Important! Rocky Mountain Power's planned changes to the energy efficiency program became effective September 3, 2018. Changes include streamlining incentive tables to only include measure offerings and maximum incentive levels. Qualifications for energy efficiency measures going forward will be maintained on the wattsmart Homes program website. For questions or additional clarification, please email [email protected].

Energy Factor (EF)

Energy Factor, or EF, is the energy performance metric used for electric water heaters. The higher the EF, the more efficient the electric water heater. To look up your electric water heater’s EF, visit the ENERGY STAR® website.

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