Justin Martino, Associate Editor, Power Engineering
January 31, 2014 | 3 Comments
Tulsa, OK -- Wind power capacity in the U.S. has been steadily climbing recently. Wind farms were the leading source of new power generation in the county in 2012, representing around $25 billion in investments. Although uncertainty about the federal production tax credit slowed growth in 2013, renewable portfolio standards and an overall interest in new sources of clean energy indicate wind power will continue to be an important source of generation in the U.S. for the future.
For companies looking to make an investment in wind power, there's more to do after the permits are achieved, the ground at the site is broken and construction is complete. At that point, wind farm owners need to begin looking at how to protect and get the most out of the investment they've made in renewable energy production.
Fernando Valldeperes, director of services, sales and marketing for Gamesa Corp., said wind farm operators should take a long view when seeking to protect their turbines and equipment.
"Wind turbine owners should favor medium — and long-term contracts, as O&M (operations and maintenance) services prices are stabilizing," he said. "If customers did not contract full-service maintenance contracts, they should invest in upgrades that will make the turbines more reliable and increase the energy output over the long term. Lower repair and maintenance cost on the short term is easier, but is not the best choice if operators want to improve profitability or even maintain original expected gains with the withdrawal of government incentives."
Gamesa offers a full range of solutions for wind turbine operators, including structural monitoring, turbine overhaul and life extension preventative upgrade. The company can also propose full service O&M contracts until the year 30 for Gamesa platforms for turbines from other manufacturers, Valldeperes said.
Long-term strategy is important when dealing with the fleet at it ages, he added.
"Aging fleet management not only requires an online monitoring of the drive train, but also of all the structural elements," he said. "The cost of annual audits of each turbine would offset all the benefits of extending the operational life of wind assets. This is even more true as many incentives are under scrutiny."
Valldeperes said the company's aim is to protect turbines through 30 years of operation through its life-extension service program, an ongoing monitoring and upgrade program that starts with an audit of each turbine. Gamesa then proposes a turbine-specific investment plan aimed at operating the turbine until year 30.
"Some of the preventative and corrective actions can be assumed by Gamesa through a full service contract, as not all the upgrades have to performed immediately," he said. "This full service contract until year 30 guarantees wind farm revenues and stabilized O&M. This close control of operational risks by a first-tier manufacturer is well-valued by banks, as it brings certainty."
Wind turbines have been around for some time, but the recent interest growth in the industry has led to more sophisticated turbines and an acceleration of the technology. Companies are looking to make the same advances in servicing and extending the life of the turbines as is being put in to manufacturing them.
Although Siemens continues to look at what can be done with the latest oils and greases to help lubricate and maintain equipment, Siemens' Wind Service Americas CEO Billy Watts said the company is also looking to match the sophistication of modern turbines with equally sophisticated maintenance and services and has made monitoring a major area of focus.
Siemens uses several types of monitoring, including turbine control monitoring, which focuses on rotating parts of the turbine to discover problems before they can turn into turbine failures; monitor-based monitoring, which focuses on nonrotating equipment such as temperatures and pressures; and remote diagnostic analysis, which allows the company to better troubleshoot the turbine to limit the time the turbine is down when problems occur.
The company also looks at ways to upgrade existing turbines, such as power boosts to help capture more of the wind available to the turbine. More companies are looking to get more revenue from their initial investment, and O&M services can include ways of helping the wind turbine owners achieve that goal while not having a detrimental effect on the life of the turbine, Watts said.
"We're seeing more and more customers push the limits of their turbines," he said. "We have thousands of turbines up within North America and are adding more all the time, and what we're trying to do is focus on getting the most out of them. As the customers push those limits, we need to monitor them even more closely to see what's happening when we do that, what effects we're having on the turbine and if there is something we can do ahead of time."
Service can also help dictate the design of turbines, Watts added. While owners of existing wind power projects may be looking to protect their revenue and extend the life of their investment, the long-term cost of service can be a consideration when choosing turbines for a new project — such as choosing a turbine that uses direct drive technology, which eliminates the gearbox and takes out a component that requires a lot of maintenance.
"It used to be that service was an afterthought," he said. "People were just focused on the asset itself and didn't think of the service. I think that's changing in the industry now, and people are putting the asset and the service together and looking over the lifetime they want to run the turbine. Whenever they're doing their own siting, they can look at that and ask, ‘What is the cost we're seeing on the other fleet with our gearbox?' Maybe it's more beneficial to go with a direct drive that doesn't have a gearbox."
Another aspect of protecting a turbine is ensuring the technicians providing service have the best training possible. Siemens has recently opened a new training facility in Orlando that Watts said allows the company to teach its technicians to "get to that next level of really maintaining the turbines." In addition, Siemens has engineers in its service department that can help the technicians and provide additional support.
While it may seem like common sense to ensure maintenance over the life of a turbine, Watts said it is equally important to look at the company that is providing that service. To that end, wind turbine owners should research and look at every aspect of companies that could be used for O&M.
"Look at who you're getting to service those turbines," he said. "You have to be careful. There are a lot of good companies out there, very reputable companies, but you also have to look at their safety records and where they are with their quality. We've gone behind certain turbines and seen where companies used duct tape and baling wire. You have to be careful with that and make sure you can do a thorough analysis of the service provider. You have to sit down with them and see what they can offer."