There is a long running debate about the most energy efficient way to wash your dishes. Is it using the dishwasher, or washing by hand? This debate has been ongoing for as long as dishwashers have been on the market. Arguments range from time saved to water consumption, from costs to the impact these options have on the environment. But which option is truly the best?

A dishwasher is more water-efficient than hand washing dishes in the sink

When it comes to energy efficiency, hand washing dishes may seem like the ideal option for cleaning up after every meal. And judging only by what our eyes can see – the size of the kitchen sink versus the size of the dishwasher's interior - it's easy to come to that conclusion. But looks can be deceiving.

Hand washing the equivalent of a dishwasher full of dishes uses significantly more water than a dishwasher. Hand washing uses even more water if you are in the habit of filling one sink with hot water for washing and another for rinsing, or letting the tap run to rinse.

Using a dishwasher is more energy efficient than hand washing dishes because it uses less hot water.

Filling the average kitchen sink can take between 15 and 20 litres of water. While a running tap uses approximately six litres of water per minute (depending on many factors, including water pressure and the age of the pipes).

Newer model dishwashers, especially those with an ENERGY STAR certification, can use as little as 15 litres of water per load.

Even with a smaller number of dishes being washed multiple times daily, hot water consumption is likely higher than it would be if you were running the dishwasher once daily. In addition to that, other steps can be taken to make dishwasher usage even more efficient.

How to use your dishwasher more efficiently

  • There is no need to pre-rinse dishes before placing them in the dishwasher.  Simply scrape off food scraps and grease without rinsing. This will avoid extra water use.
  • You can also skip the heated drying cycle. Many new dishwashers have an air-dry option which is more energy efficient. A rinsing aid will help dishes dry more quickly. You can also open the dishwasher door a crack at the end of each cycle to help dry the dishes.
  • Avoid the urge to run the dishwasher when there isn't a full load.
  • Position dishes according to the dishwasher manual's instructions for optimum cleaning.

How to save energy when washing dishes by hand

Some items, like cast iron pans and your grandmother's good dishes, should not be put in the dishwasher. And not every home has a dishwasher. If you need to wash items by hand, here are tips for completing the task using less hot water.

  1. Take extra care scraping your dishes and pans before placing them in the sink. That will help your soapy water be usable for more dishes.
  2. No need to fill the sink all the way. In many cases a half-filled sink will do the job.
  3. Rinsing your dishes with cool water is just fine, especially if you plan to let your dishes drip dry.

It all comes down to hot water use. A dishwasher uses much less hot water than washing the same amount of dishes by hand.

Determining the most energy efficient way to wash dishes all comes down to hot water use. In most cases, a dishwasher uses much less hot water than washing the same amount of dishes by hand. Household hot water consumption can account for up to 20% of your energy bill so taking steps to reduce the amount of hot water you use each day is good for your budget and the environment. Find more kitchen efficiency tips here.

FAQs

Is it better to use a dishwasher or hand wash?

For most people, using a dishwasher is more energy-efficient than hand washing dishes because it uses less hot water.

Is it cheaper to hand wash or use a dishwasher?

In most households, the dishwasher uses less hot water than hand washing and is, therefore, a cheaper alternative to washing dishes by hand.

How does a dishwasher differ from hand washing?

A dishwasher is designed to be energy efficient in its water usage and safety features for sanitizing while saving time by taking care of the dishes – a chore disliked by many. Hand washing dishes can use more hot water, especially if you also rinse the dishes with hot water.

How does using a dishwasher save on energy and water?

Modern dishwashers (especially ENERGY STAR® certified dishwashers) are energy-efficient by using less water which saves energy by having to heat less water.