This prompted me to think with other turbine designs that are more efficient and have less wind drag as compared to my existing Savonius turbine. Anyway, earlier this morning I was busy setting my small test fixture that will test 2 other types of vertical axis wind turbine. We have an old anemometer that we no longer use and found that I can use the optical sensor to measure the relative wind speed of the turbine under test.
Not bad at all, the Savonius turbine able to spin at 0.2m/s., rotation sometimes varies over time but is still provides me a consistent slow rotational speed.
The next is a Darrieus turbine installed in the fixture. It has a hard time getting to start initially even if the wind is moving at the blades at substantial speeds. It sways back and forth until it catches the right angle and start to spin rapidly. I was able to get an average of 0.5m/s wind speed as displayed in the anemometer unit but it is not self-starting, not a good candidate for my project.
The last model of turbine that I'm going to test is the Lenz turbine. From the appearance of the model, it looks like a combination of Savonius and Darrieus turbine.
The performance is very promising, it automatically start to spin rapidly and I was able to obtain an average of 0.8m/s of wind speed reading from the anemometer unit.