Venturi wind turbine

Basic design idea

There are a few reasons why I though this idea should be built and tested; while looking to buy a wind turbine for a family member who is off-grid, the general consensus points to pole mounted turbines with blade diameters of 2 meters and above. The general rules of thumb to get value for money are: a good location to capture the more consistent laminar flowing winds, and the higher you can put it and the less structures around, the better. This requires having a lot of space to install one, and planning permission is needed before it’s erected.  So if you don’t have the right location for one of these structures to be able to perform well then the next option is to go for a smaller device that you could rig up in a garden or on a garage roof etc, unfortunately these don’t produce much energy due to the smaller sized devices having a smaller swept area, and turbulent winds at lower heights.

This design I hope will solve the issues of the small turbines. The following I hope to resolve.                      

1. Swept area size – rather than increase the swept area I’m trying to increase wind speed: the method for accomplishing this is the Venturi housing. Example:- if the wind speed is increased by around 2x then the energy increase would be around 8x this can be seen in the following known formula as the windspeed has the greatest effect upon energy generation.

P= 1.2 (air density) x swept area x the windspeed(cubed)

2. Turbulent wind – when the wind is turbulent short burst don’t keep the turbines running in the generating zone (usually above 3m/s). Capturing the energy from short bursts of wind: this will be accomplished by using a mechanical storage device, so rather than directly coupling the blade rotor to the alternator the mechanical storage device will sit between the two. The idea is short bursts will be stored and released when the amount of energy stored is enough to produce useful energy from the alternator.