Renewables, Wind

Relaxed Noise Restrictions Could Boost Wind Projects

Issue 10 and Volume 108.

The unique nature of renewable energy is having some unexpected effects on siting procedures and applicable state regulations. In Oregon, for example, noise regulations adopted in 1974 have impeded greater development of wind energy resources. A recent relaxing of state regulations could re-invigorate development activities.

Among other difficulties, the old rules required wind projects to show that turbine noise would not rise above background wind noise by more than a narrow margin in any one hour. Michael Grainey, director of the Oregon Department of Energy, said that provision has deterred developers and forced others to build fewer turbines than envisioned.

Oregon’s five existing wind turbine projects have the capacity to generate more than 400 MW, and about a dozen projects under way or proposed would more than double that capacity, according to the Renewable Northwest Project, which promotes development of wind, solar and geothermal energy in the Northwest.

When the noise standards were adopted 30 years ago, wind energy development did not exist on Oregon’s rural lands. Since then, they have restricted permitting of commercial scale wind turbines. One standard, the so-called Table 8 test, refers to Table 8 of the rules which limits the maximum permissible statistical noise levels generated by a project – typically the most restrictive is an hourly median sound level of 50 dBA. A second standard, known as the ambient degradation test, limits the increase in the existing noise level to a maximum of 10 dBA.

The ambient degradation test has proved to be the greatest impediment in permitting wind energy facilities. The degradation test requires extensive monitoring to determine pre-project noise levels and, in rural areas, results in large setbacks from landowners who may be indifferent to the increase in noise and who could benefit directly from project royalties.

In at least one real-case instance, the ambient degradation rule was preventing a landowner from re-occupying a dwelling on her land, even though she did not find the noise bothersome. In another case a home was vacated because the landowner was concerned that occupation would adversely impact or complicate the landowner’s chances of being included in a large wind development.

Oregon Gov. Ted Kulongoski is among those who believe the noise regulations presented unnecessary barriers to wind energy development, noting that economically depressed rural communities in Eastern Oregon and on the coast stand to gain the most from wind energy. In 2002, for instance, Umatilla County wind projects paid $893,098 in taxes to school districts and for such county services as fire protection. Individual landowners generally receive annual lease payments between $2,000 to $4,000 a turbine.

With the support of the Governor’s Office of Sustainability, the Oregon Department of Energy established a joint rule making with the Oregon Department of Environmental Quality to explicitly address noise standards for wind turbines. The Renewable Northwest Project (RNP), a regional nonprofit organization, was the primary advocate for the rule change. RNP was provided technical support from CH2M HILL, Inc. and legal advice from Stoel Rives, LLC.

The revised Oregon noise rules provide needed flexibility to effectively develop wind farms, while providing those individuals who desire it the same level of protection as the exiting noise rule.

The new rules establish a baseline pre-project noise level of 26 dBA, provide any willing landowner the ability to waive the 10 dBA ambient degradation standard while maintaining the Table 8 limits (50 dBA), and ensure that the maximum sound power level is used to evaluate project noise during permitting and compliance phases.

According to Mark Bastasch, an acoustical engineer with CH2M HILL, the effective setbacks between a wind turbine and a residence will likely exceed 1,000 feet for a consenting landowner and almost 3,000 feet for a non-consenting landowner, thus greatly simplifying the noise analysis required to permit a wind project in Oregon, and potentially speeding development of wind energy projects in the state.