ENERGY OVERVIEW TARA SMITH, BSU

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1 Grade level: 6 th -8th Standards: Taken from the May 2012 Next Generation Science Standards. Time Frame: 4.E Energy (2) 50 minute class periods Math: 6.RP.A.3c Find a percent of a quantity as a rate per 100 (e.g., 30% of a quantity means 30/100 times the quantity); solve problems involving finding the whole, given a part and the percent. 6.RP.A.3d Use ratio reasoning to convert measurement units; manipulate and transform units appropriately when multiplying or dividing quantities a. Construct a simple explanation for the relationship between energy and motion. [ b. Carry out investigations to provide evidence that energy is transferred from place to place by sound, light, heat, electric currents, interacting magnets, and moving or colliding objects. c. Obtain and communicate information for how technology allows humans to concentrate, transport, and store energy for practical use. f. Develop a model using examples to explain differences between renewable and non-renewable sources of energy. 6.NS.A.1 Interpret and compute quotients of fractions, and solve word problems involving division of fractions by fractions, e.g., by using visual fraction models and equations to represent the problem. Science and Engineering Practices: Obtaining, Evaluating, and Communicating Information Compare and synthesize across texts and other reliable media to acquire and generate appropriate scientific and technical information. (c) Disciplinary Core Ideas: ESS3.A: Natural Resources All materials, energy, and fuels that humans use are derived from natural sources, and their use affects the environment in multiple ways. Some resources are renewable overtime, and others are not.(f) Objectives: Students will be able to Explain the difference between power and energy, difference between KE and PE and that energy is converted, not created. Tell the story of how the United States relates, energy-wise, to the world and other industrialized countries. Compare and contrast how several continents use energy from renewable and nonrenewable resources. Explain on the importance of energy in our every day lives and how often transfers of energy happen. 1

2 Background Information: Concepts: ENERGY OVERVIEW TARA SMITH, BSU What is the difference between power and energy? Power is the rate at which work is performed and is measured in Watts (W) or kilowatts (kw) 1 kw is equal to 1000W. Energy is the power (kw) used over a certain time period (hours, h) and can be measured in kwh. For example, if a device uses 1kW (Power) for 1h (time) it consumes 1kWh of energy Electricity is billed by the kwh The difference between Kinetic Energy and Potential Energy: Kinetic energy: Energy available as a result of motion that varies directly in proportion to an object's mass and the square of its velocity. Potential energy: energy that has not yet been used. For example when an object is about to fall, before it falls, it is 100%PE and 0%KE. Half way down, is is 50%KE and 50%PE. At the bottom of its descent (the second before it hits the ground) it is 100%KE and 0% PE. The First Law of Thermodynamics: Energy can be changed from one form to another, but it cannot be created or destroyed. The total amount of energy and matter in the Universe remains constant, merely changing from one form to another. Energy: The capacity for doing work as measured by the capability of doing work (potential energy) or the conversion of this capability to motion (kinetic energy). Energy has several forms, some of which are easily convertible and can be changed to another form useful for work. Most of the world's convertible energy comes from fossil fuels that are burned to produce heat that is then used as a transfer medium to mechanical or other means in order to accomplish tasks. Electrical energy is usually measured in kilowatt hours, while heat energy is usually measured in British thermal units (Btu). 2

3 Measurements: ENERGY OVERVIEW TARA SMITH, BSU Quadrillion: is a measurement of a large amount of energy (10 to the 15 th power BTUS), notation Q. British thermal unit: Notation, BTU. The quantity of heat required to raise the temperature of 1 pound of liquid water by 1 degree Fahrenheit at the temperature at which water has its greatest density (approximately 39 degrees Fahrenheit). Materials: Part 1: Personal Energy Use Provided chart of different forms of energy, power bill example, writing materials. Part 2: Steam Demonstration A votive candle, (1) 20-ounce plastic soda pop bottle, 24 inches of 1/8 inch soft copper tubing (available at most hardware stores) as separate tubing, or as a thermocouple, tube cutter, modeling clay, electrical tape, sharp knife, scissors, nail (any size), and a large tub filled with water. Part3: World Energy Use Activity 1: Continent Consumption Computers and access to the internet Activity 2: Pie Charts Construction paper, Computers and access to the internet Procedure: Part 1: Personal Energy Use Assign the day before: Have the students make a checkmark every time they use energy. This will be left open to their interpretation and will be followed by a discussion at the beginning of class the next day. They will be provided an organized chart of forms of energy and they will put tick marks in which form they used. This is for awareness more than accuracy. On the other side of the page with the graph on it have them investigate their Electric Bill. Have them list three things they found interesting about the bill. It can be something they had questions about, something they know about their bill, etc. In class have an open discussion on how they used energy the day before and what they found on their electric bill. Use these questions to help the students discuss the homework activity. 3

4 How many times did you use energy yesterday? In what way did you use energy? (For example, flipping on the light switch at home, exercised, drove a car, etc.) Were you unsure if an activity used energy? What was the activity? What did you ultimately decide? After you have asked those questions you can ask these questions so that they can make a connection between how energy is used and how it might be generated. What did you find on your Electric Bill? Possible Answers: We are billed in kwh, pay period, cost of a kwh, etc. When you used electricity (or any other energy found in a household) in the house how do you think that form of energy gets to your house? Possible Answer: Most electricity is generated by the burning of fossil fuels. This heats water in order to create steam that will turn a turbine. The turning of the turbine is what creates electricity that goes to our houses, commercial, and industrial buildings. This question will be explored further in the activities so if the students do not understand it fully it will help spark interest in the concepts covered in this lesson. Since the electric utility has no control over when you run your AC or turn on your lights, how do you think they ensure they have power available to everyone whenever they demand it? How do they manage when thousands of people decide to run their ACs or dishwashers or watch TV at the same time? Possible Answer: To account for reliability, utility companies maintain power plants with 15-20% more capacity (total amount of energy it can provide) than is actually needed. There are two main loads of power: base load and peak demand. Base load power is the least amount of electricity needed at any given time, and is always available. It is often sourced by coal, nuclear and hydropower, which often run at full or near capacity. Peak demand occurs when users increase their energy usage at the same time. Utilities account for peak demand through use of additional power plants that run at a fraction of full capacity. These are often more expensive to run, so utility companies charge more for electricity used during peak hours. 1 Part 2: Steam Demonstration 4

5 This activity will be to demonstrate how energy is transformed into electricity. Many of the energy sources we use today generate steam that rotates a turbine, which generates electricity. The teacher will need the following materials: (1) votive candle (1) 20-ounce plastic soda pop bottle 24 inches of 1/8 inch soft copper tubing( available at most hardware stores) as separate tubing, or as a thermocouple Tube cutter Modeling clay Electrical tape Sharp knife Scissors Nail Water Step 1: Use a knife to cut the plastic bottle lengthwise leaving the top and bottom of the bottle intact. Remove the top portion of the bottle. Put electrical tape over the mouth of the bottle to keep water out. The bottle cap will be too heavy so do not use that to keep the water out. Step 2: Use the tube cutter to cut the copper tubing to about 24 inches. If you have a thermocouple, cut off the ends, and pull out the copper wire inside the tubing. Step 3: At the center part of the tubing, bend the tubing two times around a large pen or felt tip marker to form a coil. Step 4: Poke two holes in the back of the plastic bottle with the nail. Put the two ends of copper tubing through the holes, and bend them down so the ends of the tube will be under water. Step 5: Bend the tubing so it rests on the bottom of the bottle, and the coil is just above the candle. Place the candle just below the coil. (the modeling clay can be used to help hold these in place) Step 6: Hold one end of the copper tubing under water, and suck on the other end until the tubing is filled with water. Quickly rest the boat on the water, so the tubing is filled with water, and both ends of tubing are under water. 5

6 Step 7: Light the candle and wait until the tubing is hot enough to boil the water inside the tubing. There are a few videos different steam boats. Here are three examples: Steam Powered Bottle ( Steam Powered Top ( Putt Putt Boat ( F3F6C113F3&feature=results_main) Follow the demonstration with the following discussion questions: 1. What kinds of power plants use steam power? 2. How do they create steam? 3. How is the steam used to generate electricity? This would be a good place to break if you intend to do this lesson in two fifty-minute class periods. Part 3: World Energy Use Activity 1: Continent Consumption Split the students into groups give each group pieces of paper with the continents listed on them. Australia, Antarctica, North America, Central and South America, Africa, Europe, and Asia (or any countries that you want to compare). Set up a grid and have each group rank where they think each continent (highest to lowest) stands as far as how much energy they consume total (not just electricity, total energy including transportation, industry, etc.). This will be measured in Quadrillions (described in the background information). Once they have done this, show them the actual results of how much energy each continent consumes using the information found at If you want to continue into this topic further you can also set up a grid that shows how much energy each continent generates using the information from Activity 2: Pie Charts Now that the students know how much energy each continent consumes, take a deeper 6

7 look at how the world generates that energy and how it is consumed. For this activity use the information from NEED.org s Intermediate Energy Infobook found on the link provided below. (page 7) First, have them consider the following questions 1.What percent of energy is used in each energy sector transportation residential industrial commercial electricity 2. What percent of energy is from? wind solar coal Nuclear Etc. And then go through the following steps. 1. Each group will be given a broken up pie chart. Each piece of the pie chart will represent the percent of each source of energy that is used through out the world. (For example, coal, biomass, natural gas, hydro, etc.) The pieces should be a different color and have the percentage written on them. 2. Explain to the students that each piece represents an unknown energy resource. Give them the list of resources that are a part of the broken up pie chart and have them figure out which resource correlates with which percentage and why. 3. Have the groups compare and contrast what they came up with and then show them the actual result in the form of a larger example of their pie charts. 4. Discussion questions. How did their pie charts compare? Were the students surprised by any of the actual percentages and why? Others questions? 5. Next, assign each group one or two of the resources and give them the larger piece of pie that represented that resource in step Provide the students with the information about their resource from the NEED Intermediate Energy Info book. 7. Have the groups write out what their energy source is used for in percentages on their pieces of pie. 8. Then have them come up with a short explanation of why they think their energy resource is used for that energy sector. (For example, industrial, commercial, 7

8 electricity, residential or transportation) Assessment: Collect their documentation of when they use energy and written facts about their energy bill as well as the pie chart explanations from each group. Assign each group a continent to research further. This could be in any format you choose, for example, science journal, presentation, or paper. When they are researching they should be looking for the following topics 1. What is the main resource their continent uses to generate energy? 2. How much energy does it generate? 3. If that type is used primarily for electricity, how is it converted into electricity? The International Energy Agency ( is a great resource if you want to see statistics on energy production and consumption in different energy sectors (industrial, residential, etc.) NEED.org s Learning and Conserving Guide ( (page 2, 3)) is also a helpful resource. There are several good examples of how each resource (renewable and nonrenewable) is used to generate electricity on youtube.com, other information can be found on eia.gov, and need.org. Additional Content: References: Activities from: 1. The NEED Project. Electricity. Secondary Energy Infobook The NEED Project. Energy Around the World Teacher s Guide The NEED Project. Introduction to Energy.Intermediate Energy Infobook

9 Learning and Conserving Guide Citation 4. Make a Steam Boat Xcel Energy Inc. Background Definitions from: eia.gov 9