What Is A Carbon
Footprint?
A footprint is a mark you leave by walking. The way you live also leaves a mark. Many things we do in life,
such as producing energy, driving cars and raising livestock, generate gases that contribute to climate change.
And almost all of these gases are carbon compounds. That’s why the effect your life has on creating these gases
is called your carbon footprint.
To find your own footprint go to:
http://www.carbonfootprint.com/calculator.aspx
At the end of the calculation, fill out the following:

Your footprint is ___________ metric tons per year

The average footprint for people in United States is ___________ metric tons

The average for the industrial nations is about ________ metric tons

The average worldwide carbon footprint is about ________ metric tons

The worldwide target to combat climate change is________ metric tons
How do you compare to the rest of the United States?
How do you compare to the rest of the world?
Why do you think the worldwide target is so low?
Did you know that plastic bottles have their own carbon footprint?
The Pacific Institute, a non-profit research organization, estimates that the energy used in the production and
use of plastic bottles, such as water bottles, is equivalent to filling the plastic bottles one-quarter full with oil.
Oil affects global warming by producing high quantities of greenhouse gases when it is burned. The
manufacture of one pound of PET -- polyethylene terephthalate -- plastic can produce up to three pounds of
carbon dioxide. Processing plastic resins and transporting plastic bottles are major contributors to a bottle's
carbon footprint. The Beverage Industry Environmental Roundtable estimates that one 500-milliliter (0.53
quarts) plastic bottle of water has a total carbon footprint equal to 82.8 grams (about 3 ounces) of carbon
dioxide.
1. Transportation of Raw Materials
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Plastic bottles are made of resins derived from oil or refined petroleum and natural gas. Refined
petroleum and natural gas are sometimes transported long distances to the plastic manufacturers,
using fossil fuel and producing emissions of greenhouse gases. The size of the carbon footprint
depends on the mode of transportation and the distance raw materials have to travel. For
example, truck transportation causes more carbon dioxide emissions than rail shipping. When
long distances are involved, transportation energy expenditures can approach that of plastic
manufacturing and can represent as much as 29 percent of a plastic bottle's carbon footprint.
Making Plastic Resins
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The manufacture of plastic resins is associated with the greatest amount of carbon emissions,
according to the U.S. Environmental Protection Agency. During processing, hydrocarbons in
petroleum and natural gas are heated to extremely high temperatures to break down the large
hydrocarbon molecules into smaller ones. The small hydrocarbons are then combined in different
ways to make various types of plastic. PET resin, resembling grains of rice, is the source material
for plastic PET bottles. The energy to produce PET resin represents about 30 percent of the total
carbon footprint of a 500-milliliter plastic bottle.
Plastic Bottle Production
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Energy is needed to convert the plastic resin into plastic bottles. Plastic resin, such as PET resin,
is melted and injected into a mold, and then heated and formed into the desired bottles. This final
process represents about eight percent of a plastic bottle's carbon footprint.
Other Variables
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o
Cleaning, filling, storing and packaging plastic bottles also uses energy. Waste generation,
including carting plastic bottles to landfills, add to the plastic bottle's carbon footprint. The total
of these processes can represent 33 percent of the plastic bottle's carbon footprint.
Given that production of plastic resin is usually the major contributor to the carbon footprint of a
plastic bottle, recycling can reduce the carbon dioxide and other greenhouse gasses by an
estimated 30 to 70 percent. Other methods to reduce the carbon footprint are to use less plastic
for bottles, making a lighter bottle, reducing transportation distances and other energy intensive
processes. Research into other types of plastics and material that is not derived from fossil fuel
could lead to a smaller carbon footprint of the plastic bottle.