Offshore wind turbines convert wind energy to electricity similar to how onshore wind turbines operate, which are common across Atlantic Canada. What is the opportunity for offshore wind turbines in Atlantic Canada? 

 What is offshore wind energy? 

Like onshore, offshore wind turbine blades spin from the force of wind (turning it into mechanical energy), which is then converted into electrical energy. Parts of the wind turbine work together, including the blades, which connect to the nacelle (the part between the tower and blades), which houses a generator, drive train, gearbox and brake, among other components. The blades are shaped and pitched specifically to maximize the amount of wind they capture.  

Offshore wind turbines differ from onshore wind turbines mostly with size and how they are supported. These turbines are not limited to the same land size or height constraints as those onshore; they can be significantly higher than onshore turbines – even double. Generation capacity grows significantly as the towers become higher and the blade longer.   

Larger towers are required for deeper water, along with strong bases to support them. Floating offshore turbines are also becoming increasingly common in other countries.  

Once the wind energy has been converted into electricity, underwater cables send electricity to an offshore substation which helps stabilize the electricity, and then onto an onshore substation where it can be connected to the grid or used directly to produce clean hydrogen. 

 

Offshore wind turbine

Source: New York State Energy Research and Development Authority (NYSERDA)

What are the pros and cons of offshore wind turbines? 

The operating environment (in water) typically leads to higher costs to produce wind electricity offshore. However, as technology improves, this gap in cost is expected to shrink. 

Because the wind blows faster and more consistently in the offshore environment, it provides an opportunity to add more dependable wind to the grid compared to onshore. Importantly, as the availability of onshore wind locations get used up, offshore wind offers significant new spaces to build renewable energy generation. 

What role can offshore wind have in Atlantic Canada’s energy future? 

The Atlantic provinces must add additional clean energy generation in the transition to net-zero, therefore it is expected wind energy will play an increasing and significant role moving forward. Onshore wind generation will likely dominate new builds in the short-term. Once policies are in place to allow for offshore, and as the gap in prices continue to fall, offshore wind may become a significant source of future electricity generation. 

Potential sizes between onshore and offshore wind turbines

Source: Nature Energy, May 2021, Expert elicitation survey predicts 37% to 49% declines in wind energy costs by 2050

The regulatory framework for offshore wind development for Nova Scotia and Newfoundland and Labrador is underway. In addition, offshore wind energy may also play a role in clean hydrogen production. The Government of Nova Scotia set a target to offer leases to produce 5GW of offshore wind energy by 2030 to support the clean hydrogen industry.  

Other jurisdictions, like the United Kingdom, Denmark and Holland have already built significant offshore wind farms (e.g. 2,200 turbines in 2020 in the UK).  

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Full disclosure: The Atlantica Centre for Energy represents many of the largest energy producers and consumers in Atlantic Canada, including renewable energy. However, the Centre’s members also represent governments, research groups and academia. The Centre examines all types of energy to help decarbonize while growing economies across the region.