A friend of mine told me that it is cheaper and more energy efficient to use a dishwasher than to wash dishes by hand.
She also said that to be as energy efficient as possible, you shouldn’t even rinse the plates before loading the dishwasher, just scrape the food into the bin.
Is it really true that using a dishwasher is cheaper than washing dishes by hand – and wouldn’t neglecting to rinse the dishes lead to dishwasher clogging? veg e-mail
Dishwasher or sink? Experts agree that using the dishwasher is more efficient than doing the dishes by hand
Helen Kirrane from This is Money answers: Due to the crisis in the cost of living, many households are ditching the kitchen sink to lower their bills.
Everyone has an opinion on whether it’s cheaper to hand wash in the sink or use a dishwasher, so we’re putting this to the experts to find out once and for all.
Which is cheaper: sink or dishwasher?
There are two big things to consider when working out which is cheaper: the cost of water and the cost of heating that water.
Contrary to popular belief, dishwashers use less water than sink rinses.
The average dishwasher uses 10 liters of water at a time – while a regular sink would only fill up once with nine liters of water.
One dishwasher can hold two to three bowls of crockery and cutlery, which means that 10 liters of water in a dishwasher will wash as many items as 27 liters in a sink.
The total dishwashing cost depends not only on the amount of water used, but also on the cost of heating it.
But the dishwasher also beats the sink in terms of energy consumption.
Ben Gallizzi, energy expert at comparison site Uswitch, says: ‘It may seem surprising, but modern dishwashers are more efficient than hand washing for both water and energy use when washing a full load.
‘Filling a nine-litre sink with hot water can cost just under 16p to heat up – but you’re unlikely to be able to wash a dishwasher’s dirty dishes in the same water, making the appliance a better overall cleaner. option’.
‘While one wash in a dishwasher costs about 26 pence in energy, and generally does all the washing up used by the average household in a day.’
In other words, washing dishes by hand costs between 32p and 48p per day (for two or three sinks), while using a dishwasher costs 26p for one load.
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However, there are many variables, such as the size of your dishwasher and sink, and the cost of detergent, dishwasher tablets, rinse aid and dishwasher salt.
If you wash up by hand, the charity Energy Saving Trust recommends always using a bowl instead of a constantly running tap.
You might also consider installing an aerator on your existing kitchen faucet to reduce the amount of water that comes out without affecting how it washes or rinses.
An aerator is a small gadget with small holes that works by attaching to the spout of faucets and adding air to the water stream.
These use less water and can save you £30 a year on your energy bill, according to the Energy Saving Trust.
Tap off: pre-rinsing dishes before placing them in the dishwasher should be kept to a minimum as this can lead to high bills
Need to rinse your dishes?
Pre-rinsing heavy food-covered dishes can help prevent food waste from clogging your dishwasher’s filter, but remember that running the hot tap will cost you money.
“Try scraping off the leftovers or give them a quick rinse with cold water if necessary,” says Gallizzi.
‘Research suggests that a running hot tap can use 100 liters in just ten minutes, while most dishwashers use less than 10 liters per cycle, so keep pre-rinse to a minimum.’
How to keep your dishwasher running efficiently
According to the Energy Saving Trust, reducing the use of your dishwasher by one cycle per week can save you £17 per year on your energy bill.
Running your dishwasher when it’s half empty is a waste of energy, so wait until you have a full load before using it.
Filling your dishwasher to a full load will use less water than if you filled the sink, according to A-Plan Insurance.
There are even more ways to save energy costs when purchasing a dishwasher or other new appliance.
Alex Hasty, director of comparison website ComparetheMarket, suggests choosing a model with the highest energy rating.
A is the most energy efficient, G the least.
Also keep in mind that your dishwasher may have an eco option, which should help keep energy consumption lower overall.
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