Monday, March 1, 2010

The "Cost" of a Drink of Water

by Shelly Sargent

After a while, most of us become comfortable with the "basics" of living a responsible green life. We get good at recycling and composting, simplify our lives, buy products that won't harm the environment. We avoid over-packaged goods, recharge our batteries, walk as much as possible, wash in cold, dry on the line and switch to eco-friendly light bulbs.

It may take some time, but sooner or later, we end up having done most of the simple things that are available to us and start looking around for new "eco-mountains" to climb.

And I suppose that is why - lately - I find myself pouring over "green" websites. I've been looking for new (and easy) green initiatives to put into practice. As I find them, I'll try to remember to share here - it is nice to find out about simple actions which will reduce our energy footprints. It's even better to find out WHY these thing are better for the environment.

In my recent "virtual" travels, I found some every interesting pieces of information that made me re-think the way I go about getting a cold glass of water. We all know bottled water is bad news (using as much as 2000 times the energy to produce as tapwater does, according to ScienceMag.com). So we all agree that we should drink plain old tap water. But did you know there are a multitude of ways to get yourself a simple glass of water, some of which are way better for the environment than others?

The question is - should you run the tap until the water is cold before you fill your glass, or fill your glass with "room temperature" tap water then dropin a couple of ice cubes from the freezer? Or should we simply keep a container of cold water in the fridge, ready for drinking whenever we need it.

Of course we know that that all three methods have an "eco-cost" (pretty much everything does). Tap water must be treated, pumped and stored - all things that use energy. And making the water nice and cold means we have to find a way to cool it. Refrigeration uses power, freezers use even more. So running the tap to make water cold is the best way, right? WRONG!

But I was a bit surprised to find out that - of all the options above - running the tap is apparently the worst waste of energy and the pitcher of water in the fridge wins out over the other options.

Remember mom yelling "Shut the fridge door before you let all the cold out!" ? She was right. Refrigerators waste energy every time the fridge door is opened and cold "escapes" to be replaced with warmer room air. The longer the door is open, the more energy it takes to get the fridge cold again. They say that each time the fridge door is opened for a few seconds, up to 1.4 watts of electricity is used. Freezers use just about double that amount (about 2.8 watts of electricity) when the door is opened. Running the tap to get to cold water wastes water AND wastes the energy used to treat, pump, and deliver it. It is estimated that for each gallon of water running out of your kitchen tap, you "spend" about 1.5 watts of power. It doesn't take long to run a couple of gallons of water to "get to the cool stuff".

So on that level alone, keeping a pitcher of water in the fridge is the most energy efficient option of the three. But there is also a "bonus" reason: a fridge full of cold foods and drinks maintains its internal temperature easier than an empty fridge. So that large container of cold water helps do the job!

So there you have it... the eco-friendly way to have a drink... and a few of the reasons why!

Sources: Blueegg.com & ScienceMag.com