There is enough wind to easily meet all of the world’s energy needs, according to new US research.
Writing in the peer-reviewed academic journal Nature Climate Change, Kate Marvel of Lawrence Livermore National Laboratory along with Ben Kravitz and Ken Caldeira of the Carnegie Institute estimate that more than 400 TW of power could be extracted from surface winds.
Currently, the world uses around 18 TW of power, so surface wind alone – which is harnessed by both on- and offshore turbines – could meet future needs 20 times over.
The research also looked at high-altitude winds, which could be harnessed in the future via technology bringing together turbines and kites. These winds could provide some 1800 TW of power – 100 times current demand.
But turbines create drag, or resistance, which tends to slow winds down. Ultimately, at some theoretical point, a maximum number of turbines is reached beyond which the wind is slowed so much that additional turbines would not generate any more power.
It is this maximum level of wind power extraction that the researchers calculate, which stands at some four million 5 MW turbines.
But there could be climate effects of extracting so much wind energy. The research finds that the climate effects of extracting wind energy at the current level of global demand would only be small if turbines are well distributed and not clustered in just a few regions.
At the current level of global energy demand, wind turbines could affect surface temperatures by around 0.1°C and precipitation by 1%.
“Looking at the big picture, it is more likely that economic, technological or political factors will determine the growth of wind power around the world, rather than geophysical limitations,” says Caldeira.
For further information:
Scottish Government gives go ahead for Stornoway wind farm (11-Sept)
Developers submit proposal for 1.5 GW Moray Firth wind projects (5-Sept)
US wind energy blows through 50 GW but uncertainty ahead (14-Aug)
UK leads 50% boost in European offshore wind capacity (23-Jul)
Article source: http://www.energyefficiencynews.com/i/5366/