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Charles E. Ophardt, Professor of Chemistry, Elmhurst College, Elmhurst, IL 60126, charleso@elmhurst.edu, Copyright 2004
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OBJECTIVES:
1. Calculate/estimate the fossil fuel energy resources that you or your household uses on a yearly basis.
2. Calculate the carbon dioxide that you contribute to the atmosphere as a result of using fossil fuels.
3. Appreciate the fairly large amounts of resources needed to support your life-style.
In this exercise, you will be introduced to various energy resources which are used to support the lifestyles that we are accustomed in the United States. You will calculate the amount of energy resources that you personally use, which then result in the production of carbon dioxide - a greenhouse gas.
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Use the following forms to track your use of fossil fuels. At the end of the exercise there will be a place to post the results of your fossil fuel use to an appropriate place on the CHM 110 Discussion Board. This will be worth an additional 6 points for this topic only. Write out answers to questions in a WORD PROCESSOR |
MAJOR ENERGY RESOURCES USED IN THE UNITED STATES
Graphic #1
82 quads in BTU's per year consumed in the U.S.
One BTU is defined as the heat energy needed to change 1 pound
of water 1 degree Fahrenheit.
One Quad = Quadrillion is 1 x 1015.
This large amount of energy represents 35 % of the energy used
in the world by 5 % of the population.
What is the major fossil fuel that supplies the majority of the
energy in the U. S.?
Keep a record of all the gallons of gasoline purchased for your
car for one or two weeks and prorate for one month.
TOTAL GALLONS/MONTH: _________ TOTAL GALLONS/YEAR ___________
If one barrel of oil contains 42 gallons, how many barrels of
oil do you burn in gasoline per year?
BARRELS OF OIL as gasoline /YEAR ________
15.7 Million (15.7 x 106) barrels of oil consumed per DAY - 1984
As you can see from the pie chart almost half of a barrel of oil
is used to make gasoline, which is consumed mainly in private
automobiles.
Electricity is measured in terms of kilowatt-hours. Take a look
at an ordinary light bulb and you will notice that the number
of watts is indicated. For example, the bulb may read 100 watts
or 75 watts. The wattage marked on the bulb indicates the amount
of electricity that the bulb will use in one hour. For example
a 100 watt light bulb will use 100 watts in 1 hour and 1000 watts
in 10 hours. A kilowatt-hour is equal to 1000 watts. If you burn
10 light bulbs of 100 watts each for one hour, you have used 1000
watts in one hour or one kilowatt-hour.
If you look carefully at various appliance motors or the instruction
manuals, you may find the wattage listed.
On a typical evening go around your house OR dorm room and floor
and make a list of all the lights turned on along with the wattage
for the bulbs. A four foot fluorescent tube (usually two per fixture)
is 40 watts. Also list the amount of time each light is turned
on in quarter fractions of an hour. Multiply the watts times the
time in hours, and finally add them altogether. Convert the watts
per hour to kilowatt-hours.
Week Night Lights: _________________kilowatt-hours
Use your monthly electric bills to tabulate monthly and ultimately
yearly use of electricity. Find as many bills as possible. There
will be differences in the amounts in summer to run air conditioning,
winter to run the furnace, and spring/fall when neither is used
very much. If you live in an apartment or dorm, try to obtain
this information from family, friends, or relatives that live
in a house or you may access data from a typical suburban house
Utility Usage.
AVERAGE MONTHLY ELECTRICAL USE IN KW-HRS: ____________
AVERAGE YEARLY ELECTRICAL USE IN KW-HRS: ____________
Energy Sources Used to Generate Electricity
2.5 trillions (2.5 x 1012)KW-HRS. consumed in U.S. - 1985
Which is the major fossil fuel used to generate electricity?
What is the major energy source for space heating? Which source
do you have in your house?
What source of energy is used to heat water in your house? natural
gas or electric?
What source of energy is used for the clothes dryer? natural gas
or electric?
Use your natural gas (or fuel oil) bills to find the
cubic feet of natural gas used for an entire year. Actually there
is no longer any reference on the bill to cubic feet of gas, but
the number they do provide is Therms of gas. These two terms and
numbers are nearly equivalent. The number of Therms given must
be multiplied by 100, since it actually represents 100s of cubic
feet of natural gas. One barrel oil = 7700 cubic feet natural
gas equivalent. If you live in an apartment or dorm, try to obtain
this information from family, friends, or relatives that live
in a house or you may access data from a typical suburban house
Utility Usage.
CUBIC FEET NATURAL GAS/YEAR __________
Carbon Dioxide Emissions
Chemical Calculations: How much does each person contribute
to the production of excess carbon dioxide by driving an automobile
and using 1 gallon of gasoline to drive 20 miles?
Please Note: No actual calculations are required from you,
just follow along and appreciate that this is how chemical calculations
are completed.
An automobile burns gasoline in the combustion reaction. Although
gasoline is a complex mixture of organic compounds, this problem
will focus on one of them, octane - a hydrocarbon, (C8H18). Other
information needed to solve the problem includes: 1 gallon = 4
quarts; 1 quart = 960 ml; density of octane = 0.69 g/ml
a. How many quarts in a gallon? (ans. 4 qt)
b. How many milliliters in a gallon? (ans. 3840 ml)
c. How many grams in a gallon? (ans. 2650 g)
d. The balanced combustion reaction for octane is:
2 C8H18 + 25 O2 ===> 16 CO2 + 18 H2O
All combustion reactions of any fossil fuel produce carbon
dioxide and water as by products.
e. What is the mole ratio of octane to carbon dioxide by reading
balanced equation?
2 moles octane = 16 moles CO2
f. What is the molecular weight of octane? of carbon dioxide?
1 mole octane = 114 g; 1 mole CO2 = 44 g
g. Calculate the mass of carbon dioxide produced.
| 2650 g X | 1 mole octane X | 16 moles CO 2 X | 44 g CO 2 = |
or 8.18 kg/gal |
| 114 g octane | 2 moles octane | 1 mole CO2 |
To find the totals simply multiply the yearly totals
from the Inventories by the factors listed below.
| Energy Use | Yearly Use | CO2 factor |
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| Transportation: Automobile: |
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| Electricity: Coal Fired Electrical Power Plant: |
per 1 kilowatt hour |
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| Natural Gas: | 0.062 kg carbon dioxide per 1 cubic feet natural gas | ||
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2.2 lbs. = 1 kg... in pounds 2000 lbs = 1 ton... in tons |
Compare your contribution of carbon diioxide to the total U.S. for 2002.
Write out answers to questions in a WORD PROCESSOR
and then copy and paste into Blackboard
Post your information on the Discussion Forum. Use the info given to ultimately type your data into the message box. We want to find how who is the energy miser and who uses the most energy.
After completing this energy assessment, hopefully you will have an appreciation for the amount of carbon dioxide that is produced from the combustion of fossil fuels as you begin the Issue # 3 Discussion. As part of that discussion, the issue will be how to reduce the amount of carbon dioxide produced from fossil fuels.
| Use the Personal Environmental Impact Calculator to find all of the gas emissions related to energy useage. Try Transportation and Energy (household usage). List the total results for CO2, CO, Hydrocarbons, and NOX. Include these when you post the other results to the discussion board. | |
| Extra Credit: 1 point each for transportation and energy | Personal Environmental Impact Calculator |
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Use the EPA guide for automobiles to calculate your
GHG Emissions (Greenhouse Gas): For example a 2000 Buick Regal produces 8.2 tons* of GHG per
year. |
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| Extra Credit: 1 point for a car. | GHG Emissions Calculator |
