Wind Turbine Noise Regulation · Wind Turbine Noise Regulation Perspectives in New England July 2010. Kenneth Kaliski, P.E., INCE Bd. Cert. New England Wind Energy Education Project

Wind Turbine Noise RegulationPerspectives in New England

July 2010

Kenneth Kaliski, P.E., INCE Bd. Cert.New England Wind Energy Education ProjectWebinar #2

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Typical noise impact study process

Identify preliminary turbine locations and sound power of turbine

Monitor background sound levels in representative areas (protocol-depending)

Conduct sound propagation modeling

Compare results to standards or guidelines

Refine turbine locations and remodel

Prepare report

Present testimony

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Determine sound power level of the turbine

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1/3 Octave Band Center Frequency

A-we

ight

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ound

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er L

evel

(dBA

)

Weighted sound pow er

Unw eighted sound pow er

Sound power of various turbines

Sound power by frequency

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Turbine Output (kW)

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Background sound monitoring

Identify sensitive receivers –homes, places of worship, schools, wilderness areas, campgrounds, etc.

Set up sound level monitoringShorter time frame if background levels are not critical to the standardLonger time frame for relative standardsSeasonal, if important

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Propagation modeling

ISO 9613

Sound power

Spreading Loss

Atmospheric attenuation

Barriers

Ground attenuation

Has significant impact on model results

Meteorology

Wind direction and speed effects

Sound generally propagates worse (i.e. lower levels at receivers)

UpwindUnder an unstable atmosphere, like sunny daysWith lower wind speeds and flatter vertical wind speed gradients

What is being modeled

•Modeling is typically done to estimate the maximum level, but we can also estimate sound levels under other conditions

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peci

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Sound Level (dBA)

What has been regulated

Total level

Usually expressed in units of A-weighted decibelsLevel by frequency

Full or 1/3 octave bandsTonality

Pure tone penalties and limitationsImpulsiveness

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Components of good regulations

Detail noise limits and parameters

Include application requirements

Detail components of pre-construction noise studies, including

—Details of background sound monitoring—Acceptable models and parameters—Spatial limits of monitoring and modeling—Modeled receivers

Address post-constructions issues

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Components of good regulations

Sound level limits

AbsoluteRelativeHybrid

Low frequency sound

Limit noise-induced vibration (ANSI S12.2)

Tonality (ANSI S12.9 Part 4)

Time-averaging

1-second, 10-minute, 1-hour, nighttime, daytimeTime above

Percent of any hour, day, or month

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Additional components of regulations

Exemptions and exceptions

Construction noiseMaintenanceEmergenciesWaivers

Complaint response procedure

Post-construction monitoring

Participation guidelines

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Examples of regulatory approaches

New Zealand

Specific to wind turbine soundMonitoring and modeling protocolsHybrid standard (greater of an absolute and relative level) with no maximumUses regression to determine wind speed/SPL correlationPenalties for tonality and impulsivenessDetails compliance protocol

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Examples of regulatory approaches

Oregon 340-035-0035 statewide noise rules

Existing regulation modified to address wind turbinesExisting regulations consisted of hybrid standard–greater of a relative and absolute level, with a maximumExisting regulations included tonal penalties and provided optional standard for octave bands

Wind turbine portion of standard established rules on participation and identified options for evaluating existing levels.

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New England States’ Wind Turbine Noise Regs

Maine

Statewide “Site Law” not specific to wind turbines—Absolute limits with lower “quiet area” limits—Measurement procedures—Penalties for

TonalityShort duration repetitive sounds

—Includes submission requirements—Exemptions—Variances—Waivers

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New England States’ Wind Turbine Noise Regs

Connecticut

Statewide noise regulations not specific to wind turbines—Absolute standard (except in high noise areas)—Penalties for

Impulse noiseTonesInfrasound and ultrasound

—Measurement procedures—Exclusions and exemptions—Variances—Violations and Enforcement provisions

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New England States’ Wind Turbine Noise Regs

Massachusetts

Wind farm precedents—Varied approaches to setting standards

Massachusetts Dept. of Air Quality Control Policy—Relative standard at property line and home—No pure tones allowed—No consistent approach on whether an how it applies to wind turbines

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New England States’ Wind Turbine Noise Regs

New Hampshire

No statewide noise regulationsSite Evaluation Committee Precedent—Absolute limit—Post-construction monitoring required

Vermont

No statewide noise regulationsPublic Service Board Section 248 precedents—Absolute limit measured inside and outside home—No pure tones allowed—Post-construction monitoring required

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Mitigation

•Re-siting project turbines• Increase setbacks• Reduce turbulence• Identify quieter turbines or components

•Automatic controls to slow tip speeds/reduce noise under specific conditions

•Improve noise insulation on target homes

•Increase the number of project participants

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Kenneth Kaliski, P.E., INCE Bd. Cert.

Resource Systems Group, Inc.

55 Railroad Row

White River Junction, VT 05001

kkaliski@rsginc.com

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Different modeling parameters yield different results

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Soun

d Pressure Level (d

BA)

Time of Day

Monitored Level Model Parameters 1 Model Parmeters 2 Model Parameters 3