One of Empire’s floating foundation design leads, Benoît Brière, gives us his thoughts on the future of floating wind foundations and why we need to act now if floating is going to contribute to a low-carbon energy future.

Benoît, how would you describe the current state of floating offshore wind?

It’s booming! It’s a very exciting time to work in floating wind. At the start of the year I read in a comment on social media that “2022 marks the end of the beginning for floating wind”, and I definitely think that’s the case. We’re onto the next phase now.

In January they announced the results from the ScotWind 1 auction in Scotland: 25 gigawatts of offshore wind were awarded and 15 of them were floating wind foundations, so that’s the majority. It’s a complete change of scale for the industry, and the first time we’re talking about these types of numbers and scale of projects.

Beyond Scotland, we’re seeing some real signs of regulatory frameworks being put in place in markets like Brazil and Australia. We’re also seeing projects taking off at various stages in southern Europe: we’re expecting a decision by the end of March from France to invest in two 250-megawatt projects in the Mediterranean Sea; late last year Italy received a crazy 64 expressions of interest for the development of floating in the country; and Spain is publishing a road map including one to three gigawatts of floating wind by 2030. In the Spanish case, the details of everything still need to be clarified, but it’s a clear sign we’re heading in the right direction.

Another sign that makes me very enthusiastic about floating wind is the fact that market leaders in bottom-fixed offshore wind – we’re talking about companies who have led the way in the offshore wind sector for 20 years or more – they are now entering floating wind. An example is the Danish company Ørsted that that has been one of the winners in ScotWind 1. The fact that companies that have been successful in bottom-fixed are thinking that they can be successful in floating, builds confidence in it and will ensure that lessons learnt from bottom-fixed are transferred to floating wind foundations. This I think will play a key part in floating wind’s success.”

What have floating wind foundations got going for them over bottom-fixed?

I think part of the answer is the same reason that led wind technology to move from onshore wind to bottom-fixed offshore wind: simply, there is just more wind resource farther from the coast which means a higher capacity factor – the percentage of time that the windfarm is producing at maximum capacity. So for floating wind further from the coast, you have the possibility of higher production for the same capacity installed.
“If you want to throw out some numbers: we go from capacity factors of 35 to 45% for good bottom-fixed sites to 50 to 60% on some floating sites, as we’ve seen with HyWind Scotland. That makes up for a large part of the added cost for going further offshore.

The second part of the answer is that there’s greater public awareness and acceptance of floating wind. So for example in France in 2021 there was a large and very comprehensive consultation around the possible development of the two 250-megawatt windfarms in the Mediterranean that I mentioned earlier. People were quite supportive of the floating wind because it has less visual impact on the coastlines. Being floating and further out, the windfarms would be far enough away from the coast so that you won’t be able to see them.
“In addition, if you go further from the shore, you have less competition for the sea space, for example with fishermen, and potentially with defence vessels and shipping lines. So that removes some of the pressure and means a project can be developed a little bit more smoothly too.

But my first two points are valid only for countries that have sites suitable for bottom-fixed. Not every country in the world can have a part of the North Sea, which is just a paradise for bottom-fixed foundations with the right water depths and seabed conditions in most places. With floating, you don’t need those. This opens new markets – now countries like USA, Japan or southern European countries on the Mediterranean can take advantage of offshore wind with floating foundations.

Finally, floating also has technical advantages, for example being able to decouple the mooring deployment and the floater hook-up, making installation simpler and reducing the need for large installation vessels.”

Ian Tran Empire Engineering

Benoît Brière, Lead Floating Engineer

What are the current obstacles to large-scale commercial floating wind?

We have to start with the cost, even though this comparison is irrelevant in some markets where bottom-fixed isn’t an option. Right now, in 2022, floating wind is producing electricity that’s more expensive than bottom-fixed. However, I think the ongoing energy crisis in Europe has shown the value of being able to produce power in winter, which is possible in most floating wind regions, at least in Europe, and this increases our cost competitiveness. So that balances things out a bit in terms of cost.

But the real challenge to address this cost issue is industrialisation. We’re at the end of the beginning as I said earlier: we’re at the end of pilot prototypes and pilot farms and now we need very large-scale deployment. So the next challenges is how to industrialise the industry. This step is absolutely massive. Take ScotWind, where we’re talking about installing 750 to 1,000 floaters –depending on turbine size – in a very short timeframe. All this is achievable, but the time to act is now.

I’d like to illustrate this point with a reasonable scenario for one of the ScotWind 1 projects. So when it’s commissioned in 2030, let’s say, this project will feature a 20-megawatt wind turbine that it’s not yet been prototyped. This wind turbine will be supported by a floater that’s assembled in a port that does not yet exist, or at least that’s not ready to host such construction projects, and this project will produce electrons transported into interconnectors that are still in planning. We could add that the maritime officer who will be captaining the tugboat for the floaters doesn’t even know they’ll be working in offshore wind yet. This scenario gives you a scale of the challenge. But I think it’s a very positive sign that everybody knows that these challenges need to be addressed and are gearing up to address them. So the time frame is reasonable, but the action can’t be delayed.

If you want a project to go online in 2030, you should be developing it right now or you should be about to enter a serious phase of development.

What role do you see floating wind playing in the future of low-carbon energy production?

I believe in 10 years’ time floating wind will be playing a key part of decarbonising electricity production. A 2022 report by the French grid operator RTE confirmed the feasibility of an electricity mix based on 100% renewables by 2050.

In the report, they address the need for storage and the need for flexibility in demand, and so on. The missing piece is a huge amount of green electricity production. Floating wind won’t be the only answer to this, but it will be part of the answer. But considering that we’re talking about gigawatts, I think it will be a key part of this mix that will decarbonise the electricity sector.

And then hopefully it will be part of decarbonising the energy sector in general. In the EU, for example, electricity represents just 25% of total energy consumption. So by 2050, if we’ll be using electricity to meet the needs of transport, heating and industry, we will need more renewable electricity. I think floating wind is very well positioned to meet this additional need, to decarbonise industry through the use of green hydrogen, for example.

If you look at the quantity and the capacity awarded in the ScotWind 1 auction, it’s clear they are already considering this, because current electricity demand in Scotland does not justify the numbers. People are already looking further into the future and planning for this.

What needs to happy in the offshore floating wind sector in the next few years for it to succeed? 

To get where it needs to go, floating wind needs steel production, we need port infrastructure. We need well-designed and successful auctions and optimised permitting processes. But before everything, I think floating wind projects are going to need talented people. The need for engineers and experts in the design phase where Empire is very active, will be enormous. I think the ability of the industry to recruit the best talent, to train them, to welcome experienced professionals from other industries and to grow organically – this will be tested to the limit. So I think it’s a very exciting journey to be part of.

Our R&D efforts also need to be focussed on industrialisation. If I look back at pilot projects, project optimisation was often based on lowering the mass of the floater. So you have the design department doing an excellent job on this aspect. Then the procurement department tries to find what’s needed to build the design, and the installation department goes to the port and tries to find the infrastructure it needs. And then there’s an iterative process because the port isn’t ready, or you have to adapt the design to use more competitive or available options.

Personally I don’t think this it will work for industrial scale projects. Very early on in the process, when you’re submitting your bid, you need to be able to have a general overview of all the design decisions that will lead to mass production, efficient installation and operation. It’s something I’m hoping to develop – a dashboard for decision makers where any important design decision at the early stage can be recorded and quantified economically in terms of cost and risk. Then all major decisions on cost and risk can be taken with the right level of awareness. With this in place you could quickly quantify the procurement implications of a design decision to allow for an informed choice early on, which could help generate successful bids. It’s the design life cycle approach to offshore wind that we take here at Empire.

So for example, you may have the option of using a mooring technology solution that’s optimised from a mooring design perspective. It’s protected by patent and it will allow you to reduce your mooring costs by 4%. Great! But what if there’s only one provider of this technology and there are hundreds of competing projects. What does it mean in terms of uncertainty and risk for your project? Is the 4% still worth it? Or should you go to for the second-best option in terms of net cost prediction? The one that is less risky. This is a kind of big-picture decision making that is very difficult to put in place because you need to have a very general view. But that’s what’s needed to achieve industrialisation.

Any particular market to watch? 

Floating wind is developing into a truly worldwide industry. There are some really positive signs in the USA; Asia-Pacific is a huge market; and not forgetting that today China is the number one offshore wind market in the world. Japan and South Korea are also emerging markets, and there’s Brazil.

But Europe is still a big focus. Scotland has put Europe on everybody’s radar in terms of floating wind. I’m very confident that that they will not be alone on this journey and that other countries in Europe are going to be a part of this. And this paves the way for the development of a specific floating wind industry in the continent and potentially opens opportunities for relocating some steel production and other industries here. So it’s going to be a very interesting area to work in in the coming decade.

As floating matures, are some floating wind concepts likely to disappear from the picture?  

I think this question has been in the air for a while now, because we’re pretty much at the end of a decade where it’s been all about prototype deployments.

I think today, considering the difference in site conditions in seabed types, in port infrastructures, I can’t see there being any clear winner or loser in terms of floater design concepts. Even the pioneers somehow pivoted from fit-for-all solutions to adapting their technology to project particulars. And I’m thinking about Equinor bid for ScotWind 1 which was unfortunately unsuccessful. It was based on a semisubmersible, rather than their original spar concept. BW Ideol, which is a pioneer of the technology, is proposing a steel floater rather than a concrete for the EOLMED project in the Mediterranean. These are examples of people adapting to available support, to the project, to the market.

I think in general, the winners in the coming decade, will be the ones that manage to achieve mass production. If your concept can be adapted to being mass produced and deployed efficiently for gigawatt-scale projects, then you will find clients, because there are going to be lot of gigawatt- scale floating wind projects in the future.

Empire specialists can effectively and efficiently assist in the selection process of concept types for floating wind foundations by utilising both qualitative and quantitative approaches. To find out more, please get in touch with the team at Empire Engineering.


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