We know which method will give you more time to binge-watch your latest Netflix obsession, but what's better for the planet, your dishes, and your wallet?
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Solving the dishwasher vs. hand-washing debate requires considering several different facets of washing dishes. The easiest course—especially for those days when you’d much rather be spending time with that binge-worthy Netflix show—is using the dishwasher, of course, but that comes with its own worries, including a smelly dishwasher. And there’s more to the puzzle than just convenience.

We’ll start with this: There is most definitely a wrong way to wash dishes, and chances are, you’re guilty of it. “Generally, people are not efficient doing their dishes,” says green architect Colin Cathcart, of Kiss + Cathcart Architects and Fordham University, where he’s an associate professor of architecture. “When you let the hot water run and then pass the dishes underneath the water so that it goes right down the drain, that’s certainly the wrong way.”

Pitted against that kind of water-wasting hand washing, your dishwasher is always going to be the more environmentally friendly option.

“Energy-efficient dishwashers generally use less water than hand washing and less energy, too,” Cathcart says. “The dishwasher’s recirculating pump sprays a small amount of water all over the place. Both the pump energy and the water heating energy is quite minor.”

Of course, if you’re an obsessive pre-rinser, or if that frittata casserole dish comes out of the dishwasher still crusted with baked-on eggs and cheese, the efficiency level of machine-washing can plummet.

“The whole formula goes out the window if you rinse dishes first, then put them in the dishwasher, then they don’t come out clean and you have to put them through again,” says Cathcart, who points out that dairy, eggs, and oils are notoriously tough to wash away in the dishwasher. (We’ll add that avocado can be a beast as well.)

By hand-washing your dishes the correct way, says Cathcart, you might come out slightly ahead of the energy-expenditure game—if only because you’re using human energy to dry the dishes rather than the heat cycle on your dishwasher.

The how-to for the greenest-possible hand-washing (anyone without a dishwasher at all, take note): Fill half of a split sink with hot water and a small amount of low-polluting dish soap (“get the water as hot as your hands can stand”), and the other side of the sink with clean hot water. Scrub dishes on the soapy side, then rinse them in the clean side. Dry with dish towels, not paper towels (remember: the goal is green), or let air dry on the counter.

By using this hand-washing technique, you’re likely using the same amount of water as a typical Energy Star dishwasher does, around 4 gallons, says Cathcart. “The differences we’re talking about are pretty marginal,” he says.

That said, Cathcart offers one reason for picking up a sponge once in a while. “I like doing dishes manually,” he says. “I learned how to wash dishes from my grandmother, and dishwashing is a basic ritual that carries through in a family. I taught my kids how to do dishes by hand. They complained mightily while doing it, but they remember those moments today.”