dirty laundry

In addition to flushing clean water down the toilet, we use it to wash our clothes. Approximately 15%-25% of daily water use goes into laundry according to some sources. A top rated energy saving washing machine uses as much as 5,000 gallons of water per year or about 14 gallons a day according to Energy Star ratings. Energy Star ratings are issued by the government and assume a healthy amount of washing. Actual numbers are probably a bit lower, although you never know. A recent UK study found that the average UK household uses 21 liters or 6 gallons a day to do laundry.

Washing machines maybe practical but they are enormously inefficient. According to the same British study, a washing machine uses about 35 liters (or 35 kgs) of water for every kg of laundry. I am assuming this refers to front-loaders that are ubiquitous in Europe. Front-loaders use a lot less water than the more common top-loaders favored in America. Hey, we live in the desert so why worry. Whereas front loaders spin the wash through a layer of water at the bottom, top-loaders soak the entire tub. In doing so they use 3-4 times as much water.

It doesn't stop there. All that water has to be pumped and heated and that is no small matter. Water is heavy and it has some of the highest heat capacity of any commonly used substance. Calories, a measure of energy are defined as the amount of energy it takes to heat 1g of water by 1 degree centigrade. To heat 35 kgs of water by 35 degrees takes 1,225 kcal or 4,800 BTU. But that is only half the story. Once the wash is done, people use even more energy to get those same clothes to dry.

Although most households in the US have ample sunlight to dry clothes, nearly everyone these days uses a dryer. In some communities, hanging one's laundry to dry is against home owner association rules. God forbid that the neighbors would have to look at your laundry. That is simply not acceptable. Much better to waste tons of energy to dry your clothes. This is, after all, the land of plenty. The added benefit of course is that your clothes won't last as long, which is good for business too. But let's turn to more sensible approaches.

I read today that a UK company, spun out of Leeds University plans to introduce a "waterless" washing machine. The machine uses as little as one cup of water to run a load of laundry. The magic ? Plastic chips ! The company is appropriately named Xeros, derived from the Greek word dry, and it plans to start selling machines next year. The added benefit is that your clothes won't be wet so there will be no need to use the dryer or to face the ire of the neighborhood moral enforcers. It remains to be seen how successful the machine will be. So far, all we have is a press release.

Given that major cities like Barcelona in Spain are now forced to ship in water by boat, and that entire provinces in Spain are drying up and becoming part of the Sahara's northward expansion, this is a timely invention. Hopefully Americans will be smart enough to import these machines should they become successful in the UK and Europe. Until then, try to conserve water if you can. Experts predict it will be the next battleground.