Noise Control & Reduction for Power Generation Industries

The Power of Wind

Posted by Payam Ashtiani /

Wind power noise regulations explained

Recent commitments made by Canada’s Prime Minister Justin Trudeau at COP21 outline the current desire across the country to push towards renewable sources of energy production and cutting our country’s carbon emissions. A majority of that new renewable power is expected to come from wind power generation. This post explores the different ways parts of Canada regulate noise from wind power facilities. Permitting of Wind Power in Canada is regulated at a provincial level. As such, different jurisdictions have slightly different approaches to regulating noise from wind power facilities.

Ontario

Ontario has had noise regulations on industry for the past 30 years. Since 2004, Ontario has had noise guidelines specific to wind power. The guidelines specify how noise from wind power facilities is to be modelled, what the sound level limits are, and how post construction measurements should be carried out. The guidelines, first introduced in 2004, were updated in 2008 to include additional details, and had evolved based on latest findings in the literature at the time. In 2011, detailed post construction measurement protocol was introduced in order to standardise the post construction measurement requirements both from an instrumentation perspective and from an analysis side. The noise modelling guidelines have now been updated yet again in 2016. With these new updates, the noise modelling guidelines for wind farms would include specific key requirements:

  • The use of a conservative ground factor of G=0.5 in the noise model according to ISO 9613-2
  • The addition of a manufacturer’s uncertainty to the noise source level in the model
  • Consideration for topographical elements such as valleys that would increase the predicted noise level in situations where a noise source and receiver pair are located across a valley

These proposed changes are expected to apply to a new batch of wind and solar energy sites awarded as part of the Ontario Large Renewable Procurement (LRP 2) process, and to any anticipated plans in relation to the recently announced and anticipated cap-and-trade program.

In addition to very detailed noise modelling requirements, Ontario also requires a fairly involved post construction noise monitoring endeavour that includes measurements of a batch of turbines post installation to verify noise emission, as well as verification of sound levels at most effected dwellings in the project area from the turbines and transformer substation of the project. See: Wind Turbines: So what’s all the noise about?

Saskatchewan

Environmental noise requirements in Saskatchewan are not as specific as those in Ontario mentioned above. There are currently no Saskatchewan specific noise regulations for energy projects. However, most projects that undergo approvals do require a noise study to be completed. Because of the comparatively lower population densities of Saskatchewan, wind turbine noise has not been regulated with as much detail as other provinces. Most studies usually follow good practice guides from guidelines from nearby provinces in the assessment of noise during the permitting process. Post construction noise monitoring has also been prescribed by the Saskatchewan Ministry of Environment – although no specific requirements on a methodology are spelled out at this point. A developer looking at a project in Saskatchewan is recommended to define the measurement methodology under which post construction monitoring would take place. This is especially important due to the relative difficulty in obtaining useful and representative data in relation to the noise impact from wind facilities.

Alberta

The Alberta government is expected to soon release plans for encouraging more renewable projects to develop as it aims to phase out coal power plants and reduce the greenhouse gas emissions of its energy sector.

Alberta has historically had provincial noise regulations for the Energy and Resources industries under the Alberta Energy Utilities Board (EUB). Noise regulations in Alberta date back 20 years. In more recent times, however, the regulatory jurisdictions have been split between the AER (Alberta Energy Regulator) and the AUC (Alberta Utilities Commission). The AUC regulates energy utilities including wind power plants. Noise is regulated under AUC Rule 012. The rule has been steadily updated, with its latest version issued in April 2013. The more recent updates have been primarily to address wind facilities, and the specific aspects of wind turbine noise that make them unique. AUC Rule 012 requires the addition of third party facilities (even non-renewable) under the jurisdiction of the commission, as well as the addition of an assumed ambient sound level (ASL) to the noise impact model predictions. The cumulative sound level limit then has to satisfy the prescribed limits depending on the density of the population (40dBA cumulative for nighttime rural environments). Post construction measurements are also a common requirement for projects that are approved. The AUC limits are the most restrictive in Canada, and require a considerable effort to identify all existing and a planned third party sources locations and acoustic emissions.

Canada continues to be a supportive environment for the development of renewable energy, with many regions having highly developed noise regulations specifically for wind facilities. Having such a well developed regulatory system is a win-win for all parties: Developers know that if you play by the rules, your project will likely be approved – even if the approval process is sometime long and painstaking; Regulators know that a consistent set of guidelines and rules are applied to all projects, and that the communities in their provinces are adequately protected from pollutants such as noise. A robust formal approval process also ensures that they get project developers who are committed to the process, and should understand the rules of the game.

If you would like further guidance through this process, please contact us at [email protected].

Payam Ashtiani

Principal

As a Principal at Aercoustics, Payam loves the breadth of knowledge in the company that constantly allows for innovation and re-writing of the technical rules used in the industry.

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