Use your dishwasher instead of hand washing dirty dishes and save energy and money on both heating and water costs; the dishwasher uses 50 percent less energy to heat the water and 75 percent less water than washing by hand.
The cost of heating the water in your home is typically between 13 and 20 percent of your utility bill and most likely your third largest household energy expense. Because it takes a lot of energy to heat the water in your hot water tank, every time you run hot water in your sink to wash dishes you are using approximately twice as much energy as your dishwasher would. The dishwasher heats the water from within rather than using hot water from your water tank, which makes it far more energy efficient. In addition, the amount of water you use to wash by hand is on average 20 gallons, according to the American Water Works Association, but the newer and more efficient dishwashers use only about 5 gallons per load. So, by using your dishwasher, you save money on both energy and water costs, especially if it the washer is a more recent model. But be sure to run the dishwasher only when full or you drastically reduce your savings.
ADDED BENEFIT: Your dishwasher not only uses 50 percent of the energy and a significantly smaller amount of water, it uses less soap—and gets your dishes cleaner—than does hand washing.
TIP: Don’t forget to put your dishwasher on “air dry” mode if you have the option (instead of “heat dry”) to save even more energy—and money.