Revision as of 10:00, 18 February 2016 by ***** (***** | *****)
Small wind energy devices i.e. heigth up to 4 m and width 2 m, which have no external rotating parts are environmentally friendly and easy to install and maintain.
If devices with effective heigth 2,5 m and width 2 m were deployed in a number equal to the number of motor vehicles in the world, the electricity production from the devices in fresh breeze (8,5 m/s) would constitute about 56 % of the world electricity production.
According to ref. 1 the number of vehicles in service worldwide surpassed 1 billion in 2010.
According to ref. 2 the world electricity production in 2013 was 23 322 TWh which is equal to 23 322 billion kWh.
An example of a small wind energy device is shown at ref. 3. This device is assumed to produce 1,5 kW in 8,5 m/s wind.
If the annual average electricity from each device was 1,5 kW the amount of electricity produced per year from 1 billion devices would be 1,5 (kW) x 24 x 365 (number of hours per year) x 1 billion = 13 140 billion kWh.
This constitute about 56 % of the world electricity production.
1,5 kw from a device with effective area 2,5 x 2 m and overall efficiency 0,75 requires a wind energy density of 400 W/m^2.
At ref. 4 you can find information about the average wind energy density in your area. Please note that the available energy depends on the altitude of the energy converter components in relation to the ground.
The terrain around the wind energy device may both decrease and increase the wind energy density. In som cases a building wall can locally increase the wind energy density.
Before deciding to buy a wind energy device the wind speed at the site should be measured by means of a Wind Speed Meter. For examples of such meters see ref. 5.