1. An Introduction to Wind Energy Frank R. Leslie, B. S. E. E., M. S. Space Technology 1/19/2002, Rev. 1.0 f.leslie@ieee.org; (321) 768-6629

2. Overview zRenewable energy is sustainable indefinitely, unlike long-stored energy from fossil fuels zRenewable energy from wind, solar, and hydroelectric power emits no pollution or carbon dioxide (although the building of the components does) zBiomass combustion is also renewable, but emits CO2 and pollutants zNuclear energy is not renewable, but sometimes is treated as though it were because of the long depletion period zSustainable energy comes from the sun or from tidal forces of the moon and sun Revised 020115

3. Energy considerations for 2050 zFossil-fuel energy will deplete in the future; took millions of years to create that much fuel zUS oil production peaked about 1974; world energy will peak about 2004-9 or so zRenewable energy will eventually become mandatory, and our lifestyles may change zTransition to renewable energy must occur well before a crisis occurs Revised 020115

4. The eventual decline of fossil fuels zMillions of years of incoming solar energy were captured in the form of coal, oil, and natural gas; current usage thus exceeds the rate of original production zCoal may last 250 years; estimates vary greatly; not as useful for transportation due to thermal losses in converting to convenient liquid “synfuel” zWe can conserve energy by reducing loads and through increased efficiency in generating, transmitting, and using energy zEfficiency and conservation will delay an energy crisis, but will not prevent it Revised 020115

5. The Hubbert Curve predicts fossil fuel decline zDr. M. King Hubbert, geophysicist, published his prediction that the US oil peak would be reached in 1970. Later, others predicted the World oil peak would occur in the first decade of the 21st Century. zPast the production peak, oil prices will increase as extraction becomes more difficult and the price is bid up. www.hubbertpeak.com/midpoint.htm Revised 020115

6. Where does our local electricity come from? zOur local utility, FPL, lists these for the 12 months ended May 2001: yPetroleum, 40% yNuclear, 25.5% yNatural Gas, 20% yPurchased Power (various sources), 7.5% yCoal, 7% zAny renewables are in the Purchased Power category zWill we “export our pollution” to other states as California does? Cape Canaveral Plant, photo by F. Leslie, 2001 Revised 020115

7. Solar Energy: Thermal zLow-temperature extraction of heat from ground; ~70° F to 80° F zWater heating for home and business; ~90° F to 120° F zHigh-temperature process-heating water for industry; ~200° F to 400° F zSolar thermal power plants; ~1000° F From www.energy.ca.gov/education/story/story-images/solar.jpeg Arizona has clearer skies than Florida. Ref.: Innovative Power Systems Revised 020115

8. Wind Energy zWind energy results from uneven heating of the atmosphere zWind resources vary greatly worldwide, even within a few miles zPower is proportional to the wind speed cubed Ref.: www.freefoto.com/pictures/general/ windfarm/index.asp?i=2 Revised 020115

9. Wind Energy in Practice zFavorable California tax incentives resulted in major U.S. wind farms yAltamonte Pass yTehachapi ySan Gorgonio Pass zOther turbines are located in Dakotas, Iowa, Texas, Minnesota, Wyoming, Iowa, Vermont, etc. zEarly Twentieth Century saw wind-driven water-pumps commonly used in rural America, but the spread of electricity lines in 1930s (REA) caused their decline www.nrel.gov/wind/usmaps.html Revised 020115

10. Wind Energy is best suited to the Great Plains States zCoastal Florida has Class 2 wind energy (160 to 240 W/m^2) per the PNNL Wind Energy Atlas ― sufficient to investigate but marginal for major wind energy systems zHigh average wind speeds in the Rocky Mountain Region (300 to 1000 W/m^2) and the Great Plains States (200 to 250 W/m^2) Revised 020115

11. Florida has marginal wind energy zThese wind energy maps are available for each state and for the World zCoastal Florida is Class 2 with seabreeze and storm front passages zSummer ground heating results in ~10 mph seabreezes and storms zWinter is calmer, with frontal storm passages averaging every four days From the PNNL Wind Energy Atlas Revised 020115

12. A sample day’s seabreeze wind profile from the FSEC MET system in Cocoa, FL Ref.: FSEC Effective wind is from 9 a.m. to ~5 p.m. Revised 020115

13. Predominant wind energy direction determines the site selected zThe energy rose is the cube of the wind speed (flower-like) rose zIn Palm Bay, Florida, this wind data sample shows the main wind direction at 150 degrees azimuth zSeveral years of data are averaged to get a useful sample; 30 years desirable zIn obstructed areas, the site selection is critical to obtain the maximum wind energy N S Revised 020115

14. Energy is proportional to wind speed cubed zRecall that the average wind power is based upon the average of the speed cubed for each occurrence zThe wind energy varies from trivial to disastrous! zPrecautions are needed to protect the turbine Ref.: Bergey Revised 020115 Turbines must be turned automatically out of destructive winds to protect them. Some turn sideways, while others rotate vertically. Another way is to drag flaps from the tip of the blades. Most turbines reject power when the wind speed exceeds 30 mph.

15. Vertical Axis Wind Turbines (VAWT) Revised 020115 Savonius Darrieus with Savonius Panemone, 1000 B.C. Giromill

16. Horizontal Axis Wind Turbines (HAWT) Ref.: WTC Revised 020115 1.8 m 75 m American Farm, 1854 Sailwing, 1300 A.D. Dutch with fantail Modern Turbines ExperimentalWind farm Dutch post mill Middelgrunden

17. Energy Transmission zElectricity and hydrogen are energy carriers, not natural fuels zElectric transmission lines lose energy in heat (~2 to 5% as design parameter) zLine energy flow directional analysis can show where new energy plants are required zHydrogen is made by electrolysis of water, cracking of natural gas, or from bacterial action (lab experiment level) zPipelines can transport hydrogen without appreciable energy loss Revised 020115

18. Energy Storage zRenewable energy is often intermittent, and storage allows alignment with time of use. zCompressed air, flywheels, weight-shifting (pumped water storage) are developing zBatteries are traditional for small systems and electric vehicles; grid storage alternative zEnergy may be stored financially as credits in the electrical “grid” z“Net metering” provides the same cost as sale dollars to the supplier; 37 states’ law; needed in Florida www.strawbilt.org/systems/ details.solar_electric.html Revised 020115

19. Distributed Generation (DG) zDistributed generation occurs when power is generated (converted) locally and might be shared with or sold to neighbors through the electrical grid zDistributed generation avoids the losses that occur in transmission over long distances; energy used nearby zVarying wind and sunshine averages across several houses, blocks, cities, or states zSupply is robust, but precautions are required to protect electricity workers when main base-load power is out and system may feed back into powerlines Revised 020115

20. Generic Trades in Energy zEnergy trade-offs are required to make rational decisions  PV is expensive ($5 per watt for hardware + $5 per watt for shipping and installation = $10 per watt) compared to wind energy ( $1.5 per watt for hardware + $5 per watt for installation = $6 per watt total ) zAre Compact Fluorescent Lamps (CFLs) better to use? Ref.: www.freefoto.com/ pictures/general/ windfarm/index.asp?i=2 Ref.: www.energy.ca.gov/educati on/story/story- images/solar.jpeg Photo of FPL’s Cape Canaveral Plant by F. Leslie, 2001 Revised 020115

21. Legal aspects and other complications zPURPA: Public Utility Regulatory Policy Act of 1978. Utility purchase from and sale of power to qualified facilities; avoided costs zPower Plant Siting Act provides regulation by FERC zEnergy Policy Act of 1992 leads to deregulation zInvestment taxes favor conventional power zHigh initial cost dissuades potential renewable energy users zLack of state-level net metering hinders offsetting costs zRenewable energy credits needed to offset unlikely carbon tax on fossil fuels and “externalities” (pollution, health, etc.) z“NIMBYs” rally to insist “Not In My Backyard”! zNeed to consider beyond the first action; the results, and then what? Revised 020115

22. Conclusion zRenewable energy offers a long-term approach to the World’s energy needs zEconomics drives the selection process and short-term (first cost) thinking leads to disregard of long-term, overall cost zIncreasing oil, gas, and coal prices will ensure that the transition to renewable energy will occur ― How will we choose to do it? Revised 020115

23. References: Books zGipe, Paul. Wind Energy for Home & Business. White River Junction, VT: Chelsea Green Pub. Co., 1993. 0-930031-64-4, TJ820.G57, 621.4’5 zPatel, Mukund R. Wind and Solar Power Systems. Boca Raton: CRC Press, 1999, 351 pp. ISBN 0-8493-1605-7, TK1541.P38 1999, 621.31’2136 zBrower, Michael. Cool Energy. Cambridge MA: The MIT Press, 1992. 0-262-02349-0, TJ807.9.U6B76, 333.79’4’0973. zSørensen, Bent. Renewable Energy, Second Edition. San Diego: Academic Press, 2000, 911 pp. ISBN 0-12-656152-4. zDuffie, John and William A. Beckman. Solar Engineering of Thermal Processes. NY: John Wiley & Sons, Inc., 920 pp., 1991 Revised 020115

24. References: Websites, etc. Revised 020115 awea-windnet@yahoogroups.com. Wind Energy elist awea-wind-home@yahoogroups.com. Wind energy home powersite elist geothermal.marin.org/ on geothermal energy mailto:energyresources@egroups.com rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html PNNL wind energy map of CONUS windenergyexperimenter@yahoogroups.com. Elist for wind energy experimenters www.dieoff.org. Site devoted to the decline of energy and effects upon population www.ferc.gov/ Federal Energy Regulatory Commission www.hawaii.gov/dbedt/ert/otec_hi.html#anchor349152 on OTEC systems telosnet.com/wind/20th.html www.google.com/search?q=%22renewable+energy+course%22 solstice.crest.org/ dataweb.usbr.gov/html/powerplant_selection.html www.zetatalk.com/energy/tengx092.htm www.wind.enron.com/

25. Notes