A lot of people think that washing dishes by hand saves water and energy, when actually, it’s the other way around. A modern dishwasher uses approximately 15% of the water that would be used to wash the same dishes by hand.
Here are the results from a 2011 study overseen by experts from Bonn University and conducted to measure differences in water, energy, time taken and cleaning results of washing dishes by hand vs. using a dishwasher.
In the study, a US dishwasher was loaded to capacity with 12 place settings, soiled according to EN 50242* test method, while 81 participants each washed up the same volume of soiled dishes by hand.
What these consumers think of using a Dishwashing vs. Handwashing:
- 69% of participants who own a dishwasher identified the timesaving aspect as their main reason for purchase.
- 45% responded that they regularly have so many dirty dishes at home that the use of a dishwasher is necessary.
- Resource savings were found not to be top of mind when purchasing a dishwasher with less than one-third of dishwasher owners doing so in order to save water and energy.
The reality of dishwashing by hand:
- Water used - 140 L
- Energy used - 3.5 kWh
- Time spent - 71 min
The reality of dishwashing in a dishwasher (at 3 levels):
- Water used – Quick: 13 L /Normal: 18 L /Intensive: 27 L
- Energy used – Quick: 0.9 kWh / Normal: 1.6 kWh / Intensive: 2.0 kWh /
- Time spent loading and loading: 9 minutes total
So not only does the dishwasher save you time by doing all of the work for you, but dishwashing actually does it with less water and energy. Even more of an excuse to never wash another dish by hand again!
Download full results here.
* European test standard used for energy label testing of household dishwashers.