1. We have determined the average wind speed at a height of 30 m is ₃₀ = 5.47 m/s. We need a wind speed of 7.5 m/s to generate enough power for a financially viable wind project. If the surface roughness factor is a = 0.2, calculate the hub height which allows us to reach wind speeds of 7.5 m/s.

2. Assuming Rayleigh distribution and for the same average speed of 7.5 m/s, calculate the i) wind power and ii) electrical power if the overall efficiency of wind -> electricity conversion is 43% and turbine diameter is 50 m. Assume air density is 1.225 kg/m³.

3. We have a row of 10 Siemens An Bonus turbines, each with a with a rated power of 2.3 MW. What diameter blade (D) would provide us an annual capacity factor of 35%, if the average wind velocity is 7.5 m/s? How much energy (in MWh) is produced per year? If there is 0.5% loss in power generation per year, how much energy is produced in the year 25?

4. Assume the wind farm of part d) operates over 25 years but ignore the yearly 0.5% loss. Assume the installed cost (capital, taxes, etc.) is $5,200,000 per MW of rated power. Assume a MACRS depreciation incentive is offered according to the table below (similar to what we discussed in the wind lecture). Assume O&M costs are $500,000 per year.

Installed Cost				$1,000,000
Corporate Tax Rate				25%
Corporate Discount Rate				6%
Year	MACRS	Depreciation	Depreciation Tax Savings	PV of Tax Savings
1	10%
2	10%
3	10%
4	20%
5	15%
6	15%
7	5%
8	5%
9	5%
10	5%
			Total Savings
			Net System Cost

1. Fill out the table above and submit with your assignment (you can use an excel worksheet to fill out the table). What are the total savings for every $1,000,000 of installed system cost?

2. What is the installed cost before MACRS?

3. What is the installed cost after we apply the MACRS?

4. The project is financed over the 25 years with a 6% interest loan. What is the annual payment? (hint: you need to annualised the installed cost from iii above over 25 years and also include the O&M costs). What is the cost of electricity $/kWh?