Paper or Plastic?

I have always had the vague idea that paper bags were more environmentally friendly than plastic ones, but I never really had any facts to back up my intuition. Well, a great resource for such questions is the Institute for Lifecycle Environmental Assessment (ILEA), which is dedicated to finding out the lifetime environmental costs of consumer goods. The lifetime costs include

• The energy required to produce the product.


• The pollution created by the manufacturing process.


• The pollution produced by use of the product.


• The costs of disposing of the product.

The ILEA analysis of paper vs plastic:

Franklin and Associates completed a life-cycle energy analysis comparing the two common grocery bags. There were two critical measures. The first is the total energy used by a bag, which includes both the energy used to manufacture a bag, called process energy, and the energy embodied within physical materials, called feedstock energy. The second measure is the amount of pollutants produced. Using energy and pollutants from all stages of a bag's life, both measures result in favor of plastic bags.

The ILEA website has articles discussing electric vs. gasoline cars, manufacturing vs use costs for automobiles, cloth versus disposable diapers, reusable versus disposable cups.

That last item is a real eye-opener. Reusable cups made of ceramic, plastic, or glass require vastly more energy to produce than a disposable cup made of paper or styrofoam. In addition, every time you wash a reusable cup, it requires resources (energy, soap, and clean water). The ILEA calculates a "break-even" point for various types of cups, which is the number of times the cup must be reused before it is more efficient than using disposable cups. For ceramic mugs, the break-even point is 1006 uses. For glass cups, it is only 393 uses.

So roughly speaking, if you are so clumsy that a glass cup lasts less than a year before it is broken, you would be better off using disposable cups (styrofoam).