Installing a wind turbine is mostly dependent on whether you have (sufficient) wind at the location or not. Due to local obstacles (buildings, trees, infrastructure), even 50 m difference in the location can make a huge difference in the power production.
So how can this be solved? We will have to look into a couple of criteria for the location of the wind turbine. These criteria can be the distance to grid, obstacles like buildings or vegetation (trees), location in valleys, or the distance to other installations or infrastructure. We will discuss this in more detail below.
Distance to obstacles
The graphic above shows already that we need a certain distance to obstacles like buildings or trees to avoid turbulences. So if our house is 15 m high, the nacelle of the wind turbine should at least be 30 m high (a little more to also avoid that the rotating blades suffer from turbulence effects). The wind turbine should then be located at least 300 m away from the obstacle (in wind direction).
These simple numbers explain already why wind turbines in built environments will not work, especially not at heights which are similar or even smaller than the height of the obstacles. If wind comes typically from one direction (in Northwestern Europe typically from West or Southwest) there might be an option to avoid turbulences at least for the prevailing wind direction.
Distance to grid
The concept of de-centralised energy means that energy is consumed where it is produced. That means that any small or mid-size wind turbine will have to be located close to a home or a small industry to keep the distance from the turbine to the grid as small as possible. We can therefore hardly avoid that such wind turbines stand close to a building or trees, hence working with lesser wind than large wind turbines, especially when the hub height is small.
It is therefore inevitable to know the wind speed at our site as accurately as possible. Measurements need to be performed (see next topic), ideally over a period of at least 6 months.