310 likes | 406 Views
COMMUNITY REACTIONS and CRITERIA: WIND TURBINE NOISE. Robert W. Rand, INCE Rand Acoustics Brunswick, Maine. Code of Massachusetts Regulations (Title 310, Section 7.10, amended September 1, 1972) Policy
E N D
COMMUNITY REACTIONS and CRITERIA:WIND TURBINE NOISE Robert W. Rand, INCE Rand Acoustics Brunswick, Maine Rand Acoustics - Shelburne Falls, March 3, 2012
Code of Massachusetts Regulations (Title 310, Section 7.10, amended September 1, 1972) Policy A noise source will be considered to be violating the Department’s noise regulation (310 CMR 7.10) if the source: 1. Increases the broadband sound level by more than 10 dB(A) above ambient, or 2. Produce a “pure tone” condition – when any octave band center frequency sound pressure level exceeds the two adjacent center frequency sound pressure levels by 3 decibels or more. These criteria are measured both at the property line and at the nearest inhabited residence. “Ambient” is defined as the background A-weighted sound level that is exceeded 90% of the time, measured during equipment operating hours. “Ambient” may also be established by other means with consent of the Department. Rand Acoustics - Shelburne Falls, March 3, 2012
MassCEC Acoustic Study Methodology for Wind Turbine Projects Issued: December 9, 2011 The methodology is intended to be compatible with the Massachusetts Department of Environmental Protection’s (MassDEP) noise regulation. However, the methodology is not intended in any way to alter, substitute, create, or enforce any policy or regulation that is in force or may be developed by MassDEP or any other regulatory agency. While this methodology is intended to assist project developers anticipate whether a project will comply with MassDEP’s noise regulation, following this methodology in itself does not constitute or guarantee compliance with MassDEP’s noise regulation. MassCEC assumes no responsibility or liability arising from or related to a project’s failure to meet MassDEP’s noise regulation. While use of this methodology is required for MassCEC acoustic studies initiated after the issue date of this document, MassCEC recognizes that studies conducted under other methodologies may be equally valid. Rand Acoustics - Shelburne Falls, March 3, 2012
ISO and EPA Case Studies Annoyance Health Effects Rand Acoustics - Shelburne Falls, March 3, 2012
International Standards Organization, ISO/TC 43 New York: United Nations, November 1969. Rand Acoustics - Shelburne Falls, March 3, 2012
EPA Levels Document 1974. Similar method in ANSI S1.9 Part 4. Rand Acoustics - Shelburne Falls, March 3, 2012
0 +10 +5 NORMALIZATION: correction from urban residential to rural, intrusive: 20 dB +5 Rand Acoustics - Shelburne Falls, March 3, 2012
Response to noise from modern windfarms in The Netherlands, E. Pedersen,J. Acoust. Soc. Am. 126(2), August 2009. Rand Acoustics - Shelburne Falls, March 3, 2012
Unweighted 3 dB per doubling of distance dBA 6 dB per doubling of distance Rand Acoustics - Shelburne Falls, March 3, 2012
( PRIMARILY TRAFFIC ) < 30 "NOEL" Health Effects (WHO 2009) 30 - 40 "LOAEL" 40 - 55 > 55 Rand Acoustics - Shelburne Falls, March 3, 2012
Wind Shear – Stronger In New England Than On Test Stands. - Mass CEC wind noise regression method not supported. - Noise Reduction Options (NROs) don’t work. Rand Acoustics - Shelburne Falls, March 3, 2012
Developers often say that the wind turbine noise will be inaudible over the wind noise. IS “MASKING” REAL? Not until the wind turbine noise is very quiet. “From the experimental results it has been observed that the masking threshold occur when the wind turbine noise level is around 10 dB lower than the ambient sound levels.” Bolin 2009. Rand Acoustics - Shelburne Falls, March 3, 2012
Unweighted 3 dB per doubling of distance dBA 6 dB per doubling of distance Rand Acoustics - Shelburne Falls, March 3, 2012
Unweighted 3 dB per doubling of distance dBA 6 dB per doubling of distance A, C, and G-weighting filter response Rand Acoustics - Shelburne Falls, March 3, 2012
"The subjective annoyance increases markedly when the noise level is increased beyond 20 dB [indoors]. Recent research has supported the assessments behind the recommended noise limits for low frequency noise, and there is no doubt that loud low frequency noise is very annoying.“ Danish Ministry, January 2012. Rand Acoustics - Shelburne Falls, March 3, 2012
IN THE NEWS… In the mid-2000s Australian Upper house MP Simon Ramsay was a vocal champion of wind energy and obtained permits for turbines on a parcel of his own land, which he has since sold. His recent activism has included campaigning against turbines for which he previously held permits. .. the MP said the wind farm would damage his amenity at his family farm ''East Mooleric'', which had been in his family for generations, including from noise and interruption of his ''iconic views'' to the Otway Ranges. He sought a string of concessions, including that the company pay him $66,000 to grow trees as a noise and visual screen, and scrap all turbines within two kilometresof his home. (1.24 miles) http://www.theage.com.au/environment/energy-smart/mp-pressured-wind-farm-developer-20120221-1tlwc.html Rand Acoustics - Shelburne Falls, March 3, 2012
WHAT CRITERIA PREVENT ADVERSE IMPACT? - “Hold paramount the safety, health and well-being of the public.” (Ethics requirement; engineers, INCE.) - The only reliable noise control engineering method for wind turbines is distance. (NROs fail in high wind shear.) - Design to avoid widespread complaints. (Sound levels higher than 33 dBA are associated with widespread complaints in quiet rural areas due to noise increases.) - Design to avoid Low Frequency sound levels above 20 dBA indoors. (Apply Danish wind turbine LF noise limit). Rand Acoustics - Shelburne Falls, March 3, 2012
Thank you for listening. Robert W. Rand, INCE Rand Acoustics Brunswick, Maine Rand Acoustics - Shelburne Falls, March 3, 2012