US-China Researchers Claim Wind Speeds, And Wind Power-Generation Potential, Have Declined

Researchers in China and the United States have found evidence that wind speeds, and the potential power generation such speeds allow, have been decreasing in the Northern Hemisphere since 1979. The findings are published in the January 2019 edition of Energy.

Using data collected from 1979 to 2016 and gathered from “over 1000 weather stations worldwide,” the study claims that “surface wind speeds were decreasing in the past four decades over most regions in the Northern Hemisphere, including North America, Europe and Asia.”

The report further states that the decline in wind speeds is not only at the surface.

“In conjunction with decreasing surface wind speeds, the wind power potential at the typical height of a commercial wind turbine was also declining over the past decades for most regions in the Northern Hemisphere. Approximately 30%, 50% and 80% of the stations lost over 30% of the wind power potential since 1979 in North America, Europe and Asia, respectively,” the report said.

However, some analysts believe drawing hasty conclusions from the study would be a mistake.

In an article about the study at GreenTechMedia (GTM), Shashi Barla, a senior analyst, said that “these kinds of studies need to be taken with a pinch of salt, with all due respect to them. Maybe it’s true, but would it have an impact on the [wind power] industry? I don’t know.”

GTM also reports that Barla said any decline in “wind resource might be canceled out by improvements to turbine technology.”

The Chinese Academy of Sciences (CAS), which worked on the study, said in a press release that “renewable energy contributes more than 19% to the global final energy consumption. Of all the renewable energy sources, wind is one of the key players in terms of installed electricity generating capacity, only exceeded by hydropower.”

CAS also said that wind “energy is a natural resource characterized by instability.”

Though it is not known what impact the study’s findings might have on the wind power-generation industry, Geoffrey Taunton-Collins, described as a “senior analyst at specialist renewable energy insurance provider GCube,” told GTM that the study “should be of particular concern to operational wind farms whose financials are based on resource estimates which don’t factor in lower future wind speeds [… but] project owners would do well to be cautious about the headlines generated by studies of this kind.” 

According to GTM, analysts further note that decreases in wind speed may be the result of “land use” and “surface cover” changes, such as expanding cities or increases in regional vegetation. They also note that a 2017 study suggested increased carbon-dioxide, an alleged culprit in global warming, may also slow wind speeds.

The collaborative study was published this month and was done by researchers at the Institute of Atmospheric Physics at CAS in Beijing, and at Purdue University, in West Lafayette, IN. GTM said the researchers are “now conducting a follow-up study to investigate possible reasons for the drop” in wind speeds.