Contact lenses are disposable, a word that is not usually synonymous with sustainability. But eyeglasses are made out of metal and other materials that
Archive for November, 2010
Dear Pablo: Which is more sustainable, eyeglasses or contact lenses?
Contact lenses are disposable, a word that is not usually synonymous with sustainability. But eyeglasses are made out of metal and other materials that also have a certain environmental footprint. Which is the more sustainable choice?… Read the full story on TreeHugger
Image Source: Mike Deal
Dear Pablo: I am still holding out on getting new LED holiday lights because I feel bad about getting rid of the ones that I already have. Are the energy savings worth it?
Many of us have a tangled mess of holiday lights in a box in the attic. Every year we bring it out, untangle them, spend hours searching for the one burned out bulb, and hang them on our houses. In addition to all of this effort, the lights use a lot of electricity. You would be surprised by how little of the electricity actually gets turned into light…. Read the full story on TreeHugger
Dear Pablo: I have heard claims that canned beer is more sustainable than bottled. I find it hard to believe that metal is better then glass. Can this be true?
Is Aluminum Better Then Glass?
Pound for pound aluminum is much more energy intensive to mine, refine, process, transport, and shape into beer cans than glass is, so how can it be more sustainable? There are two reasons for this; weight and recycling. Aluminum cans use a lot less material than glass bottles to contain the same about of product (15 grams vs. 170 grams). So, even if the aluminum cans were ten times as energy intensive as glass bottles to produce, the cans would still represent a lower overall impact. Recycling rates for aluminum are much higher than for glass and in many locations glass “recycling” is a myth anyway. Glass is essentially made from sand and it is often cheaper for a bottle factory to make bottles from virgin material that paying to have the recycled bottles trucked all the way back to the plant. Even if the bottles are recycled, the energy required to melt the glass is virtually the same as for virgin material. When it is recycled aluminum has a much lower impact than virgin aluminum because it eliminates the mining, refining, and processing stages of the material lifecycle…. Read the full story on TreeHugger