代写ENERGY 722, 2025 - Assignment 3 Wind Resources & Turbines代做留学生Python程序

ENERGY 722, 2025 - Assignment 3

Wind Resources & Turbines

Assignment objective:

Show your understanding of the Wind Resources & Turbines Lectures.

This assignment is expected to be undertaken completely independently.

Due Date:

11.59pm, 28 April 2025, submitted online through Canvas.

Lateness policy:

If you cannot complete the assignment in time due to extenuating circumstances, please contact Michael MacDonald in advance of the deadline to arrange an extension. If an assignment is submitted late (without a prior extension) a penalty of 10% (of the total marks available) per 24 hours will be deducted. No assignments will be accepted more than 48 hours late without prior arrangement.

Value:

20% of your final grade for the ENERGY722 course.

Show your working where appropriate. You will be graded for lay-out and format (e.g., correct referencing, clear figures, appropriate number of significant figures given, clearly stated assumptions, etc.) as well as correct numerical results.

Queries:

Please direct questions on content to Michael: [email protected];

General questions to Bart: [email protected]

Marking sheet:

	Total Available	Marks
Q1	4
Q2	5
Q3	5
Q4	4
Q5	10
Q6	6
Overall work, lay-out, presentation	4
Final mark	38

Question 1: [4 marks]

Three profiles from different sites are given below (in the figure and table). By fitting the logarithmic velocity profile (assume K  = 0.4), estimate the roughness lengths for the three sites. State what ground surfaces these roughness lengths likely represent.

Question 2: [5 marks]

Two possible sites for wind turbines are suggested:

A. one, in a dense forest (z0   = 0.4  m) near a city where a mean wind speed of U10   = U(z = 10  m) = 7.1  m/s was measured, and which could support a wind turbine with a hub-height of 60 m and blade length of 26 m; and

B. two, a remote, snow-covered open terrain (z_0=0.0019 m) with U_10=10.4 m/s which could only support a wind turbine with hub height of 44 m and blade length of 22 m.

For both scenarios, compute the power available in the wind using the logarithmic velocity profile,  using the wind velocity at the hub height and assuming it is constant over the entire swept area.

State which of these two sites you think is preferable and explain why. You should consider potential features of the site (stating any assumptions) in addition to the potential power available.

Question 3 [5 marks]

The original Brooklyn Wind Turbine was constructed in 1993 and became an icon of Wellington. It was recently replaced in 2016 with an even larger wind turbine. Citing your source(s) state the name, class and size (hub height and blade length) of the two turbines. Why was this particular turbine class chosen?

Next, find the annual energy output and compute the capacity factor of the original and new wind turbines. Briefly explain why the capacity factors might be different.

Question 3 [5 marks]

The small town of Ōpunake (near Mt Taranaki) wants to install a wind turbine near the  town, to attract tourists and provide enough electricity for approximately one third of households/dwellings in the town. Stating your assumptions and references, provide an approximate estimate of the size (blade length) of the wind turbine required. You can neglect any vertical variation from any wind speed mapping data you use and simply assume an appropriate capacity factor and turbine efficiency.

Question 4 [4 marks]

You work for a small consultancy specialising in projects involving wind energy. Your company has been engaged to give some information to a power company on wind turbine sizing and power production for a possible wind turbine. The power company has narrowed down its choices to two possible wind turbine designs, both with a rated power of 810 kW, and a hub height of 60 m.

The wind turbine is to be located near a collection of industrial buildings, with a roughness length Z0 = 0.2 m. Long term meteorological records for wind speed and direction at an open grassland terrain (Z0 = 0.002 m)  near the  proposed  site are available from an anemometer mounted at a height of 20 m. They have been analysed, and it has been found that the distribution of wind speed (irrespective of direction) can be fitted by the Weibull distribution, with the parameters: A = 0.9, C = 11.0, k = 2.0.

The Weibull distribution is given by

                            (1)

Differentiating the Weibull distribution results in the probability density function yields                                                                                                        (2)

Answer the following questions. Include working where appropriate; excel sheets or code scripts (e.g. Matlab/Python) can be uploaded to Canvas as separate files.

a) Plot the probability density function for the wind speed at the hub height of the wind turbine. Show how you computed the appropriate value for C.

b) An ENERCON E-48 turbine is proposed to be used on the site. Using the

manufacturers data (see the pdf attached), compute the capacity factor and  annual energy output (AEO) for this turbine. Assume the cut-out speed is 28  m/s. Show your working (e.g. an excel spreadsheet or Matlab/Python script).

c) The second proposed turbine is the ENERCON E-53. Repeat your analysis from

b) for the E-53 to compute the capacity factor and AEO.

d) Explain why your answers for b) and c) are different, despite the two turbines having the same rated power.

Question 6 [6 marks]

Discuss the advantages and disadvantages between horizontal and vertical axis wind turbines, in less than a page (excluding references). Where possible, relate the discussion to concepts taught in lectures. Include situations/locations where you expect each turbine to be used, and why they are suited for those locations.