Dishwasher FAQs
What’s the big deal about energy efficient dishwashers?
More than half of American households have a dishwasher. The 65 million residential dishwashers in the United States use 24,000 GWh of energy use per year. Dishwashers manufactured today clean better and are more efficient than older models, but finding the most energy efficient dishwasher for your home can be challenging.
To help you make the best choice for your family and the earth, TopTen took an in-depth look at the market for dishwashers. The most relevant information is located here, including our criteria for selecting the ten most efficient products.
Where do we get our info?
Energy Star, the Federal Trade Commission, California Energy Commission, the American Water Works Association, the Consortium for Energy Efficiency (CEE), the Environmental Protection Agency, the Department of Energy, and various professional and manufacturing trade publications provided valuable information about the dishwashers listed at TopTen. For a complete bibliography, read How We Evaluate. Resources are listed at the end of that page.
How do we decide what dishwashers to include?
There are 576 dishwasher models from 32 manufacturers sold in the US today. Of these, 539 dishwashers, with varying levels of water efficiency, are active in the ENERGY STAR database. Since water use corresponds to energy use, TopTen placed a limit on acceptable water consumption among the Energy Star models. We chose the most energy-efficient dishwashers from our water-efficient list.
We also chose to evaluate only standard-sized dishwashers. If a compact model better suits your needs, you’ll find 23 compact dishwashers listed in the Energy Star database.
See How We Evaluate for data
How do we calculate cost savings?
To calculate dishwasher energy use, analysts add:
- Water heating energy, which accounts for 60% of the energy used by most dishwashers
- Machine energy (including water pumping, food disposal, and booster heating), and
- Drying energy
Why do some products have more than one manufacturer or model name?
The major manufacturers of TopTen dishwashers are Akso, Bosch, and Thermador. The difference between a model name/number is often based on cosmetic differences that do not affect performance or energy efficiency.
Do I have to go to a specialty store to find dishwashers listed on TopTen?
TopTen dishwashers are available at big-box home goods stores such as Lowe’s, along with local and regional independent stores. Products are also available online.
Will I pay premium prices for energy dishwashers?
Retail prices for dishwashers on the TopTen list range from $849- $2099
Is it more energy efficient to wash my dishes by hand?
Actually, according to studies in the US and Europe, modern dishwashers use substantially less water and energy than hand-washing.
What makes a dishwasher energy efficient?
Energy efficient dishwashers incorporate numerous energy-saving technologies and features. These include more efficient water jets, improved filters and dish rack designs, “no-heat” dry cycles, low standby power and, in some models, adaptive soil-sensors.
- Water Jets
- The energy used to heat water accounts for approximately 60% of dishwasher energy use, so it’s a good thing that average dishwasher water consumption has dropped from 15 gallons per cycle for 1980s models to around 4 gallons per cycle for 2009 ENERGY STAR-qualified units.
- Water jets that precisely and efficiently target the water spray save energy because they use less water, and therefore have less water to heat.
- Improved filters stay clearer longer, allowing for better flow of air and water throughout the dishwasher.
- Efficient dish-rack designs save energy by allowing users to put more dishes into each load than other machines.
- Drying cycles that circulate unheated air over the dishes use less energy than cycles that heat the air before circulating it.
- Adaptive Soil Sensors save energy by adjusting the cycle time and water use to match the size and soil-level of the dish load.
