A Simple Guide to Your Dishwasher’s Energy Consumption

Is it more environmentally friendly to wash dishes manually, or is using the dishwasher the greener way to do it? Washing dishes by hand may seem like a great way to push your energy consumption goals. However, contrary to what you may believe, using the dishwasher can help you minimize your water usage. 

An increasing number of people are becoming aware of the state of the environment, and most want to do their share to help the planet. If you’re one of them and are looking to live a more sustainable life, reducing your water and energy consumption is the first step. 

Knowing how much electricity dishwashers consume lets you determine which is the eco-friendlier way of washing dishes. As such, you can use the method that best suits your objectives. 

Dishwasher Electricity Usage 

So how much electricity does a dishwasher use, and how much does it add to your energy costs? As with many appliances and other electrical devices, the answer depends on several factors. These include how often you use the machine, the cycle you use, the time of day you turn it on, your energy provider, and your dishwasher model. 

Dishwasher Wattage

Your dishwasher’s wattage naturally affects its energy consumption. In general, an average dishwasher consumes between 600 and 2,500 watts. Older models are typically less energy-efficient, and their usage tends to fall on the higher end of this range. 

Meanwhile, modern dishwashers often have lower energy consumption, which helps reduce your energy costs. So how many watts your unit uses will depend partly on its make and model. 

The components that require the most electricity are: 

• The heater: This accounts for around 84% of the unit’s total wattage. 
• The motor: About 14% of the dishwasher energy consumption goes to this component. 
• The drain pump: Approximately 2% of the appliance’s total wattage is consumed by this component. 

Dishwasher kWh

The wattage only tells you how much energy your unit can potentially consume. To get a clearer idea of how much electricity a dishwasher uses, you’ll also have to look at the electricity it drains over time in kilowatt-hours (kWh). 

On average, dishwashers use about 1.17 kWh of electricity per cycle. That translates to around 20.98 kWh per month and 251.81 kWh per year. That’s based on the assumption that the electrical appliance underwent 215 cycles in one year. 

To fully determine a dishwasher’s base electricity usage, let’s look at how much electricity a dishwasher uses in greater detail. 

Per Cycle

How long a dishwasher cycle takes varies, with 2 hours being the norm. Take note, though, that the cycle length also depends on your machine’s make and model. A standard cycle usually lasts longer on more modern machines compared to their older counterparts. That’s because newer dishwashers were designed to be more energy-efficient. It might not seem logical, but longer cycles help save on water and energy consumption. 

An average dishwasher usually has 3 cycles: 

• A light cycle for delicate plates and glassware 
• A medium cycle for ordinary plates and cutlery 
• A heavy cycle for utensils that require more intensive cleaning 

Each cycle differs in length and temperature, so how much energy dishwashers use will depend on the cycle you run it. This electrical appliance consumes about 1.17 kWh per cycle. To account for the energy usage of the different cycles, estimate the unit’s kWh consumption to fall between 0.526 kWh and 1.256 per cycle. Studies further show that 1.256 kWh is the most common dishwasher energy consumption. 

Per Year

Again, the energy dishwashers use in a year will fluctuate based on the factors we’ve already mentioned. On average, a dishwasher’s energy usage stands at 251.81 kWh a year. But because people use different cycles, you can estimate the power consumption to fall between 113 kWh to 270 kWh a year, with 270 kWh being the most common power usage. This calculation is based on 215 cycles per year. 

Per Month

Dishwashers use an average of 20.98 kWh a month, although the kWh usage falls between 9.42 kWh to 22.5 kWh to account for the different cycles used. The 22.5 kWh range is the most common average usage. This estimate is based on 215 cycles per year. 

Energy-Efficient Dishwashers

Purchasing energy-efficient dishwashers will give your energy conservation efforts a boost. Fortunately, newer models have become much more efficient than their older counterparts. In the past, average dishwashers required around 10 gallons per cycle. Today, some need as little as 2 gallons to do the job of cleaning your dishes. However, the criteria used to consider a dishwasher as energy-efficient include not just the amount of water it uses. The unit must also save energy. 

Consider an Energy Star model if you’re shopping around for a replacement. An Energy Star-certified dishwasher is your assurance that you’re getting an energy-efficient unit. That’s because before a dishwasher obtains the Energy Star certification, it needs to undergo standardized testing and pass the criteria set by the program. The same applies to other household appliances.

Using a decent energy-efficient dishwasher with the Energy Star seal will save you around 3,870 gallons of water over its lifetime. It can also put $35 back into your pocket from the reduction in your energy expenses.  

Dishwashers vs. Washing by Hand

You might think that hand washing dishes uses less water. You’re wrong. Modern dishwashers use roughly between 3-4 gallons of water per cycle. Meanwhile, hand washing consumes up to nine times more than that. So wash your dishes with a dishwasher if you have one. It will help you save energy and lower your water consumption, especially if you have an energy-efficient model. 

Best Time to Use Your Dishwashers

Some factors play a role in determining the best time to run your dishwasher. These include the noise level, your other activities, and the time electricity is cheapest.  

• The noise level: Dishwashers create some noise. Some worry about using the dishwasher at night because those decibels coming from the machine may seem louder when everything’s all still and quiet. During the day, the sound gets easily drowned out by other noise. 
• Your other activities: Are you the type that gets easily distracted by the muted roar your dishwasher makes? Then, better do the dishes when you’re not busy with tasks that require your total concentration.. 
• The energy costs: Even if you already use an energy-efficient dishwasher, you can still save a few cents on your energy bill. Depending on your energy provider, electricity rates may be cheaper during certain times of the day. Since dishwashers use quite a number of kWh, the few centavos you save from the per kWh rate can add to a significant amount over time.

Dishwasher’s Water Consumption

How much water a dishwasher uses depends on the make and model of the appliance. Still, an ordinary machine consumes less water than hand washing the dishes.  

Older dishwashers, or those manufactured before 1994, waste plenty of water. They run through 10-15 gallons per load. 

Federal mandates sought to curb water wastage by imposing limits on how much water a dishwasher uses. Models made in the country after May 30, 2013, need to meet the implemented federal specifications. The unit should consume only 5 gallons max per cycle for a standard-sized model. 

Meanwhile, an Energy Star-certified dishwasher can use only a maximum of 3.5 gallons per cycle for a standard-sized model. A compact dishwasher must be able to do its job while consuming only 3.1 gallons. 

Tips on Conserving Energy When Using Dishwashers

No matter how many watts your appliance uses, running the machine will still increase your electricity bill. Even the most efficient dishwashers will consume electricity. But you can lower your power expenses if you employ some energy conservation techniques. 

Don’t pre-rinse

Today’s dishwashers do an excellent job of cleaning even heavily soiled dishes. So skip the pre-rinse cycle and just scrape off food debris and dispose of the liquids from cups and glasses. If you feel you must pre-rinse, use cold water to waste as little energy as possible. 

Dial down the heat level

Most dishwashers are equipped with booster heaters to further heat water coming from your hot water tank. That’s a redundancy you can work around. Set the tank’s thermostat to 120 degrees to save on electricity and still have clean dishes. As 80% of the energy spent by the machine goes to heating water, you can save quite a sum by using this technique.

Air dry your dishes

Letting the dishwasher use heat to dry your dishes adds to the energy your machine consumes. Simply open the door at the end of the cycle while the dishes are still hot and let them air dry. By not using the heated drying cycle, you can reduce power consumption and save money.  

Run with a full load

Your dishwasher uses the same amount of water and energy for each load, whether it’s full or only half-full. So wait until you have a full load before running your machine. This is a practical way of making the most of the water, detergent, and energy spent on dishwashing. You can save around 1000 gallons of water per month if you run your machine only on a full load.

Choose your machine wisely

The dishwasher’s make and model affect its power consumption. Older models use more energy than newer ones. Opt for one with the Energy Star seal if you’re looking for a unit that uses as little energy as possible. Appliances bearing this seal drain 25% less electricity than conventional models. You can get $40 from the savings on your energy costs annually if you replace a 1994-made dishwasher with a current model.

Do the dishes during off-peak hours

If possible, delay doing the dishes until off-peak hours when electricity rates are lowest. Shaving a few centavos per kWh may not seem like much, but the amount adds up. So the more energy you save, the more money you get from the reduction on your utility bills.  

FAQs

Conclusion

Now that you have the answer to the question of how much electricity does a dishwasher use, you can better adapt your habits to meet your goals. It’s not only a matter of how many watts your appliance consumes. You also need to consider how efficient it is in using water. Modern dishwashers typically use less electricity, so if you have an older model, switching to a decent energy-efficient dishwasher can positively affect your electricity bill. 

Updated on 10-25-22