You're Eating More Energy Than You Think!
Adapted from A-way with Waste: A Waste Management Curriculum for Schools, 2nd ed., by State of Washington, Dept of Ecology
Trash Goes To School
Cornell Waste Management Institute
SUBJECT AREAS: home economics, math
CONCEPT: Every product we make or use has "hidden" energy and environmental costs.
OBJECTIVE: Students will understand that different forms of packaging require different amounts of energy.
MATERIALS: several products to analyze
handouts: Tables 1 and 2, Table 3
KEYWORDS: calorie, British Thermal Unit (BTU)
BACKGROUND: About 1550 calories are needed to make the aluminum can that holds diet soda. Zero calories are in the soda, so...if you wanted to get maximum energy, you would eat the can!
The unit of heat used in science is the calorie (cal.), also called gram-calorie or small calorie. It is defined as the amount of heat energy needed to raise one gram of water 1 degree centigrade.
In nutrition, the unit of food energy is the Calorie (Cal.), also called kilogram-calorie, or great calorie. It is defined as the amount of heat needed to raise one Kilogram of water 1 degree centigrade. It is equal to 1000 calories.
The small c, capital C difference is important. Only the nutritional calorie uses capital C.
Engineers use a different heat energy standard called the British Thermal Unit (BTU). It is defined as the amount of energy required to raise one pound of water 1 degree fahrenheit. One BTU = 252 calories.
1 pound = 454 grams
degree C = 5/9 (degree F - 32)
1 kilogram = 2.2 pounds
1. Using information from Table 1, determine and compare the energy necessary to package the sample foods.
2. In Table 2, fill in the price (current value) of the foods and compare the prices with the amount of energy required.
3. Determine the amounts of energy required for the individual containers. Where necessary, divide the energy per pound by the correct weight of the container being examined.
4. By referring to Table 3, discuss the environmental impacts of container manufacturing and disposal. Ask: What are some advantages of recycling as compared to disposal in a landfill (saves disposal costs, conserves energy, reduces waste of nonrenewable resources).
What are some different types of packaging commonly used for your favorite foods?
Which packaging material uses the most energy to produce? Least?
How can we, as careful consumers, reduce waste and the use of energy and resources while we consume?

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