investigating efficiency
and vehicle emissions
Grade 12, Physics, College Preparation, SPH4C
description
This activity builds off the concepts introduced in Getting Outdoors with Physics. It involves the collection and analysis of
real-world data to explore vehicle efficiency and how that translates into CO2 emissions. Students will measure commuting
distances and compare highway and city driving.
curriculum links - physics, grade 12, college preparation, sph4c
Overall Expectation: E1
Specific Expectations: E1.1, E1.2
planning notes
Background Information
Energy can be transformed from one form to another;
however, systems involving energy transformations are
never 100 percent efficient. The different processes used
to generate usable energy vary in efficiency, as well as in
the amount of GHGs they produce. As a result, different
energy sources (e.g., coal, petroleum, natural gas, hydro,
nuclear) and their resulting energy transformations affect
the environment in different ways. Less efficient processes
produce high levels of carbon compounds, and more
efficient processes produce lower levels of gaseous carbon.
Increased efficiency is a factor in reducing the production of
GHGs and a device’s efficiency can be measured in terms of
the size of its carbon footprint.
Materials/Resources
• Graph paper
• Vehicle Information Chart (Appendix 1)
• Examples of Fuel and Commute Calculations (Appendix 2)
Recommended Class Time
2 periods + at home activity
teaching/learning strategies
Ignite
1. In preparation for this activity, ask all students to complete Vehicle Information Chart (Appendix 1) using their family
vehicle or another vehicle of their choice. Ask a class, discuss how to calculate/estimate the ratio of highway to city driving in
their commute.
2. As a class, explore Overall Equipment Effectiveness (OEE) and fuel consumption ratings tools online so that students
are able to access the necessary information to complete their work.
Explore
1. Ask students what they found out about their vehicle and the OEE ratings. Discuss what factors impact efficiency of
vehicles and carbon dioxide emissions (CO2) from vehicle, including energy transformations, internal combustion, and
engines.
2. Using the Table 2 on Examples of Fuel and Commute Calculations (Appendix 2), ask students to calculate the amount of CO2
emissions that their vehicle produces during a round trip commute to school. Ensure that students estimate and account
for the relative proportions of city driving and highway driving.
1
Investigating Efficiency and Vehicle Emissions
3. From there, have the entire class choose either city or highway driving (depending on where your school is located) and
calculate the amount of CO2 that their vehicle produces for a 10 km drive.
4. Ask students to share their information about how much CO2 is produced during a 10 km drive with a small group. Using
that information, students can create a graph comparing the vehicles and CO2 produced from driving 10 km. (If necessary,
add examples for vehicle types that are not represented in the class, i.e. large vs. small, newer vs. older, etc.)
5. After graphing the data, ask each student to select the most efficient vehicle and calculate how much CO2 would be
produced by a year’s commute. Decide on an average commute time as a class and assume that there are 196 days of
school. Then, repeat the calculations using the least efficient vehicle.
6. Explain that according to the UNEP an average tree absorbs 12 kg CO2 per year. Using the example provided in Table 2,
ask students to calculate the amount of trees needed to offset their year commute.
Reflect
1. As a class, examine the graphs and share any observations. Discuss the following questions and highlight any factors
that might impact efficiency.
• What do you notice about the least and most efficient vehicles?
• Do they have anything in common?
• Why do you think some vehicles are more efficient than others?
• Does driving on the highway versus the city make a difference?
2. From there, discuss the difference between the yearly CO2 produced from an efficient vehicle versus an inefficient
vehicle. Why do consumers continue to buy inefficient vehicles? What advantages do they have over efficient vehicles
that keep them on the market?
3. In small groups, discuss ways to make inefficient vehicles more efficient. Share your ideas with the class and then work
together to create a series of recommendations for manufactures.
extension
Calculate Yearly Commutes: Using the information gathered in class, students can calculate the price of gas for a yearly
commute. Students can figure out many trees would be needed for the entire class’ yearly commute and then expand this to
the whole school.
appendices
Appendix 1 – Vehicle Information Chart
Appendix 2 – Examples of Fuel and Commute Calculations
2
Investigating Efficiency and Vehicle Emissions
appendix 1
INVESTIGATING EFFICIENCY AND VEHICLE EMISSIONS
VEHICLE INFORMATION CHART
Vehicle Details
Example
Make
Mazda
Model
Protégé
Class
C – Compact
Year it was made
2003
Fuel Consumption
City
9.3 L/100km
Highway
6.9 L/100km
CO2 kg / year
(assuming 20,000 km
driven at 2.3 kg of CO2)
3880 kg of CO2 / year
Home-School Commute
Km driven to
school
10 km
Km driven to
school and back
20 km
Type of Commute
Estimate % of highway driving (fast, consistent) vs. city driving (slow, stop & go)
3
% Highway
20%
% City
80%
Investigating Efficiency and Vehicle Emissions
appendix 2
INVESTIGATING EFFICIENCY AND VEHICLE EMISSIONS
EXAMPLES OF FUEL AND COMMUTE CALCULATIONS
Table 1
Explanation
Example
Calculate the mass (in kg) of CO2
produced by 1 L of fuel.
1644 L of Fuel = 3880 kg of CO2
1 Year
1 Year
1644 L of Fuel = 3880 kg of CO2
Inputs (from website, using the
2003 Mazda Protégé as an example):
• Fuel Consumption = 1644 L/ year
• Emissions = 3880 kg of CO2 / year
1644 L of Fuel = 3880 kg of CO2
1644
1644
1 L of Fuel = 2.360 kg of CO2
Determine the proportion of city
and highway driving.
Highway commute =
20 % of 20 km
= 20 * 0.2
= 4 km
Example inputs:
• Round-trip commute = 20 km
• 20% highway & 80% city driving
Calculate the fuel consumption
of the commute.
Inputs (from website, using the
2003 Mazda Protégé as an example):
Fuel Efficiency:
• 6.9 L /100km–Hwy driving
• 9.3 L /100 km–City driving
City commute =
80% of 20 km
=20 *0.8
= 16 km
Highway commute
City commute
6.9 L of Fuel
100 km
9.3 L of Fuel
100 km
0.069 L of Fuel
1 km
0.093 L of Fuel
1 km
0.069 L of Fuel
= *4 km
km
0.093 L of Fuel
= *16 km
km
=0.276 L of fuel
=1.488 L of fuel
Total Fuel Used:
= Highway commute + City commute
= 0.276 + 1.488
= 1.764 L of Fuel
Calculate the mass (in kg) of CO2
produced during the daily commute
Total L of fuel used * kg of CO2/ L of Fuel = Total Emissions
1.764 L of Fuel * 2.360 kg of CO2/ 1 L of Fuel
= 4.163 kg of CO2 emissions produced during the daily commute
Table 2
Calculate the mass of CO2 (kg) produced
from your yearly commute
= 196 days/school year *4.163 kg of CO2/day
= 816 kg of CO2/school year
Example Input:
• 196 days in a school year
• 4.163 kg of CO2 produced during the daily
commute (from previous example)
Calculate the amount trees needed
to offset your yearly commute.
Inputs
• An average tree absorb 12 kg CO2
per year as per UNEP
• Emissions produced: 816 kg of
CO2 produced during a year’s commute
4
816 kg of CO2 produced during yearly communte
12 kg of CO2 absorbed by one tree per year
= 68 average trees are needed to absorb
the emissions from your commute.
Investigating Efficiency and Vehicle Emissions