Biofuels are no longer an experiment in Dutch inland shipping. They are bunkered, used, and integrated into the daily operations of a fleet. For many ship owners and charterers, the transition is a seamless and problem-free one. For others, however, it brings to light technical and insurance questions that only become apparent once a voyage is underway.
Since the introduction of the blending obligation for biodiesel on 1 January, reports in the Dutch trade press, together with warnings from insurers such as EOC, indicate that parts of the inland shipping fleet are already facing operational friction, especially in colder conditions. These incidents are consistent with the established behaviour of Fatty Acid Methyl Esters (FAME)-based fuels, a proposed alternative to traditional fossil fuels, which contain higher levels of saturated fatty acids. This raises FAME fuel’s cold‑flow properties, increasing the likelihood of crystal formation and filter blockage at lower temperatures.
There have been reports of clogged filters, reduced engine performance, and in some cases, temporary loss of propulsion, requiring assistance. Unfortunately, these are not theoretical risks, but rather, operational realities during regular travel.
For insurers and brokers active in inland shipping, the pattern is becoming increasingly clear. A common misconception is that biofuels change the risk profile because they are new. This is untrue. Instead, it is because their operational characteristics differ from conventional fuels in ways that become relevant when things go south.
From bunkering to standstill
The inland shipping sector has been under pressure to reduce emissions under the 2019 Green Deal. An increasingly typical scenario is recurring: A Dutch dry cargo vessel bunkers a biodiesel blend containing FAME, the most frequently used form of biofuel in inland shipping. The fuel meets the specifications upon delivery, and the journey starts as planned.
Shortly after departure, however, filters begin to clog as deposits in the fuel system loosen. Engine performance deteriorates and power decreases. The ship needs to stop and requires assistance to reach a safe berth. These incidents occur immediately after the introduction of the blending obligation, which means that ships with different maintenance histories and technical conditions now operate under a structurally different fuel regime.
At low temperatures, fuel behaviour can further deviate from that of conventional diesel, increasing the risk of disruptions when systems are not fully prepared for them. This variability is not incidental: FAME quality and composition differ per production batch, meaning its behaviour—especially under winter conditions—can be unpredictable. Crystallisation, waxing and filter clogging may occur even when fuels meet formal specifications. What follows is not only a technical risk analysis but also an insurance question: assessing charterparty delays, distinguishing fuel quality from vessel condition, and reviewing whether available technical guidance was followed. The key question is no longer whether biofuel can be used, but whether the ship was prepared for it.
Why FAME is changing the rules of the game
FAME-based biofuels behave differently from conventional diesel. They have a cleaning effect on tanks and pipes, which can loosen long-term deposits. In addition, they absorb water more easily and are more sensitive to microbial growth. FAME also oxidises more rapidly when exposed to heat, light or oxygen, accelerating fuel degradation. In large inland vessels—where fuel circulation is often limited—this increases microbial growth and sludge formation, further raising the risk of filter blockage and fuel-flow disruption. In older fuel systems, or systems that have not been cleaned recently, this combination can quickly lead to problems.
IVR technical guidelines and industry bulletins have been pointing to these traits for some time. The difference now is in the scale. The use of biofuels has shifted from pilot projects to regular bunkering, on ships with widely varying ages, maintenance levels and operating profiles. What used to be a voluntary choice is now a regulatory reality, applied fleet-wide and in the middle of winter.
This distinction is crucial for insurers. Claims rarely hinge on whether the fuel was out of specification. Much more often it is about preparation, monitoring and the question of whether risks have been reasonably recognised and managed.
When a technical problem becomes an insurance issue
Loss of propulsion is rarely the end point. Assistance costs may follow, voyages can be delayed, and contractual obligations can come under pressure. Loss of propulsion is rarely the end point. Assistance costs may follow, travel can be delayed, and contractual obligations could come under pressure. Insurers often look beyond the immediate cause and consider the broader context, though this can vary by case. In evaluating such cases, insurers and brokers consider the immediate technical cause and the operational context, including maintenance history, documentation, and adherence to applicable guidance. This can vary by case.
Was the ship technically prepared for the use of biofuel? Were tanks and filters suitable? Were IVR or engine manufacturer guidelines taken into account? Was the fuel transition monitored? Inland shipping leaves little room for error. Short journeys, tight schedules and busy waterways mean that even a temporary power loss can quickly escalate into a commercial dispute.
Why the sector is joining forces
The decision by organisations such as KBN, IVR, NOVE and VOS to set up a central hotline for biofuel experiences reflects this reality. The aim is not to discourage the use of biofuels, but to get a better picture of where theory and practice diverge. Industry reports show that experiences differ: some ship owners report a smooth transition, while others experience operational setbacks. The reporting point is intended to distinguish between incidents and structural trends. According to industry watchers, FAME will likely remain the only immediately available biofuel option for inland shipping in the short term.
Sharing information helps stakeholders recognise patterns. For ship owners, it provides practical insight into how similar ships are performing and where extra precautions may be needed.
Financiers are also watching
These operational questions are not limited to insurers. Financiers also closely monitor how alternative fuels perform as they shift from policy ambition to daily practice.
In its analysis of the energy transition in inland shipping, Rabobank has emphasised that technical reliability, operational continuity and cost predictability are becoming increasingly important for financing decisions. When alternative fuels introduce uncertainty around downtime or unexpected costs, that uncertainty feeds directly into credit and investment assessments.
In this sense, recent engine incidents extend beyond the direct repair costs. They influence how comfortable insurers and financiers feel about supporting ships and operators during the transition.
What this means for ship owners and insurers
Biofuels are now part of normal business operations in Dutch inland shipping. Understanding the associated risk profile is therefore a matter of regular risk management, not an exception.
For ship owners, this means that the use of biofuels must be approached as a technical and operational choice, not merely as a purchasing decision. For insurers and brokers, it means asking the right questions early on and helping customers understand how operational choices affect coverage and conditions.
As a maritime insurance brokerage firm, much of our work is at the intersection of technical guidelines and operational realities. We support clients in assessing how ship condition, fuel choice and operations relate to insurance and financing expectations, and where small adjustments can prevent bigger problems down the road.
The energy transition in inland shipping will not be without friction. But with shared information, practical preparation, and a substantiated risk assessment, it does not have to be disruptive either.
