Feasibility of Renewable Wind Energy: A comparison between home made and commercially produced

wind generators

Christian Ringer (100501251) – Construction & Environment – Regulation & Compliance

Christopher Timusk and Peter Lovrick – Construction & Engineering Technology

February 16, 2010

Transmittal Memo To: Christopher Timusk Centre for Construction & Engineering Technology Peter Lovrick Centre for Construction & Engineering Technology From: Christian Ringer 100501251 Construction & Environment – Regulation & Compliance George Brown College Date: March 11, 2010 Subject: Feasibility of Renewable Wind Energy: A comparison between homemade

and commercially produced wind generators In this paper comparisons will be made between homemade and commercially produced windmill turbines. In order to make this comparison, a homemade windmill generator had to be built. There was a lot of trial and error and primary research that went into the construction of the windmill generator, but the main elements are as follows: Preparation of windmill blades, finding an appropriate generator, creating a hub and mounting it for the windmill generator. The secondary research consisted of finding a common commercially produced windmill generator, its ability to output voltage and its overall efficiency. Some other secondary research also includes gathering wind data from local meteorological sources within the Toronto area. Some challenges that were encountered in this project included finding an appropriate generator that was cost effective and relatively local. In order to find an appropriate generator, testing was performed which required equipment not common to an average household, such as a voltmeter, an electric drill and a 10 ohm resistor. It is interesting to note the variety of methods that exist in order to construct a functioning windmill generator. New designs for windmill blades, hub, and generators are constantly appearing online, especially cost effective/do it yourself methods. The internet and online communities are a great way to find different ideas for homemade wind generators that are different from this paper’s. In closing, aspects of this thesis paper were challenging and required an element of craftiness and thriftiness. It is interesting to note the technology required to make a wind generator is not that new or difficult to understand. It was a great learning experience both technically and economically and hopefully this paper can help break down the barrier between the common household and acquiring affordable renewable energy.

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Table of Contents 1.0  Introduction ............................................................................................................. 1 2.0 Background and Literature Review.........................................................................2 3.0  Methodology ........................................................................................................... 3 

3.1  Windmill Blades ................................................................................................... 3 3.2 Generators ................................................................................................................. 4 

3.2.1 VAC Generator .................................................................................................. 4 3.2.2 VDC Generators ................................................................................................. 5 

3.3  Windmill Hub ....................................................................................................... 5 3.4  Mounting the Generator ....................................................................................... 7 

4.0 Experimentation ............................................................................................................ 8 4.1 Electric Motor Efficiency Test (VAC) ..................................................................... 8 4.2 Electric Motor Efficiency Test (VDC) ..................................................................... 9 4.3 Windmill Field Test ................................................................................................ 10 

5.0  Results ................................................................................................................... 11 5.1  Electric Motor Efficiency Test (VAC) ............................................................... 11 5.2  Electric Motor Efficiency Test (VDC) ............................................................... 11 5.3  Windmill Field Test ........................................................................................... 12 

6.0  Analysis of Results ............................................................................................... 15 6.1 Electric Motor Efficiency Test (VAC) ................................................................... 15 6.2 Electric Motor Efficiency Test (VDC) ................................................................... 15 6.3 Windmill Field Test ................................................................................................ 15 6.4 Cost ......................................................................................................................... 15

6.5 Efficiency………………………………………………………………………….15 7.0  Conclusion ............................................................. Error! Bookmark not defined. References .......................................................................... Error! Bookmark not defined. Bibliography......................................................................................................................19

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List of Figures Figure 1: PVC pipe ..............................................................................................................3 Figure 2: PVC pipe quartered ..............................................................................................4 Figure 3: Rough Blade .........................................................................................................4 Figure 4: Finished Blades ....................................................................................................4 Figure 5: VAC Test ..............................................................................................................5 Figure 6: Half Hub ...............................................................................................................5 Figure 7: Complete Hub.......................................................................................................5 Figure 8: C Steel ..................................................................................................................6 Figure 9: C Steel Holes ........................................................................................................6 Figure 10: Fastened Blades 1 ...............................................................................................7 Figure 11: Fastened Blades 2 ...............................................................................................7 Figure 12: Mounted Generator .............................................................................................7 Figure 13: VAC Generator...................................................................................................8 Figure 14: Drill ....................................................................................................................8 Figure 15: VAC Volt Meter .................................................................................................9 Figure 16:VDC Volt Meter ..................................................................................................9 Figure 17: VDC Test ..........................................................................................................10 Figure 18: Parking Lot ......................................................................................................10 Figure 19: VAC Results .....................................................................................................11 Figure 20: VDC Low Speed ..............................................................................................11 Figure 21: VDC Medium Speed ........................................................................................12 Figure 22: VDC High Speed ..............................................................................................12 Figure 23: Parking Lot Results ..........................................................................................13 Figure 24: Beach Results ...................................................................................................13 Figure 25: Wind Speed ......................................................................................................14 Figure 26: Commercial Generator .................................................................................... 16

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Abstract When comparing commercially produced and homemade wind generators, one must take into consideration price, efficiency and life. The construction of the windmill blades consisted of using recycled PVC pipe as the material for the blades. The pipe was used for its natural curvature, flexibility and ease of workability. Electric motors were used as a substitute in place of electric generators. After experimental testing it was deduced that only volts DC motors would supply an output of electricity. After much testing of VDC motors in a used motor warehouse, a suitable motor was found that has a high voltage output and a relatively low RPM. The amperage generated by the motor is also adequate enough to charge a 12 V led acid battery. The price of the electric motor was $ 30 CDN. The hub is an essential part of the project. It is the unit that mounts the windmill blades to the shaft of the electric motor. The hub was constructed of scrap end of an electrical housing unit. The work required some drilling and precision measurements, however in the end; a well balanced, symmetrical hub was produced. Once the major components of the windmill were constructed, they had to be mounted on a structure that would enable the windmill to pivot and stay faced in the direction of the wind. Using a scrap 2x4, scrap piece of thin laminated board, hose clamps purchased, a dolly wheel purchased, and various screws purchased for $ 20 total, a windmill stand was constructed. The unit has a rudder made of the laminated board that enables the windmill blades to stay facing the wind. When comparing the prices between homemade wind generator and the commercially produced wind generator, it is clear that the home made wind generator is much more cost effective. The price for constructing a homemade wind generator in this paper was $50 CDN compared to $ 899 CDN for a commercially produced wind generator. The efficiencies of the two generators are different in high wind speeds. The commercially produced generator is capable of producing 400 Watts at 45 km/h winds. However at 20 km/h wind speeds the commercially produced wind generator will output 12 volts at 2.9 amps. The homemade wind generator produces an average of 7.9 volts in 20 km/h winds. The uses for the two generators are the same; they are both used to charge a 12V battery. The rate at which the commercially produced wind generator charges a battery would likely be quicker and thus more efficient than the homemade generator but ultimately they both charge 12V batteries.

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1.0 Introduction The greatest challenge the construction industry faces today is building environmentally friendly buildings that use sustainable material and technology. One important element of sustainable development is a buildings ability to use renewable energy sources. In an ideal world, buildings would be able to utilize various renewable energy sources to ultimately go “off grid”, which means the building would be able to provide itself with ample heat and electricity that would not require the building to purchase either from the large providers (i.e. Toronto hydro). With threats such as global warming and lack of land availability, it is getting harder to produces enough electricity to meet the demands of growing populations. With the need for renewable sources of energy imminent, many homes and businesses have not yet made efforts to acquire such technology. This thesis paper will focus on one of the renewable sources of energy that can enable a building to go off grid, wind power. The idea is to conduct a feasibility study and see how cost effective and efficient wind energy can be, from both the commercial product, and the homemade. Thus, an inquiry into the effectiveness of one type of renewable energy was made; the viability of wind generators, both homemade and commercially produced. In order to look into the feasibility of homemade wind generators, a homemade wind generator had to be made for the reasons of testing and comparison. This is where the bulk of primary research was done. The primary research included testing various electrical motors for efficiency of voltage production with a voltmeter, creating effective windmill blades out of PVC pipe and fabricating a hub to mount the windmill blades to the electric motor from scrap material. The secondary research included finding alternatives to actual generators, researching wind speeds in Toronto, Ontario and researching a commercially produced windmill generator for the sake of comparison. The paper is organized into various sections, starting with the primary research organized into methodology, experimentation results and analysis. The conclusion section will provide the overall opinion held through the primary and secondary research that was completed.

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2.0 Background and Literature Review A generator is a device that converts mechanical energy into electrical energy. Generators produce a direct current and operate on the principle of magnetic induction. Magnetic induction is the principle that a voltage is created in a conductor when it passes through magnetic lines of flux. Generally, a generator has a loop (or loops) of wire that rotate around a shaft through two magnets of opposing forces. There are factors that increase the productivity and efficiency of a generator. The first factor is the amount of turns in a loop of wire. This increases the amount of voltage output. The second is the strength of the magnetic pole pieces. This increases the voltage as the stronger the magnets, the more lines of flux they produce, thusly creating more cut lines of flux per second as the looped wire passes through them. The third factor is the speed at which the magnets cut the magnetic lines of flux. Induced voltage is proportional to the number of flux lines cut per second. These three factors can easily be changed and altered to produce a generator of higher efficiency. 1 When wings or blades are attached to the shaft of a generator, it enables the wind itself to move the shaft of the motor, producing electricity. This is the general idea behind a wind generator. Turning wind into energy has been around since 18882, when the first person to create a windmill generator constructed a large yet inefficient windmill to produce electricity. Since then the designs of generators and specifically windmill generators have become more efficient and compact. Currently, wind generators have developed so much in the past 50 years you can buy them at local hardware stores that are small enough to erect in any backyard without causing an eyesore. Since the development of wind energy is not over and still in progress the price for commercial wind generators is still expensive. An electric motor operates on the same principles as a generator. With electric motors, when a current is introduced, it moves the shaft of the motor. Understanding this enables one to utilize old electric motors as generators. This can help individuals build their own windmill generators without having to know how to build a generator or pay more than necessary.3

1 Herman, S. L. 1999 pg 846 2 Dodge, D. M. 2001 pg 3 3 Herman, S. L. 1999 pg 962

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3.0 Methodology The primary research conducted in this thesis paper revolved around the construction of an efficient home made wind generator for the purposes of comparison to a commercially manufactured alternative.

3.1 Windmill Blades The construction of the windmill blades was a very crucial step in creating a homemade wind generator. The blades size and weight determine how much torque can be produced by the wind in order to turn the shaft of your actual generator. The blades that were designed for the home built generator came from a technique developed adopted by an online source.4 First, a 4 inch diameter PVC pipe that was ¼ of an inch thick was cut into 4 equal quarters.

Figure 1, PVC pipe (Ringer 2010)

4 Davis, M. 2006, Para 8

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Then a blade design was drawn up on the quartered pipe and cut using a jig saw.

Figure 2, PVC pipe quartered (Ringer, 2010) Figure 3, Rough Blade (Ringer, 2010) The blades were then given a rounded edge on the exterior side of the blade and a sharp edge on the interior side of the blade in order to shape it more like a wing.

Figure 4, Finished Blades (Ringer 2010)

3.2 Generators For the purpose of this assignment, electric motors were used as generators since they are essentially the same thing and operate on the same principles. Many motors were used and tested; however, only one efficient motor was chosen to act as the generator.5

3.2.1 VAC Generator An electric motor was purchased and tested in place of a generator. The exact specifications of the motor are: Marathon Electric, 120 V (alternating current), 3.8A at 3420 RPM. This means when 120 V is introduced into the motor, spins the shaft at 3420 RPM and produces 3.8 amps.

5 Herman, S.L. pg 962

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3.2.2 VDC Generators When finding a VDC generator, many motors were tested at a electric motor distributing warehouse in new market. None of the findings were recorded on camera due to faulty batteries. However, after testing 6 electric motors with a drill that rotated at 1250 rpm, and putting the generator through a 8 ohms resistor, it was found that the most efficient motor was a 48 VDC motor. Once this motor was selected, it was tested at home by attaching it to the same drill that rotates at 850 rpm, and measured its efficiency on a voltmeter as shown.

Figure 5, VAC Test (Ringer, 2010)

3.3 Windmill Hub For the windmill’s hub, an old electrical box was used. The electrical box has a circular metal disk that was used as the hub. With a measuring tape, the center of the disk was found and drilled. When constructing the windmill hub, it is important to ensure measurements and drilling is precise to ensure the blades can rotate properly and do not wobble.

Figure 6, Half Hub (Ringer, 2010) Figure 7, Complete Hub (Ringer, 2010)

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Once all the holes were drilled, fastening it onto the electric motor shaft was next. A C – shaped piece of steel was fitted through the shaft, this piece was to fasten the hub to the shaft.

Figure 8, C Steel (Ringer, 2010) Two more holes were drilled into the hub to match the C-shaped steel fastener.

Figure 9, C Steel Holes (Ringer, 2010) Once the hub was fitted, the blades were attached to the hub with bolts and nuts. Then once the measurements between the tips of the blades were all equal, one extra hole was drilled into each blade to fasten the blade into position.

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Figure 10, Fastened Blades 1 (Ringer, 2010) Figure 11, Fastened Blades 2 (Ringer, 2010)

3.4 Mounting the Generator With the generator complete and constructed, it had to be mounted to a stand so that it could erected for future use and testing. A 2x4 piece of wood was cut to 3.5 feet. A scrap piece of thin chip board was cut into a rudder shape and was fastened to the 2x4 with steel 90 degree angle brackets. The actual generator was mounted to the 2x4 with hose clamps. A spare wheel from a dolly was used as the pivoting device so that the generator can stay pointed in the direction of on coming wind.

Figure 12, Mounted Generator (Ringer, 2010)

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4.0 Experimentation

4.1 Electric Motor Efficiency Test (VAC) In this test, an electric motor was tested for its efficiency. The motor was a 120 VAC 3420 RPM type electric motor, meaning it required 120V alternating current to spin the shaft 3420 RPM. The motor was being tested for electrical output in voltage by spinning the shaft of the motor with a drill of known RPM

Figure 13, VAC Generator (Ringer, 2010)

Using a corded drill that runs at 850 RPM max, the drill was attached to the shaft of the electric motor and spun at various speeds by controlling the amount of pressure on the trigger.

Figure 14, Drill (Ringer, 2010) Once the leads were hooked up to the corresponding leads of the voltmeter, the drill was spun and the output of the VAC motor was recorded.

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Figure 15, VAC Volt Meter (Ringer, 2010)

4.2 Electric Motor Efficiency Test (VDC) In this test, a 48 VDC motor was used. The RPM output is not known as is it not listed on the motor itself. What is known is that 48 volts direct current is required to spin the shaft of this motor. The purpose of this test was to measure the output in volts of the electric motor.

The first step was hooking up the positive and negative leads of the motor and the volt meter.

Figure 16, VDC Volt Meter (Ringer, 2010) Next, the drill was attached to the shaft of the motor and spun at various speed by controlling the amount of pressure on the trigger. The results were recorded.

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Figure 17, VDC Test (Ringer, 2010)

4.3 Windmill Field Test In this test, once the windmill was constructed, it was tested in the field in various locations throughout Toronto on a day of relatively regular wind speeds. The objective was to record the output in voltage using only wind power. The first step was to hook up the leads of the motor and the voltmeter, once they were hooked up, the windmill was pointed by hand into the direction of the wind and the voltage was recorded.

Figure 18, Parking Lot (Ringer, 2010)

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5.0 Results

5.1 Electric Motor Efficiency Test (VAC) In this test, once the leads of the electric motor were connected to the volt meter, and the drill was running at full speed (850 RPM), the motor was outputting 0.2 volts.

Figure 19, VAC Results (Ringer, 2010)

5.2 Electric Motor Efficiency Test (VDC) In this test, the drill trigger was depressed low, medium and all the way (full speed 850 RPM). The results were at low speeds, the VDC motor output 14.9 volts DC.

Figure 20, VDC low speed (Ringer, 2010) At medium speeds, the VDC motor output 21.3 volts DC.

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Figure 21, VDC Medium Speed (Ringer, 2010) And at full speed, 850 RPM, the VDC motor out put a maximum of 23.6 volts DC.

Figure 22, VDC High Speed (Ringer, 2010)

5.3 Windmill Field Test In a parking lot located on Helena street and Bathurst street in Toronto, Ontario, the windmill was pointed in the direction of the wind, and using just wind power, the windmill laws able to reach an average of 4.38 volts. The wind speed in the parking lot felt weak and not particularly strong at all.

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Figure 23, Parking Lot Results (Ringer, 2010) The next location was cherry beach located in Toronto, Ontario. There the wind was more aggressive than the parking lot, and the windmill averaged 7.9 volts with the more aggressive winds.

Figure 24, Beach Results (Ringer, 2010) The average wind speed for the city of Toronto on Sunday February 14th 2010 was approximately 21 km/h.

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Figure 25, Wind Speed (Weather Stats, 2010)

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6.0 Analysis of Results

6.1 Electric Motor Efficiency Test (VAC) The results from this test show that electric VAC motors are not suitable as generators for a home made windmill, they do not output any where near the amount of voltage required to do anything. Also, alternating current can not be stored in a battery cell.

6.2 Electric Motor Efficiency Test (VDC) The results from this test show that this VDC motor was very efficient as a generator for a windmill. In order to charge a 12 volt battery, 12 volts at 1 amp is usually what is required.6 This motor clearly outputs more than 12 volts at varying speeds. What is not shown is a test where the motor was hooked up to a resistor that would act like a battery. When the motor was spun, the motor put out the high of 24 volts at 2.5 amps. This is more than ample electricity required to charge a 12 volt battery.

6.3 Windmill Field Test The results from this test showed that on an average day in Toronto, the wind that is available for the home built wind generator would output 7.9 or 8 volts. Throughout the day, with wind spikes and lows, eventually, it is assumed that the wind generator would have the power to charge a 12 volt battery.

6.4 Cost One aspect that is worth noting is the cost of the home made wind turbine. The PVC pipe was scrap from a jobsite so the cost was free. The VDC motor cost $ 30 from a supplier. The hub was free as it was just an old electrical cover. All extras such as bolts, nuts, 90 degree steel brackets and screws cost approximately $20. The tools used for this project were all on hand. For a grand total of $50 dollars, an efficient wind turbine was built. A Sunforce 12-Volt 400-Watt Wind Generator can be found at Canadian Tire for $899 dollars.

6 Ries, V. 1999, para 2

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Figure 26, Commercial Generator (Canadian Tire 1997 – 2010)

6.5 Efficiency When comparing the two generators, the commercially produced wind generator has the following list of wind speeds and corresponding voltage output located on the box of the actual wind generator: Wind Speed Voltage Amperage 12 mph (or 19.3 km/h) 12 2.9 On the day of the testing for the home made wind generator, the wind speed for Toronto averaged out to be 20 km/h. In those wind speed conditions, the generator output an average of 7.9 volts. From this, it is evident that the commercially produced wind generator is more efficient.

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7.0 Conclusion When looking at what it is windmill generators do, it is easy to compare the homebuilt wind generator to the store bought wind generator. They both will be used to charge a 12 volt battery and both of them will succeed in doing that. The cost of the homebuilt generator is a fraction of the cost of the store bought, and they both accomplish the same task. The difference is the store bought wind generator may be more efficient that the home made wind generator, allowing more energy to be produced, and potentially allowing for more energy to be sold back to the grid. Also, it is likely that the store bought wind generator will last longer than the home built wind generator, this is merely an assumption based on the fact that the motor purchased for the home built wind generator was used and its history is not known. At the end of the day, the home made wind generator could be made more efficient with adjustments made wherever necessary. The ability of the homemade wind generator to become similar in effectiveness and efficiency to a commercially produced wind generator is possible; it would just take monitoring and adjusting. The homemade wind generator has limitless potential based on the constructors experience and knowledge of electrical components and craftsmanship. However experience in any trade is not required to construct a functional home made generator, just a little bit of reading and time is all it takes to make a functioning wind generator for a fraction of the price of a commercially produced wind generator.

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References Davis, M. (2006). How I home-built an electricity producing wind generator. Retrieved December 1st, 2009, from Mikes World website: http://www.mdpub.com/Wind_Turbine/index.html Dodge, D. M. (2001 – 2006). Illustrated history of wind power development. Retrieved February 12th, 2010, from Telos Net website: http://www.telosnet.com/wind/index.html Gipe, P. (2004, March). Wind power: renewable energy for home farm and business. White River Junction, VT: Chelsea Green Publishers. Haris, K. (2006). How I built a wind generator in my backyard for $150 Retrieved Feb 9th 2010 from website: http://www.thekevdog.com/projects/wind_generator Herman, S.L. (1999). Delmar’s standard textbook of electricity. (2nd ed.) Albany, NY: Delmar Publishers Jensen, N.O. (1983, September). A note on wind generator interaction. Retrieved Feb 1st 2010 from: http://www.risoe.dk/rispubl/vea/veapdf/ris-m-2411.pdf Miller, T.M. (2004, Sept 20). Build a simple charge controller for wind and solar power systems. Retrieved December 1st, 2009, from fieldlines website: http://www.fieldlines.com/story/2004/9/20/0406/27488 Ries, V. (1999 – 2010). How to charge a 12 volt battery. Retrieved Jan. 3rd 2010 from: http://www.ehow.com/how_4813873_charge-volt-battery.html Smith, N. (2004). Alternator and generator comparison for wind power Retrieved Feb 3rd 202 from website: http://www.otherpower.com/otherpower_wind_alternators.html Sullivan, K.R. (2004). Understanding the alternator Retrieved Jan 27th 2010 from website: http://www.autoshop101.com/trainmodules/alternator/alt101.html Weather stats. (2005, May 20). Weather for Toronto, Ontario: wind speed. Retrieved from: http://toronto.weatherstats.ca/wind_speed

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Bibliography Clarke, S. (September 2003). Electricity Generation Using Small Wind Turbines at Your Home or Farm. Retrieved February 1st, 2010, from Ministry of Agriculture Food and Rural Affairs website: http://www.omafra.gov.on.ca/english/engineer/facts/03-047.htm Davis, M. (2006). How I home-built an electricity producing wind generator. Retrieved December 1st, 2009, from Mikes World website: http://www.mdpub.com/Wind_Turbine/index.html Dodge, D. M. (2001 – 2006). Illustrated history of wind power development. Retrieved February 12th, 2010, from Telos Net website: http://www.telosnet.com/wind/index.html Gipe, P. (2004, March). Wind power: renewable energy for home farm and business. White River Junction, VT: Chelsea Green Publishers. Haris, K. (2006). How I built a wind generator in my backyard for $150 Retrieved Feb 9th 2010 from website: http://www.thekevdog.com/projects/wind_generator Herman, S.L. (1999). Delmar’s standard textbook of electricity. (2nd ed.) Albany, NY: Delmar Publishers Jensen, N.O. (1983, September). A note on wind generator interaction. Retrieved Feb 1st 2010 from: http://www.risoe.dk/rispubl/vea/veapdf/ris-m-2411.pdf Karsil, V.M. (2010). Renewable energy: International journal (Volume 28, Issue 5) Gaziantep, Turkey: Elsevier Science Ltd. Miller, T.M. (2004, Sept 20). Build a simple charge controller for wind and solar power systems. Retrieved December 1st, 2009, from fieldlines website: http://www.fieldlines.com/story/2004/9/20/0406/27488 Ries, V. (1999 – 2010). How to charge a 12 volt battery. Retrieved Jan. 3rd 2010 from: http://www.ehow.com/how_4813873_charge-volt-battery.html Smith, N. (2004). Alternator and generator comparison for wind power Retrieved Feb 3rd 202 from website: http://www.otherpower.com/otherpower_wind_alternators.html

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Sullivan, K.R. (2004). Understanding the alternator Retrieved Jan 27th 2010 from website: http://www.autoshop101.com/trainmodules/alternator/alt101.html Weather stats. (2005, May 20). Weather for Toronto, Ontario: wind speed. Retrieved from: http://toronto.weatherstats.ca/wind_speed