Ruud XE50T12CS55U1

This site computed the 3,531 kWh figure. It is not taken from 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 the medium draw pattern. For this model the UEF is 0.92. The figure therefore holds only at that federal test draw, and the fuel it counts is electricity. It does not describe a household whose daily hot-water use differs from the test draw. The registry values come from the DOE Compliance Certification Database, retrieved 2026-09-19. You can see each step of the conversion in how the annual energy and cost are calculated.

The class is the 426 models registered as an electric tank at the medium draw pattern. Within that class, this unit ranks 213th lowest in energy use. Its figure sits on the class median of 3,531 kWh, a difference of 0 kWh. The first hour rating, the gallons of hot water available in the first hour from a full tank, is 63 gallons. That rating comes from a rated volume of 45 gallons. A plumber or seller checking a same-class swap can compare these two values with the unit being replaced. Use find a same-class replacement by model number to look up models in this class. If a household needs more than 63 gallons in its busiest hour, this rating does not cover it.

This text gives no running cost for the 3,531 kWh a year. That cost depends on the reader's own utility electricity tariff, and this page does not estimate it. The cost calculator on your own ZIP applies your local rate to this model's figure at the medium draw pattern. The installed-cost block on this page is a modeled range, not a quote, and carries its own source and date. Some things are still unknown here: this unit's energy use under your household's actual hot-water pattern, and your tariff until you enter a ZIP. A comparison with another model holds only when both figures use the same draw pattern and the same UEF-based method.