Some consumers still choose not to have a dishwasher in their household because they believe that washing dishes by hand makes more ecological sense. While washing dishes by hand doesn’t require electricity, the water consumption can be not insignificant, depending on how often and how you wash your dishes. In addition, the water and electricity consumption of dishwashers has developed positively in recent years. We therefore want to investigate here the question of how much electricity and water a dishwasher consumes and what costs are incurred as a result compared to washing dishes by hand.
How much electricity does a dishwasher consume?
Unlike hand washing, a dishwasher requires electricity to function. On the EU label, which must be attached to every new appliance, the power consumption is given in kilowatt hours (kWh). The electricity consumption listed there is an estimate based on 100 standard wash cycles. Of course, depending on how often and how you use your dishwasher, electricity consumption may vary and actual consumption may differ greatly from the stated consumption. We have explained how you can best save energy with your dishwasher in the linked article.
On the EU label, you also have the opportunity to see at first glance how energy efficient a device actually is. The machine’s energy efficiency class is highlighted in particularly large letters. Dishwashers with energy efficiency class A are the best appliances since March 2021. The following table is intended to show what a standard dishwasher with a width of 60 cm and a rated capacity of 12-14 place settings consumes in terms of electricity and what costs are incurred as a result.
Electricity consumption of a dishwasher (old status – update to follow shortly)
|Energy efficiency class||Power consumption / year (approx. 280 rinses)||Cost / year|
|A+++||approx. 237 kWh||82,03 £|
|A++||approx. 262 kWh||90,68 £|
|A+||approx. 292 kWh||101,07 £|
Narrow dishwashers with less nominal capacity of 8-10 place settings consume between approx. 215-230 kWh / year.
How much water does a dishwasher use?
What many of the above “hand washers” probably don’t know is that the water consumption of even a 10-year-old dishwasher is lower than when washing dishes by hand. For example, washing dishes by hand uses an average of 46 liters of water. The dishwasher uses only about 15 liters of water for the same amount of dishes.
Nevertheless, today’s dishwashers naturally also differ in their water consumption. Particularly economical models even consume less than 10 liters per wash cycle, but most are in the range of 10 to 13 liters. Here again, we want to use a table to show what a standard dishwasher with 12-14 place settings consumes in water for approx. 280 annual wash cycles. The energy efficiency class is irrelevant here.
Water consumption of a dishwasher
|Model||Water consumption / year (approx. 280 rinses)||Cost / year|
|Model with low water consumption||approx. 2.660 l||12,64 £|
|Model with high water consumption||approx. 3.360 l||15,97 £|
Again, it’s worth noting that small machines, like a tabletop dishwasher, use even less water.
How much electricity and water is consumed compared to hand washing?
A comparison to washing dishes by hand is of course always somewhat difficult, since it depends on how often and how much dishes are washed by hand, which of course also varies the consumption of water. Nevertheless, experts agree that washing dishes with a machine is significantly more environmentally friendly overall than doing the job by hand. This has been proven in numerous tests with both newer and older dishwashers.
Particularly in terms of water consumption, the dishwasher performs significantly better in ecological terms. Only in the use of detergent is there still room for improvement, as the machine requires somewhat more chemicals.
|Comparison at 280 rinses||Dishwasher with good energy efficiency||Washing by hand|
|Power consumption||237 kWh|
|Water consumption||2.660 l||12.880 l|
|Electricity costs at 29,13 Cent/kWh||82,03 £||0 £|
|Water costs at 0,4 Cent/l||12,64 £||61,22 £|
|Total costs||94,67 £||61,22 £|
You should use the Eco wash cycle as often as possible for lightly soiled dishes. It lowers the wash temperature by 5 °C, which results in an energy saving of approx. 10 %.