A. Title of Lesson: Quantification of Appliance Electricity Consumption at Home B. Author: Geoffrey Kavulya C. Audience: 5th -8th grade science students D. Timeframe for entire lesson: 3 classroom sessions of 55 minutes E. Abstract This lesson will provide students with an opportunity to understand energy and electricity basics such as energy conservation, energy metrics and ways of minimizing electricity waste around the house. On the first day students will learn about various electrical appliances and their associated electricity consumption. Students will learn how to read and interpret appliance energy labels to extract information such as appliance wattage. Students will have access to a variety of electrical appliances such as laptop, toaster, microwave, fridge, desktop computer, coffee maker, paper punch, kettle, projector, desk lamp and variety of bulbs. On the second day students will learn the differences between plug loads and phantom (vampire) loads. These differences are necessary to understand the level of electricity waste associated with human activities such not unplugging appliances when not in use. Moreover, students will brainstorm on ways to save electricity around the house or in school. Students will also carry out a survey of electrical appliances found around the house and in the classroom. On the third day students, will learn how to carry out energy audit surveys. Energy audit will include measuring electricity using energy meters such as commercially available Kill-a-Watt meters. After collecting electricity data from actual appliances, student will engage in data analysis activities. After analysis, students will graph appliance consumption by the various appliances (both ON and OFF conditions). Students will identify big electricity consumers and sources of high vampire loads. F. Key Vocabulary • Energy - The ability to do work. Electrical energy is measured in kilowatt-hours (kWh), while heat energy is usually measured in British thermal units (Btu) • • • • • A watt is a measure of electrical energy consumed. Voltage is a measure of electrical potential or pressure. Amps are a measure of current, or the flow of electrons. Amps * volts = watts Electricity - A form of energy characterized by the presence and motion of elementary charged particles generated by friction, induction, or chemical change. Energy Efficiency – Using less energy to provide service such as lighting, heating etc Energy Conservation- reducing energy by minimizing energy
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Appliance - A piece of equipment, commonly powered by electricity, used to perform a particular energy-driven function. Examples Computers, printers, copiers, TV sets, Refrigerator Electrical power is the maximum power drawn by an appliance. We use current, voltage and resistance to calculate electrical power. Phantom/Vampire loads- Electricity consumed by an electrical appliance when not in use. Plug loads- these are electrical devices or appliances that use/draw power through electrical outlet. Analogy: Think of circulatory system. Voltage can be equated to blood pressure, current can be equated to flow rate and resistance is like vein size.
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G. Learning Objectives 1. Students will learn about electricity consumption of common appliances found at home. 2. Students will learn fundamental concepts of plug loads, phantom loads and metrics used to quantify electricity consumption. 3. Students will learn to conduct energy audit survey and brainstorm ways to save energy (energy conservation) 4. Students will learn how collect, statistically analyze data, construct graphs and interpret results. H. Sources 1. Phantom Loads: http://www.youtube.com/watch?v=zgZfry82LC4 (Video) 2. EnergyHog.org. No and low cost tips to save energy and money. Retrieved January 1, 2013 from http://www.energyhog.org/pdf/No-Cost_Low-Cost_Ultimate-Checklist.pdf 3. Stanford University School of Earth Sciences, Earth Systems Program. Sustainable Choices Card. Retrieved on February 2, 2013 from http://sustainablechoices.stanford.edu/ 4. Energy Information Administration www.eia.gov/kids 5. "U.S. Census Bureau – World POPClock Projection". July 2012–July 2013 data. http://www.census.gov/population/popclockworld.html 6. Electrical appliances • http://www.ase.org/section/topic/appliances/ • http://www.eere.energy.gov/consumer/your_home/appliances/index.cfm/mytopic=10020 7. Motavalli, Jim. "Hey, Dude, Where's My Phantom Load? | Yahoo! Green." Web log post. News, Blogs, and Tools for Living Green | Yahoo! Green. YAHOO! Green. http://green.yahoo.com/blog/daily_green_driving/23/hey-dude-where-s-myphantom-load.html. 8. "Tree Hugger TV: Vampire Power : Video : Planet Green." Planet Green: Sustainable Living,
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Energy Conservation, Earth Day. http://planetgreen.discovery.com/videos/tree-hugger-tvvampire-power.html 9. http://www.ocf.berkeley.edu/~recycle/ssec/download/Phantom%20Load.pdf I. Attachments 1. 2. 3. 4. A presentation of electricity consumption and appliance labels Plug loads and phantom loads video Plug load spreadsheet Floor layout plans with different appliances
J. Standards Mathematics: Statistics, and Data Analysis. • Compute the range, mean, median, and mode of data sets. Physical Science • Transfer of electrical energy when heat, light, sound and chemical changes occur. K. Class Activities Day 1: Auditing electrical appliances and Interpreting Electricity Bills Introduction On the first day, students will be introduced to various kinds of electrical appliances (devices), which require electricity to do work. Students will identify the different kinds of electrical appliances found around the house and classroom such as computers, printers, refrigerators, lights, projectors, telephones, ranges and stoves, vending machines, fans etc., which have ON/OFF switch. These kinds of appliances consume electricity as long as they are connected to an electrical outlet. It is important to determine electricity consumed by different appliances in order to get a sense of the cost of operating them. Electricity is responsible for generating greenhouse gas emissions, which affect our environment. Students will respond to a couple of research questions related to electricity consumption. To save energy, it is important to turn off electrical appliances when not in use and if possible unplug appliances from electrical outlets. Research Questions a) How much electricity do electrical appliances found at home consume? b) How can we estimate electricity consumption of an appliance?
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Day 2: Measuring Plug Loads Lab On the second day, students will be introduced into the concepts of plug loads, phantom loads and ways to save energy. Additionally, students will carry out a survey of typical electrical appliances found around the house and in the classroom. Pre-lab Questions 1. What is energy? List some sources of energy
2. What is electricity? List common electrical appliances found around our homes
3. What is energy conservation? List some ways that we can use to conserve energy
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4.
Carry out a survey of appliances found in your home and classroom
HOME Appliance Name CLASSROOM Appliance Name
Quantity
Quantity
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
5. Create a list of appliances that you require in everyday activities and the ones you can eliminate from your home to save energy. Day 3: Measuring Phantom Loads Lab On the third day, students will use energy meters (such as Kill a Watt meters) to measure electricity of common electrical appliances. Moreover, students will be introduced electricity calculation formulae. Hook There have been several movies on vampires in the recent past. Introduce the subject of vampires to start a conversation on phantom loads. Have students illustrate things associated with vampires. Is there a relationship between the concept of vampires and energy usage? Show the students a video on Vampire/Phantom loads. Discuss the video and ask students to describe a phantom load and why it is important to eliminate phantom loads. Finally, have students write a short description of phantom loads.
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a) How to determine wattage, voltage, current and electricity cost Wattage = ������������������������������������������ ������ ������������������������������������������ Current = Voltage = ������������������������������������������ ������������������������������������������ ������������������������������������������ ������������������������������������������
1000 Watts = 1 ������������������������������������������������ 1 Kilowatt costs 18 ������������������������������ ������������������ ℎ������������������
b) Daily Appliance electricity consumption
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Materials • A log of common appliances found around our homes and school • Energy audit (data) sheet • Internet access • Electricity measuring meter such as Kill-A-Watt (1 per group) • A set of electrical appliances such as laptop, toaster, microwave, fridge, desktop computer, coffee maker, paper punch, kettle, projector, desk lamp and bulbs of different wattage etc. • Video on phantom loads • Graphing material Procedure 1) 2) 3) 4) 5) 6) 7) 8) Plug meter into extension cord. Plug extension cord into wall outlet. Plug in one electrical appliance at a time Push voltage button and record value on data chart. Push the current (amp) and watt buttons, recording the values each time. Turn off the appliances and repeat for voltage, current and wattage Test and record information for all remaining appliances. Plug lamp into meter. a. Fasten the 60W bulb onto the lamp
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b. Push the Kilowatt- hour button (the purple button). c. Observe the readings and record in the chart. d. Repeat for the other bulbs
Pre-lab Questions 1. What kinds of things are associated with vampires? 2. Why might this be related to energy usage? 3. Why is it important to find and eliminate vampire loads? 4. What types of appliances do not use electricity when they are turned off? 5. Which appliances use electricity when off, but plugged in or in standby mode? 6. Look at the Vampire Watts value for each of these appliances and compare it to the operating watts. How do you think this affects the amount of energy our classroom is using?
7. What is the total wattage drawn by the appliances under the following conditions a. b. c. d. 8 hours of operation per day 12 hours of operation per day 24 hours of operation per day 1 month of operation (1 month = 720 hours)
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Fill in the chart below. The copier has been completed as an example.
APPLIANCE Quantity Typical use Wattage Hours/Day COST Days/Year Annual cost
Copier 1 Printer Computer monitor Desktop computer Coffee maker Pencil sharpener Kettle Microwave Fans Vacuum cleaner Radio Cellphone
8
100
$0.10kWh 10
Data Analysis and Results 1. Which appliances consume the most electricity and which consume the least? 2. Arrange appliance consumption in an ascending order
3. What is the average electricity draw in watts for all the appliances tested?
4. Plot a graph appliances and electricity consumption in watts
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