, Gloucester, MA

March 30, 2013

Wind Turbines 101

By Gail McCarthy
Staff Writer

---- — During the Gloucester Lyceum’s wind energy panel discussion Thursday, residents submitted questions to the panel. They included:

Q: Why are one or more turbines shut down on certain days? A: The start up of any major piece of equipment is when you find issues that come up in the first months. This is normal, and they are shut down while the issue is addressed.

Q: What would have been the cost of the risk if the city had done the project? A: Each turbine is roughly $5 million, so $10 million.

Q: Where do you store excess electricity? A: It’s not put in a giant battery. It doesn’t get stored anywhere. Both projects are connected to the electrical distribution system and there is enough on-site demand, or it goes into the grid.

Q: What kind of safety measures are there in case of gale-force winds? A: They are designed to handle up to 56 mph, When the wind speed is higher, the blades shut off and pitch away from the winds. They will return to operation when the winds are less than 56 m.p.h. There were also fall-zone studies to make sure the locations took into consideration any catastrophic scenarios.

Q: How much wind is needed to generate power? A: It takes about 3 meter per second, or about 7 mph.

Generally prior to reaching 7 mph, the blades are in some form of rotation so often the blades are not starting from a dead stop and are waiting for the wind to pick up.

Q: Why are there lights — and why are they on and off? A: They are required by FAA regulations. They are light sensitive so when the sun comes out, they turn off, and vice versa.

Gail McCarthy can be reached at 978-283-7000, x3445, or at