Same old myth - now with debunkable numbers

[katakanadian]

I've always been suspicious of the claim that it is better to use a dishwasher than to do dishes by hand. Umbra Fisk's latest item repeats that claim and she gets a round of flack from several commenters including me (#7

Comments

[cybertoothtiger]

It's like so many 'green' things: it depends on the user and the other technology in the home. My dishwasher uses 6.7 litres of water to wash all the dishes for a day for four people, and I don't use the dry cycle. I just turn it off and the residual heat dries them

[katakanadian]

I like that you have thought it through as it pertains to your situation. I'm impressed that your dishwasher uses only 6.7L of water because the only numbers I have heard are 30L+.

Every time I have heard/read someone giving advice on hand vs machine dishwashing they have never talked about what kind of handwashing technique is so wasteful in order to help people judge for themselves. They just always say 'you'll be surprised to learn that machine washing uses less water than hand washing'. The implication seems to be that everyone should get a dishwasher.

Something that most people don't consider is the environmental cost of producing that machine. All the water and energy consumed and pollution produced during the mining, refining, manufacture, advertising, and shipment of said machine. It's still possible for the dishwasher to be more efficient/effective but the difference is much smaller than when you just compare daily usage.

[cybertoothtiger]

True, true. The dreaded Life Cycle Costs will bite you every time. We have a terribly inefficent old fridge at the cabin (we won't even discuss the environmental impact of having a cabin. It's um, really old and has no running water?) but as we only use it a few weekends a year, the life cycle cost of replacing it would not really save anybody anything.

And the rain barrels I have in town were placed too close to the house and they overflowed in a major rainstorm and caused flooding and mold in my basement. I saved a little water but I used heaps of drywall and flooring instead. So my rainbarrels had a huge life cycle cost. *Sigh*

I work in Environmental Ed, so I try to do the stuff I'm asking other people to do, and it's interesting how it's not always as simple as all those green guides would have you believe.

I'm rambling. Sorry!

[katakanadian]

Ramble away!

It does require an awful lot of very broad thinking to assess what is really a better way to do things. There are so many caveats that it's easy to become discouraged or to start thinking we really have to go back to ultra lo-tech living. As I said to some friends earlier today, I'm about 80-90% sure that the human race has fucked itself because no one is willing to do what needs to be done (reduce population, give up cars, relocalize economies, restrict air travel, pay a fair price for everything, stop making crap trinkets, eat much less meat and fish, etc). I still have hope that there is 10-20% chance we will slow down climate chaos enough to maintain civilization.

[ionracas]

I am American but have lived in the UK/Ireland for years....in the States, if you're handwashing you run the water the whole time, and then rinse as you go. In the UK/Ireland, in my experience, you fill the sink and wash and put the dishes in the drainer or dry with a tea towel, without rinsing. The only water you've used is the sinkful. In my house, we boil one kettle of water to do the dishes, we don't even have a hot water heater.

When I mention this, the response is usually 'omg gross there will be dish soap on the dishes!!!'. But there isn't, not anymore than if you rinsed. And it's non toxic anyway, particularly if you use a natural brand. And if you use a dishwasher, you use rinse aid which is designed to stay on the dishes. And if you really can't get your head around it, run the kettle again and pour it over the dishes in the drainer. But washing dishes by hand is most definitely the greenest way to do it--you've just got to do it the green way. And it's easy.

[katakanadian]

Why boil water for rinsing? That's a big waste of energy. Any soap residue will rinse off quite well with cold water.

One of the most galling examples of energy and water waste I ever saw regarding dish washing was when a friend of mine washed out a 2L pitcher and then proceeded to fill it to the brim with hot water, dump it out, fill it to the brim again with hot water and dump it out again. This guy also habitually left ~100mL in his water bottles when throwing them into the burnable trash. >_<

[pebblerocker]

Perhaps some dishwashers are better than others, but in my experience you have to handwash the dishes anyway because they always come out of the dishwasher with food stuck to them.