Timeline:
February 1, 2011: L.M. Miller, F. Gans, and A. Kleidon of Germany’s Max Planck Institute for Biogeochemistry publish a paper in the open access journal Earth System Dynamics casting doubts on the possibility of harvesting massive amounts of wind energy to meet global electricity needs and suggesting that doing so could have "some" effects similar to doubling atmospheric carbon dioxide (CO2).
March 10, 2011: Kleidon submits a paper to Philosophical Transactions of the Royal Society on his work.
March 30, 2011: The U.K. science magazine New Scientist runs an article on Kleidon’s work entitled, remarkably, "Wind and wave energies are not renewable after all." (Following the criticism detailed below, the article’s headline is later changed to "Wind farm and wave could affect Earth’s energy balance.")
April 4, 2011: The blog Climate Progress carries an article by its editor, Joe Romm, sharply criticizing the New Scientist piece ("Yes, wind and wave power are renewable; New Scientist pulls a Charlie Sheen"). Romm says in part, "There is no evidence whatsoever that [dramatically increasing wind power use, to 20 times current levels] would cause any significant harmful global impacts, let alone ones that are even close to the multiple catastrophes that await us if we double CO2 concentrations … " and refers to a seven-page critique of the Miller-Gans-Kleidon work written by Mark Jacobson of Stanford and Cristina Archer of California State University-Chico.
Jacobson and Archer’s criticism is direct: "We believe the wind power resources from MGK10, estimated as 17]38 TW over land, are low by a factor of up to four due to the unphysical nature of MGK10’s calculations and the fact that such calculations are not comparable with data]derived wind resources. Further, even if MGK10’s wind resources were correct and their scenario realistic, the climate consequences stated by the authors are overestimated by a factor of at least 50]100. In addition, when their scenario is put in a realistic context whereby wind energy replaces thermal power plants, the effects of wind turbines can only be no net change or a reduction in internal energy added to the atmosphere and a significant reduction in other forcings due to the elimination of greenhouse gases (GHGs) and black carbon (BC) from such power plants."
A noteworthy weakness of the Miller-Gans-Kleidon approach, Jacobson and Archer add, is that while massively increasing use of wind power (from today’s 197,000 MW installed worldwide to between 17,000,000 and 38,000,000 MW) would produce heat (some heat is produced when the kinetic energy of the wind is converted into electricity), that heat would be offset by eliminating fossil fuel combustion: "Second, their scenario of merely adding 17]38 TW of wind is an irrelevant scenario, since it ignores the fact that wind would replace existing combustion technologies, which add direct heat to the atmosphere along with CO2, other GHGs [greenhouse gases], and BC [black carbon]. The 0.033]0.074 [watts per square meter] of heat from [wind] turbines displaces at least the equivalent heat from thermal power plants (e.g., Santa Maria and Jacobson, 2009), but wind turbines simultaneously eliminate nearly all CO2, other GHGs, and BC from such power plants. Thus, replacing thermal plants with wind turbines serves only to eliminate nearly 100% of CO2, other GHGs, and BC without any additional heat added to the atmosphere. MGK10 do not take into account the waste heat from traditional power plants."
April 7, 2011: AWEA Manager of Transmission Policy Michael Goggin, in an article published here ("Further analysis of bizarre New Scientist Article on wind power"), identifies some additional weaknesses in the Miller-Gans-Kleidon work. Regarding the heat issue, Goggin commented: "All of their model runs indicate that a 100-fold increase in wind energy production would cause zero change in surface temperatures. A 1,000-fold increase wind energy output does cause a small, 1-degree-C increase in surface temperature, but that is not a real climate forcing, but rather just a localized movement of energy from the upper atmosphere down to the surface as the turbine catches less dense higher level air and it releases heat as it adiabatically expands. Again, no energy is being produced from that, and the earth’s energy balance is not being changed nor the climate forced; this is just a localized phenomenon downwind of a turbine that should normalize as the atmosphere mixes. More importantly, it only occurs at wind penetrations 1,000 times higher than we have today."
July 6, 2011: More than two months after Climate Progress has essentially thrown the kitchen sink at New Scientist and helpfully provided references supporting its views, Chris Rhodes of the Forbes Energy Source blog runs an article on the February 1, 2011, Miller-Gans-Kleidon submission. Strangely, he does not mention either the Climate Progress article or the Jacobson-Archer response–the Miller-Gans-Kleidon work is presented as if it were brand new. This is NRS, folks–Not Rocket Science. If you Google "wind kleidon," the Climate Progress article is the third one listed, and any serious report on the Miller-Gans-Kleidon work needs to mention that it has been severely criticized.
Is this the end of the story? Probably not. The notion that massive use of wind farm generation will cause climate-change-like effects has been kicking around in unpublished and published work for a number of years, and the anti-wind turbines echo chamber is always looking for a good story, regardless of how full of scientific holes it is or how many times it has been refuted. Stay tuned.
By Tom Gray, www.awea.org/blog/
