Windmill Blades

Hello and welcome to the windmill blades blog. I have made this blog to help answer your questions regarding how to design your wind turbine blade, how your generator should work, your windmill tower design and any other questions you might have. All the information you find here is thanks to this renewable energy website so have a look for yourself.


What is the best windmill blade design

The design of your blades depends on a few different factors which are:

• Wind velocity
• Rotor size
• Generator size

Wind Velocity

The speed of the wind will determine firstly the number of blades that your windmill will have. If there is:

• a low wind speed of 7-10 mph then I would recommend more than 3 blades with a smaller diameter. Make sure the blades are made out of light material such as balsa wood or thin PVC with a twist to them. Also attach the blades to the rotor at quite an angle to allow for more efficiency.

• a high wind speed will require 3 blades with a bigger diameter and also with more length to them as well. You can still use wood and I also recommend acrylic or light weight sheet metal. These materials allow to design more of a twist to the blades and also to sand the edges to a bit of a point. Still attach them to the rotor at an angle to allow for increased efficiency.

Rotor Size

The size of the rotor will determine how quickly it will rotate, therefore the bigger the rotor the longer the blades should be. You generally want to make the rotor as big as you can, depending on the wind velocity, because this allows for a higher ratio for your generator turbine. The rotor is linked to the generator turbine at a higher ratio to increase the energy generated per revolution.


This is the simplest example I can give where the rotor would be the white gear and the turbine would be attached to the red gear. The ratio would be determined by the generators size and voltage capacity.





Generator size

This generally relates to a bigger generator because then you need to increase the ratio and revolutions of the turbine in order to get enough energy to generate the energy you are after. You would only go for a bigger generator if there is high wind speed, therefore a longer and wider blade.

More Homemade Windmill Instructions

If you want to get a complete instruction kit that will show you how to make a homemade windmill from scratch have a look at the renewable energy website link at the top/right of this blog for access to a great source.