Dimitri de Gunzbourg, chief technology officer at Charge Offshore (by MJR Power & Automation), explores marine fleet electrification as a primary route for decarbonising the offshore wind sector, and discusses the need for charging infrastructure integration to accelerate the transition.
Dimitri de Gunzbourg
Offshore wind has become one of the great engineering success stories of the energy transition. Turbines are growing in scale and efficiency, installation techniques continue to advance and entire supply chains have matured at remarkable speed despite geopolitical setbacks. Yet, beneath progress lies a contradiction that’s hard to ignore. While offshore wind generates clean electricity, the vessels that build, operate and maintain these assets remain largely dependent on diesel.
Fleet electrification is emerging as one of the most important, and solvable, engineering challenges facing offshore wind, and the success of this transition will be driven by the practical application of power systems engineering, safety-led design and infrastructure planning.
The hidden carbon cost of offshore operations
Operations and maintenance (O&M) fleets are the backbone of offshore wind. Crew transfer vessels (CTVs) and service operation vessels (SOVs) move technicians, tools and components between ports and wind farms, usually operating in continuously in harsh metocean conditions. Despite the clean power generated by the turbines they serve, most of these vessels still rely on marine gas oil (MGO)-powered engines.
From an engineering perspective, this presents a critical inefficiency that’s hard to justify. Diesel propulsion creates emissions, noise, vibration and requires significant ongoing maintenance, all while operating alongside assets that generate abundant renewable power. As offshore capacity scales rapidly across the UK and Europe, the cumulative emissions and operating costs of these fleets are rising starkly in parallel.
Fleet electrification offers a clear technical pathway to address this imbalance, but only if it’s supported by infrastructure capable of delivering reliable, high-power charging at sea.
Vessel electrification: from theory to reality
Electric and hybrid vessel designs are no longer purely theoretical. Over the past few years, a growing number of e-CTV and e-SOV concepts have moved through trials and early deployment. Advances in battery energy density, power management systems and marine-grade electrical architectures mean that electric propulsion can now meet the needs of most offshore wind operations. With the cost of batteries continuing a downward spiral, the CAPEX requirements for electrified O&M fleets will also soon reach parity with their fossil fuel-powered counterparts.
However, propulsion is only one side of the equation. Without dependable charging infrastructure, electric vessels are constrained by range, downtime and operational flexibility. Shoreside charging, while important, is insufficient alone for offshore wind, where vessels may operate far from port and remain at sea for extended periods.
Offshore charging as a power systems challenge
The main challenge of charging at sea is to safely and efficiently transfer megawatt-scale electrical power from offshore wind assets to moving vessels in all-weather conditions, without compromising safety or performance.
In-air offshore charging systems mounted on turbines, substations or fixed and floating structures, avoid many of the durability and maintenance issues associated with existing waterline or buoy-based solutions. By remaining clear of the splash zone, these systems reduce corrosion risk and greatly simplify inspection and servicing.
From a design standpoint, safety is paramount. Hands-free connection and disconnection, overload protection and fail-safe operation in the event of power loss are essential requirements for routine offshore use. These systems must function predictably in high winds, heavy seas and limited visibility, while integrating seamlessly with existing vessel power management systems.
At Charge Offshore, a spinout from MJR Power & Automation, we’ve brought two charging systems to market which meet these requirements: the Aquarius Eco, designed for smaller E-CTVs, and its larger E-SOV counterpart, Aquarius Plus. These systems offer fully automated and hands-free charging, ensuring crew safety, reliability and performance even in challenging offshore environments.
Both systems are modular and designed for rapid integration into offshore assets. Crucially, this means that installation requires only minimal structural modification, easing their inclusion in the design stage of new wind farm developments.
Designing wind farms for electrified operations
A significant trend in offshore power is the new recognition that charging infrastructure should be considered at the wind farm design stage. Designing assets to be “charger ready” with space, structural provision and electrical interfaces planned in from the outset, can be achieved with minimal additional complexity or capital expenditure.
This approach reflects a broader systems engineering mindset. Offshore wind farms are fast evolving into multi-functional energy hubs. Supplying power to vessels, enabling cleaner operations and supporting future energy services all become part of the same design philosophy.
Regulation is accelerating the timeline
While the CAPEX and decarbonisation case for fleet electrification is strong, regulation is sharpening the focus. The expansion of the European Union Emissions Trading Scheme (ETS) to include offshore vessels from 2027 is a clear signal of what lies ahead. As discussions continue around extending the scheme to smaller vessels, including many CTVs and SOVs, operators face increasing exposure to carbon costs. Costs which can be alleviated by transitioning to electric.
For wind farm developers, this reinforces the need for future-proof solutions. Electrification supported by offshore charging infrastructure offers a direct route to significant OPEX and emissions reduction at source, rather than relying on offsets or transitional fuels with their own logistical hurdles, efficiency losses and prohibitive costs.
What does the future hold for fleet electrification?
In the coming years, several trends are expected to define the offshore wind operational landscape:
First, electric and hybrid vessels will move beyond pilot projects into routine service, supported by proven charging systems operating at scale. Second, offshore charging will become a standard consideration in new wind farm developments, particularly in regions with ambitious capacity expansion plans. Third, collaboration between wind farm developers, vessel owners and fleet operators will deepen, driven by the shared need for fully integrated systems rather than deploying isolated technologies.
Ultimately, the focus will shift from whether fleet electrification is possible to how quickly and effectively it can be implemented. By electrifying O&M fleets and embedding charging capability into offshore assets, the industry can close one of the remaining gaps between clean energy generation and decarbonised operations.
For more information on Charge Offshore and its Aquarius Eco and Aquarius Plus charging systems, visit: www.chargeoffshore.com.
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