Understanding the Evidence: Wind Turbine Noise

Summary

Demand for renewable energy, including wind power, is expected to grow in Canada and around the world. The wind sector has expanded rapidly since the 1990s, and Canada is now the fifth-largest global market for the installation of wind turbines. However, this new source of environmental sound has raised public concerns about potential health effects on nearby residents.

Determining whether wind turbine noise causes adverse health effects is an important issue. In response to public concern, Health Canada asked the Council of Canadian Academies to conduct an in-depth expert panel assessment. The panel’s report presents findings on the acoustic characteristics of wind turbine noise, evidence on causal relationships between exposure to wind turbine noise and adverse health effects, knowledge gaps and further research, and promising practices to reduce adverse community response. The resulting report is evidence-based and does not espouse recommendations. Its purpose, rather, is to assess the scientific evidence on the question of wind turbine noise and human health in order to provide a foundation of knowledge to support governments, policy makers, communities, and the industry.

Key Findings

The panel used a comprehensive approach to identify and review relevant research. They identified 32 symptoms and health outcomes that have been attributed to exposure to wind turbine noise by members of the general public (e.g., annoyance, sleep disturbance, stress, irregular heartbeat, muscle pain etc.). The Panel then reviewed the empirical research for those symptoms and selected 38 key papers that constituted the core evidence base for their assessment.

• Sound from wind turbines is complex and variable.
• Standard methods of measuring sound may not capture the low-frequency sound and amplitude modulation characteristic of wind turbine noise.
• The evidence is sufficient to establish a causal relationship between exposure to wind turbine noise and annoyance.
• There is limited evidence to establish a causal relationship between exposure to wind turbine noise and sleep disturbance.
• The evidence suggests a lack of causality between exposure to wind turbine noise and hearing loss.
• The Panel found inadequate evidence of a direct causal relationship between exposure to wind turbine noise and stress, although stress has been linked to other sources of community noise.
• For all other health effects considered (fatigue, tinnitus, vertigo, nausea, dizziness, cardiovascular diseases, diabetes, etc.), the evidence was inadequate to come to any conclusion about the presence or absence of a causal relationship with exposure to wind turbine noise.
• Knowledge gaps prevent a full assessment of public health effects of wind turbine noise.
• Research on long-term exposure to wind turbine noise would provide a better understanding of the causal associations between wind turbine noise exposure and certain adverse health effects.
• Technological development is unlikely to resolve, in the short term, the current issues related to perceived adverse health effects of wind turbine noise.
• Impact assessments and community engagement provide communities with greater knowledge and control over wind energy projects and therefore help limit annoyance.