Believe it or not, using a dishwasher is significantly more energy efficient than washing by hand. Who knew? I sure didn’t.
One study done in the European Union had 133 people wash 12 full table settings with the same amount and degree of food residue on each setting. The average water usage for hand washing was 103 litres of water and approximately 2.5 kilowatt hours of energy to heat the water. The energy star appliances used, on average, 15 litres of water and 1.5-2 kilowatt hours of energy. Also, half of the hand washers didn’t clean the dishes to the “acceptable level of cleanliness”.
But that doesn’t mean that you get off easy by using a dish washer. Being conscious of the number of dishes you use to reduce quantity as well as choosing the energy efficient setting and not using the heated drying option are a must. Especially if you use natural and or biodegradable dish soap or tabs; the heat seems to leave a film on your dishes if you combine natural dish detergent with heat. (post on household cleaners)
As an aside, don’t pour vinegar in your dishwasher in the rinse agent compartment. Most new dishwashers (read: energy efficient) have rubber valves that don’t respond well to vinegar. They will breakdown and plug up. Not ideal. If you want to use vinegar in your wash place a small bowl or container with a tablespoon of vinegar in it on the top rack. Voila! Sparkly dishes.
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