March 27, 2008
Colorado, Wyoming

Wind turbine parts unexpectedly failing

Some components on Vestas Wind Systems-manufactured wind turbines at Platte River Power Authority’s Medicine Bow Wind Project are failing more than 15 years earlier than expected, according to PRPA.

Since the Medicine Bow, which is in southern Wyoming, went online in 1998, 30 major outages have occurred on the wind farm’s nine turbines due to component failure, said John Bleem, PRPA division manager.

Although outages vary, Bleem said repairs have led to turbines being down for as long as three months and costing as much as $100,000 – paid for by Vestas under its manufacturer warranty set to expire in 2011.

Vestas recently opened a turbine blade production facility in Windsor. The parts referenced by Bleem were not constructed at the Windsor plant.

Because the wind blows intermittently, it’s unknown how much power PRPA, which supplies power to Fort Collins, Loveland, Long-mont and Estes Park, has lost during the outages.

“When that warranty expires, then it’s treated just like a warranty on a car where we will be responsible for the cost of repairs,” Bleem said. “We are negotiating service contracts; and those costs have gone up for repairs and maintenance on the machines, and it will continue to go up with labor rates and parts costs.”

That’s one reason PRPA officials are struggling to find the right blend of building new wind projects to create renewable energy or buying into other projects, often out of state, that create energy never used by Fort Collins residents.

The high cost of wind

Historically, PRPA has bolstered its renewable portfolio through the purchase of renewable energy credits, or RECs, that allow it to invest in wind farms owned by others who pay for maintenance and repairs. PRPA can purchase credits that help build infrastructure, credits for the power a wind farm generates, or both.

Although PRPA receives a majority of its renewable energy through RECs, its homegrown Medicine Bow project has been far more costly despite producing less energy.

“We spend two-thirds of our renewable budget on energy and one-third on purchasing RECs,” Bleem said. “About 80 percent of our portfolio supply comes from RECs, and 20 percent is coming from energy. So what that tells you is that renewable energy is much more expensive than purchasing RECs.”

Nearly five to six times more expensive.

“We pay about 1 cent (per kilowatt-hour) for RECs, and we pay about 5 to 6 cents (per kilowatt-hour) for the wind energy we produce ourselves,” Bleem said.

Despite getting a bigger bang for its buck through purchasing RECs, PRPA has been working toward the production of new wind farms in the past year, said Brian Moeck, PRPA general manager.

In a presentation to the Fort Collins City Council on Tuesday night, Moeck said the PRPA board has been paying close attention to pending carbon legislation at the federal level that could create a carbon tax or a cap-and-trade program. If a carbon tax were created, it would become more cost-effective for PRPA to build its own wind projects.

“The policy changed because the board could see the (pending) legislation and depending on how that works out it could affect us very much,” Moeck said.

Mitigating repair costs

PRPA has been negotiating with Vestas to extend its Medicine Bow warranty beyond 2011 with some success, but the final result will likely leave the power authority paying a higher premium and more for repairs to its nine turbines.

Bleem declined to say what those rates would be, citing a confidentiality clause PRPA has with Vestas.

Vestas declined comment to the Coloradoan Wednesday.

“There is regular scheduled maintenance,” Bleem said. “Lubrication is the major thing as well as some minor components that need replacement like filters, but the biggest concern is unscheduled outages. The unscheduled repairs are what have us concerned the most.”

A lot has changed in wind turbine technology since 1999, when a majority of the Medicine Bow turbines were built and installed, and repairs could be less frequent with new projects, PRPA officials said.

“We have been getting (proposals) in from companies to build our next project and the quoted prices are higher than we expected,” Bleem said. “We work to serve our cities though; and if they want us to move in a certain direction, then we do.”

By Jason Kosena

The Coloradoan

27 March 2008


URL to article:  https://www.wind-watch.org/news/2008/03/27/prpawind-turbine-parts-breaking-too-early/