Recently, our school took part in a Skills Canada competition. We had a choice to either create spaghetti bridges or wind turbines. Niall and I decided we would work together to enter the wind turbine competition, since spaghetti bridges are kind of finicky. 

   

First, we had to come up with a design. This involved testing different shapes and sizes of blades, as well as angling the pitch to create the most efficient design possible. We asked ourselves: which wind turbine blade design will generate the most electricity? We did some research and found that two blades were efficient, three blades still more efficient, and four even more efficient, although not by much.

   

We then created an hypothesis: that three blades would make the most power, but that two would be harder to mess up, since you only have to make two identical blades instead of three or four. There were many variables, such as the number of blades, the blade shape, length, width, pitch, etc. We couldn’t change the distance from the wind source, the max power of the wind source, the size of the generator that the blades were mounted to, or the strength of the turbine base, etc. 

   

To build our turbine we used: 5” wooden dowels, cardstock, and a 12-hole mounting hub. We cut out a design stencil and traced 4 copies onto cardstock. We glued the cut-out blades on either side of the dowels (two per dowel) so that just enough dowel stuck out to fit into the hub. Then we inserted dowels into the hub so that only the blades were seen; and we placed the hub onto the generator as per the competition instructions.

   

At the end of our experimentation, we were able to achieve a total of 4.3 volts with the fan given to our school. Unfortunately, the fan used in the actual competition was far weaker than the fan we used during testing, and so we got a max of 3.2 volts in the testing stage, and about the same amount in the judged part. 

   

We managed to get first place in both competitions. Sawyer and David achieved second place. Our team will now be moving on to the Provincial Competition in Abbotsford. The second-place team will come if another team doesn’t show up.

  

In conclusion, we found out that two blades work better than three or four; but that's just our opinion.

 

- Kahlio Dryburgh