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Have you ever thought how much water you use using for washing dishes? Following these dishwashing practices you can become water positive.

I grew up listening to my mom saying you should never run the dishwasher unless it’s completely full. She always believed it would be wasteful to run a dishwasher with a couple of dishes inside. Instead, she said it’s better to wash them by hand in the sink to save water and energy.

This belief was only reinforced by becoming aware of our water consumption. By now, we all know we should take shorter showers and not leave the water running while washing our teeth. 

While those tips are helpful, the dishwasher situation is different. On my path to becoming an environmentalist, I had to change pretty much all of my habits and do a ton of research. 

One of the facts I was shocked to learn (and especially my mom) is that handwashing is actually more wasteful than running even a small load in the dishwasher. 

There are several ways in which you can streamline your dishwashing routine. Here are my dishwashing tips, together with all the info on why you should stop washing dishes by hand.

Dishwasher VS Handwashing: Which Dishwashing Method Saves More Water?

Here’s all the info on dishwasher vs. handwashing that I guarantee will turn you into a dishwasher convert.

How Much Water Does Dishwashing Requires?

A dishwasher is one of the largest home appliances, so many people assume it uses a large amount of water for each load.

However, that’s not the case. According to a study done by the University of Bonn in Germany, a dishwasher uses one-sixth of the water and less soap compared to handwashing.

The most important thing to consider is how old your machine is. Dishwasher water consumption depends on your machine’s manufacture year. The older the model, the higher the chance it’s more wasteful. 

When getting a dishwasher, always go for Energy Star certified ones. Energy Star has hundreds of dishwasher models in their database. According to them, dishwashers manufactured before 1994 use between 9 to 14 gallons of water per one load. 

Energy Star certified dishwashing saving

On the other hand, newer standard-size, Energy Star certified dishwashers use only 3 gallons of water per one cycle, according to the Natural Resources Defense Council. Modern machines are made to use the exact amount of water for effective dish cleaning, and they also have “half-load” and “rinse-only options” for extra water savings.

It may seem like a dishwasher is spraying water everywhere, but an Energy Star certified dishwasher can save almost 5,000 gallons of water per year. This is due to the new standards put in place in 2013 that require dishwashers to use 5 gallons per load. This is significantly less than 10 gallons of water waste per load, which is how much dishwasher units built before 1994 created.

How Much Water Does Handwashing Need?

If you’re still not convinced a dishwasher is the better option for dishwashing, here’s some handwashing info. 

A typical US sink ranges about 8 gallons. Consider how much you fill your sink when you wash dishes. A dishwasher fits 144 items. Let’s say you’re washing the same amount of dishes by hand. You’ll have to fill the sink to two-thirds or 4 gallons. This is already more than a dishwasher would use. 

Then, consider how often you change the water?

Let’s say twice. You’re now at 12 gallons of water. 

Also, if you rinse the water under a running tap, your water consumption will go sky-high. Or, do you maybe have two sinks? Then you can fill and dunk the plates in the second sink. But now you’re filling two sinks and not one, which doubles the already big water consumption.

dishwashing by hand

Another thing to consider is how long you are running cold water until it gets hot. And let’s be honest, how often do you put this water in the bucket to use it for something else instead of letting it go down the drain?

Finally, do you rinse the dishes after washing them? And, how much water is spent rinsing kitchen sponges when all the dishes are done.

Here are some numbers to consider. An average faucet flows at 2.2 gallons per minute. This means you have about 4.4 seconds of open faucet to wash and rinse each dish, assuming you’re washing 54 items of dishware.

Seeing as not many people (or any?) are this fast, washing by hand can result in 13 gallons of wasted water, compared to washing the same number of items in a washing machine.

Finally, here’s a dishwasher and handwashing comparison:

According to the study by the University of Bonn, a full dishwasher can use 3 gallons of water to clean a full load (144 items). Washing the same number of items by hand uses around 27 gallons.

The winner is clear. 

Pro tip new

Note: This is data for average water consumption. The study says water usage can go up to 116 gallons per one load when handwashing.

Dishwashing Energy Usage and Environmental Effect

According to the DOE and Environmental Protection Agency, Energy Star dishwashers use less water than handwashing the dishes. According to them, washing the dishes yourself will cost about $413 more in water and energy than using a dishwasher.

To call upon the University of Bonn study once again, the dishwasher uses only half the energy compared to washing by hand.

Let’s start with the impact of heating the water. If you use warm water for both washing and rinsing, heating 2 gallons with a gas water heater takes about 960 BTUs.

In general, gas water-heaters are 65% efficient, so it usually takes 1477 BTUs to heat the water. This amounts to 1.5% of a therm, and one therm emits 11.7 pounds of CO2. Heating 2 gallons of water with a gas water heater emits .17 CO2. 

If you have an on-demand or a tankless water heater, the numbers are a little different. They are 80% efficient, which amounts to 1200 BTUs, or 0.14 pounds of CO2.

An electric water heater uses between 86% and 93% energy for heat. This makes them less efficient at heating water. They need 28 kWh to heat 2 gallons of water, and each kWh emits 1.725 pounds of CO2. So, if you heat 2 gallons of water with an electric water heater, you’ll emit .51 pounds of CO2.

On the other hand, a modern dishwasher uses 1.59 kWh to 0.87 kWh, so they come on top once again. Because the dishwashers use less energy, they are better for the environment. 

Finally, recent research by the University of Michigan established that handwashing the dishes produces double the amount of greenhouse gasses over 10 years compared to using a dishwasher. 

Let’s talk Sanitization: Which Method Offers Cleaner Dishes?

Dishwashers are machines specifically made to clean the dishes, and over the years, the manufacturers have perfected their products. Nowadays, dishwashers come with several options, such as pre-rinse, sanitize, heated-drying, and more.

Also, dishwashers can handle much higher temperatures than our hands. Even if you use hot water to wash the dishes, it’s nowhere near hot enough to make the dishes bacteria-free. The temperature for satinized dishes should be 140 to 145 degrees, and our hands just can’t take the temperature that hot.

a modern dishwasher

Another thing to consider when washing by hand is the sponge. The sponge is one of the germiest items in our home. All the bacteria end up in tiny holes, and new bacteria grow there every 20 minutes. Rinsing the sponge isn’t enough. It should also be sanitized, but the percentage of people who really do that is very small. 

Dishwashers also use the exact amount of detergent. When handwashing, you don’t really control how much detergent you use, which can have harmful health consequences.

Finally, a dishwasher also dries the dishes, which is more hygienic than washing and drying them with a tea towel. Similarly to a sponge, a tea towel is also full of germs.

So, the dishwasher also wins this round.

How Often Should You Use Your Dishwasher?

You should use your dishwasher regularly. Unlike other home appliances, dishwashers will have a longer life and better workability if you use them often.

If your dishwasher is unused for a prolonged period of time, such as more than a few weeks, it’ll start to deteriorate. Usually, the longest time you should go without using a dishwasher is a month before problems start to arise. The most common issues are motor problems, pipe issues, dried off motor seals, pump water, even a broken machine. 

You should use the dishwasher at least once per week on a short wash. This will keep the motor seals from rusting. 

The average number of dishwashers runs in one household is five per week. This is also the ideal number for the longest dishwasher longevity. If you use your dishwasher more frequently, you risk repairs and replacements. 

For example, if you have 7 cycles a week instead of 5, you lower the dishwasher life to 7 years instead of the average 10. On the other hand, if you cut down your cycle to 5 or less than 5 per week, your dishwasher could last 12 or more years.

How to Use a Dishwasher That Hasn’t Been Used In a While

If you haven’t used your dishwasher in a while, bacteria will build-up, so you should clean it before placing the dishes in it. 

You can clean the machine in several ways:

  • Throw in a cleaning tablet
  • Add a few teaspoons of mineral oil to prevent future evaporation
  • Fill a cup with white vinegar and run a cycle — recommended especially for older machines
  • Remove the shelving and run a cycle with bleach
  • Clean the drain with a paper towel
  • Wash the filter with hot soapy water
  • Wipe the rubber seal and front

Do You Need to Rinse Dishes Before Putting Them in The Dishwasher?

No, you don’t need to rinse dishes before putting them in the dishwasher. The biggest argument for the pre-rinse is that the dishwasher isn’t powerful enough to remove food stuck to the dishes, and that food particles will clog the drain hose. 

However, the experts all agree that there’s no need to rinse the dishes. Not only is it not necessary, but it can be detrimental. Here’s why.

Dirty Is Better for the Dishwasher

If you put dirty dishes in the dishwasher, they will end up cleaner than the dishes you’ve pre-rinsed. This is because modern dishwashers have intuitive technology. 

The dishwashers made in the last decade have a soil-sensing system, which consists of a soil collector and a pressure sensor. The pressure sensor evaluates the food coming off the plate during the first rinse and then adjusts the wash. If there’s a lot of dried food, the wash pressure will increase. Some models can also increase the water temperature and use more detergent if needed.

But, if you pre-wash your dishes, the soil-sensing system will think the dishes are clean, and the items will get a light wash, which may not be enough.

Detergent Affects Dishwasher Effectiveness

Many detergents have enzymes that attach and dissolve food particles, so washing the dishes is easy. 

If you pre-rinse the dishes, there’ll be nothing for the detergent to latch on to, so the dishes may not be well cleaned.

Pre-Rinsing Contributes to Water Waste

Some studies say we spend 2 to 6 gallons of water per minute to rinse dishes. Depending on how many dishes you have, you may even waste 15 gallons of water per one load. 

Energy Star estimates that an average American household does 215 loads of dishes yearly, which amounts to 3,225 gallons of wasted water if you pre-rinse.

This is not only bad for the environment but your wallet as well.

When You SHOULD Pre-Rinse

There’s one situation when you actually should pre-wash your dishes. A pre-wash is necessary if they’ve been left for a long time before loading the dishwasher.

This goes especially for dishes coated in proteins and carbs as they tend to stick. Think food such as milk, eggs, cereal, and more. If they’re left for hours or days before washing, the dishwasher likely won’t be able to remove them.

In this situation, you should pre-wash.

7 Dishwashing Tips You NEED to Know!

These are my best tips on using and choosing a dishwasher.

1. Run a Full Load 

Your dishwasher should be at maximum capacity before you turn it on. Running a dishwasher at maximum capacity will save water, energy, and detergent.

Note: Be careful when using half-load. As the name says, it will use less energy and water, but not really half the amount compared to a full load. 

If you don’t have a full load, and you don’t want to leave your dishes on for too long, so they don’t become crusty, you should still run a dishwasher.

Even if the dishwasher isn’t full, it’ll use fewer resources compared to washing by hand.

2. Organize the Dishes Correctly

There is a right way to load the dishwasher. Don’t just stick dishes in every nook and cranny. 

There should be enough space between the dishes so each dish can get cleaned and also the dishwasher isn’t under unnecessary strain.

By not overloading the dishwasher, you’ll also be saving water and making sure each item is thoroughly cleaned. 

I place larger items at the back and sides of the rack. This minimizes the need for another wash. Otherwise, placing plates at the front may stop the water from reaching the detergent dispenser.

Check the owner’s manual if you aren’t sure how to correctly stack the dishes in your machine.

Dishwashing Tips

3. Don’t Overload the Dishwasher

I’ve talked about how important proper dish placement is for making sure each item is cleaned well. The same goes for not overloading the dishwasher. 

If your dishwasher is overloaded, it won’t run efficiently, and the dishes won’t get cleaned well. This means you’ll have to run another cycle, which is a waste of resources.

Also, frequent appliance misuse will put a strain on its parts and lead to damage. You’ll have to repair or replace your dishwasher sooner if you overload it regularly.

Make sure each item is at a safe distance from other dishes in the dishwasher. This will also prevent the dishes from breaking. 

4. Use a Good Detergent

If you’ve noticed there’s stuck food on your dishes after running the dishwasher, the detergent could be the one to blame.

This will result in more work for you, as you’ll have to either wash the dishes by hand or run the dishwasher again, which will waste more resources.

Instead, invest in a good detergent. A high-quality detergent will allow you to skip the pre-rinse and not have to wash the dishes again.

Another important detergent tip is not to overuse it. Overusing the soap will result in a pile of bubbles that erupt from the machine and go all over your kitchen. 

The excessive detergent will build up over time and can be harmful to the appliance. It’ll create a moisture build-up that’s difficult to air out, and excess soap doesn’t properly wash away.

5. Air Dry the Dishes

To use fewer resources, you can prevent the dishwasher from using electric heat to dry the dishes. 

Instead, open the door at the end of the washing cycle, so the dishes can air dry. As the water is hot. it will evaporate quickly if you open the door.

It’s estimated that you can save 15% of energy by air drying, and you’ll decrease greenhouse gas emissions by 11%.

Another good alternative to using electric heat to dry the dishes is to use the air-dry cycle. This cycle circulates the room air through the dishwasher via a fan and doesn’t need a lot of energy.

6. Scrape the Dishes Before Loading Them

You should scrape the dishes before placing them in the dishwasher. However, many people do this by pre-rinsing, and I’ve already talked about how this should be avoided.

Pre-rinsing the stuck food will only waste more water than the dishwasher and make the detergent scrubbing less effective.

Instead, remove leftover food by scraping it with a utensil into a trashcan or sink. This means the dishwasher won’t have to work so hard at cleaning the dishes.

Also, if you don’t scrape the food, you risk having a clogged appliance, which will result in more issues later on.

7. Choose a Dishwasher Wisely

I’ve talked a lot about the Energy Star rating, so by now, you know this is the certificate you should look for. 

Energy Star rated appliances use 25% less energy than the mandated minimum.

Other features to look for in a dishwasher are an adjustable upper rack, so you can fit dishes of different sizes, flatware slots so the cutlery will be separated and easier to clean, and various cycle options. This can include half-loads and eco cycles.

Finally, pay attention to the decibel rating. Usually, more affordable dishwashers tend to be noisy, which is especially bad if you live in a small apartment. My advice is to choose a dishwasher with good insulation and a Db rating. 

Don’t Have a Dishwasher? Follow These Water Saving Tips

You don’t have a dishwasher, and you’re dreading the clean-up this holiday season? I’ve got you covered. Here are the best tips to make washing the dishes a breeze and save water.

1.Let the Dishes Pile Up

If you’re anything like me, the sight of a stack of dirty dishes will send you into a cleaning frenzy. But take a deep breath and step away.

Remember your goal is to create less water waste. Wait until your party or holiday meal is done, and the guests leave before you tackle the dishes. 

It’s better to let the dishes pile up and wash them at once than to do the dishes several times a day. 

This will also save time, as you’ll only grab the gloves, detergent and clean the sink once.

2.Let the Dishes Soak

Again, I know this can be triggering if you are a clean freak, not to mention gross. 

But, it’s better to let the really dirty dishes soak than spend minutes and gallons of water under a running faucet trying to scrub them clean.

You can soak the dishes one by one or fill a sink a little and leave all the dishes in. 

Pro tip: You don’t need a full sink to soak the dishes, but fill it up just enough so the dishes are underwater.

My advice is to soak all the dishes at once instead of one by one. Do this by plugging the sink and running hot water. Only turn the faucet on again when you’re sure the dishes are ready to be rinsed.

While dishes need clean water, keeping them soaked in dishwater isn’t a health threat as long as you rinse well.

3.Get a Bucket

I know I’ve said you should fill up the sink and soak the dishes. But, if you’ve got a large sink and not that many dishes, this would be a waste of water. 

Instead, you can reduce the amount of water you use by using a bucket. Place the bucket in the sink or a tub.

Another great idea is to use a pot or a pan you just cooked in for soaking the dishes. You have to clean it anyway, so you can kill two birds with one stone. Soak the pot and the smaller utensils at the same time. 

Another way to save water with a bucket is to capture cold water while waiting for the hot one to start. Then, reuse this cold water for something else.

4.Organize the Dishes In the Sink

Organizing the dishes to save water doesn’t only work in the dishwasher but also in the sink.

Stacking the dishes inside one another is a good way to soak everything without having to fill up each bowl or glass with its own water.

Also, this is a great way to speed up the washing process, as the soap and water around the smaller dishes in a larger bowl or a pan will dissolve stuck food and make it easier to clean.

5.Don’t Use In-sink Garbage Disposals

In-sing garbage disposal is an easy way to get rid of food, but it also needs running water to operate.

Instead of the disposal, you can scrape the food into the trash or compost. This is much faster. Plus, you don’t have to worry about forgetting which food can and can’t go into the disposal, such as bones.

Finally, by scraping the food into the trash, you won’t only be saving water, but you won’t harm the disposal system or clog the drain.

Become Water Positive With a Dishwasher

There’s a lot of uncertainty and misconceptions out there about dishwashers. However, after learning they save water, energy, are better for the environment, and use less detergent, I’m inclined to believe it’s an appliance made in heaven.

After all, who likes handwashing the dishes? 

I hope I managed to convince you that dishwashers are, in fact, water positive and a better option to washing dishes by hand. 

If you don’t have a dishwasher, that’s alright. Use the tips I’ve outlined above, and you too will save water this holiday season. 

If, however, a dishwasher is on your wishlist, make sure to show all the info about how environmentally friendly they are to your loved ones. Who knows, this just might be what convinces them, and you get a new life-changing appliance this holiday season. 

Marina is passionate about sustainability and works to help ensure our planet stays as our home for a long time. She takes part in environmental conservation by recycling and not buying single-use plastic.

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