We love hearing from you, and we read every one of your messages—even if we don’t always have time to reply to every one. So we’re sharing our answers to questions that have takeaways everyone can use. Got something you’d like to throw out there? Shoot us a note.
What’s your take on dishwashers? It seems to me that the energy used is unjustified when hand-washing is much better for the planet.
In the dishwasher versus hand-washing debate, the dishwasher wins. A 2020 University of Michigan study found that dishwashers used roughly half the water (16,300 gallons vs. 34,200 gallons) and produced fewer emissions (2,090 kilograms vs. 5,620 kilograms) than hand washing over a 10-year period. The difference maker: The energy used to heat up all that water.
There are a few key rules to follow to ensure your dishes are cleaned efficiently and sustainably: Use a high-efficiency model like one that’s earned an Energy Star seal, refrain from pre-rinsing, run full loads, and skip the heated dry function—which, by some estimates, can account for 15% of each load’s energy drain.
If your overall goal is to cut the planetary impact of your washing routine, it’s also worth paying attention to the type of dishwasher detergent you use. We recently tested dishwasher tablets and recommended one in particular that’s made from clean ingredients, left load after load of dishes sparkling, and is produced by a company that scored high marks in our sustainability assessment.
If washing by hand is the best (or only) option in your home, that same University of Michigan study found that a two-basin method can cut emissions and water use. In it, dishes are soaked and scrubbed in hot water in one vessel and then rinsed in cold water in another. In that setup, manual dishwashing produced fewer greenhouse gas emissions than any other method in the study, netting emissions 18% lower than even the idealized machine-washing scenario. Washing by hand is also cheaper—though the authors note that it does eat up significantly more time.