By Isha Sadiq, Imane Elkeria, Sanaa Latif and Umakayar Cumar Wind Turbines By Isha Sadiq, Imane Elkeria, Sanaa Latif and Umakayar Cumar

Introduction: This team consists of four members, Isha Sadiq, Imane Elkeria, Sanaa Latif and Umakayar Cumar who study at Slough and Eton church of England business and enterprise college. Thank you very much for this wonderful opportunity BP, as we feel it has enhanced and developed our use of planning and collaboration. We have brilliant ideas and strategies that we would like to include into this project, and we hope you will be able to notice our potential from our organised work. The reason why we decided to choose the project of making an efficient Wind Turbine, is because we feel the urgency and stress of green and efficient technology. As we already know, Climate change is causing dramatic impacts on the environment and that is due to humans using products which run on energy, obtained from burning fossil fuels. With that said, we hope you enjoy reading and understanding our plan, as much as we enjoyed making it.

What Is It? Blades Nacelle containing the generator and gear box Tower A wind turbine is a device which converts kinetic energy from the wind into electrical power. We will be testing to find the most efficient wind turbine that wastes as less energy as possible. Furthermore, a wind turbine is a source of green energy as it uses natural energy sources in order to convert it into the desired energy. Also they are environmental friendly as well as there is a lack of fossil fuels, so companies are now trying to find other efficient ways of producing energy. One of them, is by designing renewable energy sources such as a Wind turbine. Nacelle containing the generator and gear box Tower Foundation

Wind Turbine Structure The best structure for a wind turbine is a tubular tower. The best materials for the tower are steel or concrete, and for additional protection, zinc alloy. The nacelle contains the main drive shaft, therefore it must be hollow, however strong enough to hold everything within it. There are many suitable materials for the blades, however the best would be fibreglass. Other options could be lightweight woods (however that is a fire hazard) or aluminium. A simple image illustrating a typical wind turbine. An Image showing a Nacelle and its fundamental structure.

Blade Shape Airfoil shaped blades are the most efficient blades. They are designed as uneven teardrops. The downwind side has a large curve, whilst the upwind side is reasonably flat. This makes the air move faster on the curved side of the blade; therefore there is less pressure on this side. The difference in pressure on the opposite sides causes the blades to move quicker allowing less energy to be wasted.

Number Of Blades The number of blades does effect the wind turbine, as the more blades there are the less power each blade can extract from the wind. This is because of the limitation of power in the wind. However, if you do wish to have a lot of blades on the wind turbine, they all must be quite narrow to maintain the aerodynamic efficiency. For this reason, most large turbines do not have more than three blades, however they also do not have less than 3 blades, as it is said that wind turbines with 1 or 2 blades, seem quite visually disturbing! As you can see, most Wind turbines critically have 3 blades, as that is the best amount to complement the aerodynamic efficiency of a blade.

Planning We are planning to investigate what makes the most efficient wind turbines, whether that is its shape, size or material. After researching, we have come to the conclusion that the most efficient wind turbines are primarily due to the shape of the blade as this can effect how much energy is obtained. We would like clarify that to do this experiment we find it very important that we introduce some of our knowledge. Firstly we understand that efficient energy is the process of gaining more useful energy than wasted energy. We also have a clear understanding of how the shape of an object can effect how quickly it moves through air. Furthermore, the reason for why we have quite a sharp blade is due to the idea of streamlining. So by making the shape a lot more sharp, it can rotate faster as there is less air resistance.

Hypothesis Self Assessment: Hypothesis: To find what makes the most efficient wind turbine. See which variables affect the speed and energy the turbine produces; whether it be the blade size, shape, material or angle. To investigate this we will make 3 different styles of blades and test which is most efficient. Equipment needed: Fan (wind source) Glue Gun Bamboo Skewers Balsa wood Cardboard Felt Carving knife Self Assessment: We have purposely decided to only use equipment that is light, but firm in order to achieve an efficient working wind turbine. For example the Balsa wood has a good thickness as well as it is light, in order to allow the spin of the turbine to be a lot more effective.

Variables: How we will make sure that our experiment is as fair as possible? We will make sure that we follow our criteria of our variables. We are only changing one thing, which is the shape of our blade as we are only testing for one thing. How will we make sure we gain accurate results? We will repeat the testing of our blade three times and make sure we record the exact numerical data we gain from the testing. Independent variable: Shape of the blades Dependant variable: The amount of time taken for the blades to wind the mass up completely. Controlled Variables: Weights used Wind source Size of blade

Making the best Blade: In order for our experiment to be as fair as possible, we have created 3 different types of blades, which allows us to experiment 3 individual blade shapes. The advantage of this is we will obtain the knowledge of which blade shape is the most efficient. For us to produce the best possible blade shapes, we have researched everything about wind turbines- as you would have seen throughout the PowerPoint. For us to be able to assemble all the blades in time, we all went home and did extra work- may it be any extra research for the most efficient wind turbine or even making the blades.

Preliminary Testing: Axel Blades Axel Blades Fan Blue Tac Blue Tac Add a weight of 1 gram to the end of the turbine and using a fan, time how long it takes for the weights to make 5 full turns around the turbine using a stopwatch. However if in any case the amount of Blue Tac you add is too light or too heavy for the blade, then adapt the weight you add on to the strength of your blade. The same with the string if, it is too long or too short then cut it to the right length. This is known as preliminary testing. After that record your results onto a table, and repeat each experiment at least 3 times to gain accurate results. Axel Blades Axel Blades Fan Blue Tac Blue Tac Stand Fan

Blade 1 Blade 1 is made out of medium thick balsa wood, carved using a carving knife. The blades are shaped as uneven teardrops (an Airfoil shape). Each blade has a skewer on the centre-back for additional support. There are 3 blades, as the less blades there are the more wind each blade can obtain. However there are not 1 or 2 blades, as research claims that wind turbines with less than 3 blades are quite visually disturbing to people, and maybe even nearby animals. All 3 blades are positioned slightly tilted. This makes it easier to catch wind from every direction. Front Back

Blade 2 Blade 2 is also made out of medium thick balsa wood, carved using a carving knife. This blade’s shape is uneven, with a straight side on one and then the other is slightly curved this makes the air move faster on the curved side of the blade; therefore there is less pressure on this side By making our blade sharper, we are creating a much more streamlined shape, this therefore results in the blades rotating faster, and so obtaining more energy There are also 3 blades, so that the wind turbine spins evenly as well as it’s not visually disturbing. Front Back

Blade 3: Method Step 1. Step 2. The method for making blade 3: The shape of Blade three is: quite sharp from one side, which gives them a more streamlined shape. The advantage of this is that the blades can then cut through the air and spin much quicker. The method for making blade 3: Step 1. First we drew our designed blade shape onto a piece of card, using a pencil and ruler to make sure our measurements were as accurate as possible. Step 2. Then using sharp scissors, we cut out our first blade shape, in order to use it as a template to draw out the blades that we were going to layer on top of each other, in order to create the perfect thickness.

Blade 3 Method: Step 3. Step 4. Final Product for Blade 3: Front: After drawing the blade shape 10 times onto card, using the template we sketched out earlier; we cut the blades out using scissors. Final Product for Blade 3: Step 4. Then after all the blades were cut, we stuck 5 of the blades together using glue. Then stuck down the other 5 blades together, leaving us with two firm blades. We then cut a bamboo stick in half using scissors, and using a glue gun we stuck a bamboo stick on both the blades. After that we inserted our blades into a polystyrene ball and stuck them firm, with a glue gun in order for it to not be wobbly and as a result, lose energy. Front: Back:

Time taken to wind up mass in seconds: Results Table: Time taken to wind up mass in seconds: Blade Number: Test 1: Test2: Test 3: Average in Seconds: Blade 1: 2.59 2.62 2.67 2.63 Blade 2: 3.18 3.00 3.37 Blade 3: 1.87 1.78 2.00 1.90 The results were recorded onto this results table. Our results were determined by how long it took the string and the blue Tac to wind around the axel of the blade. The quicker it took for it to wind up, the more efficient the blade, and this shows that our blade is very strong, quick and efficient. We repeated our experiment three times in order to gain accurate results, and then found an average from the three results.

Number of seconds it took for the blade to wined up the string. Graph: Type of Blade: Number of seconds it took for the blade to wined up the string.

Conclusion: Conclusion: This experiment tested which type of blade is most efficient in producing the most energy. There were no anomalous results, so this proved our experiment to be fair and accurate. The results varied from 1.90 seconds as being the quickest time and 3.18 seconds being the slowest. These results suggest that Blade 3 produced the most energy and therefore is most efficient, whereas Blade 2 was the slowest and so therefore it was the least efficient. So overall we can now conclude that the faster the blade, the more efficient it is as it produces more energy due to: the angles of its blade, the shape of the blade and the strength.

Thank you for Watching: Thank you very much BT for this great opportunity, and we hope that our PowerPoint has met your high expectations. We assure you that so much effort has gone into perfecting and designing this Power Point.