How tall is a wind turbine? The rotor of the latest GE wind turbine sweeps a circle the size of the London Eye, the giant Ferris Wheel that looms across the River Thames over the Big Ben. In fact, the turbine is so large that engineers had to find a way to compensate for the difference in wind speed between the top and the bottom blade. “When the top tip is 650 feet high, the bottom blade is 25 stories below,” says Vic Abate, vice president of GE’s renewable energy business. “The pitch of the blades keeps changing as they rotate. Think about it like sails on a sailboat. The fuel is free and you take this fuel and you concentrate it so that machine can produce more power more often.”
Blade of Glory: This giant blade, 57.8 meters long (189 feet), will be part of the new turbine’s rotor.
But the new turbine, which GE calls 2.5-120 (that’s for 2.5 megawatts in output and 120 meters in rotor diameter), is not just big. It’s also got a brain that can be plugged into the Industrial Internet, the global data network that knits together machines, people, and powerful analytics. “The turbine is the sensor, and we have turbines talking to turbines,” Abate says. “We are able to optimize the power output of a wind farm and make it more predictable and reliable.” That’s exactly what utilities and grid operators want.
Like a flock of birds, the turbines can talk to other turbines and even other wind farms, and compare data about wind speed and direction over a large geographical area. “We have advanced forecasting algorithms that give us power output predictions based on the data they are receiving,” Abate says. “With this technology you are able to say, I am going to give you 70 megawatts over the next 15 minutes and with 99 percent accuracy.”
Abate’s team is using engineers who worked on the Joint Strike Fighter engine to calibrate the algorithms with the machinery. “The simplest way to think of that is like anti-lock brakes,” he says. “They allow you to stop in controlled shorter distance. It’s the same thing. By controlling how we slow these turbines in a controlled fashion, we minimize the loads, which enables us to get the bigger rotor.”
The turbines are also connected to batteries that can mop up excess power and release it when wind slows down. “It’s predictable power,” Abate says. “When you get little more wind than you need, you can store the power in the batteries. When the wind comes in a little short than you thought, you can use the batteries. It gives you a stable output. With just a small amount of storage, I can integrate hundreds of megawatts of wind power into the grid seamlessly.”
Engineers like Keith Longtin, general manager for wind products at GE, say that a wind farm populated with the new turbines will generate 150,000 data points for analysis every second. The data feed algorithms that allow the turbines to operate at a record 45 percent of its full capacity factor over a year in 7 meters per second (about 15 miles per hour) wind regimes. “This means that the technology is able to take wind farms, which were traditionally in high wind locations and away from where people lived, to more sites,” Longtin says.
Abate says that as a result of the turbines’ size, and their brains, the 2.5-120 turbines provide a 25 percent increase in efficiency and a 15 percent boost in power output compared to GE’s current model.
GE has already successfully demonstrated the integration of wind power and batteries at its facility in California. The company will build the first prototype of the 2.5-120 turbine in the Netherlands next month.
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