ORBEK ET011

The registry lists this unit at a UEF, the ratio of hot water delivered to energy used, of 0.94. This site computed the 628 kWh yearly figure from that UEF and the DOE test's daily hot-water draw for the very small draw pattern. The registry does not publish the yearly figure itself. The source is DOE CCD, retrieved 2026-09-19. The figure applies only to that test draw and only to electricity, so a household that draws more or less hot water than the test will use a different amount. The maximum flow rate in gallons per minute is 1.2. That is a separate rating and does not change the annual figure. The method is described on the how the annual cost is calculated page.

The ORBEK ET011 ranks 188th lowest energy use of 271 models registered as an electric tankless unit at the very small draw pattern. That places it in the second-highest quarter of its class for energy use. The class median is 615 kWh, and this model sits 13 kWh above it. The data given here do not describe how the remaining models are spread around the median, so the gap is not characterized further. The very small draw pattern covers small units, such as a single bathroom or a point-of-use heater under a sink. The 628 kWh figure is a fair comparison only for that kind of use. For a different size or fuel, the selector by fuel, space and size filters by those inputs instead.

The running cost is not written as an amount on this page because it depends on your own utility electricity tariff. Multiplying 628 kWh by your rate per kilowatt-hour gives the yearly cost at the test draw, and only at that draw. The cost calculator on your own ZIP does this with the tariff for your location. If you are comparing this unit with another model in the same class, find a same-class replacement by model number and start from ET011. A modeled installed-cost range is shown separately on the page with its own source and date, and it is not repeated here.