Environmental Effects of Wind Generation

Onshore Wind

Environmental effects of wind power generation are primarily limited to land use, habitat, and wildlife interference, as there are no greenhouse gas emissions related to the generation of power itself. While wind farms use a significant amount of land in total area (the acreage is site specific, depending on the configuration and geography of a project), much of that land is either undisturbed by the development or multi-purposed. Wildlife interference occurs in two ways: direct mortality due to collisions with the wind turbines and indirect impacts to wildlife due to the loss of habitat in which the wind project resides.

As wind turbines reach the end of their useful life, decommissioning of plant components and the magnitude of waste created becomes an issue. Most of the wind turbine components can be recycled, salvaged, repurposed, or sold on a secondary market. However, there is not currently an adequate solution for decommissioned wind turbine blades – composed of composite fiberglass and resin. Oftentimes, blades are simply disposed of in landfills because it is the most economic option. The size of the blades can create a substantial issue for local landfills with limited capacity to grapple with, and transportation of blades to designated waste areas can get very expensive.

There are several initiatives underway to tackle and resolve the waste issue created by wind turbine blades. Manufacturers are actively seeking to develop recycling programs that would take the fiberglass from the blades and repurpose the material in the production of cement. The American Wind Energy Association (AWEA) has suggested that the decommissioned blades could be repurposed in local communities through the creation of pedestrian bridges, playground equipment, and highway sound barriers – to name a few examples. In addition, manufacturers, scientists and researchers are exploring how to build a wind turbine blade made from components that can be recycled at the end of its useful life. Further, efforts are being explored to salvage old wind turbine parts – including blades - to create fully recycled wind turbines for future deployments.

Much of the land and wildlife effects are mitigated during the siting and licensing of wind projects, although the effects of a significant deployment of onshore wind in a short amount of time are not yet fully understood. See the presentation on this topic at the June 2021 Council Meeting.

Offshore Wind

The environmental effects of offshore wind include impacts during construction and decommissioning, noise during construction and operation, and disruptions to local ecosystems and behavior of wildlife. The development of an offshore wind project includes significant machinery, complex logistics, and major installation of equipment beyond the wind turbine itself (e.g. underwater transmission cables to transport the electricity to onshore substations). All of this leads to the disturbance of the existing habitat.

With the introduction of equipment at, above, and below the surface of the water, many marine species are affected. Under the water, species such as mussels and algae are attracted to – and can colonize – the structure and cables. This can cause the creation of artificial reefs and an increase in marine life and species diversity. One drawback is that an artificial reef can also attract predators and introduce new, invasive species to the ecosystem, leading to predation and threatening the existing species through competition of habitat and food sources. Underwater structures may also be spread out over a wide area, which can lead to disruption and entanglement of marine populations that typically forage and migrate through the offshore wind project area. At the surface and above the water, structures pose similar risks of collision and entanglement to seabirds (which may be more attracted to the area due to the increased marine life) although the risk is less as the structures are large enough to be visible. If equipment is close to the shoreline, breeding grounds may also be disrupted or affected. Noise – during construction and operation – may disturb the wildlife in the area, although the severity likely depends on the species.