Home > Products > Appliances > Dishwashers > Key Product Criteria

Dishwashers Key Product Criteria

Equipment Criteria
Dishwashers At least 41% more energy efficient than minimum federal government standards
STANDARD1 SIZED MODELS
Criteria/Product Type Current Criteria Levels August 11, 2009 January 1, 2010 July 1, 2011
ENERGY STAR EF >= 0.65 <= 324 kWh/year
<= 5.8 gallons/cycle		 <= 307 kWh/year
<= 5.0 gallons/cycle
Federal Standard EF >= 0.46 <= 355 kWh/year
<= 6.5 gallons/cycle
COMPACT2 SIZED MODELS
Criteria/Product Type Current Criteria Levels August 11, 2009 January 1, 2010 July 1, 2011
ENERGY STAR EF >= 0.88 <= 234 kWh/year
<= 4.0 gallons/cycle		 <= 222 kWh/year
<= 3.5 gallons/cycle
Federal Standard EF >= 0.62 <= 260 kWh/year
<= 4.5 gallons/cycle

1Standard (>= 8 place settings + six serving pieces)
2Compact (< 8 place settings + six serving pieces)

The current ENERGY STAR criteria for dishwashers became effective January 1, 2007. This criteria is at least 41% above the federal standard and applies only to models manufactured after January 1, 2007.

Energy Performance Metric

Energy Factor (EF) is the dishwasher energy performance metric. EF is expressed in cycles per kWh and is the reciprocal of the sum of the machine electrical energy per cycle, M, plus the water heating energy consumption per cycle, W.

EF =     1    
M + W

This equation may vary based on dishwasher features such as water heating boosters or truncated cycles. The greater the EF, the more efficient the dishwasher is. The EF is the energy performance metric of both the federal standard and the ENERGY STAR qualified dishwasher program. The federal EnergyGuide label on dishwashers shows the annual energy consumption and cost. These figures use the energy factor, average cycles per year, and the average cost of energy to make the energy and cost estimates. The EF may not appear on the EnergyGuide label.

Test Criteria for ENERGY STAR Qualified Dishwashers

Dishwasher manufacturers must self-test their equipment according to the new DOE test procedure defined in 10 CFR 430, Subpart B, Appendix C. This DOE test procedure was announced on August 29, 2003, and all models must be tested using the new procedure by February 25, 2004.

This test procedure establishes a separate test for soil-sensing machines. Included in the final rule was a decision to add standby energy consumption to the annual energy and cost calculation, but not to the energy factor calculation. Also, the average cycles per year has been lowered from 264 cycles per year to 215 cycles per year.