Page 1. The Flux Capacitor 12/2/09. Joshua Jefferies. Isaak Samsel. Austin Bootin. Brian Plaag. Team A1-5, EF 152 Sec. A1

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1 Page 1 The Flux Capacitor 12/2/09 Joshua Jefferies Isaak Samsel Austin Bootin Brian Plaag Team A1-5, EF 152 Sec. A1

2 Page 2 Project Overview The purpose of this project is to transform the mechanical energy of the wind into useable electrical energy. In order to accomplish this, we will employ the principle of Faraday s law of induction, which, in laymen s terms, states that changing magnetic flux induces an electric current. Changing magnetic flux can be achieved by changing a magnetic field, or changing area through which magnetic field lines flow. We will perform the latter. We will design and build an apparatus which will spin a magnetic core within many windings of conductive wire, thus constantly changing flux back and forth from some maximum value to zero. The device will be operated by a wind-powered propeller, and light a light bulb, thus transforming the mechanical energy of the wind into useable electrical energy. A brief history of wind energy The first uses of wind energy, dating back to the first century A.D., were windmills that were used for pumping water. During the Middle Ages windmills were used to churn grain into flour. Charles F. Brush was the first to use a windmill to generate electrical power. The windmill was used to produce 12 kilowatts of electrical power for 20 years. Smaller systems have been used to power some appliances and lighting on farms. These can produce around 1-3 kilowatts of power. In 1931 Russia developed the Balaclava, an industrial wind generator capable of producing over 100kilowatts of power. The largest windmill ever built was the Smith-Putnam machine developed in This generator was capable of producing 1.25 megawatts, but due to its size, one of the blades broke off within several hundred hours of operation. In 1974 the U.S. launched the Federal Wind Energy Program which, until 1981 was considered very successful in research and development of new ideas for wind powered generators. Through

3 Page 3 many billions dollars invested and many years of research wind powered generators today are much more efficient, collectively producing almost 9 Gigawatts of power in the U.S. alone. [1][2][3] Design Process The first thing our group did when designing was brain storm several ideas. We went through several concepts for the structure and operation of the generator and rotor. These included a standing device using gears to transfer the energy to spin the magnets, and two separate props and axes to rotate both the coil and the magnets in opposite directions. Both of these ideas were ultimately discarded to keep it simply and save time. We also went through several ideas to increase efficiency, including attempting to cool it with dry ice to attempt cause the coil material to approach superconductor status. We had problems with the initial wire purchased for the coil, as the insulation was far too thick to be of any use. We debated over what to use for the prop for some time, whether to buy or build one, what to use for blades, and what to use for a hub. Device Description The final device is very simple. A fan spins magnets inside of a coil, which generates the current for the bulb. For the fan, we ultimately decided to use a tight spread of blades, cut out of aluminum cans (Diagram 1). We used a circular plastic sheet for the hub, supported by a wooden washer. We used a brass rod purchased at Hobby Town for the axel, and mounted with metal brackets to a wooden baseboard. The rod was inserted into the coil through rubber bearings, and the Neodymium N52 grade magnets were attached inside (Diagram 2). The coil was 28 gauge thinly insulated generator wire, wound between times.

4 Page 4 Diagram 1 Diagram 2 Efficiency The device is not very efficient. In order to get an accurate calculation of the efficiency of our device, we have to look at the system as a whole. The way in which the device was

5 Page 5 tested involved using an electric fan; the fan is rated for a power input, so calculating efficiency is easy. Since = Where η is the efficiency of the system (percentage), P Output is the actual electrical power generated by our device (in Watts), and P Input is the power going into the fan that generates the wind (again in Watts). We already know the power input of the fan, since the rating is written right on the back of the fan: 180W. To know the power output, we employ a voltmeter and an ammeter. The maximum voltage output was measured at 1.2Volts, and the maximum current was 0.05Amps. Since = Where P is Power (Watts), V is voltage, and I is current (Amps). We calculate the maximum power output to be 0.06W. We then apply our efficiency equation in order to determine the efficiency of the fan-generator system to be %. In other words, it s a good thing efficiency wasn t the goal of the project. Conclusion After the windmill was finally assembled and refined we were successful in lighting up the light bulb. The bulb would flicker due to the fan being off balance, but would stay lit. While completing the windmill project the group learned a great deal about generating electricity from a conductive coil and magnets, such as the great deal of strength the magnets needed to possess and the number of winds the wire needed to create the necessary amount of voltage and current to light the bulb. We also applied aerodynamic concepts to the prop, to harness as much wind energy as possible.

6 Page 6 The main problems we had with completing the project were minimizing the friction of the axel and finding the proper wire to conduct the current. The initial wire proved to be useless, and we were forced to start the coil a second time, which turned out much better. The best way we could have improved the efficiency of the device would have been spending more time on the prop. If we had more time and funding, we could have created a much more efficient way to harvest the wind energy. The final product still turned out well, and worked beyond a doubt.

7 Page 7 Bill of Materials NID magnets: $12.98 Copper wire: $18.47 Bracers (stands): $2.18 Scrap wood: $1.00 Busch cans: $0.20 Copper rod: $0.54 TOTAL: $35.37

8 Page 8 References [1] National Renewable Energy Laboratory, available at URL: (Viewed December 1, 2009) [2] TelosNet An Illustrated History of Wind Power Development, available at URL: (Viewed December 1, 2009) [3] Electricity from Windmills, available at URL: (Viewed December 1, 2009)