A new wave of greener vessels

Decarbonising an offshore services fleet

Matthew Gordon hails North Star’s fleet decarbonisation strategy as a gamechanger for the business, and for offshore industry

As the maritime sector implements strategies to move away from its dependency on fossil fuels, North Star, the UK’s largest offshore installation infrastructure services company, is a frontrunner, with its decarbonisation programme well under way.

While its new offshore wind fleet, to be delivered from early 2023, has been designed with sustainability and future fuels in mind, North Star is also committed to the green transformation of its existing Emergency Response and Rescue Vessel (ERRV) tonnage, improving its environmental performance and operational efficiencies.

The carbon-neutral status of its onshore operations in Aberdeen, Newcastle and Lowestoft has been internally scrutinised, and the business is hiring a sustainability lead to keep driving forward its culture of climate resilience.

North Star, which employs circa 1,300 crew and personnel, has a proud heritage. It was established over 135 years ago to provide support to the North Sea fisheries industry. When the region’s oil and gas sector emerged in the 1970s, the firm adapted its tonnage and widened its maritime skills to support the boom in exploration and production work. Today it boasts the largest marine fleet wholly owned by the UK, and has unrivalled maritime expertise in the North Sea, delivering around the clock operations and exceptional ship management, including in-house repair facilities. Its ERRV fleet, the largest on the UK continental shelf, provides essential crew rescue, firefighting and other emergency response services to over 50 North Sea installations 24/7, 365 days a year.

The business has recently completed an in-depth independent study with Houlder Ltd to help determine the carbon emission reduction opportunities across its current 41-vessel fleet. The findings have highlighted the most effective green innovations for the firm to invest in over the next decade. Implementing the greenhouse gas reduction recommendations will help the business further its journey to net zero by 2040 while maintaining its competitive edge and delivering on the wider maritime sector’s decarbonisation objectives.

Emission reduction technology

North Star’s ERRVs typically operate on a 28-day duty cycle. They change crews, and bunker and load essential supplies, in port before travelling to the offshore installation, where they remain on standby until a relief vessel takes over. They then return to port to repeat the cycle. All our ERRVs operate on coordinated cycles, transiting between offshore installations to provide standby cover for approximately 24 to 72 hours at a time before moving on, spending a higher proportion of their time – and fuel – en route than most ERRVs.

Real-time measurement of fuel burn is central to understanding the implications of decisions on operational performance. A range of innovative emissions reduction technologies and approaches are being considered and assessed for their suitability on each vessel class in North Star’s fleet. These range from low-cost interventions to large equipment retrofit projects, and the decision on which route to take will depend on the assets and technologies adopted.

The company is also considering investing in a version of its AI software to help modernise and optimise its ERRV tonnage to further improve performance and reduce the cost of maintenance programmes.

High-performance hybrid-powered ships

North Star’s SOV design can be configured to include a heliport and accommodate up to 120 passengers and crew. Photo: VARD, courtesy of North Star

With the challenge of the country’s energy security well documented in recent months, the conversations around energy transition have changed tack. Although the oil and gas sector currently remains core to North Star’s business, we have now secured a significant market share within the offshore wind sector, which will be a major growth avenue for the organisation.

Last year, North Star was awarded four long-term contracts for its new hybrid-powered ship design. Taking the company into the renewables market for the first time, this vessel will provide comfortable hotel-style accommodation for the offshore wind technicians maintaining the wind turbines and sub-stations in field, with a centralised logistics hub to which they can go to work each day via a ‘walk-to-work‘ gangway, or transfer via a smaller daughter craft. The Service Operations Vessels (SOVs) are also configured to act as warehouses, and they handle cargo through side access hatches similar to those found on aeroplane holds.

The newbuild design is curated for shore-based power connectivity. The next step is an offshore connection, and North Star has recently joined an industry steering committee to progress in-field battery charging. As each SOV operates consistently within the same wind farm throughout its 10-year charter period, it could operate well on batteries once in-field charging stations are available. Its design includes embedded energy storage space which will enable conversion from diesel alone to a multi-fuel system, using an alternative feedstock such as methanol or hydrogen. Coupled with in-field fuelling and increased onshore and offshore automation, the development of zero-carbon power and propulsion technologies will achieve a faster decarbonisation journey for the company.

Digital revolution for SOVs

MO4’s decision support software will help to optimise efficiencies across North Star’s offshore wind fleet. Here the software shows the best access gate for a vessel attending an offshore wind turbine, according to sea and weather condition data. Photo: MO4, courtesy of North Star

As North Star is committed to identifying areas where sustainability can be improved, it is looking for new, innovative, ecological solutions which enhance sustainability across its business and its stakeholders.

During the concurrent 10-year campaigns for its initial four SOVs, the vessels will typically operate with between 50 and 75 crew and passengers on a 14-day duty cycle, half that of the company’s current ERRVs. The vessels will load up with cargo and supplies in port, and bunker fuel before transiting to the wind farm in UK waters. They will travel between wind turbines in dynamic positioning mode, and overnight they will be stationed on standby at a safe distance from field infrastructure, consuming less energy.

The company has invested in a digital twin and decision support software package to be installed on the four vessels. Developed by MO4 and believed to be the first of its kind used for the SOV market, the AI package will provide predictive maintenance support to help drive efficiencies across the fleet, including lower carbon emissions through reduced fuel usage. Aligned to North Star’s objective to aim ‘above and beyond’ with respect to SOV industry standards, MO4’s software will enable operations to be performed continuously within safety limits but without excess conservatism: a step-change in operational efficiency.

The digital solution will gather data from all four SOVs on influential areas such as weather fronts, workloads, work routes and drop-off schedules. The information is then collated and linked to the spatial model, to predict future behaviour. By monitoring the simulated data and harmonising across the fleet, the AI will help to increase in-field efficiencies further.

New SOV contracts on the horizon

North Star’s four offshore wind support vessels will be delivered to Lowestoft from early 2023. Photo: VARD, courtesy of North Star

The UK is leading the world in offshore wind generation, and every new turbine installed and feeding into the national grid takes the country one step closer to a CO2 emission-free future.

The potential for in-field charging or fuelling, as well as increased onshore and offshore automation and the development of zero-carbon power and propulsion technologies, could all support a faster decarbonisation journey.

Being at the forefront of sustainability solutions is a priority aim that North Star is passionate about. Collaboration with UK companies and technology partners remains key to the company’s success in driving change. Hiring local talent is also pivotal to this.

With a sharp focus on the carbon performance of its existing and new tonnage and what technologies might be available to make the required difference, the pathway towards net zero is becoming more and more transparent for North Star. Its decarbonisation strategy is critical to its business. It will not only ensure that its fleet of offshore vessels for the oil and gas industry is sustainable, but it will also increase its ability to win new business and build multiple new SOVs featuring green technologies simultaneously, futureproofing its tonnage and safeguarding jobs.

Matthew Gordon took over the helm of North Star Group as CEO in 2020, steering the business into a market-leading position and a new era of offshore infrastructure support for the UK renewables industry.