Smart Grid Tables Exploring the Electrical Infrastructure Grades 9-12 Exploration 1 1. There are three power plants represented on the end of the grid table. List them here. Estimate how much (%) of the total electrical energy generation in Illinois is from each source: Energy Source Percent of total in Illinois Advantages Disadvantages 2. For each source, write two advantages and two disadvantages of that energy source. 3. Research the actual percentages and write the correct numbers in the % column. 4. What energy source is used in Illinois that is not represented on this grid table? 1
Discussion 1 1. In nearly every power plant, something spins a generator to make electricity. In a wind farm, the blades of the wind turbine spin the generator. With natural gas, nuclear, and coal, the fuel is used to turn water into steam which turns a turbine which spins a generator. What energy source is used to generate electricity but has no moving parts? 2. Since all forms of energy have advantages and disadvantages, why are some used more than others? 3. Why is it important to have several different means of generating electricity in Illinois? Exploration 2 1. Check the lower right corner of the Control Panel to be certain that the Smart Grid is disabled. The circle should be red. 2
2. Turn the switch on the Coal Plant and the Renewable Energy Plant all the way to the left (counterclockwise). 3. Turn off the switch on the Nuclear Plant by depressing the left side. 4. What does the analog meter read? 3
None of your power plants are generating electricity. Notice the circle on the lower left of the Control Panel. What message is it communicating? 5. Nuclear power plants are either off or at 100%. Bring the nuclear plant on-line. What happens to the meter? 6. Check the Control Panel. Is the nuclear plant alone capable of bringing the electrical grid up to the proper power level? 7. Start up the Coal Plant by turning the switch slowly one click at a time to the right (clockwise). Watch the analog meter and the lower left corner of the Control Panel. Can the nuclear plant and the coal plant together provide adequate power? 8. Turn up the coal plant all the way. Also, bring the renewable sources on-line. What happens? 9. Adjust the power plants to see what combinations produce the right amount of electricity. Discussion 2 1. What happens if the power companies do not produce enough electricity? 2. What happens if the power companies generate too much electricity? 3. Why might a power company want to use their coal and natural gas plants as little as possible and their renewable plants as much as possible? 4. What happens when the wind does not blow or it is too cloudy (or too dark) to produce solar electricity? 4
Exploration 3 Keep the Smart Grid disabled for now. You should now be generating the correct amount of electricity, but it has to be delivered to your customers. This is done through transmission and distribution lines. 1. Use one wire to connect the Step-Up Substation to the Transmission Tower 1. The wires are in the bin on the back side of the Control Panel. One wire is already hooked up. Connect the red side. 2. Connect all the Transmission towers with the wires. 5
3. Connect Transmission Tower 3 to the Step-Down Substation 4. Connect the brown low-voltage distribution line poles to the apartment building and the farm house. 5. If the power plants are producing the correct amount of electricity, what just happened at the apartment building and the farm house? You may have to adjust the output of your power plants. 6
Discussion 3 1. Look at your analog meter. What does it tell you? 2. Look at the digital Control Panel. What does it tell you? 3. Imagine that a storm breaks the wire that connects the farmhouse to the grid. Disconnect the wire. What happens at the farm house? 4. What happens to the analog and digital meter at the power company headquarters? 5. With the standard grid system, (not Smart Grid) how does the power company know if a customer s power goes out? 6. Reconnect the wire to the farm house. Exploration 4 1. Touch the Smart Grid Enable button on the lower right corner of the Control Panel to switch to the Smart Grid. 7
2. Describe what happens: Disconnect different wires to see how the Smart Grid is different from the standard grid. Discussion 4 1. With the Smart Grid, how does the power company know if there is a problem? 2. How do the electricians find the problem? 3. How can Smart Grid save money and provide better service to the customer? Exploration 5 So far, several of you have all been working together to get the electrical grid hooked up. Now you can split into 3 different groups. Each group should pick a house. 1. Hook up the distribution lines to your house. 8
2. Every customer has an electrical meter on the outside of the building. Go over to the cart and get a standard meter. They are silver with lots of little gears and dials inside the clear cover. 3. Carefully place it in the meter box. It is held with magnets. It must be in the middle. To remove the meter, carefully slide it up and off. Do not just pull. Discussion 5 1. Look at the main Control Panel at the power plants. Your house is listed on their display. Why is there nothing indicated in the Status column? 2. Why must all customers have their own meter? 9
3. Have you seen the electric meter at your house or apartment? Where is it? 4. Why is it VERY IMPORTANT to never touch, try to remove, or otherwise tamper with the electrical meter? Apply It! The power company has now delivered electricity to your house. It is your choice on how to use it. 1. Touch your monitor to wake it up. 2. It should say Standard Meter in the lower left corner of the monitor. 10
3. Be sure all 6 switches mounted on the floor are turned off (no red showing) and that the HVAC is turned all the way to the left (counterclockwise). 4. Go over to the cart and get a plastic tote that contains your appliances. You can probably set it on the table beside the monitor. Please do not use your appliances for other houses. 5. Select a washer, dryer, stove, refrigerator, light, and TV. It does not matter which ones. Put them on the right spots. Magnets will hold them in place when they are set correctly. 11
6. Touch Reset on the monitor. 7. Touch Start on the monitor. Watch what happens. 8. As the time of day progresses, turn on the appliances one at a time. Notice the information provided on the monitor. 9. Don t forget about the HVAC. It is your heating and cooling system and uses electricity like any other appliance. How does the setting of the HVAC affect the amount of energy it uses? Part 1: Appliance Energy Use In this activity you will compare the energy use of two different appliances. Choose any two appliances from the tote. You can use the HVAC as one of your appliances. Appliance #1 1. Install the first appliance and write it s information in the table below 2. Touch RESET 3. Touch START 4. Turn on your team s appliance 5. After 4 hours on the clock, touch STOP 6. Record the data of your appliance from the monitor onto the chart and graph: Appliance Efficiency Watts Watts Used Usage Cost 12
Turn off and swap the appliance out for the second appliance you chose. Appliance #2 1. Touch RESET 2. Touch START 3. Turn on your team s appliance 4. After 4 hours on the clock, touch STOP 5. Record the data of your appliance from the monitor onto the chart: Appliance Efficiency Watts Watts Used Usage Cost Part 1: Discussion 1. Which appliance is more expensive to run based on Usage Cost? 2. Which appliance used more Watts? 3. Describe the difference between the graphs of the two appliances: 4. How much does energy cost per kilowatt hour (Current Cost kwh)? $ 5. Which of the two appliances you tested used more energy, and how do you know? 6. Give an example of an appliance that usually is turned on for a long period of time. 7. Give an example of an appliance that is usually only kept running for a short period of time. 8. How could you use this data to decide which appliances to run for longer or shorter amounts of time during the day? 13
Part 2: Smart Meters In this activity you will learn the difference between standard meters and Smart Meters. You should still have the standard meter installed. Be sure it says Standard Meter on your monitor. 1. Touch RESET 2. Touch START 3. What is the Current Time? AM 4. What is the Electricity Cost? $ /kwh 5. Turn the appliances off and on. Watch the monitor. 6. Touch STOP after a few hours 7. What is the Current Time? AM 8. What is the Electricity Cost? $ /kwh Carefully remove the standard meter from your meter box. It works best if you slide it up and off rather than just pull it. Install the Smart Meter. It should now read Smart Meter on the monitor. Also, check the Control Panel at the power plants. What changed? 14
1. Touch RESET 2. Touch START 3. What is the Current Time? AM 4. What is the Electricity Cost? $ /kwh 5. Turn appliances off and on. Watch the monitor. 6. Record what happens with the price of electricity and the time it changes. Part 2: Discussion Answer the questions and then discuss as a group: 1. What change do you notice on the monitor when you switch the standard meter with the Smart Meter? 2. How would seeing different prices affect when you use appliances? 3. If energy is less expensive at night, why wouldn t you run your appliances at night? 4. Why do you think an energy company would charge less to use energy at some times during the day and charge more at other times? 5. You probably noticed that the price changes a few times throughout the day. The power company calls this Peak and Off Peak. What do these terms mean? 15
Part 3: Energy Efficiency In this activity you will learn about energy efficiency. Pick your appliance, write the data, and watch the clock! 1. Use both of the same type of appliance 2. Install ONE of them. 3. Write down the information in the chart: Appliance Efficiency Watts Watts Used Usage Cost 5. Touch RESET 6. Touch START 7. Copy the EnergyGuide Tag 8. Touch STOP after 4 hours. 9. Write the Watts, Watts Used, and Cost. Turn OFF and REMOVE your appliance. $ 4. Click 1. Install the SECOND appliance 2. Write down the information in the chart: Appliance Efficiency Watts Watts Used Usage Cost 4. Touch RESET 5. Touch START 6. Copy the EnergyGuide Tag 7. Touch STOP after 4 hours. 8. Write the Watts, Watts Used, and Cost. Turn OFF and REMOVE your appliance. $ 3. Click Part 3: Discussion 1. Which of the two appliances is the most expensive to buy? 2. Which one is the least expensive to buy? 16
3. Give two reasons related to energy why you would purchase an appliance that had a more expensive original cost. 1. 2. 4. How could having knowledge about how to read an EnergyGuide tag help you make informed decisions about purchasing appliances? 5. Some of the appliances are High efficiency and some are Low efficiency. What is the difference? Part 4: Percentage of Use In this activity you are going to learn how to calculate percentage of energy use. 1. Choose two different kinds of appliances. The HVAC can be one of your appliances. 2. Install both appliances 3. Touch RESET 4. Touch START 5. Turn on both appliances at the same time 6. Touch STOP after 4 hours on the monitor clock 7. Fill in the data from the monitor. Current Time: AM Electricity Cost: /kwh Appliance Efficiency Watts Watts Used Usage Cost Current Watts in Use: Total Watts Used: Total Cost: W kwh $ 17
Part 4: Discussion 1. Calculate the percentage of the energy that each appliance uses: Formula: (Part / Whole) x 100 = % Appliance 1: Appliance 2: 2. Which appliance used more energy? Explain how you know which appliance used more energy (what is your evidence?): What do you think would cause the one appliance to use more energy than the other? 3. Do you have control over the percentage of energy use of all the appliances in your home? Why or why not? _ 4. Explain why the Electricity Cost per kilowatt hour remained the same, but the Total Cost changed: Turn off and return the appliances to the tote. 18
Part 5: Price Constraints Install the standard meter. Be sure it says Standard Meter on your monitor. Task 1 1. Choose three appliances that you think use the LEAST amount of energy. You may only choose one of each type of appliance (for example, you may not choose two stoves). Use the EnergyGuide tags to find the purchase prices. 2. Install your appliances 3. Touch RESET, START, then turn on all the appliances 4. Touch STOP after 4 hours on the clock. 5. Fill in the data from the monitor on the chart. 6. Turn off the appliances and return them to the tote when finished. Current Time: AM Electricity Cost: /kwh Appliance Purchase Price Watts Watts Used Usage Cost Current Watts in Use: Total Watts Used: Total Cost: W kwh $ Task 2 1. Choose three appliances that you think use the MOST amount of energy. You may only choose one of each type of appliance (for example, you may not choose two stoves). Use the EnergyGuide tags to find the purchase price for each. 2. Plug in your appliances 3. Touch RESET, START, then turn on all the appliances 4. Touch STOP after 4 hours on the clock. 5. Fill in the data from the monitor: 19
Current Time: AM Electricity Cost: /kwh Appliance Purchase Price Watts Watts Used Usage Cost Current Watts in Use: Total Watts Used: Total Cost: W kwh $ Turn off appliances and return them to the tote. Task 3 Install a Smart Meter. Check your monitor and the Power Plant Control Panel to be certain it is hooked up correctly. 1. Use the same three appliances that you chose for Task 1. Decide when each appliance will be used. Using the Smart Meter, run the scenario for 24 hours, turning the appliances on and off consistent with when they are used and for how long each is used. Why did the cumulative cost change when compared to the cost in Task 1? 2. If you did not have enough money to purchase all of the most efficient appliances, how would you decide which appliances to buy? 3. What patterns did you notice in energy usage and specific types of appliances? _ 20
4. What are the factors that the utility company uses to calculate your electric bill? 5. How could you use the information shown on a Smart Meter to lower your energy cost? Clean Up: 1. Turn off all appliances and return them to the tote. 2. Return the tote and both meters to the cart. 3. Disconnect all wires and return them to the bin. 4. Turn off all power plants 5. Be sure Smart Grid is disabled on the Control Panel. 21
Expanding the Concept In 1831 Michael Faraday discovered one of the fundamental principles of electromagnetism. It is called Faraday s Law. His law explains how electricity and magnetism interact, and forms the basis for modern electric motors and generators. Electric generators convert kinetic (motion) energy into electrical energy. Faraday discovered that electrical current can be generated by spinning a coil of wire inside a magnetic field. The magnets are called the Stator, because they are stationary (don t move) and the coil is called the Rotor, because it rotates. Some source of energy has to be used to turn the rotor. Nuclear power, natural gas, and coal all basically do the same thing. They heat water into steam. The high pressure steam turns a turbine which spins the rotor of the generator. With wind power, the wind blows against the turbine blades to spin the rotor. Solar power is completely different. Sunlight strikes the silicon in the solar cell and causes electrons to flow. There are no moving parts in a solar cell. Many years after Faraday made his discoveries, Thomas Edison, Nicola Tesla, George Westinghouse and many other inventors began exploring the use of electricity. They made motors, lights, generators, sound recordings, the telegraph, and many other amazing devices. 22
You may not have heard stories of the battle between Thomas Edison and Nicola Tesla in the late 1880s concerning electrical power. Edison did most of his work with direct current (DC) and was enjoying the profits of his many patents. Telsa developed alternating current (AC). The problem was how to get electricity to the customers. Both men saw that this was going to be hugely profitable. The problem is that DC electricity could not efficiently be transmitted long distances. Edison proposed building lots of small power plants, probably one in every neighborhood. The voltage of AC, however, was easily changed, making long distance transmission possible. Telsa joined with George Westinghouse to form the General Electric Company (now known as GE). Together they built a few large AC power plants and connected them to customers over a large area. If alive today, Nicola Telsa and George Westinghouse would recognize our power grid. It has not changed all that much since they designed it over 100 years ago. Direct current is not dead, however. Although Thomas Edison lost the battle in the late 1800s, automobiles, computers, LEDs, solar cells, and electric cars all operate on DC power. Batteries are all direct current. Also, it is more stable than AC so companies are finding ways to use high voltage direct current (HVDC) to reduce transmission loss. Photo credit: Angelsharum, Wikimedia Commons, CC BY-SA 3.0 Electrical power coming out of the real generator is at a relatively low voltage. Low voltage is not very efficient for transmission over large distances, so the voltage has to be stepped up. 23
Typical high voltage power lines operate between 138,000 and 765,000 volts. When entering into a city, the voltage is typically stepped down to approximately 10,000 volts. In your neighborhood, it is stepped down again to two lines of 120 volts each. That is why most of your appliances are 120 volts and some, like the dryer, furnace, water heater, and oven operate on 240 volts. In many European countries, household voltage is 220 volts. Remember Michael Faraday? Besides describing generators, Faraday s Law can be used to describe transformers. A transformer is used to change voltage in an electrical system. It has two coils of wire that are wrapped around a core, which is typically made of iron. When electricity flows in one coil, it induces electricity to flow in the other. The side that has more turns (loops) of wire has the higher voltage. In this way, voltage can be stepped up for long-distance transmission, and stepped down for safe (well, safer) distribution in neighborhoods. Primary coil (or primary winding ) Secondary coil (or secondary winding ) 1. Design a transformer that will change one voltage to another. Remember, even the smaller of the two coils can still have over 100 feet of wire. 24
2. Label the following diagram: 1. Why must the voltage of the electricity coming out of the power plant be stepped up? 2. In a step up transformer, which side has more wire, the primary coil or the secondary coil? 3. In a step down transformer, which side has more wire, the primary coil or the secondary coil? 4. If the output of a step up transformer has double the input voltage, how would you expect the lengths of wire in the primary and secondary coils to compare? 5. Design a transformer that has an input voltage of 12 volts and an output of 3 volts. Remember, even the smaller coil probably has well over 300 turns of wire. 25