Download Kill-A-Watt EZ - Frost Middle School

Well done unit! Consider the suggestion in the Engage part of the lesson --- or not.
Unit #2: Reduce Your Carbon Footprint
Lesson Overview:
This unit on carbon footprint reduction is designed to encourage all students, including the climate change
skeptics, to participate in CO2 reduction activities with their classmates, family, and community. It is best
implemented with students who have a working understanding of both climate and weather, but much of
the lesson could be broken up into stand-alone lessons or extra credit opportunities in a regular education
classroom.
The unit's original usage was in a 7-8th grade gifted/talented classroom that had recently finished the
copyrighted weather and climate module from the Battle Creek Math and Science Center. Students also
participated in the GLOBE Student Climate Research Campaign (SCRC) weather intensive observation
period (IOP) for one month and the Community Collaborative Rain, Hail, and Snow (CoCoRaHS) weather
monitoring program for the entire school year. (see resources list)
Many times, an integrated science curriculum requires a significant change in subject matter as one unit
ends and another begins. The unit was used to smoothly transition from the study of weather and climate
to the study of energy. Students were familiar with the school district's enrgy saving plan, and had
analyzed their own energy bills to determine their carbon footprint. Many were excited about being given
a chance to begin a similar energy saving campaign/carbon footprint reduction program in their homes.
During the "Engage" segment of the unit, students have the opportunity to review what they know about
climate change and realize that there has been little discussion about reducing their own carbon footprint.
When completing the "Explore" portion of the lessons, students will become familiar with the idea that
power consumption varies widely for electronic components, and that some items even use power when
turned off. During the "Explain" section of the lesson, students will learn more about how the energy is
used, and that they can reduce their energy use, save money, and reduce their carbon footprint with little
effort. After completing the initial lessons in this unit, some students were excited to take the Kill-A-Watt
EZ home for the "Extend" portion of the lesson, during which they could test their home's electrical items.
Many decided to figure out how to "earn" money by making a deal with their families to earn a percentage
of the money saved as they worked to reduce energy consumption/costs in their homes.
Learning Expectations:
 E1.2A Critique whether or not specific questions can be answered through scientific investigations.
 E1.2B Identify and critique arguments about personal or societal issues based on scientific evidence.
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 E1.2C Develop an understanding of a scientific concept by accessing information from multiple sources.
Evaluate the scientific accuracy and significance of the information.
 E5.4A Explain the natural mechanism of the greenhouse effect, including comparisons of the major
greenhouse gases (water vapor, carbon dioxide, methane, nitrous oxide, and ozone).
 E5.4B Describe natural mechanisms that could result in significant changes in climate (e.g., major volcanic
eruptions, changes in sunlight received by the earth, and meteorite impacts).
Resources: (supplied by teacher)
 Kill-A-Watt EZ, model 4460 or similar energy monitoring device
 Numbered cards to identify lab stations (1-10)
 10 plug-in 110V items of various Wattages (for classroom portion of lab)
 Computer access
 Lab Timer
 Infrared thermometers (optional)
Resources: (found in unit appendix)
 Directions for use of Kill-A-Watt EZ or the device of your choosing
 KILL-A-WATT EZ Lab - Classroom Portion (reproducible - 1 per student)
 KILL-A-WATT EZ Lab - Home Portion (reproducible - 1 per student)
Safety:
For the "Explore" lab experience at school, the teacher needs to be careful to choose electrical items that will not
lead to accidental electrical shocks. It is recommended that you do not use items that have exposed heating
filaments, such as toasters. Additionally, incandescent bulbs can become very hot, so care should be taken to avoid
their use with students who's behavior would indicate that they may injure themselves or others with such bulbs.
Also, when students plug items into the energy use testers or the testers into the wall, they can be shocked if they
are touching the metal parts of the plugs. This can be avoided by keeping the testers and the test items plugged in at
all times. It is prudent to review these safety issues with all students prior to conducting the lab, and he same rules
will need to apply when the students conduct the lab at home for the "Extend" segment of this unit.
Materials List:
The materials for this unit are expensive, but may be available from your state or local educational
authority, utility company, or Project Learning Tree. A grant was written to obtain them for our school.


Kill-A-Watt EZ, model 4460 or similar energy monitoring device
10 plug-in 110V items of various Wattages
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


Computer access
Lab Timer
Infrared thermometers (optional)
Engage: Brainstorming Activity (10-15 Minutes)
Method 1 - for students who are not particularly familiar with climate change or human contributions to climate
change.
The students have studied weather and climate change at this point in the climate change unit, and therefore should
be quite familiar with climate change. The teacher will have the students brainstorm a list of things that they think
about when they think of climate change. Conduct this part of the lesson while circulating around the room and
having the students brainstorm and share as follows: Begin the brainstorming exercise with each student working
alone for two to three minutes.
1. Each student shares answers with another student to create a unified list.
2. Students work in groups of 4 to create a unified list.
3. Teacher assists students in creating a complete class list on a display of teacher's choosing (chart
paper, chalkboard, interactive white board, transparency).
Generally, these lists created by students will include some notions of both CO2 and related human
contributions to climate change, but will not include methods to reduce human impact. At this point in the
lesson, the teacher should introduce the idea that we can reduce our CO 2 output while simultaneously
saving money. Additionally, the discussion can be guided to make it clear that, for most people, saving
money is a valued effort, even if they do not accept the data that shows that humans are contributing to
global warming with our carbon dioxide emissions.
Method 2 - for students who are familiar with climate change and human contributions to climate change. This
method should work well with students who completed unit 1 of this module.
Since students previously learned that some of the causes of climate change are linked to energy use,
complete the exercise described in method 1, above, but with this twist: instead of brainstorming a list of things that
they think about when they think of climate change, they can brainstorm a list of ways that they think their carbon
footprint might be reduced. The unified class list of ideas can be used to guide their efforts in the subsequent
portions of this unit.
Explore: Kill-A-Watt EZ lab - classroom portion (35-50 minutes)
Lab Setup - teacher information
The teacher will need to set up 5 to 10 stations, and each station should have the following items:
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1.
2.
3.
4.
A large station number (sequential numbers).
One Kill-A-Watt EZ™ 4460 energy monitor.
Directions for use of the energy monitor (preferably laminated and taped to each station).
A plug-in electronic appliance - a list of commonly used items is suggested in the lab's data chart.
Depending on the skill level and age of the students, the teacher may also need to demonstrate the use of
the monitor for the students prior to starting the lab. It is useful to have incandescent, fluorescent, and
perhaps LED light bulbs of assorted wattages for several of the stations. These bulbs can be tested while
turned on and off, if the instructor would like to get data that will help the students understand that some
electronic items do not add to the home's phantom load (amount of electricity that a home uses when
every appliance and light is turned off). If multiple bulbs are used, students may also add a column to their
lab data charts so that they can use the infrared thermometers to take temperatures of the bulb surfaces.
Later, the teacher can use the experimental data from the bulbs to illustrate the energy wasted as heat by
the incandescent bulbs as the main difference in efficiency between incandescent bulbs and the other
bulbs.
Prior to the lab, the teacher should divide the students into groups of equal size. During the lab, the
teacher will need to observe the students to know when they should rotate stations. Students should be
encouraged to answer the lab questions in their extra time at each station, and all students must learn how
to use the Kill-A-Watt EZ if they are to complete the "Extend" portion of this unit.
Safety considerations
The teacher needs to be careful to choose electrical items that will not lead to accidental electrical shocks. It is
recommended that you do not use items that have exposed heating filaments, such as toasters. Additionally,
incandescent bulbs can become very hot, so care should be taken to avoid their use with students who's behavior
would indicate that they may injure themselves or others with such bulbs. Also, when students plug items into the
energy use testers or the testers into the wall, they can be shocked if they are touching the metal parts of the plugs.
This can be avoided by keeping the testers and the test items plugged in at all times. It is prudent to review these
safety issues with all students prior to conducting the lab.
Expectations for students before and during lab
The students should read the lab procedure and the Kill-A-Watt EZ directions prior to starting the lab. They
will need more time to complete their initial measurements than the later measurements as they learn to
use the equipment. As mentioned earlier, while completing the lab, students must be sure to learn to use
the Kill-A-Watt EZ if they are to complete the "Extend" portion of this unit. They must also complete the
lab questions as a group as they conduct the lab.
Explain: (35-45 minutes)
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Students should be questioned regarding patterns that they noticed during the lab. What they should see
is that the voltages are always roughly 120V, since that is the U.S. standard. Depending on your electronic
items, they may also note that some of the items have reading of zero, and do not draw any (or enough)
energy to register on the gauge. Given a set of appropriate items, e.g. a hairdryer or portable heater,
students may also note that the wattage listed on the item does not match the readings on the sensor.
If the thermometers were used to measure the heat from the lights, the comparison between
incandescent, fluorescent, and LED lights may be made at this time as well. Students should be able to see
that the 60W incandescent light is a lot hotter than either of the other 2 bulbs that give off the same
amount of light. They should be able to infer that the extra energy required for an incandescent bulb is
wasted as heat, instead of light. Students should now be able to see that households with fluorescent
and/or LED lights can have the same amount of light while simultaneously spending much less on electricity
and reducing their carbon footprint.1
The teacher should assist the students in understanding that some items but their yearly cost can become
significant, meaning that they use enough energy to also help create a larger carbon footprint for the family
that uses those items. Examples include an alarm clock/radio that uses 50 Watts of power continuously - it
may only be 1.25 kWh of energy per day, but that cost is roughly 1.25 kWh x 13.5 cents per kWh, which
works out to be just under 17 cents per day, or $61.59 per year. Replacement of the inefficient clock with a
newer model that only uses 15 Watts continuously can reduce the annual cost to $18.47 per year, which
will quickly defray the cost of the new alarm clock and reduce your carbon footprint permanently. The
teacher can ask the students for solutions to that issue, and should lead them to solutions such as
unplugging the items, using timers on some items, switching off power strips, and installing more energy
efficient lights and appliances. 1
The teacher should go over students’ answers to the questions on the lab, guiding them to an
understanding of where they may be using excess energy or simply wasting energy in their homes.
Additionally, the term "Phantom Load" can be introduced to describe the items listed in question #9. Part
of the goal of any successful electrical usage reduction effort is to reduce the phantom load of an energy
user, and the students should have a multitude of items in their homes that can be unplugged or shut off
with a power strip when not in use.
To finish this segment of the exercise, use two podcasts from the Climate Change Minute Series by Dave
Bydlowski of the Wayne County RESA. The first podcast you will use describes the 6th of the 7 principles of
climate change, "Human Activities are Impacting the Climate System."
http://k12science.net/Podcast/Podcast/Entries/2011/11/17_Climate_Change_Minute1
1. The carbon footprint materials were purposely left off of the initial classroom segment of the lab, as
this part of the lab was intended to get students familiar with the equipment, so this is the time to
introduce the carbon footprint discussion.
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Climate_Literacy_Principle_6.html. Following the initial podcast, generate a short discussion/review of the
climate change evidence that students have seen in their weather and climate change lessons to this point.
Also, given that humans are burning the fossil fuels that are being fingerprinted as the principal cause of
increases in atmospheric CO2, it is imperative that students work to reduce their family's carbon footprint.
Following the discussion of the initial podcast and related review, move on to the final podcast for this unit,
which looks at the question-"How can we reduce the amount of greenhouse gases that humans emit?"
Students should be able to understand that their part in the reduction begins at home, with this lab and no
cost, but rather a money-saving effort for their families. Note: This is one of twenty questions that can be
found in the booklet, "What You Need to Know: Twenty Questions and Answers about Climate Change." It
is available for free at:
http://www.climatecentral.org/images/uploads/breaking/feature_faq_book.pdf
Extend: Kill-A-Watt EZ lab - home portion (35-50 minutes)
Students check out a Kill-A-Watt EZ and complete the home portion of the Kill-A-Watt EZ lab alone or in
groups as allowed by the teacher. They can determine which electronic appliances they would like to test
for this portion of the lab, and should be encouraged to test the energy usage of items that stay plugged in
at all times and are likely to contribute to the home's phantom load. They can then formulate a plan to
reduce their family's energy consumption, and subsequently their energy costs and carbon footprint.
When all students have completed the home portion of the lab, the teacher should go over their answers
and the data regarding which appliances will be unplugged or switched off should be collected from
students. At that time, the figures for energy usage reduction and carbon footprint reduction may be
calculated for each class and summed to show how easy it is to save money while helping reduce global
warming by saving energy. According to DTE, 2 pounds of CO2 are released for every kWh of electricity used (this
may vary due to the energy mix in your area). Simply sum the annualized cost reduction estimates from the
class, then divide the sum by 13.5 cents per kWh to determine the kWh savings, and then multiply that by 2
pounds of CO2 per kWh.
One saying in energy use reduction is "If it glows, it goes." As students recognize and work to reduce their
home's phantom load, they will begin to unplug or turn off items when not in use. They should be
encouraged to monitor their month-to-month energy usage as they progress forward with multiple items
identified for energy use reduction.
Safety considerations
Similar to the classroom section of this unit, the student needs to be careful to choose electrical items that will not
lead to accidental electrical shocks. It is recommended that they have parental supervision while conducting the
home portion of the lab and do not use items that have exposed heating filaments, such as toasters. Additionally,
incandescent bulbs can become very hot, so care should be taken to avoid their use with students who's behavior
would indicate that they may injure themselves or others with such bulbs. Also, when students plug items into the
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energy use testers or the testers into the wall, they can be shocked if they are touching the metal parts of the plugs.
It is prudent to review these safety issues with all students prior to conducting the home portion of the lab.
Optional extensions: Many schools now participate in school energy reduction programs. The students
can and should participate in these programs as well. At a minimum, students' contributions can include
the following: turning off lights when not in use, keeping doors shut to maintain room temperatures, and
turning off computers when not in use. One big area of concern is computers left on overnight, on
weekends, and during vacations. The Kill-A-Watt EZ can be used to test the power consumption of a
computer to help the students (and staff) to understand why they need to turn off these items. Every
dollar saved is one more dollar for educating students. Of course, there is also the added advantage of
reducing the school's carbon footprint while saving energy and money.
Evaluate: (10 Minutes)
Conduct a quiz with the following questions to determine students' overall understanding of the concepts
in this carbon reduction unit:
Carbon Reduction Quiz
Name:_________________________________________ Date:______________ Hr______
Answer the following questions in the spaces provided:
1. Explain what a home's phantom load is, and how it can be reduced.
2. Why are fluorescent light bulbs more energy efficient than incandescent bulbs?
3. Why are we implementing a plan to reduce our carbon footprint by focusing on saving money in your home?
Resources:
CoCoRaHS, the Community, Collaborative, Rain Hail & Snow network is a grassroots volunteer network of
backyard weather observers of all ages and backgrounds working together to measure and map
precipitation (rain, hail and snow) in their local communities. Home page: http://www.cocorahs.org/
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The GLOBE Student Climate Research Campaign (SCRC) aims to engage students in measuring,
investigating, and understanding the climate system in their local communities and around the world.
Home page: http://globe.gov/scrc
Climate Change Minute Series by Dave Bydlowski of the Wayne County RESA. Home page:
https://sites.google.com/site/iccarsproject/resources/climate-change-minute-podcasts.
Battle Creek Math + Science Center, 7th grade "Weather, Climate and Me" unit.
https://www.bcamsc.org/science-units/unit-summaries
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Appendix:
HOW TO USE YOUR METER
1. Turn the device on by plugging it into an outlet. Once powered, the screen should display the voltage of
the outlet.
2. Press the MENU button, this should display the total cost. If this area does not read $0.00, hold the
RESET button until it flashes and clear the data. Use the UP and DOWN buttons to scroll through the year,
month, week, day, and hourly cost to make sure that each total is $0.00.
3. Press the MENU button again, the rate should read 0.135 – which means 13.5 cents per kWh.
4. Press MENU button until you reach the Elapsed Time display, if it does not read 0:00, hold the RESET
button until it flashes and clears the data.
5. Use the MENU button to get back to the main display of voltage.
6. Plug in the device to be tested, allow some time for the device to warm up and voltage to steady so
readings are accurate. Repeat step 2 to gather the data for the next appliance on your data sheet.
**REMEMBER. . . While your appliance is plugged in and using energy, the numbers for your
readings will continue to increase, deal with it! **
7. Record your findings on the data sheet.
8. Repeat for each appliance.
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KILL-A-WATT EZ Lab - Classroom Portion
Name:_______________________________________________ Date:_________________ Hr________
The watt, named after the Scottish engineer and inventor, James Watt, is a unit used to the measure power used in
an electronic appliance. Volts are named after the Italian physicist Allesandro Volta, who appears to have invented
the first chemical battery. Volts are a measure of the "push" on the electrons moving in the wire. A Kill-A Watt EZ
device measures many things, including the watts flowing through a circuit at any given time. Based on the wattage
of an item, the Kill-A-Watt EZ can also be used to calculate the cost of running an electronic device.
Directions:
In groups of 3, you will be moving from station to station to record your findings in the chart below. Be sure to read
the directions for the Kill-A-Watt EZ, which are posted at each station for your convenience. Be sure to work on the
questions during the lab. Do not go from station-to-station until asked to do so.
ITEM
VOLTS
WATTS
COST/
HOUR
COST/
DAY
COST/
MONTH
COST/
YEAR
TOTAL
COST
TEMP.
(optional)
1. _______ Watt
Incandescent Bulb
2. _______ Watt
Incandescent Bulb
3. ______ Watt
Fluorescent Bulb
4. ______ Watt
Fluorescent Bulb
5.______Watt LED
6. ______ Mystery
Bulb (guess!!!)
7. Phone Charger
(without phone)
8. Phone Charger
(with phone)
9. Battery Charger
10. Laptop Cart
11. Speakers
12. VCR/DVD Player
Directions: Use the information gathered during your lab work to answer the following questions.
1. The energy is going from the outlet, through the cord and into the light bulb. What changes happen to the energy
while it is in the bulb?
2. A. What is the difference in daily cost between the 60 Watt and 100 Watt incandescent bulbs?
B. What is the relationship between the Wattage of the two bulbs and the daily cost to use them?
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3. A. What is the difference in daily cost between the 60 Watt incandescent bulb and the fluorescent bulb?
B. If the two bulbs are giving off the same amount of light, why do you think there is a difference in energy cost?
4. If the energy is going from the outlet, through the cord and into the hairdryer, what happens to the energy then?
5. If the cost for energy use for a small electric item is $0.20 a day, why doesn’t anything register for hourly use of
that item?
6. Which items use the most energy per day? What could be done to reduce the amount of energy that they use?
7. Thinking ahead to the home portion of this lab, which items do you have that you will test at home? List at least 5
items.
8. Of the items that you have listed for home testing, which ones do you think will use the most energy per day? The
least energy?
9. What can you do at home to reduce the amount of energy needlessly wasted on items that use electricity all of
the time, but are not actually in use by people all of the time?
10. Why didn't I give each student a copy of the directions for using the Kill-A-Watt EZ?
11. What was the mystery bulb, and how do you know?
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KILL-A-WATT EZ LAB – Home Portion
Name:___________________________________________ Date:____________________ Hr_________
In class, you were instructed to work at ten different stations collecting and recording data about power usage and
energy cost for ten different appliances. Using what you have learned about how different appliances use energy
and your Kill-A-Watt meter, your assignment is to find ten appliances in your home to measure. You will use the
table below to record your findings. The instructions for the Kill-A-Watt meter are the same as they were in class,
and are provided on the next page.
ITEM
VOLTS
WATTS
COST/
HOUR
COST/
DAY
COST/
MONTH
COST/
YEAR
TOTAL
COST
Misc.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
1. The phantom load of each device is the power used when the device is turned off but still plugged into the wall
outlet. Phantom loads occur with cell phone chargers, appliances with clocks/lights, televisions, computers, and any
device in sleep mode. Your phantom load can be reduced by unplugging devices when they are not in use. List
several items in your home that have a phantom load.
2. What items on the list from #1 surprised you for their high/low energy usage? Explain your answers!
3. What will you be able to change at your house to save money on your electrical bill? Explain at least 3 changes
with the number of kWh and amount of money each change should save your family per year.
4. What impact will your money-saving choices have on your carbon footprint? If 2 pounds of CO2 are released for
every kWh of electricity used, calculate the annual reduction in CO2 that your changes will make for each of the 3
items listed in question #3 above.
5. If each of the _____ families in our school made the same changes that you have proposed for your home, how
much money could be saved each year, and how much less CO2 could be released from just this part of our
community?
6. Explain what you think about using money savings to motivate people to save energy and reduce their carbon
footprint.
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