Performance - Wind Energy: Renewable Energy and the Environment - page 171

8.10 COMMENTS
Wind turbine and wind fa r m perfor mance (annual, qua r terly, monthly, or by per iod of pea k demand)
will determine economic viability and will help in comparisons of wind turbines. The main per-
formance factors are the amount of energy produced and the cost of that energy compared to other
sources. Of course, electricity is the major application, with water pumping secondary. Capacity
factors in good to excellent wind regimes should range from 30 to 40%, and annual specific outputs
should be over 1,000 kWh/m 2 . For wind farms, availabilities of 98% and turbine lifetimes of 25 or
more years should be the norm with good preventative maintenance programs.

LINKS
Global Wind Energy Council, www.gwec.net .
Performance for Vestas 47, Vestas V80, www.hullwind.org .
Windicator, www.windpower-monthly.com/wpm:WINDICATOR . Published quarterly in Windpower
Monthly .

REFERENCES
1. R. N. Clark. 1983. Reliability of wind electric generation . ASAE Paper 83-3505.

2. W. Pinkerton. 1983. Long term test: Carter 25. In Proceedings, Wind Energy Expo '83 and National

Conference , ed. V. Nelson, p. 307.

3. F. S. Stoddard. 1990. Wind turbine blade technology: A decade of lessons learned, 1980-1990,

California windfarms . Report, Alternative Energy Institute, West Texas A&M University.

4. WindStats Newsletter . www.windstats.com .

5. Wind Performance Reporting System, California Energy Commission. PDF reports. www.energy.

ca.gov/wind . Electronic Wind Reporting System. Query from database, 1985-2005. http://wprs.
ucdavis.edu .

6. B. D. Vick, R. N. Clark, and D. Carr. 2007. Analysis of wind farm energy produced in the United

States. Paper presented at Proceedings , Windpower 2007. CD.

7. P. Volund, P. H. Pedersen, and P. E. Ter-Borch. 2004. 165 MW Nysted offshore wind farm. First year

of operation—Performance as planned. www.2004ewec.info/iles/24_0900_pervolund_01.pdf .

8. W. Cleijne. 1990. Literature data base on wind turbine wakes and wake effects . NT-TNO Report

90-130, TNO, Apeldoorn, The Netherlands.

9. P. B. S. Lissaman. 1994. Wind turbine airfoils and rotor wakes. In Wind turbine technology , ed. David

A. Spera. New York: ASME Press, p. 283.

10. D. L. Elliott. 1991. Status of wake and array loss research. In Proceedings, Windpower '91 , p. 224.

11. C. B. Hasager et al. 2007. Wind resources and wind farm wake effects offshore observed from sat-

ellite. Risoe National Laboratory, Wind Energy Department. www.risoe.dk/rispubl/art/2007_79_
paper.pdf .

12. M. B. Christiansen and C. B. Hasager. 2005. Wake effects of large offshore wind farms identified from

satellite SAR . Remote Sensing of Environment 98:251.

13. M. Méchali et al. Wake effects at Horns Rev and their influence on energy production. www.dongenergy.

com/NR/rdonlyres/575EFE4E-CB73-4D4D-B894-987AC9008027/0/40.pdf .

14. R. N. Clark and R. G. Davis. 1993. Performance of an Enertech 44 during 11 years of operation. In

Proceedings, Windpower '93 , p. 204.

15. K. Pokhrel. 2001. Performance of renewable energy systems at a demonstration project. Master's

thesis, West Texas A&M University.

16. V. Nelson, N. Clark, and R. Foster. 2004. Wind water pumping . CD. Alternative Energy Institute, West

Texas A&M University. Also available in Spanish.

17. R. N. Clark. 1992. Performance comparisons of two multibladed windmills. In Eleventh ASME Wind

Energy Symposium , SED-Vol. 12, p. 147.