Performance - Wind Energy: Renewable Energy and the Environment - page 173

Information for problems 8-10. Today, Carter is not manufacturing wind turbines, and Vestas
V27 is not in production.

Specifications Carter 300 Vestas V27

Diameter, m 24 27

No. blades 2 3

Rated power, kW 300 225

Tower height, m 50 31.5

Installed cost (IC), 1990 $100,000 $225,000

Estimated annual energy, kWh 600,000 500,000

Weight specs, kg
Rotor

1,340 2,900

Tower head (nacelle) 2,091 7,900

Tower 8,023 (includes gin pole) 12,000

Guy cables, winch 1,336

Control box and panel 155

Total 14,250 22,800

8. For the Carter 300, calculate (a) kWh/m 2 , (b) $IC/kW, (c) kWh/kg, and (d) kWh/$IC.
9. For the Vestas V27, calculate (a) kWh/m 2 , (b) $IC/kW, (c) kWh/kg, and (d) kWh/$IC.
10. Estimate the annual capacity factor for the Carter 300 and Vestas V27.
11. Go to the Vestas web page, www.vestas.com. (a) For the Vestas V52 (1.65 MW), estimate
the annual kWh/m 2 for a good wind regime. (b) For the Vestas V90 (3 MW), estimate the
annual kWh/m 2 for a good wind regime.
12. For the farm windmill, what is the approximate pump diameter if the water depth is 40 m.
Approximately how much water could be pumped in a light wind?
13. For the farm windmill, what is the approximate pump diameter if the water depth is
20 m? Approximately how much water could be pumped in a light wind?
14. For the farm windmill, what is the approximate pump diameter if the water depth is
100 m? Approximately how much water could be pumped in a fair wind?
15. For the farm windmill (use Figure 8.14 for flow data), estimate water pumped for 1 month
that has an average wind speed of 5 m/s. Use Rayleigh distribution (1 m/s bin width).
16. Check the Internet to see which companies sell wind-electric water pumping systems.
17. For the wind-electric water pumping system (use Figure 8.14 for flow data), estimate
water pumped for 1 month that has an average wind speed of 5 m/s. Use Rayleigh distri-
bution (1 m/s bin width).
18. For an annual average wind speed of 6 m/s, compare the predicted annual energy produc-
tion for the Enertech 44 for the 25 kW and 60 kW wind generators. Use Figure 8.8 for
power curves and use Rayleigh distribution (1 m/s bin width).
19. Electronic Wind Performance Reporting System is available online [5]. For the last year
available, what is the statewide energy production for California? Which manufacturer
had the largest installed capacity? Which manufacturer had the largest number of tur-
bines installed?
20. By approximately what percent will bugs on blades reduce the power?
21. Select a wind farm that is close to your home town or city. What is the installed capacity?
How much electricity did it produce last year? If values are not available, estimate from
installed capacity and capacity factor.
22. Are there any village power systems in your country? If the answer is yes, determine if
performance data are available for one system. What is the size of the system and annual
energy produced?