Presentation on theme: "R.E. Generators: Hydropower Prime Movers and Others"— Presentation transcript:
1 R.E. Generators: Hydropower Prime Movers and Others Unit 9aSource:
2 Use PolicyThis material was developed by Timothy J. Wilhelm, P.E., Kankakee Community College, with funding from the National Science Foundation as part of ATE Grant NoAll materials in this presentation are designed and intended for educational use, only. They may not be used for any publication or commercial purposes.Source:
3 Author, Editors/Reviewers Author: Timothy J. Wilhelm, P.E., Kankakee Community CollegeEditors/Reviewers / Modifiers:Chris Miller Heartland Community CollegeSource:
4 ObjectivesStudents will be able to describe, in very simple terms, the so-called hydrologic cycle, and its relationship to hydropower technology.Students will be able to name a “kinetic” type of water turbine, and briefly describe, in very simple terms, how it operates.Students will be able to name a “water-head” type of water turbine, and briefly describe, in very simple terms, how it operates.Source:
5 ObjectivesStudents will be able to mathematically convert feet of water head into pounds-per-square-inch of pressureStudents will be able to describe, in very simple terms, at least one method of extracting energy from the ocean.Source:
7 Hydropower HistoryHydropower used by the Greeks to turn water wheels for grinding wheat into flour, more than 2,000 years ago.Mid-1770s -- French hydraulic and military engineer Bernard Forest de Bélidor wrote Architecture Hydraulique, a four-volume work describing vertical- and horizontal-axis machines.
26 Hydropower Fundamentals Kinetic-type primer movers“Water Wheels”Extract energy from stream-flowHead or Pressure-type Prime MoversHigh (inlet) Elevation – Low (discharge) Elevation = “Head”PSI(pressure) = Feet of Water (head) X 0.433“A pint’s a pound the world around.”1 Ft3 = 7.48 gallons; 1 gallon = 8.34 pounds8.34 lbs/gal x 7.48 gal/ft3 x 1 ft2 / 144 in2 = 0.433
28 Hydro Prime Mover Types: Head-type Turbines Low-Head and High-Flow“Reaction Turbines”Kinetic turbines (water wheels, and other flow converters)Propeller turbinesFrancis turbines (like a squirrel-cage centrifugal turbine)High-Head and Low-Flow“Impulse Turbines”Pelton TurbinesCross-flow Turbines
40 Hydro Plant Sizes Large Hydropower Although definitions vary, DOE defines large hydropower as a capacity of more than 30 MW.Small HydropowerAlthough definitions vary, DOE defines small hydropower as a capacity of 100 KW to 30 MW.Micro HydropowerA micro hydropower plant has a capacity of up to 100 kilowatts. A small or micro-hydroelectric power system can produce enough electricity for a home, farm, ranch, or small village.
47 Ocean EnergyThe tidal forces and thermal storage of the ocean provide a major energy sourceWave action adds to the extractable surface energyMajor ocean currents (like the Gulf Stream) may be exploited to extract energy with rotorsOcean energy is even more treacherous than wind energy. The principle is similar, but the increased density of water over air means a higher potential for destruction.Source:
48 Ocean Energy: Tidal Energy Tides are produced by gravitational forces of the moon and sun and the Earth’s rotationExisting and possible sites:France: La Rance river estuary 240 MW stationEngland: Severn RiverCanada: Passamaquoddy in the Bay of Fundy (1935 attempt failed)California: high potential along the northern coastEnvironmental, economic, and esthetic aspects have delayed implementation
53 Ocean Energy: Wave Energy Salter “ducks” rock up and down as the wave passes beneath it. This oscillating mechanical energy is converted to electrical energyA Wavegen, wave-driven, air compressor or oscillating water column (OWC) spins a two-way Wells turbine to produce electricityThe Salter duck concept has fallen into disfavor due to the difficulties in maintenance. Operation is subject to large storms that may destroy the system.
55 Ocean Energy: OTEC (Ocean Thermal Electric Conversion) OTEC requires some 40°F temperature difference between the surface and deep waters to extract energyOpen-cycle plants vaporize warm water and condense it using the cold sea water, yielding potable water and electricity from turbines-driven alternatorsClosed-cycle units evaporate ammonia at 78°F to drive a turbine and an alternatorYears ago, an OTEC was tested off Port Canaveral without great success. The system works best along a seamount.