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Waste Prevention
Saves Energy
H.J.H. Whiffen, J.F.K.
Earle, M.S. Hammer
TRASH TROUBLE
Garbage, waste, rubbish, trash--we, the
people, are producing too much of it. On the average, a Floridian generates
8.3 pounds of solid waste every day, 4.7 pounds more than the national average
estimated by the Environmental Protection Agency (EPA) (State of Florida
Department of Environmental Regulation, 1991). The municipal solid waste (MSW)
found in the home and office garbage can is a product of natural resources
used to manufacture it. This includes energy resources both as a base
materials (feedstock) and as power for processing and transportation. The
mining, refining and consumption of these energy resources creates a variety
of pollutants. Given this information, it is easy to see how MSW is a triple
whammy.
- natural resources are used up,
decreasing the quantity of these irreplaceable materials,
- energy is consumed, leaving less for
the future while creating more pollutants and increasing the potential for
global climatic change, and
- efforts at MSW disposal are
contaminating the environment in which we live.
There are three major methods of dealing
with the solid wastes generated: landfills, incineration and recycling. Each
method has capacity limitations (Table 1 ). Therefore,
the best means of subduing the problems associated with MSW is to reduce the
amount of MSW created.
THE FIRST LINE OF DEFENSE
Source reduction, also called waste
minimization, is an abatement of waste propagation, a decrease in the amount
of garbage generated per person per day. It is pollution prevention activities
of manufacturers and consumers aimed at reducing the toxicity or quantity of
products before they are purchased. This factsheet discusses opportunities for
consumer waste prevention. Source reduction decreases:
- the land area in the state that must
be committed to landfills,
- the rate of natural resource
depletion, and
- the quantity of pollutants generated
during commodity production, use and disposal.
When fewer products are manufactured, less
energy is consumed to make and transport them and ultimately, less energy ends
up in the garbage can. Some waste minimizing strategies are listed in Table
2 .
EXPENDING ENERGY
In 1984, people in the United States
discarded 59.6 billion pounds of paper packaging (Selke, 1990). Approximately
660 million trees for paper pulp were harvested and the energy equivalent to
17 billion gallons of gasoline was consumed in the processing and
transportation of this paper packaging. Seventeen billion gallons of gasoline
could keep the 60-watt light bulb on your back porch lit for over 400 million
years. In 1987, 4.4 billion pounds of plastic film were thrown away in the
United States (Selke, 1990). The production of this plastic consumed the
energy equivalent of 2.8 billion gallons of gasoline. This same energy could
have run your 20-cubic foot refrigerator continuously for over 5 million
years. If source reduction measures were used to decrease the amount of
plastic and paper packaging used by 10 percent, 6.4 billion pounds of MSW
would be removed from the waste stream and the energy equivalent of almost 2.0
billion gallons of gasoline would be conserved. Two billion gallons of
gasoline is greater than the energy it takes to operate your television for
170 billion hours. One hundred and seventy billion hours is over 650 million
years of Star Trek reruns.
OPERATION SOURCE REDUCTION
Source reduction is about making choices
365 days a year at home, at work, in the car, and at the store. Any reduction
in the amount of MSW generated by one individual is a successful waste
minimizing mission. The following provides descriptions of a few source
reducing game plans that illustrate the enormous energy and resource savings
and environmental benefits that can accrue from the actions of concerned
citizens.
Juice: Buy the Gallon
A household of four people can drink more
than 45 gallons of Florida orange juice in one year, if each person drinks a
typical 4-ounce serving with breakfast every morning. Unless this orange juice
comes from freshly squeezed, backyard oranges, it must be purchased in some
type of container at the grocery store. Orange juice can be purchased in
16-oz, 32-oz, and 64-oz wax-coated paper containers. The selection of
container size significantly affects the energy and environmental impact of
the purchase (Table 3 ). Buying 45 gallons of orange
juice during the year in 64-oz containers costs $272, while buying 45 gallons
of orange juice in 16-oz containers costs $433. Therefore, buying orange juice
in bulk can save $160 annually. In addition, since bulk buying reduces the
quantity of containers used per fluid ounce, buying orange juice in bulk can
save enough energy to power the hall night-light for 490 nights (Table
4 ).
The Sanctioned Sack Lunch
A sack lunch sandwich can be packaged in a
variety of ways: aluminum foil, a ziptop baggie, or a plastic sandwich box.
The energy required to make these containers differs depending upon the
material type and the amount of recycled fibers used (Table
5 ). Generally, when packing lunches using aluminum foil or baggies, new
foil or a new baggie is used every day. By comparison, plastic sandwich boxes
can be reused repeatedly. When a sandwich is packaged in a plastic sandwich
box instead of aluminum foil or plastic baggies, over 80 percent of the energy
used for sandwich containers is saved. This can lead to big savings over the
course of a school year. There are approximately 185 days in a school year. If
one student's sandwich for lunch is packed in a plastic box instead of a
ziptop baggie, the family saves $15 on sandwich wrappers, because one plastic
box can be used all year. There were 165,375 students in the 1990-91 first
grade class in Florida. If the sandwich for each student was packaged in a
plastic sandwich box for the school year instead of baggies the energy
equivalent to over 125,000 gallons of gasoline would be saved annually. The
energy in 125 thousand gallons of gasoline could run a stereo for more than 19
million hours. Nineteen million hours is 2,231 years of continuous stereo
sound.
Paper Consumption at the Copier
In an office of 50 people, it is easy to
imagine the office copier making 500 copies per day. If all 500 copies per day
are one-sided, energy equal to 430 gallons of gasoline is consumed at the
paper mill to make the 1,250 pounds of paper per office per year. Many copy
machines are able to make double-sided copies automatically. If half of the
copies made in only one office were double-sided, the office would save $150 a
year, because it would save 65 reams of paper annually. At the same time, 300
pounds of waste paper and the energy equal to 100 gallons of gasoline would be
removed from the waste stream annually. The energy in 100 gallons of gasoline
could power a computer for 434 work days.
Individually Wrapped Cheese Slices
The marketing wizardry of the cheese
industry has created a wide range of consumer choices at the supermarket.
Three of these options are:
- individually wrapped cheese slices
packaged together with an outer layer of plastic,
- sliced cheese packaged in an outer
layer of plastic, and
- unsliced cheese packaged in an outer
layer of plastic.
Plastic wrap around each individual slice
of cheese requires that extra materials and energy be consumed by the cheese
packaging process to make, wrap and transport the cheese. The 5,145,115
households in Florida consumed approximately 67,800 tons of American cheese in
1989. If purchased as individually wrapped cheese slices, the energy
equivalent to 6.3 million gallons of gasoline was used to make the plastic
wrap for each cheese slice. 6.3 million gallons of gasoline is enough energy
to run the television and VCR for 270 million hours or 108 million movies.
The 12-oz Aluminum Can vs.the 2-Liter
Plastic Bottle
Soda can be purchased in either aluminum
cans or plastic bottles made from PET and HDPE plastics. An aluminum can holds
12 fluid ounces; a 2-liter bottle holds 67.6 fluid ounces. An aluminum soda
can can be recycled into another soda can; plastic from a soda bottle is
"downgraded" to make a non-food container or product to insure
sterile food packaging. The energy required to manufacture an aluminum can
with 50 percent recycled fibers is 80 Btu per fluid ounce. The energy required
to manufacture all the parts of a 2-liter plastic bottle with no recycled
fibers is 114 Btu per fluid ounce. Therefore, 30 percent of the energy needed
to make the soda container is saved when 12 oz aluminum cans made of recycled
materials are purchased instead of 2-liter plastic bottles. Aluminum is a
popular metal to recycle because it costs less to make a soda can out of
recycled materials than out of new metal. In 1989, America recycled 60 percent
of the 80 billion cans used. One out of every four PET bottles are currently
being recycled. PET bottles are actually a form of polyester so they can be
recycled into carpeting, suits and fiberfill for ski jackets. HDPE can become
flower pots and trash cans.
CONCLUSION
If the problem isn't fabricated, a solution
doesn't have to be found. MSW can't be completely eliminated, but the size of
the problem can be decreased through source reduction. Source reduction
includes energy conserving strategies because it takes energy to make things,
it takes energy to dispose of things, and the expenditure of energy itself
makes MSW. Some examples of how source reduction saves energy have been
illustrated in this fact sheet, but there are more energy-saving source
reduction strategies just waiting to be discovered.
Tables
Table
1.
Landfills
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Generation of
Pollutants
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Liquid pollutants
from old landfills are seeping into the groundwater. Leachate from
municipal landfills has been shown to be a significant source of
groundwater pollution.
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Methane, a
greenhouse gas with 25 times the greenhouse effect of carbon dioxide, is
being generated inside landfills and escaping into the atmosphere.
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Capacity
Limitations
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The number of
landfills in Florida is being reduced and new sites on which to build
other landfills are becoming more difficult to find in Florida, where
over 1,000 people move everyday.
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Waste-to-Energy
Incineration
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Generation of
Pollutants
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Waste-to-energy (WTE)
incineration plants burn MSW as fuel. On the average MSW has 4,500-6,000
BTU of heat energy per pound of unprocessed garbage. This energy is used
to generate steam or electricity. National studies are currently being
conducted to determine the polluting potential of these facilities.
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Capacity
Limitations
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In 1988, the nine
active waste-to-energy incineration plants in Florida burned
approximately 3,300,000 tons of MSW, 21 percent of the total MSW
generated in Florida. They produced a little over 4 percent of the
state's electrical energy consumption for the same year. The leftover
ash2 amounted to approximately 742,500 tons of landfill, a 78
percent weight reduction from the original MSW input.
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Not all MSW
generated can be burned in a waste-to-energy incineration plant. Metal
and glass products do not burn and several other materials give off
toxic substances. Source separation, a labor intensive process, is
required to minimize the pollution potential of WTE incineration plants.
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Recycling
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Generation of
Pollutants
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Recycling
consists of three different activities: collecting secondary materials,
preparing those materials for market, and recycling the materials by
manufacturing new products. All three of these activities require energy
inputs and produce pollution. It is true that, in most cases, the
manufacturing of the new products from recycled materials requires less
energy than the manufacturing of the same product from virgin raw
materials, but it is not true that recycling does not consume energy. In
some cases, i.e., liner board, box board, the energy required to
manufacture the product when recycled materials are used is greater than
when using raw materials. Also, sometimes products made using recycled
paper fibers are more fossil-fuel intensive because the non-paper fiber
parts of trees are not available to burn as fuel.
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Capacity
Limitations
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The materials
which are currently being recycled nationwide include paper products,
organic matter as compost, certain types of plastics, glass, steel-tin
cans, aluminum and used car oil and tires. In 1990, 15 percent of the
MSW generated in Florida was recycled. There are several IFAS
publications which discuss recycling options.
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Unfortunately,
not everything which is thrown away can be recycled. It is too expensive
to separate multi-material products, i.e., disposable razors,
calculators, lighters, into their base components which is a necessary
step before recycling can occur. There is also a limit to how many times
paper and plastic fibers can be reformulated into other useful products.
For other items there is simply no market for recycled materials.
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1Office
of Technology Assessment, Facing America's Trash: What Next for
Municipal Solid Waste. 1989.2Ash is the noncombustible part
of MSW.
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Table 2.
Method
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Example
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Reuse product for
original purpose.
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Store brown sugar
in an empty glass jar to keep the sugar fresh.Fill an empty pump spray
bottle with water to use as a plant mister.
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Purchase products
which have been redesigned to consume less input materials during
manufacture.
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The average
American car in 1990 weighed almost 30 percent less than its 1972
counterpart.
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Increase a
product's useful life by taking good care of it and repairing broken
parts.
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It costs much
less money and agony to get new heels and a shoe shine on a well built
pair of shoes which are already broken in and comfortable than to
purchase a new pair of shoes.
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Reduce the
consumption of products which have a negative environmental impact.
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Calculator
batteries contain mercury and cadmium. Both are toxic substances. Use
calculators with solar photovoltaic cells. They make electricity from
any light source.
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Substitute
reusable products for single-use disposable products.
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Multi-use
micromesh coffee filters eliminate the daily disposal of paper coffee
filters.
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| Table
3. Annual Orange
Juice Consumption in a 4-Member Household1 |
Wax-Coated Paper
Container Size Purchased
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Number of
Containers Purchased Annually2
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Annual Cost of
Purchased Orange Juice($)
|
Energy Used to
Make Annual Supply of Containers (Btu)
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Small (16-oz)
|
360
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428.40
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930,107
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Medium (32-oz)
|
180
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340.20
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775,089
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Bulk (64-oz)
|
90
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269.10
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581,317
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1Based
on consumption of 4-oz per person per day or 11.3 gallons per person per
year.
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2Number
of containers of given size required to hold annual consumption of 45
gallons.
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| Table
4. Cost and Energy Advantages of Buying in Bulk |
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Number
of Containers and Size Purchased
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Annual
Cost ($)
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Number
of Nights a Night-Light Could Operate on Energy Used to Make Containers
|
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36016-oz
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428.40
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1,320
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(minus)
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9064-oz
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269.10
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830
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Annual Savings
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159.30
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490 nights
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Table 5.
| Table
5. Sack Lunch Sandwich Containers |
Package
Type
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Material
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Energy
Inputs per Container per Sandwich Using 100% Virgin Materials (Btu)
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Energy
Inputs per Container per Sandwich Using 100% Recycled Fibers (Btu)
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Cost
per Student per Year ($)
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Aluminum Foil
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Aluminum
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485 per sq. ft.
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49 per sq. ft.
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5.11
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Ziptop Baggie
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HDPE1
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555 per bag
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(Footnote 2)
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16.56
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Plastic Box
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Polypropylene
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8,081 per box
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(Footnote 2)
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1.49
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1
HDPE: High Density Polyethylene2 Recycled plastic is usually
turned into things that do not have to be sterile.
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REFERENCES
Selke, S.E. 1990. Packaging and the
Environment. University of Michigan. Congress of the United States, Office
of Technology Assessment. 1989. Facing America's Trash: What Next for
Municipal Solid Waste? OTA-O-424. State of Florida Department of
Environmental Regulation. 1991. Solid Waste Management in Florida 1990 Annual
Report.
Footnotes
1. This document is
Fact Sheet EES-77, a series of the Florida Energy Extension Service, Florida
Cooperative Extension Service, Institute of Food and Agricultural Sciences,
University of Florida. Publication date: May 1992. 2. H.J.H.
Whiffen, Former Agricultural Energy Specialist, Florida Energy Extension
Service; J.F.K. Earle, Assistant Professor, Agricultural Engineering Dept.; M.S.
Hammer, Professor and Extension Home Environment Specialist, Home Economics
Dept., Cooperative Extension Service, Institute of Food and Agricultural
Sciences, University of Florida, Gainesville FL 32611. The Florida Energy
Extension Service receives funding from the Florida Energy Office, Department of
Community Affairs and is operated by the University of Florida's Institute of
Food and Agricultural Sciences through the Cooperative Extension Service. The
information contained herein is the product of the Florida Energy Extension
Service and does not necessarily reflect the views of the Florida Energy Office.
Florida Cooperative Extension Service /
Institute of Food and Agricultural Sciences / University of Florida / Christine
Taylor Waddill, Dean
Disclaimer
The use of trade names in this publication is
solely for the purpose of providing specific information. UF/IFAS does not
guarantee or warranty the products named, and references to them in this
publication does not signify our approval to the exclusion of other products of
suitable composition.Path:
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