There's enough wind to power the world many times over, according to a study, but it would take a massive infrastructure investment to harness it that analysts say is not realistic.
As the world seeks to lessen its reliance on fossil fuels like coal and natural gas, renewable energy sources like wind and solar power are being developed as alternatives.
What the study showed
Contrary to some other recent studies, analysis of climate data in the Proceedings of the National Academy of Sciences indicates wind turbines could harness hundreds of terawatts of electricity, far more than is needed to power the globe, even when accounting for the interplay between the groupings of turbines in so-called "wind farms."
To reach that maximum potential, according to study author Mark Jacobson, it would require 1.5 billion massive windmills to be installed on and offshore.
That's far more than you would need to meet the world's actual energy demands, the Stanford University engineer qualified, but you would still need many millions more turbines than currently exist.
Even with substantial recent investments in wind power, "the total installed wind capacity worldwide is around 250 gigawatts," or about a hundredth of what is needed to power half the world for electricity, cooling, and everything else.
Jacobson envisions a very different future. He estimated it would take four million five-megawatt turbines - bigger than most currently in use - to power half of 2030's energy needs.
A different future
"The world today produces 70 - 80 million cars every year. We only need four million turbines once every 30 years," Jacobson reasoned, arguing it was certainly feasible.
But experts were sceptical.
"If that was the main objective of the world to do this, you could probably do it. But it's a question of how much do you spend on renewables compared to other priorities in society," said Audun Botterud, an energy researcher for the US Department of Energy's Argonne National Laboratory.
In addition to the economic investment, Botterud said the challenges of changing winds should not be underestimated.
"If you have a relatively modest amount of wind power, it's relatively easy to manage that variability and uncertainty, but as you scale it up, it becomes much more challenging," Botterud said.
"Ideally, if you have some kind of storage device that can store electricity on a large scale, you could use that to store electricity when you have a surplus," to use when the winds die down.
But "storage is still very expensive and it is kind of limited, how much storage you can build with current technologies. On top of that you, have the cost of building out transmission lines" from windy areas to where the power is needed.
University of Colorado environmental policy expert Roger Pielke agreed, saying: "Speculative science can be enlightening, but it remains far from the practical world of energy systems."
(Sapa, September 2012)
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