1. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.20 A sketch of the electromechanical system for converting wind turbine power to electric power, housed in the turbine hub pod.

2. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.21 A plot of the ratio of wind turbine power P to rated power P r as a function of the ratio of wind speed V to rated wind speed V r, as in (8.19).

3. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.22 A U.S. map showing areas graded by the annual average wind energy flux ρV 3 /2, with darker areas indicating higher wind energy flux. (Elliot, D. L., et al. Wind Energy Resource Atlas of the United States.DOE/CH 10093-4.Golden,Colo.:Solar Energy Research Institute,1987.)

4. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb

5. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb

6. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.25 A plot of effectiveness as a function of capacity factor for a wind turbine having C p = 16/27.

7. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.26 A row of wind turbines at a wind farm in Palm Springs, California. (By permission of DOE/NREL-PIX.)

8. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.27 The total power output from all wind farms in the Republic of Ireland for the month of February 2007. (Data from MacKay, David. Sustainable Energy–Without the Hot Air. Cambridge, UK: LIT Cambridge Ltd., 2009.)

9. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.28 A sketch of the cross-section of a tidal power pool with dam.

10. Copyright © 2011 by Oxford University Press, Inc. Energy and the Environment James A. Fay / Dan S. Golomb FIGURE 8.29 The pool and ocean levels, as well as power output, of a single effect tidal power plant during one tidal cycle. (Data from Fay, J., and M. Smachlo. J. Energy, 7 (1983): 529.)