Over the last ten years the offshore wind industry has become commercially mature with well-developed supply chains, significant technology advances driven by competition, and resulting wind farm capital and operating expenditure decreasing at a remarkable rate.
The marine-civil construction sector that traditionally supports infrastructure development can be credited with a large part of this success, as they have adapted their equipment and applied their experience in harbour and port development, dredging, over-water bridge construction and underwater cable laying to the installation of bottom-fixed wind farms in the sub-45-metre water depth they are accustomed to working in.
Floating wind power is now emerging as the next offshore frontier, which is pushing the marine-civil sector into unfamiliar territory: deep water. The attendant challenges of this shift are amplified by the emergence of the new giant 12-15MW turbine models that floating platforms will be expected to support.
Technology transfer from the oil & gas industry, which decades ago ventured from bottom-fixed drill rigs on jackets to immense floating platforms, will be key to speeding the migration of offshore wind into deeper water plays. This acceleration can be accomplished by adapting oil & gas experience to deep-water offshore wind to manage and reduce risk.
Adapting offshore oil & gas experience to deep-water wind is easier said than done
The oil & gas sector has already designed and installed a vast fleet semisubmersibles, tension-leg platforms and spars – concepts which have all been adapted for floating wind – in water depths exceeding 2,000 metres.
But it is not just its impressive record in dreaming up and developing the technical elements that underpinned this success – the floating platform design, mooring system design and installation, anchor technology development, subsea operations, offshore platform access and so on – that points to the oil & gas industry’s ability to support wind power wading out into deeper waters: there are also the non-technical elements that oil & gas has become expert in, from contracting frameworks to cost-savvy engineering approaches, that also have the potential to be deep-water wind accelerators.
Adapting offshore oil & gas experience to deep-water wind is easier said than done, however. While we are already seeing oil & gas sector companies teaming up to participate in floating wind, and though there do exist a number of overlaps between the sectors, challenges remain.
Many of these stem primarily from the radical differences in project economics between the two sectors, but also from differences in the application of technologies and in basic project structures. A one-off mega platform supporting an oil production plant generating $15m/day in revenue and a wind farm with 100 small platforms each supporting one wind turbine and collectively generating $1m/day in revenue are hard to compare.
The direct application of oil & gas technologies currently drives the cost of floating wind above the acceptable levellised cost of energy thresholds, which bottom-fixed technology advances continue to push lower and lower. The conventional floating offshore oil & gas platform supports a production plant while controlling the dynamics and stresses in pipework (and risers) drilled deep into the seabed, whereas a wind turbine mounted on a floating foundation is an integrated aero-hydro energy-generating machine.
Floating wind turbine engineering analyses are fundamentally quite different and have not yet been fully addressed by the oil & gas sector. On the other hand, a floating wind turbine does not have the technical complexities, risks and associated costs related to human occupation on board as well as the presence of the dangerous hydrocarbons found on oil & gas platforms.
One of areas in offshore oil & gas that might be provide the greatest boost to the nascent floating wind industry – one closely related to the transfer of technology – is the transfer of engineering methods and approaches that develop technologies.
The oil & gas sector has, over many years, evolved a highly structured front-end engineering and design (FEED) process that emphasises and relies on engineering to reduce risk. The result is that the industry has development a means of the deploying unique mega-platforms without a preceding prototype, with risk managed by employing the traditional naval architecture design approach that combines empirical data from past experience and previous designs, extensive model testing, sub-system tests, and advanced engineering analysis to design a new, unique floating vessel or platform. This rigorous FEED strategy could be a game-changer for deep-water wind, by-passing the need for floating wind foundation prototyping and demonstration projects.
So how can a synergistic relationship between the oil & gas sector and the marine-civil construction sectors accelerate deep-water floating wind? It starts by each sector bringing relevant experience to the table, then brainstorming and innovating to implement a systemic change in the oil & gas mentality and culture as well as an expansion in the marine-civil approach. Technology transfer needs to go both ways. Then through teamwork and cooperation, synergies will develop and successful floating wind projects will be realised. The opportunity is here and it's time to get to work.
- William Hurley is past president of international offshore engineering outfit Glosten, which is developing the PelaStar TLP floating wind turbine platform concept. He will be presenting at the Business Network for Offshore Wind’s upcoming Floating Frontiers: Offshore Wind in the US conference, on 11 July in Houston. Recharge is a media partner of the event