September - Vol 70, No 1 - International Technology and ...

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Rural Electrification Authority (REA) installed electric power lines into these areas (Gillis, p.4) Interests in Wind Power America’s interest in and policies toward alternate energy and wind power has been much like a yo-yo. Changes in the supply, demand, and pricing of energy drive energy policy. This can be seen in the invention and innovation of windpower devices throughout history. The Arab Oil Embargo of 1973 resulted in an oil crisis in the early 1970s and brought about a flurry of interest and subsequent grants, research initiatives, and demonstration projects for a variety of energy generation and development that emphasized renewable and replenishable resources. Research projects focused on wind, solar, geothermal, and biofuels such as ethanol. A number of large wind-power projects appeared in the early 1980s. California is noted for its warm and sunny weather, and most notably its prevailing winds that originate over the Pacific Ocean, and became home to a number of wind-power projects. One of the most notable was the Altamont Pass wind farm. The Altamont Pass project attracted three of the earliest wind-farm builders (Gillis, p.58). U.S. Power built the first 100 turbines that had three-legged 60-foot towers with three-blade rotors attached to a generator mounted at the top of the tower. Another builder, Fayette Manufacturing, erected 50 turbines on 40-foot thin tubular towers with blade diameters of 50 feet. U.S. Wind Power’s turbines at Altamont produced about 1.5 million kilowatt-hours of electricity. The wind turbines at Altamont Pass and other wind farms would establish technology trends with their large three-blade rotors on a single steel tower. research projects. These activities will augment the scientific and technical exchanges that already occur between the two Departments. The goal is to facilitate the development of offshore clean energy. Additionally, it is expected that these efforts will create clean energy jobs while expanding the nation’s renewable energy portfolio and easing America’s reliance on fossil fuels. (U.S. Department of Energy) Engineering and Technical Careers There are a variety of professional and skilled-worker jobs available in the wind-energy sector. As new windenergy projects are designed, constructed, and operated, employment opportunities will be realized. Much of the funding for alternative and wind-energy projects comes from federal and state grants and research projects. Jobs in these areas will require people with business skills and knowledge, as well as meteorological and engineering experience, to plan and build projects. Expect to see meteorologists helping engineers identify appropriate sites with suitable geographical and wind Photo Credit: Warren Gretz/NREL By the late 1980s wind farms were generating large quantities of electricity in California. Texas would soon take over the leadership from California in wind-produced electricity, and by the end of 2006 Texas had an installed base of 2,768 megawatts of wind-generated capacity! While the energy of the wind is free, critics often complain that wind energy is not cost-effective without government subsidies (Gillis p.56). Further, environmental groups oppose large-scale wind farms because of the threat to migratory birds, their loud low-pitched sound, and what some consider to be large unsightly structures. Today there is renewed interest in continuing to develop and build wind farms and other alternative energy resources. Recently, the U.S. Department of the Interior and Department of Energy have combined efforts to develop renewable offshore energy resources. The two agencies will exchange information on resources and technologies, conduct stakeholder engagements, and collaborate on Figure 4. Certification test engineer Arlinda Huskey is shown here measuring noise emission from the Advanced Wind Turbines, Inc. AWT-26 wind turbine at the National Wind Turbine Technology Center using a microphone, signal analyzer, and data recorder. 12 • Technology and Engineering Teacher • September 2010
conditions. Engineers design the wind-plant facilities while working with the power utility companies and surrounding communities. A variety of construction worker classifications are needed to construct the wind plant. Mechanical and electrical technicians and technologists are needed to operate and maintain the wind turbines. These technicians are called “windsmiths.” Aside from technical positions in the alternative and wind-energy area, there are business, management and marketing, sales, communications, human services, and personnel positions that offer many professional career opportunities (EERE). Most all of the technical, engineering, and professional careers require math and science skills. Critical-thinking and problem-solving skills such as those gained in science, math, technology, and engineering classes are a significant asset in careers that you may find attractive and rewarding. Technicians and technologists use test equipment to measure and test the efficiency and performance of complex equipment and require math and technical skills to accurately interpret charts and graphs for technical reports (Figure 4). Photo Credit Warren Gretz/NREL Figure 6. Here is an exploded illustration view of the inside of a typical wind turbine. Shown here are the turbine rotor and nacelle and their technological systems. A mechanical system converts the kinetic energy of the wind into mechanical energy, and the mechanical energy is converted into electrical energy that is transported and used by the consumer (Courtesy of EERE). Specific careers in technical and nontechnical administrative and professional support fields can be found in the Dictionary of Occupational Titles (www.occupationalinfo. org/) and “ONet” Online Occupational Information Network (www.occupationalinfo.org/onet/). How Wind Generators Work Windmills and wind turbines depend on the motion of air currents or wind to turn some type of propeller or rotor to convert the wind energy into mechanical energy. It is this principle that is common to windmills of the past and present-day wind turbines. Today we call windmills wind turbines, as they are more sophisticated in design and construction. Wind turbines generally are classified into two major categories: horizontal-axis and vertical-axis machines. The most common design is the horizontal design as shown in Figure 5. These are three-blade turbines that are designed to face the oncoming wind. Figure 5. Wind turbine construction workers and engineers are hoisting a Westinghouse 600 kW wind turbine rotor and nacelle assembly on top of a steel tower at the NREL National Wind Technology Center (NWTC), where the turbine will be modified for use as a test bed for component testing. When we look inside a wind turbine nacelle or housing, we can see a number of technological systems such as shown in Figure 6. These include a mechanical system of gears and shafts to modify the low speed of the rotor through a gear box to increase the generator shaft speed. The rotor is part of this mechanical system that converts the kinetic energy of the wind into mechanical energy. The wind moving across the blades of the rotor creates a 13 • Technology and Engineering Teacher • September 2010
Page 1 and 2: DESIGN SQUAD (NEW!) • SUPER MILEA
Page 4 and 5: Contents september • VOL. 70 •
Page 6 and 7: STEM News Election Candidates The 2
Page 8 and 9: STEM Calendar October 4-7, 2010 The
Page 10 and 11: The Road to Minneapolis Leads To: A
Page 12 and 13: This year, in addition to handing o
Page 14 and 15: Significant measures are undertaken
Page 18 and 19: “lift” and therefore rotation o
Page 20 and 21: Classroom Challenge Rooftop Garden
Page 22 and 23: Any good design has plenty of illus
Page 24 and 25: More recently, Mitts (2008) broke n
Page 26 and 27: events (Mitts, 2008). Before tabula
Page 28 and 29: Middle School Event Event Type 246
Page 30 and 31: References Cummings, J. (1998). For
Page 32 and 33: Brainstorm and Design Prompt your s
Page 34 and 35: Advancing STEM Education: A 2020 Vi
Page 36 and 37: One of the most significant challen
Page 38 and 39: Phase Timeline Goal Initiating the
Page 40 and 41: 2010 Super Mileage Challenge The 20
Page 42 and 43: Q: What Do YOU Need to Succeed in T
Page 44: Manufacturing is Cool! Through crea

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