Report: Willmar’s wind turbines work well

WILLMAR - The state of Willmar Municipal Utilities’ two wind turbines is good, according to a report given Monday to the Willmar Municipal Utilities Commission.
Electrical production from May 2014 to April 2015 has increased from a low of 216,998 kilowatts in August 2014, which was
44 percent of projections, to 1,021,111 kilowatts in April 2015, which was 88 percent of projections, said Jon Folkedahl, power production supervisor.
One factor that led to lower production between May and July 2014 was the nose cone repair that was required in June 20 14 after the nose cone fell off of one of the turbines.
The utility constructed the two turbines on land just north of Willmar Senior High School and the turbines have been producing electricity since July 2009.
A date to remember, said Folkedahl, was September 2014 when the warranties with turbine manufacturer DeWind expired and Willmar Utilities essentially took charge of maintenance at that point.
“Not to give us excess credit, but things have been going much better since that date,’’ he said. Folkedahl explained there have been some personnel changes at DeWind and DeWind technicians have been much more responsive and much more capable than in the past.
“So it’s been going pretty well,’’ he said, noting that April 2015 production exceeded a million kilowatt-hours.
DeWind technicians were in Willmar for eight days in April to perform semi-annual maintenance. The cost was $23,129. Folkedahl said DeWind technicians will also perform scheduled maintenance in the fall.
Folkedahl presented a copy of a typical written report that DeWind technicians file every day that they are in Willmar for turbine service.
“We have records since last September of every visit that these technicians have made,’’ Folkedahl said. “We send our own technicians up the wind towers once a week, just to do general inspections to make sure there aren’t any serious leaks or problems that they can observe in the turbines. The turbines are complex machines. But we try to keep them as neat and clean as possible.’’
Folkedahl’s report included a photo of a cooler in the south tower that had become plugged with fine dust or dirt and had caused unexpected, intermittent overheating problems earlier this spring. The cooler is located behind an opening on the side of the turbine and is exposed to outside air.
The cooler, which resembles a radiator, was cleaned during maintenance. Folkedahl said nobody has a good explanation of why the the cooler was filled with dirt.
“We must have had a dust storm. That’s all I can say. That’s the first time we’ve seen that issue,’’ he said.
Folkedahl was asked if DeWind would continue to provide scheduled maintenance or if utility staff could handle some of it.
Folkedahl said Willmar is receiving service from DeWind’s most experienced technicians. He said lead technician Chad Sander has been with the company for approximately 10 years and is responsible on a daily basis for 97 turbines in Oklahoma and Texas.
Folkedahl said he foresees that Willmar will continue to employ DeWind for some time. But he did add that DeWind technicians are able to guide Willmar staff by telephone through many activities. One of those was replacement of a failed rotor brake sensor.
“Our guys were able to remove the 20-foot-long cable and sensor and thread a new one back in and get it plugged into the right spot on the circuit panel,’’ Folkedahl said. “Typically, DeWind doesn’t even charge us for that. It’s part of their monthly monitoring activity.’’
In other business, the commission was told by operations director John Harren that the annual power plant overhaul has gone well so far and is mostly complete.
“It’s been extremely busy,’’ he said. “But we’ve gotten a lot of important maintenance activities completed.’’