Although dishwashers have been prevalent for well over a century, many people still rely on washing their dishes by hand, or at the very least pre-washing them before loading them into the dishwasher.
After all, many of us assume, there’s no substitute for human labour when it comes to keeping things clean.
But as modern technology has evolved, this may not hold true anymore – according to recent statistics, modern dishwashers are more efficient than ever, making them not only capable of getting your dishes cleaner than you would washing them by hand, but also wasting less energy and water.
Experts from Consumer Reports(1), the Environmental Protection Agency’s Energy Star Program(2), the Natural Resources Defence Council(3), and the American Council For An Energy Efficient Economy(4) all suggest that in most cases, the dishwasher is actually more environmentally friendly than hand-washing your dishes.
Changing Energy Standards Have Led To More Efficient Machines
What’s to credit for modern washing machines being so efficient? According to the Washington Post, constantly improving appliance standards have led to dishwashers using less and less water and energy.
“While it may be possible to use less water/energy by washing dishes by hand, it’s extremely unlikely,” said Jonah Schein, technical director for homes and buildings in the EPA’s WaterSense program(5).
But not all dishwashers are created equal. When it comes to efficiency, Energy-Star certified dishwashers appear to be in a class of their own. The average dishwasher uses 6 gallons of water per cycle; the average Energy Star-rated dishwasher uses 4 gallons per cycle.
Can Hand Washing Be as Efficient as Dishwashing?
The average faucet flows at 2 gallons per minute, so if you can successfully wash and rinse eight place settings — plates, bowls, forks, knives, spoons, glasses, etc. — and those six serving dishes that your dishwasher can handle without running the faucet for more than 2 total minutes, then, you might be better off hand-washing.
Assuming you’re washing 54 pieces of dishware (that’s 48 pieces of dishware — 6 pieces per setting — and 6 serving dishes), you’ve got about 4.4 seconds of wide-open tap water per piece, or about 9.5 ounces of water to wash and rinse each dish.
They’re Not Just More Efficient – Dishwashers Get Your Dishes Cleaner
While how clean is “clean enough” can be subjective, dishwashers have a number of advantages over hand-washing your dishes when it comes to getting dishes cleaner, too.
For starters, most dishwashers use scalding hot water to sterilize dishes – something our fragile human hands just aren’t built to take(6).
In addition, many modern dishwashers have specially designed racks and jets, as well as soil sensors which can tell when your dishes are still dirty and need extra cleaning.
To compete with these contemporary inventions, you’d need to use very little water to wash your dishes, soak them as well as scrub them, and even then, outperforming the machines is a hard feat to pull off.
And pre-washing your dishes before throwing them in the machine may not actually get them cleaner – while it does increase your water consumption by at least twice as much.
Save Time And Energy
If you’re thinking of making the switch from hand-washing your dishes to a modern dishwasher, here’s a bit of incentive:
According to Consumer Reports, households that use out-of-date models of dishwashers and compensate by pre-washing their dishes could be wasting over 22,000 litres of water per year(7).
Then there’s the time factor – how much time do you spend hand-washing your dishes? According to the Energy Star program, all that hand-washing costs you roughly 230 hours, or 10 days, each year(8) – imagine what you could do with a week and half of spare time!
If you’re concerned about your water consumption, it’s clear – one of the best things you can do is let go of the idea that you can wash your dishes better than a machine, and let the dishwasher do its job.