Are you thinking about purchasing a dishwasher?
Or simply wondering how well a dishwasher performs vs. handwashing?
Twenty percent of American homes with dishwashers don’t even use them. The press claims that’s bad for the environment, but is it?
We often hear about a dishwasher’s energy efficiency and reduced water use. Seldom is there a peep about a dishwasher’s limited lifespan or a question about the validity of studies “proving” the superiority of a dishwasher to handwashing
We don’t sell dishwashers at Orange Coast Plumbing, nor do we repair them. But we do care about water, energy, and the environment.
So we’ll give you the good, bad, and ugly about dishwashers. And we’ll make an objective case for purchasing one — or sticking to hand washing your dishes.
Claim #1: Dishwashers Use Less Water Than Handwashing
Reality
Maybe. A dishwasher needs 4 gallons of water for a standard wash cycle. Water flows from a wide-open tap at about 2.2 gallons per minute.
If you can complete your hand wash quickly without leaving the tap wide open, you may save water compared to a dishwasher.
And if your dishwasher is set to extra cycles, like pre-wash and extra rinse, all bets are off.
Also, do you pre-wash your dishes by hand before placing them in the dishwasher? You’d have to account for this water use as well.
Claim #2: Dishwashers Use Less Energy
Reality
Maybe. This claim ties to the water heater above all else. If it’s far from the sink, you’ll waste energy (and water) waiting for the hot water to arrive and again when you leave unused hot water in the pipes to cool. All that energy to heat water left in the lines goes for naught.
But if your home has a tankless water heater, it will be close to the kitchen sink. Hot water arrives almost instantly. And a tankless heater burns up to 34% less energy than a storage-tank water heater.
So, the jury’s out regarding a dishwasher’s most frequently cited environmental benefits. For more information on the ecological impact of washing dishes, please read this excellent article from Tree Hugger.
Claim #3: Dishwashers Do a Better Job of Cleaning Dishes
Reality
It depends. Temperatures inside a dishwasher reach temperatures of 130-140° F. For safety reasons, the temperature in a water heater should go no higher than 120° F.
So the dishwasher wins — except it takes a temperature of 149° F or more to kill most waterborne bacteria. Dishes frequently come out of the dishwasher dirty, with encrusted food and clinging particles, and must be rewashed by hand.
Claim #4: A Dishwasher Saves Money
Reality
Maybe. If it saves significant water and energy, a dishwasher may save you money over its life.
- But a dishwasher costs anywhere from a few hundred dollars to over $1,000, plus installation.
- Dishwashers last only 7–10 years, on average.
- Dishwashers tend to develop maintenance issues after 5 years. The average dishwasher repair in America runs over $200.
So, the jury’s out on this claim as well. It’s linked directly to claims #1 and 2.
Other Benefits of Dishwasher (Pros)
- Convenience: No doubt it’s convenient to have a machine do the bulk of the work for you.
- Time savings: Again, no argument. Loading dishes in the dishwasher takes much less time than washing them by hand.
- Sterilization: Dishwashers get hotter than tap water temperatures. Bacteria are eliminated more effectively, but not completely.
Drawbacks of a Dishwasher (Cons)
- Price of the unit and installation costs: As mentioned, dishwashers cost several hundred dollars (or more). You’ll need to factor in installation costs as well.
- Noise levels: The sound of a dishwasher running is usually noticeable, especially in a small home.
- Wear and tear on dishes: Cleaning occurs via a powerful spray cycle, so delicate items may not survive multiple washes or the hot, dry cycles that follow.
- Environmental impact of detergents: Many dishwasher detergents include phosphates, which can harm the environment. Always opt for phosphate-free detergents.
- Maintenance: Hard water creates lime deposits that clog a dishwasher. Unless you stay vigilant and descale your dishwasher often, you could face a $200+ repair.
- Limited appliance life: A dishwasher may last 7–10 years. The more you use it, the faster it will wear out.
- Limited cleaning ability: The most challenging dishes still require pre-washing, scrubbing, and manual rinsing.
Conclusion
While a dishwasher can be a great convenience and potential water and energy saver, it may not always be the most economical or ecological choice. Much depends on your habits, preferences, and water heater.
Ultimately, if handwashing fits well into your lifestyle and you’re conservative with your water use, there’s no need to rush to the appliance store as your green initiative for the year.
FAQs: Dishwasher Vs. Handwashing
Q: Can using a dishwasher really save water compared to handwashing?
It depends on your washing habits. A dishwasher typically uses around 4 gallons of water per standard cycle. If you handwash dishes with care — such as by filling a basin rather than running the tap — you might save more water than a dishwasher. However, prolonged water use while handwashing can quickly surpass the dishwasher’s efficiency.
Q: Does a dishwasher use less energy than handwashing?
Not always. A dishwasher’s energy consumption depends on how it’s used and the type of water heater in your home. Energy can be wasted if your water heater is far from the dishwasher. However, a tankless water heater or a high-efficiency dishwasher can minimize energy use.
Q: Is using a dishwasher more hygienic than handwashing?
Dishwashers tend to reach higher temperatures (130-140°F) than typical tap water during handwashing, which may kill some bacteria more effectively. However, to truly sanitize dishes, water temperatures need to exceed 149°F, which most dishwashers can’t achieve. Food residue left behind may also require hand scrubbing after a dishwasher cycle.
Q: Are dishwashers environmentally friendly?
Dishwashers can be eco-friendly when used efficiently. High-efficiency models consume less water and energy than older units. However, their environmental impact also includes manufacturing, distribution, and eventual disposal. Also, the detergents may have harmful chemicals, so consider eco-friendly options.
Q: How long does the average dishwasher last?
With proper care, the average dishwasher has a lifespan of 7–10 years. However, frequent use and hard water conditions can shorten its life. Regular maintenance, such as descaling and cleaning the filter, can extend its longevity.
Q: Do dishwashers damage dishes over time?
They can. The high-pressure water jets and high heat during drying cycles can cause wear and tear on delicate items. To prevent damage, it’s best to handwash fragile dishes.
Q: Is it necessary to pre-rinse dishes before loading them in the dishwasher?
Generally, it’s not necessary to pre-rinse dishes before loading them into modern dishwashers. Most models are designed to handle food residues. However, scraping off large food particles is recommended to prevent clogs in the dishwasher’s filter.
Q: How often should I maintain my dishwasher?
For optimal performance, you should clean your dishwasher filter monthly to remove food debris. In areas with hard water, descale the dishwasher every 3–6 months to prevent lime buildup. These maintenance steps can keep your dishwasher running efficiently.
