6 Energy Saving Tips for the Dishwasher

Adapted from Consumer Guide to Home Energy Savings, by Alex Wilson, Jennifer Thorne, and John Morrill.

Whether buying a new dishwasher or using an existing one, you may be able to save a considerable amount of energy by changing the way you operate it.

Here are six tips on how to save energy:

1. Use energy-saving cycles whenever possible.

2. If your dishwasher has a booster heater, turn down your water heater thermostat. Most dishwasher booster heaters can raise water temperature at least 20 F, so a setting of 120 F for your water heater should work fine. The washing cycle will take longer if the dishwasher has to boost the temperature, but unless you need to wash several loads in a row, this shouldn’t be a problem.

3. Use the no-heat air-dry feature on your dishwasher if it has one. If you have an older dishwasher that doesn’t include this feature, you can turn the dishwasher off after the final rinse cycle is completed an open the door to allow air drying. Using the no-heat dry feature or opening and air drying the dishes will increase the drying time, and it could lead to increased spotting, according to some in the industry. But try this method sometime to see how well it works with your machine.

4. Don’t pre-rinse dishes before putting them in the dishwasher. Modern dishwashers do a superb job of cleaning even heavily soiled dishes. Scrape off food and empty liquids—the dishwasher will do the rest. If you must rinse dishes first, at least use cold water.

5. Wash only full loads. The dishwasher uses the same amount of water whether it’s half-full or completely full. Putting dishes in the dishwasher throughout the day and running it once in the evening will use less water and energy than washing the dishes by hand throughout the day.

If you currently wash dishes by hand and fill sinks or plastic tubs with water, it’s pretty easy to figure out whether you would use less water with a dishwasher. Simply measure how much water it takes to fill the wash and rinse containers. If you wash dishes by hand two or three times a day, you might be surprised to find out how much water you’re currently using. Whether or not you will save energy by switching from washing-by-hand to using a dishwasher depends on both the dishwasher and how you wash the dishes by hand.

6. Load dishes according to manufacturer’s instructions. Completely fill the racks to optimize water and energy use, but allow proper water circulation for adequate cleaning.