Challenging Assumptions
A bit in this month's Wired took me by surprise: Washing dishes by hand may be more energy and resource intensive than using a dishwasher.
Of course, like many little studies like this one, the parameters expand to infinity and beyond, requiring one to specify several different and perhaps wildly varying factors to reach a limited conclusion set.
From the article (couldn't find it online)
Hand washing (water running): 5,974 gls, 1,243 kw/hrs (all numbers annual)
Hand washing (2 basin sink): 1,419 gls, 295 kw/hrs
Standard dishwasher: 1,563 gls, 334 kw/hrs
High-efficiency dishwasher: 868 gls, 276 kw/hrs
Standard dishwasher (rinsing first): 3,473 gls, 735 kw/hrs
High-efficiency dishwasher (rinsing first): 2,778 gls, 677 kw/hrs
Of course, how much water is used in the "rinse?" Using which "standard" dishwasher? Which "high-efficiency?" At what flow rate did they assume the "water running?"
Still, this starts to make sense. Our old dishwasher had come with the house. It died. I didn't mind hand washing, so I just did it. Just a few months ago, though, the wife started the hinting. I'm not always home to do the chore, and one must admit, the pre-run dishwasher is a great place to hide the dirties.
I found a used and reconditioned roll-away at a little joint on Lake City Way for not too much (under $300). She was happy; therefore I was happy.
I did notice a few things that surprised me mildly at the time. After a hot water wash, the steam rises out of the machine the minute you crack the door. I was sure the auxillery heater was spinning our power meter, even though the HEAT DRY switch was off. My suspicions risen, I tried a cold wash. With the cold tap supplying all the water, though, the interior and the load felt icy cold.
Meaning all of that steam was a result of the hot water from the tap. That surprised and bemused me.
After reading this Infoporn, it clicked. Dishwashers, be they "high-efficiency" or not, insulate the hot water, meaning more of the heat in the water gets to the dishes and the gunk thereon. In a sink, by contrast, the heat is open to the elements and conducts through the sink itself, cooling quickly.
This becomes an issue when one realizes how many fats, oils and other lipids fill our diets and therefore our crockery. Even vegetarians face cleanup of natural lipids that melt well in hot water and gel to a streaky, coagulated mess in cold.
This observation fits well into the Home Effinomic mindset. I have met many that wash dishes by hand. I have met exactly that many levels of cleanliness in the dishes they have washed. Let's face it, folks: If you screw up the dishes, it can ruin the meal. One old college roommate of mine had sensitive hands, we all theorized, probably causing him to avoid using water sufficiently heated to execute a proper rinse. Ever taste unrinsed dish soap in your soup? By the way, that's his picture. Here he is, now a television reporter in Winnipeg, and a guy who can undoubtedly afford a dishwasher by now!
After reading this, I've decided to adjust my wash habits a bit. I still pre-rinse and scrape, but reuse the rinse from one dish to the next below, rather than treat each filthy plate and bowl with a fresh rinse. If I soak, I soak in a stack. The top plate displaces the water on the lower, meaning less water is used to cover the entire plate. My next task will be to measure the power and water usage from the dishwasher, and try to devise a way to measure my own handwashing consumption.
Then again, I'll just skip the handwash measurement. As Kelly proved in college, it will differ from everyone else's anyway.
Of course, like many little studies like this one, the parameters expand to infinity and beyond, requiring one to specify several different and perhaps wildly varying factors to reach a limited conclusion set.
From the article (couldn't find it online)
Of course, how much water is used in the "rinse?" Using which "standard" dishwasher? Which "high-efficiency?" At what flow rate did they assume the "water running?"
Still, this starts to make sense. Our old dishwasher had come with the house. It died. I didn't mind hand washing, so I just did it. Just a few months ago, though, the wife started the hinting. I'm not always home to do the chore, and one must admit, the pre-run dishwasher is a great place to hide the dirties.
I found a used and reconditioned roll-away at a little joint on Lake City Way for not too much (under $300). She was happy; therefore I was happy.
I did notice a few things that surprised me mildly at the time. After a hot water wash, the steam rises out of the machine the minute you crack the door. I was sure the auxillery heater was spinning our power meter, even though the HEAT DRY switch was off. My suspicions risen, I tried a cold wash. With the cold tap supplying all the water, though, the interior and the load felt icy cold.
Meaning all of that steam was a result of the hot water from the tap. That surprised and bemused me.
After reading this Infoporn, it clicked. Dishwashers, be they "high-efficiency" or not, insulate the hot water, meaning more of the heat in the water gets to the dishes and the gunk thereon. In a sink, by contrast, the heat is open to the elements and conducts through the sink itself, cooling quickly.
This becomes an issue when one realizes how many fats, oils and other lipids fill our diets and therefore our crockery. Even vegetarians face cleanup of natural lipids that melt well in hot water and gel to a streaky, coagulated mess in cold.
This observation fits well into the Home Effinomic mindset. I have met many that wash dishes by hand. I have met exactly that many levels of cleanliness in the dishes they have washed. Let's face it, folks: If you screw up the dishes, it can ruin the meal. One old college roommate of mine had sensitive hands, we all theorized, probably causing him to avoid using water sufficiently heated to execute a proper rinse. Ever taste unrinsed dish soap in your soup? By the way, that's his picture. Here he is, now a television reporter in Winnipeg, and a guy who can undoubtedly afford a dishwasher by now!
After reading this, I've decided to adjust my wash habits a bit. I still pre-rinse and scrape, but reuse the rinse from one dish to the next below, rather than treat each filthy plate and bowl with a fresh rinse. If I soak, I soak in a stack. The top plate displaces the water on the lower, meaning less water is used to cover the entire plate. My next task will be to measure the power and water usage from the dishwasher, and try to devise a way to measure my own handwashing consumption.
Then again, I'll just skip the handwash measurement. As Kelly proved in college, it will differ from everyone else's anyway.