To reach the goal of net zero, the world may need as many as 200,000 offshore wind turbines generating 2,000 gigawatts (GW) of energy.
To put this into context, by the end of 2022, 63 GW of offshore wind capacity had been installed globally. Within the next 28 years, the offshore wind energy sector needs to grow so that it is capable of producing 32 times its current energy capacity.
We need to figure out where to place all these extra offshore wind farms in order to maximize their energy output and their social benefits, while ensuring they have the minimum impact possible on the environment.
In order to define how much of the ocean we need to use to meet the 2050 net zero targets, we need to calculate the dimensions of the turbines, how wind power technology is likely to evolve between now and 2050 and the exact configuration of the turbines within a wind farm.
Combined, these factors control the future “power density” of offshore wind farms – how much offshore wind capacity can be installed per unit area of space in the ocean. The figure required for this is 4 megawatts (MW) per sq km. This means the area of ocean needed for offshore wind is roughly 500,000 sq km, which is around the size of France.
Once the total space is determined, the next task is to gather data on factors that constrain infrastructure development in the ocean. There are many constraints, from ensuring there is adequate wind speed for turbines to turn, to avoiding shipping lanes and marine protected areas, to whether seabed conditions are difficult to build on.
The study used 34 different layers of constraints, from which the available space for future sites is defined by excluding the no-go and crowded zones. The study identified the available ocean space for future offshore wind turbines as covering an area about 240,000 sq km, which is roughly equivalent to the area of the UK’s landmass.