How reliable are wind turbines?

Modern wind turbines can be extremely reliable — the percentage of times many systems are available to produce power often nears 99 percent.

Another perspective is provided by comparisons with helicopters. The rotor blades must often be replaced after several hundred hours, while wind turbine blades commonly last 10 to 20 years or more. Because the wind turbines at the MEAN Wind Project at Kimball were manufactured with modern, durable, high-quality materials, their estimated life span is more than 20 years.

Wind turbine life and reliability

Driving your car an average of 50 mph would require 2,000 hours of engine run time to go 100,000 miles.
At an average in-town speed, which may actually be much lower than 50 mph, the engine may get 3,000 hours. During that time, you would need to change the oil 20 times, tune-up perhaps 10 times, change the timing belt once or twice and replace two sets of tires. Reduced to engine hours, that is about 27,000 hours of use.

At a U.S. Department of Agriculture test site in Bushland, Tex., a 40-kilowatt turbine runs about 60 percent of the time (when the wind is high enough to make power). Running 60 percent of the time with 8,760 hours in a year, 3,000 hours of operation takes about seven months. The turbine is still running after 15 years of almost continuous operation. — Contributed by Eric Eggleston