Offshore electrification: Exploring the externally powered FPSO concept

While the technology for offshore electrification has been available for decades, its adoption, at scale, has not progressed. Why is that the case?

During a panel discussion hosted by Petrobras at the 2025 Offshore Technology Conference (OTC), Jeremy Hall provided a look at the unique challenges and opportunities to electrify offshore floating facilities, explored the current state of the industry and discussed prospects in offshore electrification alongside other industry leaders.

As Jeremy noted in his conversation with Upstream at OTC, offshore “electrification is expanding rapidly, owing to rising demand in several growth markets” including “core electrification markets for Wood” like Norway, the Middle East, North America and South America.

What is driving the offshore industry toward electrification?

When considering the case for incorporating external power sources into Floating Production Storage and Offloading (FPSO) units, Jeremy noted that the primary business drivers include its reliability, security, ease of installation, environmental impact, project profitability, operating efficiency, and future operations and maintenance required.

Wood’s externally powered FPSO concept aligns to business sustainability goals by reducing greenhouse gases emitted through the elimination of gas turbines as the source for power generation. ​Operations and maintenance costs associated with rotating equipment​ are also reduced by replacing mechanical drive with electric motors and simplifying complex auxiliary support systems for gas turbines.

With more reliable energy and equipment, this leads to improved up-time as a result.​ Jeremy explained that we also find this concept to be future ready in its design development, supporting minimally manned or normally unattended facilities. It provides accessibility for robots to conduct inspection and monitoring activities, and minimizes the pre-investment required for instrumentation and automation.​ Additionally, with fewer personnel required onboard offshore facilities, operations costs are reduced, and safety is improved.

What offshore electrification solutions are being considered?

Hybrid systems, which combine electric and hydraulic components, were discussed as transitional solutions. One panelist explained that hybrid systems have been used effectively in various applications, reducing power consumption and infrastructure costs. For example, the current generation of subsea production tree systems, which use battery technologies, significantly lowers power consumption and enables full-scale electrification for production.

The panel also explored the cost efficiency of electrified systems, noting that long-term gas systems are ideal for electrification due to their simplicity and cost-effectiveness. Carbon capture and storage (CCS) projects are also perfect scenarios for electrification, given their long distances and simplistic tree designs.

Jeremy noted that with the FPSO concept, there are four potential sources of external power to consider - shore-based or onshore wind providing power from shore, offshore wind platforms, offshore micro-grid and other future offshore installations such as captive nuclear power.​

For static cables or fixed bottom facilities, both AC and DC solutions have been well proven in the offshore environment. For dynamic cables or floating facilities, AC solutions have been much further developed at this time, with a number of projects executed with higher technology readiness levels.

While HVAC and HVDC are far and away the most common technology approaches in transmission currently, there is increasing development around Low Frequency Alternating Current (LFAC) as a possible solution bringing the best features of HVDC and HVAC into a single option. LFAC can be used over long distances and keep the reduced waste heat and losses benefits of HVDC while also requiring smaller and cheaper AC equipment offshore. Regardless of the potential benefits of LFAC, the technology is not considered mature enough at this time. ​

What is preventing the widespread adoption of offshore electrification?

While electric systems offer cost reductions in control lines and hydraulic systems, comparing valve-to-valve costs remains challenging. There are also technological bottlenecks, particularly in subsea equipment, and the need for hybrid systems to overcome topside limitations.

There are three main bottlenecks for cost-efficient topside solutions: high-voltage cable supply chain issues, adoption challenges due to traditional power generation methods, and the initial investment required for new technologies.

When considering an externally powered FPSO, the key technical challenges to consider are the impacts on the overall electrical system design, facility layout, power and redundancy mitigations and alternative heat medium requirements. Jeremy explained that when we assess the changes required for the overall electrical system design, the things we need to address are transformers, switchgears, and configurations to handle high voltage (HV) power.​

When considering the retrofit of an existing design or a new design utilizing this concept, it might seem like removal of the typical power generation module, like gas turbine generators and waste heat recovery units would lead to ample space for layout considerations. ​This is not necessarily the case and the impact on the overall layout must be thoroughly reviewed both for equipment space and equipment removal if necessary. ​

In lieu of the generation module, additions might include a process module like a boiler and large heat pump and a power module like gas insulated substations, transformers, switchgears, and cables.​ When considering layout solutions, Jeremy advised to consider looking at reliable solutions with a smaller footprint than conventional designs.

Another challenge to consider is the loss of power and redundancy mitigations. Will it require battery back-ups? Wood has studied main power supplied by two high voltage distribution cables, one of which was redundant in case of issues with one of the cables. Emergency and essential generators driven by diesel are also a back-up option to consider.

There is also a need to find alternative heating medium options to Water Heat Recovery Units​ like electric heaters or heat pumps and boilers. These require more power​, and larger power requirements result in larger subsea cables, switchgear limitations, transformer capacity, and more.​

What changes are needed in the industry to further the adoption of offshore electrification?

The panelists discussed these barriers to adoption and other challenges, including the complexity of retrofitting aging facilities and the resistance to change within the industry. The need for training and competency development was a recurring theme. Training programs will be important in helping operators transition from hydraulic to electric systems. In addition, digital tools and feedback mechanisms can facilitate self-training and improve system interaction.

From the operators' perspective, ensuring system reliability and providing efficient training programs is especially important. One panelist mentioned that trust in the system is crucial for adoption, and operators must work closely with service providers to ensure operational reliability.

As with any new technology or solution, the panel agreed that it takes time for companies to accept the maturity and reliability of these electrified systems. Collaboration and standardization will be critical in overcoming the challenges facing offshore electrification right now. There is a need for industry-wide standards to enable plug-and-play solutions and reduce costs. The ongoing efforts to standardize equipment and interfaces will drive the future of these electrification initiatives.

At Wood, we are continuing to work with industry leaders and the supply chain to advance technologies to support these upcoming FPSO projects, as these larger loads will exceed limitations as defined in current regulatory requirements.​ Additional testing and certification of equipment and updated design standards will be required to ensure safe and reliable operations going forward.​