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I've read that a dishwasher is less wasteful than hand-washing of dishes (perhaps this isn't true for people who are very, very scrupulous about their use of water while washing dishes, but that's not most of us).



Yeah, modern dishwashers use less water per washing cycle than it takes to fill the kitchen basin for handwashing.


Fill the basin? You don't just scrub each dish with a damp sponge spotted with dish soap then rinse it?


To be honest, I used to wash dishes under running warm water, probably quite wasteful.

By the way, around here (North Europe) we have special dishwashing brushes that apparently aren’t a big thing in most parts of the world.


Any examples of the special dishwashing brushes? I'm curious.


These sort of things, with a handle and nylon bristles: https://www.amazon.com/OXO-Good-Grips-Dish-Brush/dp/B00004OC...


Oh, that's what I use (I'm in California). They're pretty common here as well. I don't understand people who use sponges. They're mold applicators as far as I'm concerned :)


I like to use a brush to get off all the gunk and then do detail work with a sponge.


A lot of people do it that way. Anyway I rinse the dishes but I'm not sure I'm using less water that way.


Depends on the dishwasher setting used and number of place settings being washed of course. [0]

[0] PDF https://web.archive.org/web/20091109165849/http://efficient-...


Assuming you use the dishwasher correctly: you don't overload it, You don't run it too empty, and you don't pre-wash/rinse your dishes. Fail either of the above and a dishwaser uses more water.

When you overload the dishwasher things don't get clean and then you wash by hand afterwards (in the case of pots/pans this might still be less water use just because when hand washing you are likely to drain the filthy water half way through)

I've seen people who scrub the food off by hand under running water before putting it in the dish washer - they are clearly using more water since hand washing plus rinsing the soap off is using less water than they use for the rood rinse.

That said, I would not expect a dishwasher can actually wash the inside of your straws so that is one of the things that should be reserved for hand washing. If you use a minimal amount of water in your wash sink, and a minimal amount of rinse water hand washing can be a low water use thing. Most people leave the water running for longer than they need to for rinsing and this wastes a lot of water.


Arguments about water "consumption" (hint: it's still water afterwards - it tends to clean itself if you didn't outright poison it and wait a bit) do not apply in humid regions - saving water someplace else doesn't help regions with water scarcity one bit. Berlin is an extreme example, they need to pump water out of the ground in any case to prevent the area from reverting to a bog.

Hot water usually costs a lot of valuable energy though.


The world is going to have more, not fewer, dry regions where water must be conserved over time.


I put straws in the basket with silverware. Works fine unless you've let something really dry on there (like a smoothie).


water is not the problem. Electricity is.

and besides, not everything go in the dish washer. And moreover some the dish washer soap can attack the surface of many things => increasing the need to replace those things...


I think people in California, Cape Town, or various similar locales might disagree with the idea that conserving water is unimportant. How much electricity does a dishwasher really use, anyway?


About 1-2 kWh and 4-6 gallons of water per use.


you're right, while trying to open the eyes of the older poster, I actually closed mine :-( oops


Absolutely. A dishwasher in the average American household, unless they're having massive dinner parties every night, is wanton arrogance. They not only use more resources than handwashing, it also takes longer.


I am happy to report that you are completely wrong about this.

The water usage is almost a 10x difference and the power usage of handwashing is 2/3 more:

"A European study comparing hand washing to machine dish washing found that hand washers used as much as 27 gallons of water and 2.5 kilowatt-hours (kWh) of energy to wash 12 place settings, compared with the 4 gallons and 1.5 kWh used by a hyperefficient dishwasher to wash the same number of dishes."

https://www.rodalesorganiclife.com/wellbeing/washing-dishes-...


27 gallons is over 120 L that's over a tenth of a ton of water I don't believe that figure


Wait until you figure out how much even a low flow shower uses.


Yes I could I have a Btech in thermo fluids :-) but this is doing the dishes by hand after a large meal no way do you use that much.


It must surely include rinsing under a fast-flowing tap (something I rarely bother with personally), and/or maybe doing the washing under a running tap too. I don't see how you could get to 120L otherwise.

120L = 7 very full sinkfuls of my fairly standard size kitchen sink. 7! For 12 people's-worth of stuff!


It sounds like he was describing just measuring how much a typical person washing dishes uses. I'm sure if you were specifically concerned with conserving water you could do better.


I noticed that the photo at the top of the article shows somebody washing under a running tap, so maybe that's how they got to 120L.

I'm not myself concerned all that much about conserving water, but I am a normal person, so I don't wash my dishes under running water. I fill the sink up with water, stick in some washing-up liquid as it fills, then once it's mostly full (12-15L of water?) I use that. Total use per wash is then 12-15L. Maybe a bit more if I give something a rinse. (Very much optional in my view for most items - but some things do need it.)

You can wash a lot of stuff in that much water! So that's why I am a bit surprised at people using 120L to wash twelve places'-worth. That's eight times the amount I'd use for washing 3-4 people's-worth of stuff and all the items used to prepare the food in the first place.

Poor scalability!

(I think my dishwasher uses 17L per wash so I don't worry too much about using that instead. I am quite lazy.)


Plug the sink next time you're washing dishes.


Why do you think I don't? And use a washing up bowl


I never do except by accident and it illustrates to me that I'm using a ton of water when I hand-wash dishes.


You seem to misunderstand. Dishwashers use less heat and water than hand washing, not more.




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