When a wind turbine malfunctions and the problem can’t be fixed remotely, General Electric technicians have traditionally had two options.
If the malfunction occurred in an easily accessible part of the turbine’s gearbox, they could climb the approximately 240 feet up the turbine and repair it mid-air.
Oftentimes, though, a mechanical failure requires taking apart the gearbox, if not entirely, then at least partially. But that part of the turbine weighs a whopping 36,000 pounds and requires an immense crane to get it down to the ground, where it can be taken apart, repaired or replaced.
As a large player in the wind industry, GE began brainstorming in 2012 on ways to avoid the entire crane component of turbine repair. If its technicians could do repair work entirely “uptower” (at the top of the turbine), they could avoid tacking on the expense of a crane to their customers’ bills.
“For a large crane, you’re looking at any-
where from $100,000 to $250,000 to get that gearbox down,” said Greg Thomas, a GE engineer. “That’s a lot of money we can save for the customer.”
On Wednesday, GE officially opened its new Global Wind Turbine Drivetrain Repair Innovation Lab at the site of its existing Power Generation Repair Technology Center on Anderson Drive in Albany. Inside the lab are gearboxes from seven different GE turbines, a 20-ton crane and advanced machining tools that allow for robotic welding and rapid prototyping with 3D printers. Here, Thomas and fellow GE engineer Rick Ohl will simulate on the ground ways to solve mechanical issues uptower. This will allow GE to either conduct repairs entirely uptower or conduct most repairs uptower and bring in a smaller crane for the rest of the work.
“No matter what, you’re going to see a huge decrease in cost, and that’s really our goal,” said Thomas.
GE spent $500,000 to convert a storage warehouse from the nearby power generation repair center into the new simulation lab. Renovations began in the spring of 2013. On Wednesday the finished lab was unveiled to employees who work at GE’s renewable energy headquarters in Schenectady.
The new lab won’t just be Thomas and Ohl, though. They will work closely with GE engineers and technicians in Schenectady and Niskayuna to develop new technologies to apply to field service repairs and to improve serviceability.
“This is the first facility of its kind dedicated to developing repair technologies and capabilities that reduce the life cycle cost of wind turbines,” said Andy Holt, general manager of Wind Projects and Services for GE Power & Water’s Renewable Energy division. “Albany was an ideal location for the facility with its close proximity to GE’s renewable energy headquarters, the GE Energy Learning Center, as well as the existing [repair center]. It is uniquely positioned for collaboration with the field, design engineering, training and product service teams.”
GE got into the wind business in 2000 after buying Enron’s wind turbine fleet. At the time, turbines were faulting more than once a day. Today, that number is down to 4.8 times a month. About half of those problems are diagnostic issues that can be fixed from GE’s remote operations centers in Schenectady, Salisbury, N.C., and Shanghai, China. The rest require technicians to climb a turbine on-site to find the issue or complete the repair.
Inside the simulation lab Wednesday, Thomas pointed out one of the mechanical issues that can occur on the turbines.
“This component right here is a broken tooth,” he said, pointing to a rotational piece of the gearbox that was missing a chunk of metal. “This is caused by age or any number of things, really. But a big chunk has been broken off, and that’s not something you can fix remotely, obviously.”
Mechanical repairs — depending on the type of repair and its location within the gearbox — can range anywhere from $20,000 to $100,000, said GE Wind Services sales leader Jeff Wiener. Wear and tear over the years can require changing out bearings, slip rings and rotors, or just routine maintenance. A high-speed bearing would cost just $20,000 to repair, he said, because it’s small and accessible and can therefore be done entirely uptower.
What the new lab will do is find ways to repair or replace those pieces of the gearbox that aren’t as accessible, so that the entire gearbox doesn’t have to be taken apart on the ground.
“The industry needs uptower repair to really reduce the cost and save both the owners and consumers money,” said Wiener. “Every turbine owner and wind farm operator is interested in it because if you can do it without the crane, you just saved yourself a lot of money. So that’s why we’re trying to be on the leading edge with this new facility.”