To date, the development of floating offshore wind has been largely limited to pilot- and demonstration-scale installations. But much has been learned and the successful commissioning last year of Hywind Scotland – the world’s first floating offshore wind farm – heralds the beginning of the ‘take-off’ stage for the technology. Now, the focus is on moving beyond the pilot and demonstration-scale projects and towards the commercialisation and up-scaling of floating offshore wind. And like those achieved in both the onshore and bottom-fixed offshore wind sectors, with technological development and up-scaling come cost reductions. Floating wind is expected to follow a similar downward trajectory over the next decade, making it cost-competitive with other renewable energy sources.
It is thought that floating offshore projects have the potential to drive costs downwards by 40-50% by 2030. Indeed, Statoil has a stated ambition “to reduce the costs of energy from the Hywind floating wind farm to €40-60/MWh by 2030”, making it cost-competitive with other renewable energy sources. “This is an ambitious, but realistic target,” according to Irene Rummelhoff, executive vice president of Statoil’s New Energy Solutions business area. It can be achieved through design optimisation, the use of larger and more efficient turbines, technology development and up-scaling towards larger wind farms.
Looking ahead, it is clear that the potential for floating offshore wind is enormous. Unencumbered by the constraints of needing relatively shallow waters in which to install monopiles or other fixed foundations, deeper sites, further offshore, may be utilised. This opens up vast swathes of ocean that could, potentially, host floating offshore wind farms. It is estimated that up to 80% of all the offshore wind resources are located in waters deeper than 60 metres, where traditional bottom fixed installations are not suitable. As a result, “floating offshore wind is expected to play a significant role in the growth of offshore wind going forward”, according to Rummelhoff.
The seas and oceans off parts of west Europe, Asia and the US west coast are considered to be the most likely areas for the development of floating offshore wind over the next ten years. The Pacific coast of South America and the coasts of southern Africa and Australia are also thought to offer longer term potential.
From the current global total of around 50MW, only modest near term growth in floating offshore wind capacity is expected. A 2017 forecast from Bloomberg New Energy Finance, for example, foresaw 237MW of floating offshore wind being in place by 2020. But over the longer term, significant growth is in prospect. A forecast from Hexicon foresaw 500 floating turbines being installed by 2030. Based on turbines of, say, 5MW capacity, that would equate to perhaps 2.5GW of capacity.
In the decade to 2028, Windpower Intelligence expects to see floating offshore wind capacity being developed in European waters, as well as at sites off the United States, Japan and Taiwan. The first half of this period will see little – if any – large scale development, but the 2023-28 period could see significant capacity additions and we forecast a total of 2.25GW of floating offshore wind being in place in ten years’ time. In chapter 3, we consider the specific countries and projects that will contribute to this total.