Baturalp Alkan: Hidden Bunker Is Shipping’s Most Overlooked Financial Risk

Global shipping moves nearly 90% of the world’s trade, making bunker fuel one of the largest operating costs for every vessel. Yet one of the industry’s most significant financial risks continues to receive far less attention than it deserves: hidden bunker.
During years of independent bunker survey operations, I have learned that bunker discrepancies rarely originate from a single event. They are usually the result of operational inconsistencies that remain unnoticed until a detailed technical investigation is carried out.

A modern bunker investigation is no longer limited to measuring fuel onboard. It requires a comprehensive assessment of voyage performance, fuel consumption, engine efficiency, weather conditions, operational records, tank calibrations, and logbook consistency. Every voyage leaves technical evidence—if you know where to look.
The findings from our international operations over the past month clearly demonstrate the scale of this issue.
During independent bunker survey operations conducted in multiple countries, our team identified significant quantities of previously unaccounted bunker fuel:

Brazil (Santos): +23 MT
Poland: +35 MT
The Netherlands: +70 MT
Algeria: More than +100 MT across several vessels
South Korea: +40 MT
In total, more than 268 metric tonnes of hidden bunker were identified within a single month.

These figures were not discovered through routine tank soundings alone. Every case involved a comprehensive technical investigation, including bunker quantity verification, voyage performance analysis, speed and consumption calculations, weather evaluation, engine performance assessment, logbook verification, and operational consistency checks.

The conclusion is clear.
Hidden bunker is not an isolated incident, nor is it simply a measurement issue. It represents a recurring operational and commercial risk that can significantly impact shipowners, charterers, commodity traders, and marine insurers.
As fuel prices continue to represent one of shipping’s largest operating expenses, even relatively small discrepancies may result in substantial financial losses. Independent bunker investigations have therefore become an essential risk management tool rather than a routine survey service.
At Vals Marine Survey, our objective extends beyond measuring fuel onboard. We combine engineering expertise, operational experience, and independent analysis to identify discrepancies before they become commercial disputes.

Our responsibility is not only to determine how much fuel is onboard—but to explain why the figures differ, where the discrepancy originated, and how it can be technically verified.
Hidden bunker is not simply fuel that cannot be seen.
It is hidden financial exposure.
Identifying that exposure before it turns into a commercial dispute is where independent bunker investigation creates its greatest value.

About the Author
Baturalp Alkan is the General Manager of Vals Marine Survey and is recognized for his expertise in independent bunker quantity surveys, off-hire bunker investigations, voyage performance analysis, and hidden bunker detection. Through international survey operations across Europe, Africa, Asia, and South America, he supports shipowners, charterers, traders, and marine insurers with independent technical assessments and commercial risk mitigation.