You’ll be pleased to learn that studies have shown that a dishwasher is indeed more energy-efficient than washing dishes by hand. However, it’s a grey area, as it depends on how you hand-wash your dishes.
For example, some people use the tap to pre or post-rinse dishes. Some leave the tap running non-stop and others opt to fill the sink and leave the rinsing. Then there’s washing-up bowls. Some fill the bowl right to the top, whereas others use a lot less water.
On average, the majority of modern dishwashers use 11-13 litres of water per cycle. Hand-washing, on the other hand, can call for up to nine times that amount.
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Is it cheaper to use a dishwasher?
This, again, depends on your dish washing habits. As long as you only run your dishwasher once it’s fully loaded, it should cost you less than hand-washing.
Research has shown that a single dishwasher cycle costs the same in energy and water as turning the hot water tap on for six to nine minutes, or filling up four to six washing-up bowls (depending on whether the household has a metered or unmetered water supply).