1. The economics of Wind Power: According to a recent article, the average cost of constructing a 1.0 MW land-basedwind power generator is approximately US$1.37M. What is the average cost for energy (dollars/kW) to construct a wind power facility? (Note: If you can find the current cost of such a wind power facility, let me know.)

2. List some of the reasons that the output power of a wind generator might be less than its rated power.

3. Calculate Wind Power.

The equation for the maximum power that can be extracted from a fluid flow, whether wind or tidal current,follows from the kinetic energy of fluid motion. In an open fluid stream, it is proportional to the third power of the flow speed; the available power increases eightfold when the wind speed doubles. The power is also proportional to the cross-sectional area of the flow that's intercepted, A, & to the density of the fluid, . Finally,Betz's law states that the maximum power that can be extracted by turbine blades is approximately 59% of the available kinetic energy. Thus,

P = (59%)(1/2)Av³

Use this equation to estimate the maximum power of one of the monster wind turbines that GE is developing, a Haliade-X machine (see "A monster wind turbine is upending an industry", p. D1, Boston Globe, 2 Jan.'21). Assume blades 100 m in length(which means that the blades sweep out a circular area, pr², with a radius of 100 meters) & air at sea level (density 1.29 kg/m³) with average speed of 22.5 mph (about 10 m/s).

Ans.: 12 MW

4. One of the common arguments against wind power is that it will contribute to bird mortality. The American Wind Energy Association (AWEA) argues that the mortality rate due to wind turbines is small compared to other sources of bird mortality, including: automobiles, airplanes, windows in buildings and cats. (Note the updated links in references 7 & 19 for this week's material on wind power.) Another concern expressed regarding the Cape Wind project is that the project may prove economically unsustainable, raising the possibility that wind turbines may eventually be abandoned, leaving an environmental hazard. Also, read what Muller says about wind power. What is your assessment of these arguments?