Potential

Availability of wind energy

Wind energy is actually solar energy. Incident solar radiation results in pressure differences in the atmosphere, which causes air to move. Approximately 2.5% of incident solar radiation is converted into (horizontal and vertical) wind energy in this way. Of the total quantity of solar energy that reaches the surface of the earth, we need to effectively use less than 0.01% to be able to provide for our total worldwide, human energy demand. In other words, the worldwide quantity of wind energy is approximately 250 times bigger than the current total energy demand (if all of the energy in this wind could be produced at 100% efficiency). This is more than enough wind to provide for the world’s overall energy demand. So, the extent to which wind will be able to contribute in time has nothing to do with the availability of wind, but with the number of windmills that we can erect worldwide, in areas with sufficient wind, in order to achieve a reasonable generation price.

Competitive energy prices

Based on price levels for wind energy in 2001, it has been estimated for wind on land that world electricity demand, which is currently approximately 17 PWh (Peta = 10¹⁵) for costs under 6 €ct/kWh, can be covered entirely by wind energy, and mills can be distributed properly across the world [Hoogwijk, 2004]. 6 €ct/kWh is a price that is currently still some 50-100% above the generation price applicable using coal-fired power stations, gas-fired power stations and nuclear power stations. In the last 30 years, the price of wind energy has fallen by approximately 5% each year, particularly due to expansion. However, this development would seem to have come to an end with the advent of the latest generation of 5-MW windmills. Despite this, further price decreases in the order of magnitude of 50% are considered possible, e.g. through the upscaling of production, simpler designs (fewer parts) and through the use of new materials. It is very unlikely that prices for fossil fuels will not increase even further, given the greatly increasing demand on the world market, which means that wind energy really will become competitive in the not too distant future.