Turbine testing leaves questions unanswered
By LOUISE BARTEAU | March 09, 2013 | www.southcoasttoday.com
By LOUISE BARTEAU | March 09, 2013 | www.southcoasttoday.com
At 11:30 p.m., on the night of Oct. 14, I met Laurel Carlson of the state Department of Environmental Protection and Ryan Callahan of Tech Environmental at the Senior Center for the purpose of sound sampling the Fairhaven turbines. The wind was blowing from the south-southwest.
We started at Peirce’s Point. Ms. Carlson and Mr. Callahan were both taking measurements with expensive sound samplers. I was observing and recording Laurel’s numbers while taking notes. At the time, the wind speed was reported by Mr. Callahan to be 10 meters per second at the hub.
In addition to taking samples for Fairhaven Wind, Mr. Callahan was also in charge of operating the turbine that night.
The process Ms. Carlson followed was to record sound levels by decibel readings at 5-second intervals for five minutes at a time. She recorded three samples with the turbines on and three samples with the turbines off for the purpose of finding the difference between the two sets of numbers. She gathered the data at four or five locations each time she sampled. She sampled based on the locations with the most Board of Health complaints last May and June, when the DEP met with Fairhaven Wind to develop the testing protocol.
At Peirce’s Point I observed decibel readings from 48 to 55 with the turbines on. The low numbers with the turbines off began at 41.
When we moved to Shawmut Avenue next, the low number with the turbines off was 38. When the turbine were turned back on, I observed that the south turbine was rotating more slowly than the north turbine and I mentioned it at the time, and I recorded it in my notes. With the turbines on, the impact reading that I noted was 47.
These numbers by themselves don’t mean much. The process involved taking many readings over time. Ms. Carlson took multiple samples and recorded interference from airplanes and cars that skew the numbers.
Another factor that night was the wind blowing through the leaves in the trees. Investigative acousticians work very hard to minimize the impact of the wind on the microphone, however, the DEP does not address wind at the microphone, which can affect the readings and raise ambient readings.
In my notes of that night I wrote the following, “South turbine slower, not as noisy!”
I mentioned it to Ms. Carlson, who said in reply, “they are often asynchonous, I see that from the Bay while sailing.”
Months later, a friend was Googling the Fairhaven turbines and found the powerdash link, which he sent to me. When we looked at the night of Oct. 14-15, we saw that despite above average wind speeds, the south turbine was not producing power during the hours of the testing. But immediately following the testing the south turbine was producing significant power.
I wrote to confirm this finding with Ms. Carlson, who wrote in an email to me dated Jan. 25 that she was unaware of any power problems on the night of Oct. 14-15. I asked her to double-check the power data. When I had not heard back in several weeks I lodged a formal complaint with the DEP.
I also sent copies of the complaint to the Fairhaven Board of Health and the Board of Selectmen, as well as to The Standard-Times and to the neighbors whose homes are part of the testing process. This resulted in a WLNE-TV news story.
Fairhaven Wind has written to the DEP in response, claiming operator error. Apparently this explanation has been accepted by the DEP, as explained to me in a letter from Martin Suuberg, deputy director of the DEP.
The DEP has closed its investigation without speaking to me about my findings. Peter DeTerra , chairman of the Fairhaven Board of Health, has declined to put me on the agenda to explain my findings. Selectmen Chairman Brian Bowcock has also refused my request to be put on the agenda to explain my findings.
Case closed?
There are two important questions that have not been answered to my satisfaction:
Why didn’t the DEP know about this until a citizen watchdog pointed it out? And what will they do to prevent the power being adjusted to half-power in the re-testing? Because, while a full turn-off is easy to detect, it is much harder to detect it when the power is turned down, but not off.
Louise Barteau lives in Fairhaven.
URL to article: https://www.wind-watch.org/news/2013/03/09/turbine-testing-leaves-questions-unanswered/