Would it surprise you to learn that a dishwasher uses much less water than washing up by hand?
In a 2009 Australian hand dishwashing study, Colmar Brunton found that washing a full dishwasher-load of dishes by hand uses about 75 litres of water, compared to the 14 litres used by the average machine. Dishwashers are so efficient because they clean and recycle the water they use.
During the wash
If you wash your dishes by hand with running water, 6 litres of water disappear down the drain every minute. This means that in only two minutes you lose 12 litres – the total amount of water a dishwasher uses during a normal cycle.
After the wash
On to rinsing by hand, and your clean hot water’s running down the plughole at a rate of knots. Once you’ve turned the tap off, the hot water drawn from the tank cools in the pipes, wasting the energy used to heat it. The average dishwasher, on the other hand, draws and heats only the water it needs, using just 3–4 litres in the final hot rinse.