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Mechanical Engineering

Constructive Response Task (Sample)：Wind Power Generation
Wind power generation is the conversion of wind kinetic energy into electricalenergy or electricity, through the use of wind turbines. In recent years, there has
been much interest in wind power generation as one of the measures against
global warming, mainly for two reasons. Firstly, compared to other forms of small‐scale power plants, it can generate electricity inexpensively. Secondly, its emissionof carbon dioxide per unit power generation is relatively low.
Figure 1 shows the total amount of electricity supplied by wind power generation,worldwide, between 1997 and 2014. According to this figure, the capacity of windpower generation has grown by more than 10 percent each year, amounting tomore than fifty times factor increase during the past 17 years. In order to improve
the overall cost effectiveness of wind power generation e.g. in wind farms, anumber of design parameters need to be taken into account including thelocation, wind turbine structure and design, safety systems, etc.
Respond to the following questions which focus on the wind turbines used forwind power generation from a mechanical engineering point of view.

Figure1. Growth in electricity supplied by wind power generation worldwide
Source：The Global Wind Energy Council , Global Wind Statistics 2014.
http://www.gwec.net/wp‐content/uploads/2015/02/3_global_cumulative_installed_wind_capacity_1997‐2014.jpg

1

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Mechanical Engineering
Question 1. Examine the locational condition or site of a wind farm for wind power
generation.
Figure 2 shows a wind farm for wind power generation. List and explain two reasons
below why this is a good site for wind power generation.

Figure 2: An example of a wind farm
Photograph of Otonrui Wind Farm, provided by Horonobe City

Reason 1:

Reason 2:2

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Mechanical Engineering

Question 2. Examine the “shape of the blades” of wind turbines used for wind power
generation.
Compare the shapes of the blades for a traditional windmill and a wind turbine shown in
Figures 3a and 3b, respectively. Explain from a mechanical engineering point of view two
features of blades that characterise wind turbines for wind power generation.

Figure 3a Traditional windmills.

Figure 3b Wind turbines used forwind power generation.

Martijn Roos. www.mroosfotografie.nl
http://free‐photos.gatag.net/2014/11/07/040000.html

Design Feature 1:

Design Feature 2:

3

http://sozai‐free.com/sozai/01541.html

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Mechanical Engineering

Question 3. Examine the “Number of blades” of a wind turbine for wind power generation.
From a mechanical engineering point of view, identify three advantages of having many bladesor few blades, and provide possible explanation why large‐scale wind turbines used for wind
power generation often have three propeller type blades.
Reason 1:

Reason 2:

Reason 3:

Possible explanation from above:4

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Mechanical Engineering
Question 4. What are the “responsibilities of a mechanical or power engineer” in designingwind turbines for wind power generation?
Only one year after the wind turbine was constructed, it became apparent that the windvelocity could be larger than assumed in the initial design. In order to prevent the collapse ofwind turbine column due to strong wind, identify three potential countermeasures that aretechnically possible for different levels of risk. For each countermeasure, evaluate theiradvantages and/or disadvantages from a broad perspective, including the non‐technicalaspects.

Countermeasure 1:

Countermeasure 2:

Countermeasure 3:5