A wind turbine, or alternatively referred to as a wind energy converter, is a device that converts the wind’s kinetic energy into electrical energy. A concise history can be found in its Wiki at https://en.wikipedia.org/wiki/Wind_turbine.
Wind turbines are manufactured in a wide range of vertical and horizontal axis. A vertical axis wind turbine has its axis perpendicular to the wind streamlines and vertical to the ground. A more general term that includes this option is “transverse axis wind turbine” or “cross-flow wind turbine.” A wiki for these is at https://en.wikipedia.org/wiki/Vertical-axis_wind_turbine. The vertical axis tends to be less efficient than the horizontal axis though. Here’s a treatise on that: hhttps://www.windpowerengineering.com/vertical-axis-wind-turbine-technology-continues-improve/.
When you look at the prices for blades for any of the commercial units, the DIY stuff rules. Blade tech is expensive tech BUT one can build comparable quality for far less money. Nooooo—PVC is not carbon fiber BUT it doesn’t cost as much either. Presented here are several links to some inexpensive ideas. There are MANY types of blades. Most of them work. How well they work is the question and that’s specific to your situation and needs.
Always look to YouTube for DIY stuff. https://www.youtube.com/watch?v=NolB5BbQnBc.
Here’s a step-by-step plan for a DIY vertical axis wind generator: https://www.instructables.com/id/Building-a-Vertical-Axis-Wind-Turbine-VAWT-/
Why wind turbines have 3 blades: https://interestingengineering.com/the-scientific-reason-why-wind-turbines-have-3-blades.
How they are designed: https://en.wikipedia.org/wiki/Wind_turbine_design.
One of the main components of any wind turbine is its blades. These catch the air and cause the generator to do its thing. There are many designs and configurations of these. There are few comparative tests on these, especially the DIY stuff.
A lot of designs “work”. Many work better. A few are super. Blade science is physics!