Conservation 101: the Compete to Conserve Blog

photo credit: chispita_666

Skeptical that your dishwasher is more energy and water efficient than washing by hand? To test this theory, Leah Ingram of The Lean Green Family suggests stopping up your sink as you hand-wash dishes and then measuring the water you’ve collected. It’s likely more than you think.

Ingram is right. In my test, I used 8.25 gallons on a day’s worth of dishes (breakfast, lunch, dinner) for a family of four. My methodology? I quickly rinsed our dishes, turned off the water, scrubbed, and then rinsed off the soap. I’m not sure I would have saved water even if I had filled the sink first, as the sink itself would have required a good scrubbing and rinse, too.

Considering the average standard dishwasher built since 1994 uses 9 gallons a load, and I can fit two day’s of dishes in one load, I can cut my water usage, not to mention my water-heating, by more than half. Good-bye dishwashing gloves!

They’ve Done Studies
I’m not the only one who found dishwashers come out on top. Researchers at the University of Bonn in Germany studied 113 people across seven countries and found that new, energy-efficient dishwashers use only half the energy, one-sixth of the water, and less soap than hand-washing. The study also notes that dishwashers get dishes cleaner, too.

More resources:
Energy Star Dishwashers

American Council for and Energy Efficient Economy

Waterwise a water-industry organization in the UK

Water Usage Calculator

photo credit: jsgphoto

I hate washing dishes. My husband hates washing dishes. And as soon as they are old enough, our two children will likely hate washing dishes too. Yet for years, I dutifully hand-washed our dishes, believing it to be more energy- and water-efficient.

Then I came across The Green Book: The Everyday Guide to Saving the Planet One Simple Step at a Time by Elizabeth Rogers and Thomas M. Kostigen, which suggested that new energy-efficient dishwashers beat hand-washing dishes, well, hands down.

For me, this was a revelatory moment, akin to when Woody Allen’s character in Sleeper awakens in the future only to learn that chocolate is good for you and exercise bad! Still, I was skeptical, so I researched the debate myself. Here’s how you can make the dishwasher come out ahead:

Old Dishwashers Bad, New Dishwashers Good
If your dishwasher is more than 10 years old, you might be better off hand-washing. But according to Energy Star’s downloadable guide (PDF), a new Energy Star-rated dishwasher, can save you an average of $40 in utility costs and 4,945 gallons of water a year over doing dishes by hand.

Run Only Full Loads
Your dishwasher uses the same amount of water and energy whether it’s full or not, so maximize your resources.

Scrape before You Load
We run our dishwasher every other day. To avoid crusted-on food that requires (ugh!) rewashing, we wipe them rather than rinsing, which wastes water.

Skip the Heated Dry Cycle
The dishwasher water is hot enough to evaporate quickly—about 15 minutes in our house—and you’ll save on electricity usage and costs, too.

Use Eco-Friendly Detergent
Seventh Generation and Trader Joe’s, among others, offer automatic dishwasher detergent free of phosphates that can cause algae blooms in lakes that can suffocate acquatic plants and animals; free of chlorine bleach, which creates dangerous toxins that are linked to (scary!) cancer, birth defects, and developmental and reproductive disorders; and free of dyes and artificial fragrances that can irritate children and sensitive adults. While they might not save you energy, you’ll get bonus eco points for choosing them.