Obstacles Can Ruin Your Small Wind Turbine Project

Small wind turbines can be the best way to cut home energy costs.

There are several places you can locate a wind turbine on your property and there are pros and cons of each:

1. Roof - it is certainly easier to get one mounted here since you don't have the expense of putting up a foundation and a tower. However, the wind is more turbulent less reliable on roofs.

2. Tower - this is the ideal solution for where to place your wind turbine. The reason for that is the tower places the wind turbine up higher, where the wind is more stable.

The wind velocity and consistency is not the same everywhere on your property. In general, the wind down low is turbulent and the wind up higher, unobstructed by trees and buildings, is more stable. Also, the higher up in the air you go, the greater the speed of the wind as well.

Here are a couple of wind "rules of thumb" to keep in mind:

1. The higher you mount your turbine, the stronger and more consistent the wind. There are diminishing returns here. Also, beyond 200 feet in altitude near an airport, the Federal Aviation Administration gets involved because the tower is a potential hazard to landing aircraft.

2. The lower you mount your turbine, the more turbulent and inconsistent the wind. The roof can be a great answer for where to locate your windmill. The biggest downside you may face is the potential damage to your roof. Since the wind is somewhat turbulent there, your wind turbine will be subject to side stresses.

3. The higher you go, the more power you will produce, but the more it will cost to locate the turbine there. You are definitely talking about a tower here with a minimum recommended height of 30 feet above the tree line, or 30 feet above the tallest obstruction within 10 times the rotor height.

Another wind phenomenon you need to carefully consider is "shelter effect". Shelter Effect is what happens when wind becomes more turbulent when it passes around your home, other structure, or trees, etc.

As you can imagine, this can be a real problem for farms with wind turbines because of placing the wind turbines in open fields, surrounded by tree lines. The wind breaks created by tree lines create a lot of turbulence.

Obviously the further away you get from the obstacle, the less the shelter effect. However, you really can't avoid turbulence as far as 20 times the height of the obstacle.

If you aren't able to mount your wind turbine up high, on account of space restrictions or local permitting limitations, mounting it low will still produce electrical energy, but not as efficiently as a small wind turbine mounted optimally after a thorough understanding and mapping of the wind on your property.