The floating offshore wind market looks likely to be dominated by semi-submersible platforms despite the early lead taken by Equinor using spar-buoy technology.

Figures collated by the research firm IHS Markit indicate that semi-submersible platforms could be used for at least 163 megawatts out of almost 178 megawatts of floating wind projects currently financed, consented to or applied for worldwide, potentially giving it an early market share above 90 percent.

The level of interest in semi-submersible platforms far outstrips that for Equinor’s spar-buoy foundations, which helped the Norwegian developer become the first to market with its 30-megawatt Hywind Scotland project, completed in 2017.

The largest of the upcoming projects is the Kincardine Offshore Windfarm, a 50-megawatt plant off the Scottish coast that will use semi-submersible foundations provided by U.S. supplier Principle Power.

A 2-megawatt Vestas turbine started delivering power to the grid from the Kincardine project last October. The wind farm, majority-owned by Spain's Cobra Wind, is expected to be fully operational by 2020.

Including the Kincardine project, almost 104 megawatts of semi-submersible-based floating wind capacity could be online by the end of 2020, IHS Markit estimates.

Principle Power's early edge

Other sources also point to semi-submersible platforms taking the lion’s share of the floating offshore wind market.

Quest Floating Wind Energy, a specialist analysis firm, has cataloged the platforms that will be used for 419 floating turbines across 27 projects presently planned or under development.

Of these platforms, 281 will be semi-submersibles, 72 will be spar-buoys, 32 will be semi-spar concepts from Stiesdal Offshore Technologies and Saipem, 31 will be barge designs, and three will be tension leg platforms (TLPs).

Quest’s data shows that the dominance of semi-submersible platforms is for now overwhelmingly attributable to a single player: Principle Power. As well as having been selected for Kincardine, Principle Power’s WindFloat design is already in operation in Portugal and is soon to enter operation in Japan.

The concept has also been slated for two projects that the Danish developer Alpha Wind Energy has proposed off the coast of Hawaii. These projects, each for 408 megawatts and not included in the IHS Markit figures, would involve 102 WindFloat-based turbines.

However, said Erik Rijkers, director of market development and strategy at Quest Floating Wind Energy, “We know that Equinor is also a player there and they and others will eventually balance out with Principle Power.”

Moving beyond oil- and gas-based designs

Intense competition seems inevitable in the nascent floating offshore wind platform market. Today there are only three floating wind energy projects in operation, all of which are in Europe.

But Principle Power is set to extend its reach with new platforms going into the sea off Portugal and Scotland this year and next.

Next year, or perhaps 2021, will also see a slew of precommercial projects going live in France, with floating foundations from Principle Power, Ideol, Naval Energies and SBM Offshore, Rijkers said.

These early players have by and large copied platform designs similar to those used in oil and gas, he said. But from next year onward, a new generation of designs is set to enter the water as part of demonstration projects.

The platforms will include Stiesdal's TetraSpar in Norway, Aerodyn Engineering's SCDnezzy and Ideol's Damping Pool in Japan, Saitec’s SATH and Wunder Hexicon's multiturbine platform in Spain, and Saipem's Hexafloat in Ireland. 

Semi-submersibles’ early dominance of the floating offshore wind market is clear despite the fact that exact figures for each technology are open to interpretation because of uncertainty over how floating platform concepts should be defined.

At this stage of the market, there is practically no standardization of floating foundation designs. A 2015 review by the U.K.-based Carbon Trust, issued on behalf of the Scottish government, identified 31 designs from as many technology developers.

These were grouped into four broad categories: semi-submersible platforms, spar-buoys, TLPs and multiturbine or hybrid concepts. Some platform developers are reluctant to conform to this classification, however.

For example, Carbon Trust and IHS Markit both classify the damping pool design promoted by the French firm Ideol as a semi-submersible platform. But the developer claims it is “a unique barge design.”

Ideol’s chief sales and marketing officer, Bruno Geschier, told GTM the patented floater design was getting “tremendous interest from developers across the globe, particularly since its two full-scale demonstrators have confirmed the claims we have been making for years.”