ELTR 1223 Survey of Renewable Energy Technology Wind Energy Technology Unit 8 Source: Use Policy This material was developed by Timothy J. Wilhelm, P.E., Kankakee Community College, with funding from the National Science Foundation as part of ATE Grant No. 0802786. All materials in this presentation are designed and intended for educational use, only. They may not be used for any publication or commercial purposes. Source: Author, Editors/Reviewers Author: Timothy J. Wilhelm, P.E., Kankakee Community College Editors/Reviewers / Modifier: Chris Miller Heartland Community College Source: Objectives Students will be able to describe, in very simple terms, at least three different styles of “prime mover” used to convert linear air movement (wind) into rotational shaft movement. Students will be able to briefly describe, in very simple terms, at least two of the basic criteria for properly siting a modern wind turbine. Source: Objectives Students will be able to describe, in very simple terms, how change in wind speed affects the output of a modern wind-driven generator. Students will be able to describe, in very simple terms, three different size-groups of modern wind turbines and their typical applications. Source: Objectives Students will be able to describe, in very simple terms, at least three advantages and three disadvantages, to a local community, relative to the local construction of a commercial wind farm. Source: One of the Earliest Applications of Wind Power Source: http://tonto.eia.doe.gov/energyexplained/images/WINDENERGY1.gif Wind Energy History 5000 BC – Wind-driven sail boats were moving on the Nile River 200 BC – Wind-powered pumps were moving water in China; and, sail-wing windmills (with woven-reed sails) were used in Persia and the Middle East What is a mill? Mill (noun): a. A building equipped with machinery for grinding grain into flour or meal. b. A device or mechanism that grinds grain. Mill (verb): a. To grind, pulverize, or break down into smaller particles. Driving a Mill Source: http://www.tvnet.lv/men/images/upload/04.jpg Horse-Powered vs. Wind-Powered The Term “Mill” Stuck… Wind “Mill” pumps have been used for centuries in the Netherlands. Windmills to Drive Generators Charles Bruch – GE, Cleveland, OH Brush Windmill – 1888 50’ diameter 144 cedar blades 12KW generator Source: http://centros5.pntic.mec.es /ies.victoria.kent/RinconC/Curiosid/rc74/image006.jpg Battery charger Source: http://ecoinventos.files.wordpress.com/2007/05/220237i1.jpg How to Divert Wind Energy Vertical Axis Machines Simplest Least efficient Horizontal Axis Machines Requires “yaw” control – face the wind Can be “upwind” or “downwind” Drag-type blades – applies to both V and H Lift-type airfoils – applies to both V and H Drag vs. Lift Linear wind PUSHES against angled surface and resulting force vectors create torque. Drag vs. Lift Lift-type airfoils use the Bournelli Effect. Source: http://thales.cica.es/rd/Recursos/rd99/ed99-0226-01/liftmovi.gif Single-sided vs. true airfoil Machine Types – VA va HA Source: http://www.redriven.net/skin1/images/wtconfig.gif Vertical vs. Horizontal Axis Vertical axis machines do not care which direction the wind is from. Simple, but inefficient. Unless shrouded, they fight themselves. Vertical vs. Horizontal Axis Vertical requires yaw control and often a mechanical power transmission. More complex. More efficient. Source: http://www.acsaeolica.com/img/productos_torre06.jpg Savonius – Vertical Axis, Drag Source: http://www.reuk.co.uk/Savonius-Wind-Turbines.htm Darius – Vertical Axis, Lift Source: http://www.reuk.co.uk/OtherImages/darrieus-rotor.jpg Midwest Windpumper -- Drag Modern Windgennie -- Lift Source: http://i.treehugger.com/files/airx.jpg Upwind vs Downwind Source: http://thales.cica.es/rd/Recursos/rd99/ed990226-01/sotovento.jpg Source: http://hensonelectric.com/Excel.Color.jpg 2-Blade vs. 3-Blade (vs. 1Blade?) Source: http://3.bp.blogspot.com/_PpVQS40hMA/R5j4vqOuD9I/AAAAAAAAAKA/F3sOpAGsZdc/s320/aerogerador% 2Bmoinho%2Bvento.jpg Wind-Driven Electrical Generators PM Field DC Generators PM Field AC Alternators Smaller machines Battery charging and inversion “Wild” AC Rectified for battery charging and inversion Synchronous Alternators Larger machines Often 3-phase Grid-tied, only Modern Wind Generators Horizontal axis 3-bladed True airfoil Loss-of-load protection Modern electronics High Wind protection Yaw control Pitch control Modern Wind Generators Source: http://www.testek.com/images/diagram.gif High-Wind Yaw Control High winds mechanically force the face of the turbine away from the direct force of the wind. Some machines rotate face sideways. Some machines tilt face back toward the sky. Pitch Control – relies on “Stall” Source: http://thales.cica.es/rd/Recursos/rd99/ed99-0226-01/stallmov.gif PLC Control maintains constant rpm needed for AC grid-tie machines. Source: http://thales.cica.es/rd/Recursos/rd99/ed990226-01/pitchmo.gif Wind Siting – Wind Speed is CRITICAL Power is proportional to the cube of the wind speed…(wind speed)3 ! Wind Turbine Siting – Wind Speed Estimates Source: http://www.seps.sk/zp/fond/2002/vietor/enq2.jpg Wind Turbine Siting – Wind Maps Wind Turbine Siting – Wind Rose Wide wedges gives the relative frequency of each of the 12 wind directions. 2nd wedge tells how much each sector contributes to the average wind speed. Red wedge how much each sector contributes to the energy content of the wind. Source: www.windpower.org Wind Turbine Siting – Terrain Effects Laminar flow vs turbulent flow Roughness and obstacles Laminar flow (straight-line) winds are available aloft. Rule of Thumb: Bottom of turbine’s swept area should be 30’ to 50’ above anything within a 300’ horizontal radius. Power-cubed – wind-speed relationship…taller tower is cheaper than heavier machine with heavier tower. Speed up effect Hill effect Speed up effects Tunnel effect Sizes and Applications Small wind – residential Small wind – commercial 10KW and less 100KW and less Large wind – commercial wind farms, industrial applications Small wind issues Suitable wind resource Sufficient property/space Allowed by zoning Accepted by neighbors Technical ability of the owner to maintain the machine Tower types – monopole, lattice, guyed, tilt-up Tower types Source: http://www.northerntool.com/images/product/images/339987_m ed.gif Commercial wind siting Same as small wind, plus… Sufficient participating land owners Proper zoning ordinance Special Use Permit Application County Planning Commission County Zoning Board of Appeals County Board Special Use Permit Granted Building Permit Application and Approval Commercial Wind issues Shadow Flicker Blade Glimmer Amplitude Modulation Noise Infrasound Disturbance of the natural vista Vibro-Acoustic Disease/Wind Turbine Syndrome TV and Communications Interference Interesting Experiences Future? Maglev Wind Turbine Source: http://www.technogeek.ro/images/turbina_maglev.jpg