I came across an article on New Scientist the other day that raises concerns that the increased use of wind and/ or wave resourced energy will have negative impacts on the atmosphere, apparently increasing radiative forcings, and retarding ecosystemic services. Following this to the source article in the journal Earth System Dynamics shows a thought-provoking take on the claimed sustainability of wind and wave energy resources.

The New Scientist's article reports that although "the winds will not die, sucking that much energy out of the atmosphere in Kleidon's model changed precipitation, turbulence and the amount of solar radiation reaching the Earth's surface. The magnitude of the changes was comparable to the changes to the climate caused by doubling atmospheric concentrations of carbon dioxide".

"'Large-scale exploitation of wind energy will inevitably leave an imprint in the atmosphere'," says Kleidon. "'Because we use so much free energy, and more every year, we'll deplete the reservoir of energy.'" He says this would probably show up first in wind farms themselves, where the gains expected from massive facilities just won't pan out as the energy of the Earth system is depleted.

Using a model of global circulation, Kleidon found that the amount of energy which we can expect to harness from the wind is reduced by a factor of 100 if you take into account the depletion of free energy by wind farms. It remains theoretically possible to extract up to 70 TW globally, but doing so would have serious consequences.

Although the winds will not die, sucking that much energy out of the atmosphere in Kleidon's model changed precipitation, turbulence and the amount of solar radiation reaching the Earth's surface. The magnitude of the changes was comparable to the changes to the climate caused by doubling atmospheric concentrations of carbon dioxide" (Earth System Dynamics, DOI: 10.5194/esd-2-1-2011).

The original paper is available from the Earth System Dynamics journal site:  http://www.earth-syst-dynam.net/2/1/2011/esd-2-1-2011.pdf along with some discussion among reviewers and the authors which makes interesting (but v. technical) reading:  http://www.earth-syst-dynam-discuss.net/1/169/2010/esdd-1-169-2010-discussion.html

Read the article on-line at the web address below, and note New Scientist's recent (on-line) update:
"UPDATE, April 6: This article has elicited a considerable amount of interest, and some criticism. We always welcome discussions of the stories we publish. Some readers felt the original headline (Wind and wave energies are not renewable after all) was misleading, so to address these concerns we have changed it. We have also been made aware of a wider debate about Kleidon's research that we did not address in the original article: we will continue to follow this issue and report back on what we find."

In promoting what we currently understand as renewable and safe energies, it behooves us to ensure that the impacts of treatment are not more problematic than the symptoms. Articles of such a nature endorse the value of advocating both energy use reduction - powering down - as well as sourcing energy production renewably.