is calculated, so you can check the arithmetic yourself.

The comparison group is the 426 models registered as an electric tank at the medium draw pattern. This unit sits at the class median of 3,531 kWh, with a difference of 0 kWh. Its rank of 213th lowest places it in the second-lowest quarter of the class for energy use. That comparison covers energy only and says nothing about capacity. For capacity, the registry lists a first hour rating, the gallons of hot water available in the first hour from a full tank, of 58 gallons. The rated volume is 36 gallons. The figures fit a household whose demand is near the medium draw pattern. For a household with a much larger morning peak, this page cannot say whether the unit is enough; the selector by fuel, space and size allows a wider comparison.

The running cost is not written here because it depends on your own utility electricity rate. Multiplying 3,531 kWh by that rate gives the yearly cost at the test's draw pattern. The cost calculator on your own ZIP does this for you. The modeled installed-cost range appears in its own block with its source and date. It is a modeled range, not a quote. Metered use of an individual ARISTON unit in a home is not available in the registry data, so actual consumption is unknown. If you need a unit of the same class, you can find a same-class replacement by model number using ENS40H-DR***.