Wind turbine efficiency drops as much as 20 percent a year, industry says

While the wind industry likes to boast of a 30% efficiency rate (Algonquin Power claimed 40% for 20 years in its prospectus for the Amherst Island project) the truth is somewhat different.

In fact, says an industry insider in the current issue of North American Clean Energy, efficiency decline is a major concern for the wind power industry, and it is well known that “erosion” of the turbine blades alone can lead to a 20-percent drop in annual power production.

The author of the article works with 3M and his intent was to flog the company’s products to reduce blade erosion.

“The heart of the issue is the fact that wind blades come into contact with rain, hail, salt spray and other debris in the air at rotation speeds of up to 250 mph, leading to erosion in the form of pitting, gouging, and delamination of the edge of the blade,” writes Santhosh Chandrabalan. “this erosion not only compromises the integrity of the blade, but also impacts its aerodynamic efficiency, causing a significant loss in AEP [annual energy production].”

 

 

 

Comments

Bill Palmer
Reply

Dirty or eroded blades also increase the wind turbine sound power level (SPL) by from 3 to 5 dB. If all turbines in an array increase by 3 dB(A) then the sound pressure level (also SPL) at a receptor also increases by 3 dB. The residence rated at 40 dBA becomes 43 dBA.

wgulden
Reply

Notice the “30% efficiency rate”? I suspect they are talking about capacity factor, not efficiency. Capacity factor is a function of efficiency (sorta times wind speed cubed), but efficiency is not a function of capacity factor. Harrison, Hughes and I (among others) have all found significant decreases in efficiency/capacity factor in wind turbines over time. Certainly Ontario’s turbines suffer from it. Unfortunately, now that the IESO is dispatching wind production it is difficult/impossible to calculate by how much.

Leave a comment

name*

email* (not published)

website