Dishwashers are so convenient. Rather than have to scrape off the food grime and scrub with all the elbow grease you have, you can just put your dishes in the machine and let it do the rest.
Of course, some dishes must still be washed by hand, but is this the more water-efficient method, or is the dishwasher superior?
This article will examine in detail how much water you use when you wash dishes by hand compared to running a load through the dishwasher. After reading, you’ll be ready to choose the most energy-efficient and eco-friendly option for your home!
How Much Water Does a Dishwasher Use?
Older dishwashers use between 9 and 14 gallons of water a load, whereas hand-washing dishes can use 20 gallons or more. Therefore, you’re better off using a dishwasher as often as possible. Upgrading to an Energy Star-certified dishwasher is best—these machines use only about four gallons of water a load.
Water Usage Comparison Between New and Old Dishwashers
As we touched on in the intro, a dishwasher is a godsend. You can save time spent bent over the sink, and you don’t have to touch smelly, cold food grime either.
A 2019 article in the food magazine Taste cites a statistic from the US Energy Information Administration on the prevalence of dishwashers. According to the article, about 80 million homes in the US have these appliances.
So how much water does your dishwasher use on an average cycle? That depends on its age. Let’s take a closer look.
An old dishwasher is one manufactured before 1994. If your machine is at least that old, the machine sucks up between nine and 14 gallons of water for each load of dishes.
Apartment Therapy says that the average American household uses dishwashers five times weekly. So with an older model, you’d use between 45 and 70 gallons of water per week by running the device alone.
Per month, you’re looking at a water usage rate of 180-280 gallons. And per year, it’s between 2,160-3,360 gallons.
Energy Star Dishwashers
If you upgrade to a newer model, it will automatically use less water due to the upgraded technology. Yet your best choice is to buy an Energy Star-certified dishwasher, as it will be the most energy-efficient.
As stated in the intro, an Energy Star-certified model will use four gallons of water per load or less.
To keep this example simple, we’ll just say that your new machine uses four gallons of water each time you run it.
Given that you’ll use the dishwasher five times a week, that’s 20 gallons of water per week, 80 gallons per month, and 960 gallons per year—you won’t even crack the 1,000-gallon mark with an Energy Star washer!
How Much Water Does Handwashing Dishes Use?
According to the Taste article, 20% of the 80 million US dishwashers are untouched.
Some people feel they’re contributing more to household chores if they manually wash the dishes instead of using a machine. For others, especially older folks, it could be an aversion to or confusion about newer technology.
So let’s say you scour all your dishes with a scrub brush and your own two hands. How much water does this use?
Water flows out of most sinks at a rate of 2.2 gallons per minute. So you’re already using a quarter-gallon of water just by turning on the tap for six seconds. In 20 seconds, you’ve used an almost three-quarters gallon of water.
As you can guess, it’s not going to be pretty for a full load of dishes. You’d use at least 27 gallons of water, but it can be more depending on how long you do the dishes or how many dishes you have to wash.
For instance, according to a 2021 Cision report, the average dishwash time is 25 minutes. So if you’re using 2.2 gallons of water for each of those 25 minutes, washing your dishes by hand already sucks up 55 gallons of water.
Mulberry’s Garment Care found that the average amount of time a person spends per week hand-washing dishes is six hours.
Using the 2.2 gallons a minute of water as a baseline, for each hour of dishwashing, that’s 132 gallons. So spending six hours per week at the sink would suck up 792 gallons of water.
That’s not per year, but per week!
Which Is Better for the Planet – Handwashing or Using a Dishwasher?
So now comes the big question: which is the better activity for our planet, using a machine or handwashing?
The answer is clear from the last two sections. Even if you have an older dishwasher, you’ll save more water running it than you would handwashing your dishes.
The reason is that machine washing uses only the water required to clean the load. When you wash your dishes by hand, you turn the water on and use 2.2 gallons a minute, whether you’re cleaning the dishes, putting them in the dish rack, or squirting out dish soap.
Of course, the most energy-efficient solution is upgrading to an Energy Star-certified device. You’ll use at most four gallons of water per load and possibly fewer.
We’d be remiss not to discuss the electrical load of machine washing, as that’s a factor when determining how eco-friendly something is.
A 1,200-watt dishwasher running for an hour will use 1.2 kilowatt-hours or kWh of electricity. That totals about 12 cents a load if your household is on a 10-cent-per-kWh electricity plan.
This electrical load isn’t huge, but it’s not zero either.
Handwashing will naturally use less electricity. Of course, you’ll have the lights on in your kitchen, but those likely would have been on anyway.
Scrubbing and scouring with a sponge doesn’t need any electrical power so you can save on electricity costs by handwashing dishes.
Considering the negligible electricity costs of machine washing and how much more water you save when running a dishwasher versus handwashing, we can still confidently say that machine washing is the more eco-friendly option.
Tips for Making Dish Cleanup More Energy-Efficient
Do you want to increase how green your dishwashing routine is? The following tips will help you do just that!
Only Run Your Dishwasher When It’s Full
You might think running your dishwasher when it’s half-full will reduce water usage, but that’s not true. The dishwasher will use just as much water as if it was completely full.
In the future, only run the dishwasher when both racks are fully loaded.
Wash Only the Dishes That Aren’t Dishwasher-Safe
As we hope we’ve clarified, handwashing dishes is a tremendous waste of water. You’re also wasting time—the Cision report states that the average American spends six days of their lives each year washing dishes.
To make handwashing an eco-friendlier activity, wash only the dishes that can’t go in the dishwasher and keep handwashing sessions short.
Use an All-Natural Detergent and Sustainable Sponge
The products you use when washing the dishes can also go a long way towards making our planet greener.
If you’re not already using an all-natural detergent for handwashing or the dishwasher, it’s worth switching. These products contain far fewer chemicals that can travel through the water and lead to algal blooms.
A biodegradable sponge is also a much better cleaning solution. Unlike a standard sponge, it won’t end up in a landfill. Plastic sponges never break down, while cellulose sponges will disintegrate in a year.
For every plastic sponge you use in a year, you’re contributing up to 52,000 years of landfill waste!
Machine-washing dishes saves more gallons of water than doing the same by hand. An older dishwasher is even more efficient than hand-washing, although the older machine will use more water and electricity.
Upgrading your dishwasher to an Energy Star model is the greenest solution of all, as each load of dishes will need fewer than four gallons of water to clean!