Quick Tip: Dishes – Handwash or Machine Wash? MyZA

There has long been a debate over what method of dish washing has the lowest environmental impact: hand washing or using a dishwasher. The consensus is that dishwashers are the better choice because they most efficiently use water, using an average of 22 litres of water – or only 7.5 to 15 litres for Energy Star efficient models – per full load, whereas hand washing consumes 7.5 litres of water for every minute the tap is running and far more soap.

Dishwasher energy consumption can be reduced by turning off the dishwasher after the final rinse and before the drying cycle. The clean dishes can then be wiped with a dry cloth.
Fill the dishwasher completely before operating. Partial loads waste electricity and water.
Short wash cycles, rinse-only cycles, mid-cycle turn-off, and other features are designed for energy conservation as well as convenience.
Connect your dishwasher to COLD water supply unless otherwise directed. Normally only one wash and one final rinse cycle requires hot water which is heated by an element in the dishwasher.
The dishwasher filters must be kept clear of debris. A blocked filter reduces efficiency and wastes energy.
Proper loading is important for the dishwasher to work efficiently.
Use a dishwasher that has an “AIR DRY” option.
Try to find a unit that has a high temperature setting that can be disabled with a switch.

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Dishwashers use less water (and less hot water) than using a sink.

The key is buying a dishwasher that is not an energy pig and realizing you will only be able use during the “good times”. The good times are those times when the batteries are full and the sun is still shining or the wind is still blowing. Using your dishwasher when the batteries are low means more generator time and more fuel consumed.

A decent dishwasher will use less than 1kWh per load. If you turn off the water heating element and electric drying element, a dishwasher will consume closer to 500 watt hours per load, not including the energy required to pump and heat the water.

The ENERGY STAR Most Efficient list for 2021 lists the Miele G 6935 SCi dishwasher as the most energy efficient dishwasher with a projected Annual Energy Use (kWh/yr) of 199 kW and with a projected 11.25 litres of water use per cycle.