Rheem SPEX90

This site computed the 615 kWh figure. It was not taken directly from the registry. It combines the registry's UEF, the ratio of hot water delivered to energy used, of 0.96 with the DOE test's daily hot-water draw for the very small pattern. The source is the DOE CCD, retrieved 2026-09-19. The comparison group is the 271 models registered as an electric tankless unit at the very small draw pattern. Within that group, the SPEX90 ranks 77th lowest for energy use. That rank puts it in the second-lowest quarter of its class. Its difference from the class median of 615 kWh is 0 kWh. At the test draw, its annual energy use is therefore neither above nor below the class median.

The very small draw pattern covers small units that serve a single bathroom, or a point-of-use heater under a sink. The SPEX90 lists a maximum flow rate in gallons per minute of 0.9. The 615 kWh figure holds only at that pattern's test draw. The registry data gives no energy figure for heavier daily hot-water use, so that value is not available here. Demand above 0.9 at once is more than the listed maximum flow rate allows. To compare units of other fuels or sizes, use the selector by fuel, space and size. To find another model in this same class, search same-class replacements by model number.

No running cost is written in this text. The cost of 615 kWh a year depends on your own utility electricity tariff, and the registry data does not include that rate. The page computes the cost from your ZIP instead. You can also enter it in the cost calculator for your own ZIP. The inputs and steps are described in how the annual cost is calculated. Any cost result applies to the very small draw pattern at the test's daily draw, not to heavier use. The installed price range appears in its own block, with its source and date. It is a modeled installed-cost range, not a quote.