IANS | 10 Sep, 2012
With oil, gas and coal depleting fast, US scientists say that available wind power is enough to fuel all of the world's energy demands. The atmospheric wind turbines in high altitude areas generate even more power than ground-and ocean-based units.
Near-surface winds could provide more than 20 times global power demand and wind turbines on kites could potentially capture 100 times the current global power demand.
Surface winds are those that can be accessed by turbines supported by towers on land or rising out of the sea. High-altitude winds are those that can be accessed by technology merging turbines and kites, the journal Nature Climate Change reports.
New research from Carnegie Institute's Ken Caldeira examines the limits of the amount of power that could be harvested from winds, as well as the effects high-altitude wind power could have on the climate as a whole, according to a Carnegie statement.
"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," Caldeira said.
Led by Kate Marvel of Lawrence Livermore National Lab, who began this research at Carnegie, the team used models to quantify the amount of power that could be generated from both surface and atmospheric winds. The study looked only at the geophysical limitations of these techniques, not technical or economic factors.
Using models, the team was able to determine that more than 400 terrawatts (TW) of power could be extracted from surface winds and more than 1,800 TW could be generated by winds extracted throughout the atmosphere. Today, civilization uses about 18 TW of power.
As the number of wind turbines increase, the amount of energy that is extracted increases. But at some point, the winds would be slowed so much that adding more turbines will not generate more electricity. This study focused on finding the point at which energy extraction is highest.
At maximum levels of power extraction, there would be substantial climate effects to wind harvesting. But the study found that the climate effects of extracting wind energy at the level of current global demand would be small, as long as the turbines were spread out and not clustered in just a few regions.
