Since offshore wind farms generate renewable energy, you might assume they do not have any negative environmental impacts.
Overall, shifting towards renewable energy is better for the environment, and offshore wind farms may even be good for marine life by helping to restore coral populations.
There is still an environmental impact as building offshore wind farms requires energy and resources, which can cause pollution as well as disrupt wildlife.
Here’s everything you need to know about offshore wind farms and the environment.
1. What Are the Benefits of Offshore Wind Farms?
One of the main benefits of offshore wind farms is a reduced reliance on fossil fuels.
In 2020, approximately 80% of energy worldwide was made from fossil fuels, with renewables only making up 10 percent.
This is unsustainable, as fossil fuels are not only non-renewable but also huge polluters.
In the US alone, more than 70% of total greenhouse gas emissions are from fossil fuel combustion.
The carbon footprint of wind turbines is estimated to be more than 90% less than coal-fired power plants and natural gas and 75% less than solar power.
Although wind forcing the turbines to turn does not generate emissions, the carbon footprint is to do with setting up the wind turbines in the first place.
Wind turbines may also be a safer option for marine life, as they cannot cause oil spills.
With rising temperatures and ocean acidification, coral reef populations are declining, leaving many kinds of marine life without food and habitat.
Although wind turbines are not a solution to this, they can act as an artificial reef in some capacity and attract more diverse fish to the area.
Due to the size and shape of wind turbines, they can play a role in coral restoration.
This is because they are close to the water’s surface, so coral can receive enough sunlight without leaving them exposed to temperatures that are too high, resulting in coral bleaching.
Not only are corals a source of food and shelter for marine life, but they can even be a source of medicine.
While coral may not directly sequester CO2, they can still play a role in this due to their connection to mangrove forests and seagrass beds which act as carbon sinks.
Bottom trawling cannot occur near offshore wind farms, so they can serve as an area for fish populations to thrive.
With that said, offshore wind farms can attract recreational fishers, so they do not completely spare fish from this.
2. What Are the Downsides of Offshore Wind Farms?
Much of the downsides to offshore wind farms are to do with their construction.
As mentioned earlier, the carbon footprint of offshore wind farms is due to sourcing the materials to build them and setting them up in the first place.
None of these materials are renewable.
Mining for metals is a huge source of pollution and can also physically harm the environment due to deforestation and soil erosion.
The steel sector was behind more than 3.3 billion tonnes (three trillion three hundred billion kilograms) of greenhouse gas emissions in 2021.
Creating fiberglass is also a big source of pollution.
It then requires energy to convert all of these materials into a usable form to build wind turbines.
Wind turbines have quite a long life span and can last between 20 to 25 years.
However, they are difficult to recycle, so this can generate huge amounts of waste.
Offshore wind turbines also need maintenance to ensure they are working efficiently.
Deploying staff in ships to do so will also have an environmental impact, as many kinds of ships rely on fossil fuels and release emissions.
Not to mention, traveling to the offshore wind farm to replace defunct wind turbines would also cause pollution.
3. Do Offshore Wind Farms Affect Marine Life?
There are several ways offshore wind farms affect marine life.
As mentioned earlier, they can act as artificial reefs and attract fish to the area.
Constructing offshore wind farms can disrupt marine life due to noise pollution.
Noise pollution can cause hearing loss, leaving fish more susceptible to predators and struggling to find food or other fish to mate with, potentially impacting populations.
Even if fish do not experience hearing loss, the noise can leave them struggling to catch prey as they cannot hear the sounds they make or vice versa, leaving fish exposed because they cannot hear approaching predators.
This can disrupt the natural predator-prey balance in the ecosystem.
It can also force the fish to relocate elsewhere, which will also disrupt the ecosystem.
The stress from the noise can also have negative health consequences, such as tissue damage and even death.
While offshore wind turbines can offer migrating birds a place to rest, they can be a double-edged sword, as seagulls can also be injured or killed by crashing into the wind turbines.