TNO begins yearlong test of biodiesel blends in Dutch inland-shipping sector

Photo: TNO

Dutch inland shipping can achieve a significant CO2 reduction in the short term by blending fatty acid methyl esters (FAME), also known as biodiesel, but there are some skeptics.

In order to objectively map out any risks associated with long-term use and to provide the sector with clear information about safe application, TNO—an independent, nonprofit research organization based in the Netherlands—is starting a broadly supported one-year practical test.

As an important link within the Dutch transport sector, inland shipping in the Netherlands also has the task of decarbonizing.

Under the Renewable Energy Directive (RED III), inland shipping must achieve a CO2 chain reduction of 14.5 percent by 2030.

At present, this sector emits 1.6 million metric tons of CO2 annually, which is equivalent to 550,000 passenger cars.

Compared to total freight transport including road and rail, inland shipping has a share of 13 percent in CO2 emissions.

Although fully battery-electric sailing and the use of sustainable hydrogen and methanol are also being pursued for the future, these are not short-term solutions.

Biobased diesels such as FAME and hydrotreated vegetable oil (HVO), also known as renewable diesel, are available sooner and are an affordable “interim” solution, according to TNO.

FAME in particular can ensure a rapid CO2 reduction in inland shipping at a lower cost than most other options.

“FAME is a biofuel made from fats and oils and is often produced from residual products, such as reused cooking oil, but also animal fats, or vegetable oils such as palm oil or rapeseed,” said Jesse de Boer, a scientist at TNO who specializes in biofuels. “The fatty acids are converted into FAME by means of esterification, which has similar physical properties to diesel oil. FAME is almost always mixed with diesel, in various mixing ratios, from 15 percent to 30 percent.”

Availability is a point of attention.

“The Renewable Energy Directive strongly focuses on the development of advanced, so-called Annex IXA, raw materials for biofuels such as FAME,” de Boer added. “These are often residual products from agriculture and forestry. These fuels may not be at the expense of food production, and the well-to-wheel emissions may not be too high. At TNO, we are working hard to map this out. FAME offers significant emission gains when used on a large scale—eight times less CO2 emissions per kilogram compared to diesel.”

The potential emission gain with large-scale use of FAME is considerable.

“Suppose you blend 30 percent FAME for the entire inland-shipping sector, then you can reduce CO2 by approximately 26 percent,” de Boer said. “It should be noted that not all inland vessels can sail on FAME. For example, the newer Stage V vessels are often less suitable, and the blend percentage must be limited to, for example, B10 or B20.”

According to de Boer, FAME is still interesting because this biodiesel can be used quickly and with limited investments.

“Certainly, in a sector where the technical and economic lifespan of equipment is long,” de Boer said. “Moreover, FAME is available more quickly and is cheaper than HVO, which has a more complex and expensive production process.”

Despite these advantages, inland shipping does not yet seem to be fully convinced of the use of FAME.

“Safety and reliability are of great importance in inland shipping,” de Boer said. “During the first tests with FAME, the trade association KBN drew up a reporting form so that ship owners could report problems. A number of issues emerged from this, such as clogged fuel filters and bacterial growth. But the most worrying thing was that ships came to a standstill. That caused fear, especially because the cause was unknown. There was no information about the initial situation. What was the condition of the ship, were the tanks clean, was the engine not already contaminated? Was there something wrong with a certain fuel batch? Many questions to which we do not yet have a clear answer, hence this practical test.”

Eight ships will sail for a year under the supervision of TNO on various higher FAME blends, up to B30.

The research, commissioned by IenW, must provide insight into the compositions and under which conditions this biodiesel works best on inland vessels.

“With this test, we will accurately map out the starting situation, keep track of what it is like to sail on FAME, and we will soon know exactly which technical and operational measures are needed to be able to sail smoothly on this new fuel,” de Boer said. “In addition, the test must show whether a specific fuel-quality standard is needed for a certain blend for inland shipping.”

The inland-shipping sector is closely involved in the research with the cooperation of KBN, NOVE/Stichting VOS, VEMOBIN, MVO, and VT-group, but also of engine suppliers and the insurance industry. TNO is responsible for the coordination and reporting of the test and will also analyse fuel samples.

“A monitoring form is filled in every time these ships bunker,” de Boer explained. “In this way, we collect information about the oil-change interval, the operating hours of the engines, the bunkered volumes and the frequencies with which filters need to be replaced. We also inspect fuel filters for deposits or contamination. In addition, external parties regularly carry out fuel analyses. In the current FAME standard (EN 14214), some critical substances are not limited. With this test, we also keep an eye on those substances.”

The yearlong project will take into account all four seasons.

The results are expected to be published at the end of 2025.

The three fuel suppliers involved in the trial, FincoEnergies, OK Slurink and Den Hartog, have been testing ships on higher FAME blends for some time now and expect few problems.

Initial studies have shown, for example, that the lubricating-oil change period is slightly shortened with FAME.

They are also looking at oxidation stability and at bacterial growth and clogged filters.

In addition, FAME tends to attract water.

Based on these experiences, these suppliers estimate the risks to be low.

“With this trial, we can objectively determine safety,” de Boer said. “At TNO, we believe it is extremely important to seize all opportunities to make things more sustainable. In the future, we must of course continue to make efforts for battery-electric sailing and the use of hydrogen, methanol and eFuels. But for the short and medium term, I see FAME as an essential tool for making inland shipping more sustainable.”