According to Energy Star, using an energy star dishwasher uses less than half as much energy as washing dishes by hand and save nearly 5,000 gallons of water a year.

This past May, the Huffington Post discussed an article by Pablo Paster in EatingWell Magazine May/June issue, who reported on a study out of the University of Bonn in Germany, finding washing a load of dishes (12 place settings) by hand uses and average of 27 gallons of water and 2.5 kilowatt-hours of energy to heat the water (the equivalent of running a hair dryer for two and half hours!).

It goes on to say, “by comparison, an energy-efficient dishwasher uses about four gallons of water and 1 kWh of energy per load. (And over the course of a year, using the dishwasher saves more than 400 hours of labor!) Researchers also found that dishwashers cleaned better, as half of the hand-washers failed to reach an “acceptable level” of cleanliness.”

If you do not have an Energy Star dishwasher, your dishwasher most likely uses 6 gallons of water.  The water aerator in your kitchen faucet (hopefully you put in a low flow one from an earlier One Change post!) determines how much water runs (a standard aerator (not low-flow) is most likely 2.5 or 2.0 gallons per minute), so you can do the math to compare the efficiency.

Additional suggestions:

• Scrap your plate before loading in the dishwasher.
• Rather than pre-rinse all the dishes, put the dirty dishes in your dishwasher, if the dishwasher doesn’t clean it properly, hand wash the plate after it’s been through the dishwasher.
• Run only full dishwasher loads.
• Skip the heat drying and let your dishes dry on their own to save additional energy.

Look forward to discussing greening your hand washing of dishes on another “One Change” day. 🙂