Last updated: December 28. 2014 2:36AM
By Wolf D. Fuhrig
For as long as ships needed to be propelled, sails have been employed to make use of wind energy.
Today, large wind farms consist of hundreds of individual wind turbines connected to a network of electric power transmission. They compete with coal, gas and other fossil fuels. Offshore winds tend to be steadier and stronger than on land, but construction and maintenance costs are considerably higher. Small onshore wind farms can feed some energy into the grid.
In 2013, Denmark was generating more than a third of its electrical energy from wind while 83 countries were using wind power to supply their electricity grid. Wind energy production had reached some four percent of total worldwide electricity usage, and it was growing rapidly.