Rivers were an essential part of the expedition. The flow of a river creates massive energy. The story of hydropower in America is the story of taking this massive natural force of energy and harnessing it to create electrical power for millions of people. Join us from Garrison Dam in North Dakota and learn how dams are built, how their technology creates electricity, and how that electricity gets from the dam to the light switch in your home. Join experts from the United States Army Corps of Engineers as we investigate these scientific questions.
Contents of the Broadcast:
1. Opening to 4:05--Introduction, welcome, information on today's location, orientation to today's topic, introduction of guest experts
2. 4:05 to 14:28--The first essential question we deal with in this program is "What is electricity?" To answer this question and learn basic information about different types of electricity, we are joined by students from Queen of All Saints
Elementary School in St. Louis, Missouri. Their presentations deal with three topics: 1) how electrons create electricity; 2) how static electricity is created; and 3) how direct current electricity is created. Sample activities used in the student presentations on static and direct current electricity are also included on the learning activities page for this program. The students also answer questions on these topics asked by the Internet and videoconference audiences.
3. 14:28 to 29:42--In this segment, we begin to look at our second essential question for the program: "How is hydropower created?" To begin to answer that question, this segment focuses on how a dam is constructed. We are joined by Bob Krumwiedge, Chief Operations Officer at Garrison Dam. He describes his job and the control room at the dam and takes us through video footage showing the construction of Garrison Dam. He also answers student questions dealing with these topics. They include: 1) How many people work at the dam; 2) What education/training is needed to work at the dam; 3) How many gallons of water pass through the dam daily?; 4) How big are the turbines?; 5) How many people constructed the dam?: 6) What kind of jobs were needed to construct the dam?; and 7) How were people living in the area affected by the construction of Garrison Dam?
4. 29:42 to 53:55—We continue to answer our second essential question as we now concentrate on the process of hydropower generation itself. We begin with another presentation from students at Queen of All Saints Elementary dealing with how an alternating current is created. The activity they demonstrate is included on the learning activities page of this web exhibit. Next, Chief Krumweide takes students on a tour of the plant. We begin with a cross-sectional view of a hydroelectric station and then tour the dam itself. Students learn how hydropower works as we move from the lake outside the plant to the intake structure, surge tanks, generator floor, the inside of a generator including its shaft, a turbine, blades, water tube, wicket gates, a turbine in operation, and finally back outside again to the step up transformers. Chief Krumweide also answers student questions including: 1) What major problems has the dam experienced?; 2) What or who is the dam named after?; and 3) How is the magnetic field created in the dam's turbines?
5. 53:55 to 59:35--Next, we look at essential question three for the conference: how does the electricity get from the dam to people's houses? Chief Krumweide describes how voltage is increased as it leaves the dam's power plant, moved along the electrical grid through switchyards, across the nation's electrical grid, and decreased again via more switchyards and transformers on the way to the consumer. Images and student questions are also included.
6. 59:35 to End--We offer closing comments, topics of upcoming webcasts, thanks, and goodbye.
