How Much Water Does a Dishwasher Use?

How much electricity does a dishwasher use?

The average dishwasher uses between 200 to 800 kWh per year of electricity, with older dishwashers tending toward the top of that range. To truly maximize the efficiency of your dishwasher, look for ENERGY STAR certified models, which meet the strict EPA and DOE energy efficiency criteria. These dishwashers must use less than 270 kWh per year and allow you to save more than 5,800 gallons of water over their lifetimes.

Most of us use warm water for washing and rinsing our dishes, which means half the water used for a load of dishes needs to be heated. Heating two gallons of water with a hot water heater takes just under 1,000 BTUs. Just like with your bathtub or kitchen sink, the warm-to-hot water in your dishwasher has to be actively pre-heated before it makes it inside the appliance itself.

Tip: If you’re looking to find out how much water your personal dishwasher uses, check for its product description online. These will usually include statistics about the dishwasher’s water consumption. The user manual or energy guide label are other good places to look for this information.

What factors influence dishwasher water usage?

There are many factors that influence how much water a dishwasher uses per load, including the specifics of your machine. Pay attention to:

• Dishwasher Model: As mentioned above, certain, ENERGY STAR certified appliances will use less water per cycle than those withoutthat haven’t achieved the rating. Something else to pay attention to is the age of your appliance. Older dishwashers, like those from the 1990s and prior, used up to 15 gallons of water per load.
• Cycle Type: The cycle you select for dishwashing can also have a big impact. Heavy or pots and pans cycles will use more water to tackle tough grime, while eco or light cycles tend to be more energy-efficient through reduced water usage and lower temperature cycles. Knowing when to use which cycle can help to really streamline your overall dishwasher water consumption.
• Load Size and Placement: How you load the machine also plays a crucial role in dishwasher water usage. Overloading the dishwasher can prevent water from reaching all the dishes, leading to inefficient cleaning and potentially requiring a second wash. On the other hand, running a half-empty dishwasher wastes water unnecessarily. The key is to properly space the dishes and fill the machine to its recommended capacity to make your cycle as energy-efficient and effectively cleaning as possible. 
• Maintenance: A well-maintained dishwasher operates more effectively, using the right amount of water for each cycle. Cleaning the filter, inspecting and clearing the spray arms, and making sure there are no leaks can all contribute to better water conservation. Plus, keeping your dishwasher in top shape means it will last longer, saving you money in the long run.

Is water usage higher for the dishwasher vs. hand-washing?

It may seem reasonable to hand-wash when you have only a small number of dishes to do, but it’s actually extremely wasteful. Obviously you wouldn’t wash an entire load by hand with an empty dishwasher at your disposal, but if you did, you could use more than seven times the amount of water your dishwasher requires. Using an ENERGY STAR certified dishwasher instead, for example, ends up saving $3,200 in energy and water compared to hand-washing over the lifetime of the appliance.

Contrary to what your mother told you, rinsing each plate before tossing it in the dishwasher really doesn't do much good. The dishwasher simply doesn’t require that sort of preparation, and the water you use to do so is just being wasted. Simply scrape your scraps in the trash and call it good.

How to get the most out of your dishwasher

1. Run Only Full Loads: To make the most of your dishwasher’s water and energy usage, wait until it’s fully loaded before running a cycle. A full dishwasher uses the same amount of water as a half-full one, so loading it to capacity is your best bet.
2. Use the Eco or Energy-Saving Cycle: Whenever possible, opt for the eco or energy-saving cycle on your dishwasher. These settings are designed to use less water and lower temperatures, and can make a big difference in minimizing your dishwasher’s water usage.
3. Avoid Pre-Rinsing – Just Scrape: Save water by skipping the pre-rinse. Modern dishwashers are designed to handle food residue effectively, so simply scrape off excess food before loading your dishes. Let your dishwasher do the heavy lifting.
4. Regular Cleaning and Maintenance: Keep your dishwasher in top shape by giving it some routine care— and don’t be afraid to call in a Pro if something feels really wrong!
5. Load Dishes Correctly: Properly spacing your dishes makes sure that water can reach all surfaces. Avoid overcrowding, and make sure larger items like pots and pans don’t block the spray arms. 
6. Choose the Right Detergent: Using a high-quality detergent can play a big role on your journey towards improving dishwasher water consumption. Some detergents are formulated to work better with eco cycles and lower temperatures so that your dishes get clean without the need for extra rinsing or rewashing.

Dubious dishwasher efficiency? Don’t worry, be warranty.

As essential as it is to your day-to-day life, your dishwasher is a part of your home you should feel confident about. With robust home warranty coverage from American Home Shield for your home’s system and appliances, including your dishwasher,  from American Home Shield®, you can rest easy knowing that repair help is just a service request away.

AHS assumes no responsibility, and specifically disclaims all liability, for your use of any and all information contained herein.