Wind is a wonderful source of power – if it is available. Almost everyone would like to talk about using wind power, but hardly anyone knows how much wind is available at their site. And in most cases, it is not as much as they imagine.
Consider that the start up speed of most small wind turbines is about 7 miles per hour and that turbine output is normally rated at about 27 miles per hour, and you realize that you need a strong, steady wind to make much power.
Often customers ask for very large turbines of 100kW or larger. Turbines of that size are meant for connection directly to the grid, and would not be appropriate for battery charging (unless you had an enormous battery bank!). Battery charging turbines are usually not larger than 5kW.
In some part of the world, wind maps are available which can give a rough idea of the expected wind speed in your area. However, most of Africa remains unmapped, so testing at the specific site is the best solution. You can either use a small turbine like the Air Breeze or Air X, or buy a anemometer with data logging capability to measure the annual wind production at your site. If that is not possible, you can estimate based on turbines installed in your area and geographic features. SouthWest WindPower publishes this guide which can be helpful.