Biofuels: an attractive alternative, but there is much to learn

Among issues to be aware of, he cited FAME (Fatty Acid Methyl Ether)’s greater acidity and viscousness, poor long-term stability, higher levels of microbiological activity, poor cold-flow properties, and a tendency towards corrosivity. And in an observation made by other experts, he added that ship operators needed to take into account biofuels’ lower energy content compared with conventional fuels, leading to “less bang for the buck”.

However, none of these concerns should obscure the fact that most operators, he said, do not have major problems with biofuels, provided they attend to the basics. These included conducting their own fuel checks, cleaning tanks and maintaining a dialogue with OEMs and their preferred laboratory.

Biofuels are not new

As MAN Energy Solutions senior engine specialist Klaus Petersen pointed out, biofuels (or “non-standardised” fuels) are far from new, citing the energy giant’s experience with a wide variety of them since the mid-1990s. Ticking off some of these, he cited FAME, crude palm oil, vegetable oil, used cooking oil and other wastes, tallow, cow fat, stearin and coconut oil. With all that experience behind it, MAN Energy Solutions has drawn up valuable guidelines for biofuel operation that take into account the ISO 8217 fuel standard.

For instance, reflecting Mr Mollet’s comments about the importance of underwriters and risk managers, Mr Petersen said that insurance, warranties and contracts may include clauses on compliance with ISO 8217. And in an example of standards lagging the biofuels industry, he noted that the equations in ISO 8217 used for calculating specific energy are not valid for biofuels, or even for blends of biofuels. Nor is there an analysis standard for measuring FAME content above 7% in a blend.

“It is vital to collaborate with bunkerers over the precise nature of the biofuel”

On the all-important issue of operational considerations, MAN Energy Solutions advises that sealing materials (elastomers) and other materials in the fuel oil auxiliary system are compatible with biofuels or blends. And reinforcing the observations of others on the panel, Mr Petersen said: “Know what is bunkered.” He listed viscosity, cold-flow properties, acid number and value, ash content, and chemical elements among others. And finally, in the furtherance of sustainability, he urged operators to favour biofuels made from sustainable feed stocks and production methods.

That is exactly what biomass-based Mash Energy, a spin-off from the Technical University of Denmark, is aiming for, as Dr Krishna Chakravarty, head of R&D at the Indo-Danish producer of carbon-negative biofuel, explained. “Shipping doesn’t need diesel-like products,” he said. Engaged in the dual goals of carbon removal and energy generation, Mash Energy makes bio-oil among other carbon-negative energy from local biomass residues by using the processes of pyrolysis and gasification. The residue is biochar, a ‘soil amendment’ that actively absorbs CO2 from the atmosphere.” With one manufacturing site in operation, Mash Energy is aiming for many more through a system of special purpose vehicles.

In a revealing series of polls and questions, the attendees predominantly described their level of experience with biofuels as moderate or intermediate, while an overwhelming majority believe they would only “possibly” be a mainstream option in future, and that it was unlikely there would be enough biomass for shipping’s needs in the near future.

Biofuels can be blended with traditional fuels to lower greenhouse gas (GHG) emissions. Hapag-Lloyd container ship Afif bunkered 2,000 metric tonnes of B24 biofuel supplied by TotalEnergies Marine Fuels at the Port of Singapore in January. Based on a well-to-wake assessment, this B24 biofuel blend is anticipated to reduce GHG emissions by 20%, as compared with conventional fuel oil.