My Daily Energy Use. Objectives: Target grades: AK GLEs:

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1 AK Target grades: 9-12 AK GLEs: Science [9/10/11] SA1.1 [9] SA2.1 [11] SA3.1 [9] SE2.1 Reading [9/10] Math [9] N-3 [9] E&C-3 [9/10] S&P-1 [9/10] PS-5 Set up time: 45 minutes Class time: Two or three class periods Overview: Students will learn how to conduct an energy audit of their house and calculate a monthly energy bill. Projected energy savings will be assessed from various energy efficiency and conservation measures. Objectives: Students will determine their household energy consumption, understand how appliances and devices use varying amounts of electricity, and identify ways to conserve and use energy more efficiently. Materials: Personal energy consumption student spreadsheet file Computers with Internet access and Microsoft Excel Background: In 2008, the U.S. Department of Energy reported that the average American household uses 920 kilowatt-hours (kwh) of electricity a month. Homes and commercial buildings consume 71% of the electricity in the United States and this number is expected to rise to 75% by 2025 ( Existing residential buildings represent an extremely large source of potential energy savings. According to the Alaska Energy Authority s 2012 End Use Study, residential electricity consumption is quite significant. Major appliances such as refrigerators, freezers, washers, and dryers consume 24% of the electrical energy in households in the Railbelt and Southeast Alaska and consume 35% of the electrical energy in households in Bethel. Appliances such as TVs and microwaves continue to draw power even when switched off. Eliminating these phantom loads by unplugging them and turning off appliances like lights, computers, and TVs when not in use are all ways to realize energy savings ( buildings/res_building_design.html). Most of us do not think about how much electricity we actually use. We flip a switch and the lights turn on, or we press a button and the TV or computer turns on. However, every flip of a switch or press of a button means we are (1) using electricity and (2) spending money. Understanding how much energy these appliances use and how much they cost to run each day is valuable and can help facilitate more responsible behavior through conserving energy or using more efficient appliances. This lesson will allow students to become more aware of

2 2 their everyday energy use and the associated costs. Energy Conservation: Energy conservation is a behavior change that results in not using energy at a time when one normally might. For example, riding a bike instead of driving a car, unplugging computers and other electronics at night or when not in use, or turning off the lights when you leave a room. Energy Efficiency: Energy efficiency is using improved technology that makes an existing use of energy more efficient; i.e., allows us to do more with less. For example, replacing incandescent light bulbs with compact fluorescents (CFLs) or LEDs, adding extra insulation to a house, or using Energy Star appliances that have special power-saving measures installed. Watt: A watt is a basic unit of power which measures electricity. watt = joules per second Kilowatt-hour: In order to determine the amount of energy used over a period of time, we use the measurement of watt-hours. A watt-hour is the amount of electricity for one watt of power for one hour. watt-hours = watts x hours Electric companies measure and charge customers on how much electricity consumers use in kilowatt-hours, or kwh. kilowatt = 1000 watts A kilowatt-hour refers to using 1000 watts, or 1 kilowatt, of electricity over an hour of time. 1 kilowatt-hour (kwh) = 1000 watts x 1 hour = 100 watts x 10 hours Therefore, one 100 watt bulb turned on for 10 hours uses 1 kwh of electricity. Phantom Load: Frequently we use electricity in our homes when we don t even realize it! Also known as standby power, phantom loads are wasted amounts of electricity consumed by an electronic device or appliance while it is turned off or in standby mode. For example, the power that keeps the clock going on your microwave is a phantom load. Even though your TV and DVD player may be turned off, they are operating in standby mode and still using energy. This use of energy costs money too! One easy and cost-effective way to reduce or eliminate phantom loads is to use power strips that you can easily turn off when not using the appliance. This ensures that all of the appliances are not drawing any energy. Methods of Measuring Energy Consumption: There are multiple methods to measure personal, household, or school energy consumption, including using energy bills, Kill-A-Watt meters, and conducting online energy audits. While energy bills allow a homeowner to keep track of how much energy is used from month to month, they do not indicate how much energy specific appliances or devices use. A Kill-A-Watt meter measures the energy used in a given outlet by a given appliance or device. For example, you can plug a refrigerator or computer into a Kill-A-Watt meter (which is, in turn, plugged into a wall socket) and measure the amount of energy that the device uses over an hour, day or a

3 3 week. Kill-A-Watt meters are a great way to closely monitor how much energy individual devices and appliances use. However, if you do not have a Kill-A- Watt meter, there are several online tools for estimating your home s energy consumption based on the total number of household devices and appliances in your home. Knowing How Much Energy You Consume: Gauging your energy use off of your electric utility bill gives you a starting place, or baseline, from which to begin your investigation. Measuring consumption of specific appliances with a Kill-A-Watt meter helps identify energy hogs and lets you know when certain appliances start using energy inefficiently. From this baseline you can begin to identify areas and appliances in your home where you can apply conservation and efficiency measures in order to save energy and money. Knowing your energy consumption level can help you be aware of your personal emissions and the impacts those have on the environment. Vocabulary List: consumption - using a resource. efficiency - the ratio of the useful output of a device compared to the energy supplied to it. This can be used when comparing different types of light bulbs. Since an incandescent light bulb requires watts and a similar LED light bulb can produce the same amount of light using a fraction of the number of watts, the LED light bulb is more efficient than the incandescent since it can do the same amount of work with less energy. Alternatively, a diesel generator is able to convert roughly 30-40% of the energy in a gallon of diesel into electricity (with the rest of the energy released as heat), so the generator s efficiency for producing electricity is ~30-40%. energy audit - an evaluation of energy consumption in a home, business, or public building to determine how energy can be conserved or used more efficiently. kilowatt-hour (kwh) - a unit used to measure energy. A kilowatt-hour is the amount of energy used if you use 1000 watts for one hour and is equivalent to 3.6 million joules or 3,412 BTUs. phantom load - electricity consumed by an electronic device or appliance while it is turned off or in standby mode. This includes electricity used to power a clock on a microwave or a small light indicating that a computer is sleeping. Gear Up: Ask students to explain a kilowatt-hour. Next, ask students why it is important to know and understand personal and household energy habits. Guide the conversation based on the background information. Activity: Have students conduct an energy audit of their home by having each student

4 4 use the Personal Energy Consumption Worksheet to list all of the devices and appliances in his or her house that use electricity. Once the students have listed the appliances and devices, visit html. Here they will enter each item and the frequency that it is used each day into the electric cost calculator. The student will receive the average kwh/ month that each item uses and can enter it into the worksheet. The worksheet will automatically total the watt hours for the month and will calculate their electric bill based on the rate of $.20 per kilowatt hour. Adjust the rate based on your local electric rate. Once students have filled out the worksheet, have them answer the following questions. 1. Which of your devices uses the most power? 2. The spreadsheet will multiply your final total number (F53) by 30 (days in a month) and then by.20 (20 cents/kwh) to give you your power bill. What does the spreadsheet calculate? 3. How might you conserve energy or use energy more efficiently? 4. What have you learned about your personal consumption of energy that surprised you? Extension: 1. If you have access to a Kill-A-Watt meter, have the students identify what they think are the five most significant energy hogs at the school. Plug the Kill- A-Watt meter into each device for a day and at the end of the week, calculate how much energy just those five devices/appliances use. If possible, get the electric bill for your school and see how it compares to a home energy bill. 2. You can also have the students conduct an energy audit of the classroom using the Kill-A-Watt meter. Have the students discuss ways that the school and individual classrooms can conserve energy and be more energy efficient. 3. Since nearly all items that consume electricity have a sticker, label, or print on them somewhere that lists either the number of watts or the voltage and current, have the students read appliance labels rather than get the numbers from the suggested website, and then the students can do the calculations themselves. Additional Resources: US Department of Energy This website gives a guide to saving energy through smart choices in building design and remodeling, and the purchase and use of appliances and electronics, lighting, insulation and air sealing materials, heating and cooling systems and landscaping.

5 5 US Department of Energy Database of State Incentives for Renewables and Efficiency This website provides links to other websites related to financial incentives and policies regarding renewable energy and energy efficiency practices. =0&srp=1&state=AK The REEL in Alaska Roadmap Created by Natural Capitalism Solutions, this website demonstrates how Alaskans in the Railbelt region can meet their real electricity needs, with up to 50% greater efficiency in the use of electricity from centralized generation, by 2025 (as compared to the year 2000). port Alaska Grade Level Expectations addressed: Science Performance Standards [9] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring, and communicating. [9] SA2.1 formulating conclusions that are logical and supported by evidence. [9] SE2.1 questioning, researching, modeling, simulating, and testing a solution to a problem. [10] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, analyzing data, developing models, inferring, and communicating. [11] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, analyzing data, developing models, inferring, and communicating. [11] SA3.1 conducting research and communicating results to solve a problem (e.g., fish and game management, building permits, mineral rights, land use policies). Reading Performance Standards [9] Connecting information by making inferences and/or drawing conclusions within a text (e.g., why is the information in the chart included), across texts or other summarized information. [10] Connecting information by making inferences and/or drawing conclusions within a text (e.g., why is the information in the chart included), across texts or other summarized information. Math Performance Standards [9] N-3 [using models, explanations, number lines, real-life situations L] describing or illustrating the effects of arithmetic operations on real numbers (M1.4.3).

6 6 [9] E&C-3 multiplying or dividing rational numbers including integers with whole number exponents (M3.4.3.) [9] S&P-1 [designing, collecting L], organizing, displaying, or explaining the classification of data in real-world problems (e.g., science or humanities, peers, community, or careers) using information from tables or graphs that display two sets of data [or with technology L] (M6.4.1). [9] PS-5 using real-world contexts such as science, humanities, peers, community, careers, and national issues (M & M10.4.2). [10] S&P-1 [designing, collecting L], organizing, displaying, or explaining the classification of data in real-world problems (e.g., science or humanities, peers, community, or careers), using information from tables or graphs that display two or more sets of data [or with technology L] (M6.4.1). [10] PS-5 using real-world contexts such as global issues and careers (M & M10.4.2). Alaska General Content Standard addressed: Skills for a Healthy Lifestyle SHL. D 1 & 2 1) make responsible decisions as a member of a family or community; 2) take responsible actions to create safe and healthy environments. Technology T. A 1-3 1) use a computer to enter and retrieve information; 2) use technological tools for learning, communications, and productivity; 3) use local and worldwide networks. T. B 1 & 2 1) identify and locate information sources using technology; 2) choose sources of information from a variety of media. T. C 1 & 2 1) use technology to observe, analyze, interpret, and draw conclusions; 2) solve problems both individually and with others. T. E 6-8 6) evaluate ways that technology impacts culture and the environment; 7) integrate the use of technology into daily living; and 8) recognize the implications of emerging technologies. Cultural Standards CS B 2-4 2) make effective use of the knowledge, skills, and ways of knowing from their own cultural traditions to learn about the larger world in which they live; 3) make appropriate choices regarding the long-term consequences of

7 7 their actions; and 4) identify appropriate forms of technology and anticipate the consequences of their use for improving the quality of life in the community. Acknowledgment: This material is based upon work supported by the Department of Energy under Award Number DE-EE Disclaimer: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.