Q&A: Black & Veatch on key success tips for floating offshore wind

inspiratia caught up with Peter Clive, principal wind energy consultant at Black & Veatch, to discuss the current state of floating offshore wind and the future opportunities for the technology  

Floating offshore wind has the potential of more than 10TW of capacity – approximately four times the global renewables capacity at the moment – in emerging markets alone, excluding Europe and North America.

With price parity with fixed-bottom offshore wind expected by the end of the decade, all signs point to the tremendous opportunity the technology presents.

To this end, we chatted with Black & Veatch's Peter Clive to draw from the company's longstanding experience mastering the mysteries of wind technologies, to learn about what can make floating offshore wind cost-competitive, savings from the supply chain, key considerations for project sponsors and financiers, and the new technical challenges that arise.

Black & Veatch is a global engineering, procurement, consulting and construction company founded in Kansas, United States. The company has a 100-year legacy of innovations in sustainable infrastructure.

What are some of the key advantages of floating offshore wind compared to bottom-fixed offshore wind?

Bottom-fixed solutions are limited to water depths shallow enough for foundations to be installed economically, typically 50m or less. Floating wind is not as constrained by water depth and so can be used to access the abundant wind resource available in areas where the water depth puts it out of reach of fixed-foundation offshore wind turbines. This can include regions with stronger winds, which then results in higher production. Great examples include call areas off the west coast of North America, where depth drops off quite rapidly and resource is excellent, for example in the waters off Humboldt County in northern California.

What is the global potential of floating offshore wind power?

Recently the Energy Sector Management Assistance Program (ESMAP) – a collaboration between World Bank and 18 other partners – looked at 48 emerging markets and concluded there was a technical potential of 15.6TW of offshore wind power within 200km of the shore in depths up to 1km with wind speeds greater than 7m/s. If you require floating foundations for depths greater than 50m this equates to 10.1TW, or nearly two thirds of that technical potential. To place that in context, that's nearly four times the world's currently installed renewable energy capacity, equivalent to around half the world's total primary energy supply, and roughly equal to the amount of new renewable energy capacity we need to install by 2030 to meet our decarbonisation targets, according to IRENA, which requires a 6-fold increase in the rate at which we are currently installing capacity a target that is in line with the latest IEA roadmap for the global energy sector. And note that this ESMAP survey only covered 48 emerging markets, and did not include well established markets in, for example, Europe and North America. The IEA roadmap foresees an annual capacity addition of 80GW of offshore wind by 2030, when it anticipates floating wind will start to make a major contribution.

What kind of floating offshore wind projects has B&V worked on?

Black & Veatch have been involved in a variety of projects, from operational wind farms to projects in various stages of development. Crucially our involvement has drawn on a number of strengths we have, from wind resource assessment and energy yield estimation, to the measurement of wind conditions using floating lidar, to electrical connection and power transmission challenges, to energy storage options. 

Currently the LCOE of floating turbines is higher than fixed-bottom turbines. How long will it take for floating wind turbines to become cost-competitive?

The most recent levelized cost of energy (LCOE) studies suggest parity will be achieved by the end of the decade. Cost reduction plays a significant role in this, but perhaps the biggest contribution will be from enhanced capacity factors, in line with our ability to access more favourable wind resource when not constrained to sites where we can install fixed foundations. We currently see demonstration projects like HyWind Scotland consistently delivering capacity factors – 54% over the first two years of operation, 57% in the most recent 12 months – that outstrip what is achieved with fixed foundation offshore wind farms, for example, the UK offshore wind average of 40%. This level of production will drive down the cost of energy.

In addition, we shouldn't just consider comparisons between different offshore wind technologies, but where those technologies sit relative to the wholesale power price. Approximate UK bottom-fixed offshore wind strike prices have already dipped below this in auctions for contracts for differences (CfDs) for projects due to be in operation in 2023/24 – effectively making them subsidy free. It is estimated by ORE Catapult that floating wind power may follow suit by the end of the decade.

Where in the supply chain can costs be reduced?

Drivers of cost reduction could include increase in project experience; economies of scale (in relation both to wind turbines and wind farms); standardisation of operations and mass fabrication; innovations that allow the optimisation of, for example, moorings and substructures, and innovations that introduce new concepts, such as park level control, and new materials; the integration of storage (including, for example, batteries, compressed air, liquid air, flow batteries, and the synthesis of green hydrogen and ammonia); digitally integrated operations and infrastructure, including sector coupling; the transfer of skills and experience from other sectors such as oil and gas; reductions in the cost of capital; improvements in the consenting process; and, as has been mentioned above, increased capacity factors.

Another impact on cost of energy is the size of the turbines themselves. LCOE optimisation studies suggest that this will increase, but not necessarily indefinitely. Once factors such as the availability of suitable port facilities for fabrication and support, distance to demand centres, available resource, and so on, are taken into consideration, the optimal size may be somewhere between 15MW and 20MW, although 20MW+ wind turbines are still being contemplated. That's not too far off where we are now, with, for example, the GE Haliade-X 13MW, Siemens Gamesa's 14MW 222m rotor diameter direct drive machine, and Vestas' V236 15MW wind turbine on the cards. It is noticeable that reality consistently outstrips expectations in this regard, as progress happens earlier than predicted.

What do you think are some of the main technical risks or challenges involved in developing FOW technology?

Demonstration projects so far have performed very well, beyond expectations. As with everything, we need to consider operational conditions that are outwith the evidence base provided by demonstrations so far. This includes moorings and station keeping in greater depths, power transmission challenges over greater distances, providing support for operations and maintenance over greater distances, and Power-to-X (P2X) alternatives to the conventional export of electrical power, such as electrolysis of green hydrogen in situ at scale. Nevertheless, excellent progress is being made on all these fronts.

What should developers look for when going into a new jurisdiction?

Political will is important for setting priorities in the context of broader cycles of infrastructure development, to ensure ancillary considerations are accommodated, such as ports and grid. Those setting the agenda in the new jurisdiction should clearly signal strong and consistent support for offshore wind power developments. Indeed, even in circumstances that are not ideal, consistency at least supports confidence in the decisions made to address those circumstances. There may even be an initiative or strategy in which an offshore wind project would be a suitable element.

Permitting requirements should be clear and the developer should pro-actively engage with stakeholders and seek to anticipate consenting issues rather than wait to comply with the requirements of a permitting process as these arise, to avoid unforeseen delays as much as possible. Therefore, developers should look for all potential project impacts at an early stage of investigating the new jurisdiction.

What are the technical strengths a project needs to have?

As well as good wind resource, well understood metocean conditions, appropriate turbine and foundation technology, proximity to port facilities for operational support, and provision for exporting power production, the profile of the resource should be well characterised. There is no substitute for direct measurement of wind conditions on site. These can reduce the error bars of production estimates based on models, and capture crucial information about complex aspects of the wind conditions that elude models but nevertheless have real-world impacts on asset productivity and reliability.

How is floating LiDAR technology driving floating offshore wind farm development and supporting resource assessment?

The direct acquisition of data at a project site during the wind farm planning and design stage, prior to construction, is crucial for obtaining key information, not just about wind resource, to support revenue estimates necessary for raising finance, but also about wind conditions relevant for engineering design, to ensure the most appropriate turbine and foundation technologies are selected. The only way to obtain these data in the water depths in which floating wind turbines are being deployed is by using a floating lidar.

Lidar has changed the way we look at measurement. Initially we used lidar to replicate met mast functionality at lower costs, greater convenience, or where the acquisition of data would not otherwise be possible. However, lidar has capabilities with no met mast analogue. The greatest value is unlocked by using them to do things we might not necessarily even consider doing using met masts, to acquire insights that would not otherwise be available. This has made us look at measurement use cases differently. We no longer ask "what can I measure" but "what do I want to measure" and adopt outcome driven approaches to measurement campaign design, rather than constraint driven ones. This ultimately leads to better projects, once we modify our procedures to capitalise on the opportunities for improvement made available.

What expertise can O&G companies transfer to accelerate the floating offshore wind industry?

Clearly expertise in the fabrication, deployment and operation of floating maritime facilities of any sort gives O&G experience and expertise that is directly relevant, in addition to those areas where transferable expertise is already being exploited in the context of fixed foundation assets. There are additional areas that will be interesting to watch. For example, we should consider where floating wind can be integrated into broader infrastructural contexts in ways that are not based on simply replicating established forms of power generation and transmission, but exploit unique attributes of floating wind to provide optimised solutions. We already see this with Hywind Tampen, where floating wind is being used to reduce the cost of providing power to offshore O&G facilities.

It had been speculated that niche demand in areas like this would drive early adoption of floating wind at an intermediate scale (~100MW) between demonstration projects (~10MW) and utility scale power plants (~1,000MW), and consolidate the readiness of the technology for that broader utility scale deployment. However, it seems to me this is being leapfrogged to some extent, and we are moving towards utility scale deployment before the end of the decade without necessarily requiring a lengthy period of operation of intermediate scale facilities first. The extent to which this will be the case remains to be seen.

What technological innovations and developments do you expect to see in five years' time?

It will be interesting to monitor the opportunities that emerge for P2X. For example, the current shift in marine propulsion away from fuel oil and towards alternative fuels may mean it makes sense to situate floating wind farms and other marine renewables near to shipping lanes so that shipping can access fuels en route. It is also tempting to speculate that other developments in energy storage might have unforeseen synergies. For example, if compressed air energy storage was achieved by inflating reservoirs at depth, the heat exchange necessary for achieving isothermal storage efficiencies might support benthic aquaculture in one location and refrigeration at another.

Outstanding Technical Adviser is one of the categories at inspiratia's inaugural Energy & Sustainability Awards, for which we are very excited about. The ceremony is set to take place on 28 October [2021]. Find out more about the awards, the categories and the criteria for submissions here. Deadline for submissions is 16 July.