Wind for oil – powering offshore facilities with floating wind turbines

By Michael Rogers

Part of Aker Solutions’ wind strategy is to provide power for brownfield activities
Part of Aker Solutions’ wind strategy is to provide power for brownfield activities (illustration: Repsol)

In early 2018, Aker Solutions invested in floating wind power technology company Principle Power Inc., forming an alliance that has enabled the company to transfer its offshore oil and gas field engineering expertise to the renewable energy market. The partnership has also boosted Principle Power’s WindFloat – an innovative floating foundation for offshore wind turbines.

Aker Solutions’ goal for the alliance is to offer coverage for the entire lifecycle of an offshore wind farm, including planning, installation, commissioning, operations and maintenance services.

Floating wind power has left the pilot stage and is now becoming commercial. This is visible in the results over the last year. Currently, three 8.5-MW units are nearing completion to be installed at WindFloat Atlantic in Portugal. Orders in the bag for the WindFloat include five units for installation in 2020 at the Kincardine wind farm offshore from Aberdeen, Scotland. Three more floats are slated for the France Golfe du Lion wind farm, offshore France, for installation in 2021.

Additionally, plans in the partnership include installation of 10 to 15 of the 10-MW floats in 2024 at Humboldt Bay, Northern California in the US.

Now, the alliance is targeting the offshore oil and gas market.

“Wind for oil”
On the Norwegian Continental Shelf, electrification from shore has become a reality for new developments. However, the expense of running cables from shore to brownfield platforms is prohibitive, opening an opportunity for alternative power solutions.

Drawing on experience with developing and managing offshore projects, which includes designing, delivering and servicing semi-submersible drilling and production platforms, Aker Solutions has been working towards applying its newly acquired wind farm knowledge to supply offshore power to brownfield activities.

“What we can do is to provide a very stable platform for wind turbines,” says Geir Olav Berg, Head of Engineering – Floating Wind at Aker Solutions. “We have a long history of delivering floaters – spars, semis and TLP’s so we know how these structures actually behave in the water.” Also, the WindFloat technology lends itself to quayside installation and maintenance, reducing the need for specialised offshore vessels.

Additional technology transfer includes applying Aker Solutions dynamic power umbilicals and cable expertise to wind farm cable arrays as well as export cables.

Lessons learned from subsea power, via partnership with ABB, are also a plus. Berg points out that power management is an important factor in the wind for oil concept. “Basically,” he asks, “how do you optimise the power usage on an oil and gas facility?”

“It means that you look at the process of power utilisation. For example, whether water injection is continuous or intermittent. Drilling facilities consume power – as do ESPs and gas lift. We need to see how we can balance all the power needs. Because if you can, the potential is to reduce some of the complexity of power generation,” Berg continues.

When asked about how to deal with the chance of intermittent power due to windless periods, Berg points to the possibility of using maritime energy storage systems.

Proven WindFloat technology
Proven WindFloat technology (illustration: Principle Power)

Carbon footprint
Berg says, “There are lots of considerations that need to be made when you are looking at wind for oil, but overall it can optimise production and reduce COemissions.” Plus, in addition to environmental considerations, lower COemissions mean lower carbon taxes.

Beyond environmental cost savings, eliminating generator fuel saves transport costs and enhances safety. “If you can get rid of the diesel power system on existing brownfield installations, huge savings are possible. There’s a high maintenance cost for power generation by diesel – and there’s also significant costs of logistics for moving fuel from onshore to offshore,” he explains.

Berg continues, “It’s carbon tax savings, it’s the opex of the turbine itself, it’s the capex of the turbine and is also the COfrom the gas turbines – there’s quite many factors involved. We use our extensive engineering experience and collaborative approach to optimise the overall business case together with our clients.”

The future
Although the Norwegian Continental Shelf sees electrification from shore as the go-to option for new fields, Berg says that Aker Solutions has already seen interest in the wind for oil offering for brownfield activities. “We are working with clients – on the UK sector, the Norwegian sector and in Brazil,” he says.

Berg also sees greater possibilities for the wind for oil concept: “The bigger the windfarm, the lower the capex per megawatt. So theoretically, supplying electricity to a field could also ‘share the costs’ with a more extensive wind farm that could supply electricity to shore.”