Features of wind power
· Wind turbines have a main rotor and an electrical generator at the top, pointing directly at the wind.
· To find out the direction of the wind, small wind turbines use a wind vane and larger wind turbines use a wind sensor along with a servo motor.
· A gearbox is used to turn the rotation of the blades faster to run an electrical generator.
· The blades are stiff, thereby stopping the blades from being pushed to the tower in high wind situations.
· Also, the blades are positioned with some distance from the tower and are tilted towards the wind.
Source: Wikipedia: Wind turbine. (2003, April 3). Retrieved April 24, 2010, from http://en.wikipedia.org/wiki/Wind_turbine#Horizontal_axis
· Rotor Blades: Use wind’s energy and transform it into rotational energy of shaft
· Shaft: Sends the gathered rotational energy into the generator
· Nacelle: Capsule containing:
· Gearbox : adds to the energy of the shaft and is placed between rotor hub and generator
· Generator: Converts the rotational energy from the shaft to electricity by using electromagnetism
· Electronic control unit: controls the system; turns off the turbines when there is an emergency or error and monitors yaw mechanism
· Yaw controller: Turns the rotor to the wind direction
· Brakes: used to stop the movement of the shaft during system error or overload
· Tower: holds the rotor and the nacelle and elevates the entire system so that the blades can move freely
· Electrical equipment: transfer the electricity from the generator down the tower and monitors safety rudiments of turbine.
Source: How stuff works: North Carolina State University Professor Marsha. (1998). How wind power works. Retrieved April 24, 2010
Source: Horizontal-axis Turbine . (1998). Retrieved April 24, 2010, from
http://science.howstuffworks.com/wind-power.htm/printable
Source: Darling, D. (1999). Operating Principles of HAWT . Retrieved April 24, 2010, from
http://science.howstuffworks.com/wind-power.htm/printable
Disadvantages:
The biggest problem is that the wind varies in particular areas where the wind turbines are located. Therefore, it is not a constant power source. The wind usually is the strongest in fall, winter, and early spring. It decreases during the summer months. It needs planning and careful design, and then we will be able to use it efficiently. We can also install batteries to store extra electricity and use electricity when needed.
The second problem is the unwanted sound for the people who live near the wind turbines; the faster it spins the more sound it produces. In order to solve this, people can decrease the unwanted sound by installing quieter, low-rpm wind turbines. Also, wind turbines have mechanisms that slow down the rotations of the rotor blades in cases of high winds. Furthermore, it is better to build higher towers, which reduces the sound on the ground levels.
Another problem is that there aren’t many places that we can build wind turbines because hills and valleys, and trees and forests can reduce the amount of wind. This can be solved by building a higher tower, as mentioned before, and moving the turbine into higher velocity winds to achieve a greater output.
Source: Chiras, Dan. Power from the Wind. Gabriola Island, Canada: New Society Publishers, 2009. Print.
Where best to build a wind turbine
Source: British Columbia predicted wind speed map
The above map, published for BC Hydro, displays the average predicted wind speed at 65 metres above the ground (the average height of a wind turbine) for different areas of British Columbia. The orange and red areas are classified as having good/very good average wind speed (above 6 m/s), the light green areas are classified as having fair average wind speed (4-6 m/s) and the dark green areas classified as having poor average wind speed (below 4 m/s). As seen on the map, the greatest areas of very high wind speed are in the Coast Mountains and the Cassiar Mountains (beside the Alaskan panhandle). Unfortunately, these areas are too rugged and mountainous to be accessed and used effectively for wind generation. Thus, the other areas that have been identified by BC Hydro as potentially useful for wind generation, circled on the map, are northern Vancouver Island, the Prince Rupert/Queen Charlottes area, and the Peace River region.
Background/Benefits/Drawbacks of wind power in each particular area.
Source: Holt
-northern Vancouver Island
-BC Hydro has surveyed the possibility of building land-based wind turbines near the coast
-Wind generally flows constantly from the northwest and from the southwest
-Projected 6.5 – 8.0 m/s average wind speed
-600 MW realistic power potential
-Benefits: Closer physical proximity to the Vancouver-Victoria populated areas than the Peace or Prince Rupert areas
-Drawbacks: -Lower projected power potential than the Peace or Prince Rupert areas
-Many of the potential sites are located in sensitive coastal ecosystems
-The coastal terrain is quite rugged, there are few roads that reach the north-western side of the island
-Little existing high-voltage transmission infrastructure in the area
-As a result, costs would be higher due to the need to install new access and transmission infrastructure
-the areas near Prince Rupert and the Queen Charlottes
-Possibility of wind turbines located off-land in the Hecate Strait that separates Prince Rupert from the Queen Charlottes
-Also possibility of on-land turbines located on islands near the coast as well as areas further inland, such as Terrace
-Constant flow of wind from the southeast
-Projected 6.5 – 8.5 m/s average wind speed on land
-Projected 9.0 – 10.0 m/s average wind speed over ocean
-500 MW realistic energy potential on land
-1400 MW realistic energy potential over water
-Benefits: Higher power potential than Vancouver Island, strong constant winds especially over water
-Drawbacks: -Many of the areas both on and off land are quite ecologically sensitive
-Coastal terrain is quite rugged, with few access roads
-Little existing high voltage power infrastructure in the area
-Building turbines and laying cable in ocean areas carry higher construction costs than building on land
-
the Peace River region in north-eastern British Columbia
-Wind turbines would likely be located in highland areas
-Constant flow of wind from the west
-7.5 – 10.5 m/s projected average wind speed
-1900 MW realistic power potential
-Benefits:-Strong constant winds provide for a high power potential
-Close proximity to existing high voltage infrastructure in place for the Bennett and Peace dam projects
-Closer proximity to existing access infrastructure such as rail and road
-Drawbacks: -Very rugged highland terrain
It appears that the Peace River region is currently the best location to build a wind turbine in BC. This is because it has a higher potential capacity than in other areas, and has a closer proximity to existing infrastructure. This is probably why BC’s first and only operational wind farm project, the 34 turbine, 102 MW Bear Mountain Wind Park, is located in the Peace River area. (Map of Installations). This is also an explanation for the lower cost of Peace River area wind power, which is shown below.
However, there is also another proposal undergoing federal environmental review, the NaiKun project, that plans to construct 110 turbines, with a total 396 MW capacity in the Hecate Strait off the northeast corner of the Queen Charlottes. NaiKun is touting its site’s benefits as having the highest potential wind speed and energy capacity, as well as the fact that the offshore project is located away from populated areas, which it believes will reduce complaints from residents that the turbines are unsightly and will reduce the heard noise. (NaiKun)
Generation Cost Estimates for Wind Power.
Source: Holt
Note: It is projected that most wind power in BC will be generated by private companies and then sold to BC Hydro at a rate that is proportional to the generation cost. The projected sale costs that BC Hydro will have to pay are listed below for each location
-Vancouver Island: $0.09-$0.20 per KWh
-Prince Rupert/Queen Charlottes: $0.11 - $0.26 per KWh
-Peace River: $0.08-$0.15 per KWh
It is estimated that the generation cost for the average large hydroelectric installation is $ 0.11 per KWh. (Walden) When the generation costs of wind power are compared to this, they can be competitive with large hydroelectric projects in numerous cases.
BC Hydro’s residential rate for electricity is $6.27 - $8.78 per KWh. (Residential Rates) This means that the majority of the cost of electricity is the transmission cost, which would be $6.16 - $8.67 per KWh.
As a result, at current levels, the total cost of wind power would be $6.24 - $8.93, depending on where the wind turbines were located. It can be concluded that wind power is becoming a competitive form of electric generation.
Bibliography
Source: Wikipedia: Wind turbine. (2003, April 3). Retrieved April 24, 2010, from http://en.wikipedia.org/wiki/Wind_turbine#Horizontal_axis
How stuff works: North Carolina State University Professor Marsha. (1998). How wind power works. Retrieved April 24, 2010
Horizontal-axis Turbine . (1998). Retrieved April 24, 2010, from http://science.howstuffworks.com/wind-power.htm/printable
Darling, D. (1999). Operating Principles of HAWT . Retrieved April 24, 2010, from http://science.howstuffworks.com/wind-power.htm/printable
Chiras, Dan. Power from the Wind. Gabriola Island, Canada: New Society Publishers, 2009. Print.
British Columbia predicted wind speed map (n.d.). Retrieved April 24, 2010, from http://www.bchydro.com/etc/medialib/internet/documents/environment/pdf/environment_wind_energy_resource_map_pdf.Par.0001.File.environment_wind_energy_resource_map.
Holt, J. A., & Eaton, D. J. (2008). Assessment of the energy potential and estimated costs of wind energy in British Columbia (E ed. ). Garrad Hassan Canada. Retrieved April 24, 2010, from http://www.bchydro.com/etc/medialib/internet/documents/info/pdf/rou_wind_garrad_hassan_report.Par.0001.File.rou_wind_garrad_hassan_report.pdf
Map of installations (2008). Retrieved April 24, 2010, from http://www.canwea.ca/farms/wind-farms_e.php
NaiKun. (2007). Retrieved April 24, 2010, from http://www.naikun.ca/index.php
Residential rates (2009). Retrieved April 24, 2010, from http://www.bchydro.com/youraccount/content/residential_rates.jsp
Walden, T. (2006). Relative costs of electricity generation technologies. Canadian Energy Research Institute. Retrieved April 24, 2010, from http://www.cna.ca/english/pdf/studies/Comparative_Costs_of_Generation_Technologies_Sept-06-EN.pdf
