A social media post claims a leading study found wind turbines create more global warming than the fossil fuel-powered energy sources they replace.
But the claim is false. The 2018 study, conducted by two then Havard University researchers, found turbines create localised warming due to the spinning blades mixing the air near the ground and above while extracting from the atmosphere’s motion.
While this has a temporary impact on local temperatures, it has nothing to do with global warming which is the long-term increase in the earth’s temperature due to human activity, primarily burning fossil fuels.
The post on the Australian Climate Sceptics blog, reads: “Harvard study finds that wind turbines create MORE global warming than the fossil fuels they eliminate – and the same is true for scooters and electric cars.”
Much of the blog’s information comes from a 2019 post on the Citizens News website which reported on the 2018 study.
Professor David Keith, from Harvard University, and Dr Lee Miller, then of Harvard but now a scientist at Seattle’s Pacific Northwest National Laboratory, were behind the research that looked at the environmental impacts of wind power.
Their paper calculated how many turbines would be needed to meet 100 per cent of the US’s electricity generation. It then looked at the impact of these turbines on the local climate, calculating a 0.24C increase in the surface temperature where they were located.
The authors noted this was an unlikely and extreme scenario given there would be a mix of energy production.
The paper explains the warming is created by the turbines mixing the air near the ground and then higher up, while also extracting from the atmosphere’s motion.
The researchers found the localised warming impact of the turbines (0.24C) would be larger than the temperature effect of reduced emissions for up to the first century of their operation.
But Prof Keith and Dr Miller told AAP FactCheck their findings have nothing to do with global warming.
“Our group and many others have found that wind turbines cause climate changes and that these changes may be significant,” Prof Keith said in an email. “These changes are not the same as warming from greenhouse gases so it’s misleading to call them global warming.”
Dr Miller said: “Global warming is caused by changing greenhouse gas concentrations. The physical processes causing the temperatures to change are different.”
The paper also features a section warning of any comparison with global warming.
“Wind power does not add more heat to the atmosphere. Wind turbines redistribute heat by mixing and alter large-scale flows both which can change climate,” it states.
The paper further makes the distinction with global warming, stating that several studies found wind power deployment could even make local temperatures cooler, such as in the Arctic.
“(Wind turbines) simply redistribute heat in the atmosphere, which is already naturally present, so that more heat is present near the surface,” he said.
“This contrasts with the effects of greenhouse gases such as carbon dioxide; increasing carbon dioxide causes a real increase in the energy (and hence temperature) content of the atmosphere.”
Prof Moobs added: “The effect of greenhouse gases is cumulative and will last for many thousands of years (essentially indefinitely in policy terms) whereas the effects of wind farms would stop immediately if they were turned off.”
The paper’s authors said the findings were important for those making “strategic decisions about decarbonising the energy system“.
However, they make clear their assessment of wind power’s climate benefits in the paper’s conclusion.
“Wind beats fossil fuels under any reasonable measure of long-term environmental impacts per unit of energy generated.”
The claim that a Harvard study found wind turbines create more global warming than the fossil fuels they eliminate is false. The 2018 paper instead found wind turbines create localised, temporary warming.
This impact on the climate has nothing to do with global warming which is the long-term increase in the earth’s temperatures, primarily as a result of burning fossil fuels.
False – The claim is inaccurate.