Marine environmental services and fuel testing solutions company CTI-Maritec on Wednesday (8 January) shared on why one of the most important testing parameters or properties of bio-marine fuel is energy content.

Owing to the composition of bio-marine fuels, the accurate measurement of Net Specific Energy (NSE) / Net Heat of Combustion to correctly gauge energy content of bio-marine fuels is key for efficient fuel management onboard ships: 

Introduction

Bio-marine fuel is widely adopted as a drop-in fuel to achieve the current emission requirements in the shipping industry. ISO 8217:2024 specification allows bio-marine fuels to contain up to 100% fatty acid methyl ester (FAME). The major production route of FAME is transesterification of vegetable oils, animal fats or used cooking oils with methanol using alkaline catalysts. The ISO 8217:2024 version has included additional test parameters to measure FAME content, energy content and oxidation stability for bio-marine fuels.

Accurate Net Specific Energy (NSE) assists with efficient fuel consumption management

In this newsletter article, we review why one of the most important testing parameter or property of bio-marine fuel is Energy Content. Accurate measurement of NSE for energy content of bio-marine fuels is essential for efficient fuel management onboard ships with respect to:

• Fuel consumption
• Voyage planning
• Operating cost
• Machineries or equipment performance
• Emission & environmental implications

Why accurate testing of Energy Content is an essential test parameter for Bio-marine fuel

Marine fuel containing FAME typically has lower energy content compared to conventional marine fuels.

The heating value of a fuel is the total energy released as heat when a fuel undergoes complete combustion with oxygen under standard conditions. The chemical reaction is typically a hydrocarbon reacting with oxygen to form carbon dioxide, water and heat as shown in the equation below:

Hydrocarbon + Oxygen à Carbon Dioxide + Water + Heat Released

Conventionally, NSE of marine fuels (which consist of predominantly hydrocarbons from petroleum sources) is calculated using a formula specified in Annex of ISO 8217 (Annex J of ISO 8217:2024) with acceptable accuracy. For marine fuels containing FAME, the NSE cannot be calculated using the formula specified in Annex J of ISO 8217:2024 and shall be measured using ASTM D240 method. FAME molecules contain the Carbonyl group and Ester bonds as shown in Figure 1 below and do not consist purely of carbon and hydrogen atoms.

Figure 1: An Ester of a Carboxylic Acid

The density of potential energy of a hydrocarbon is determined by the number of carbon to hydrogen bonds that can be replaced by oxygen to carbon (CO2) and oxygen to hydrogen bonds (H2O), in other words, the amount of energy released is dependent on the oxidation state of the carbons in the hydrocarbon. For marine fuel containing FAME, the FAME molecule itself contains oxygen atoms in the Carbonyl group and Ester bond. The Ester group of FAME has a carbon forming 3 bonds with oxygen atoms, this means esters are more oxidised than hydrocarbons and esters release less energy content when compared to hydrocarbon since higher oxidation reactions are needed for hydrocarbons.

The paragraphs above explain the reasons marine fuel containing FAME typically have lower energy content compared to conventional marine fuels, which consist of predominantly hydrocarbons and the calculated formula for NSE is not applicable to marine fuel containing FAME.

According to ASTM D240 test method, heat of combustion is determined by burning a weighed sample in an oxygen bomb calorimeter under controlled conditions. The heat of combustion is computed from temperature observations before, during, and after combustion, with proper allowance for thermochemical and heat transfer corrections. The average of gross specific energy (GSE) or gross heat of combustion, and NSE or net heat of combustion of MGO, VLSFO, HSFO and Bio-marine Fuels are tabulated in Table 1 below:

Note: The average GSE and NSE for each of the fuel types was obtained from at least 50 samples.

Based on Table 1, bio-marine fuel B30 has 8% lower energy content when compared to MGO. The energy content of bio-marine fuel will become lower when the FAME content is higher.

Energy content of marine fuel containing FAME shall be determined by ASTM D240 method and cannot be calculated using the current NSE formula, which is commonly used for the conventional marine fuels.

Note: The full article by CTI-Maritec can be found here. 

Photo credit: Louis Reed from Unsplash
Published: 9 January, 2025

Steve Bee, Commercial Director of marine fuels testing company VPS, in December 2024 elaborated on the increase in demand in biofuels based on the number of samples VPS laboratories are receiving and its biofuel testing innovations: 

Introduction

It's very apparent, global shipping’s drive to decarbonise is well underway. The ship-building profile is changing dramatically, highlighted by the 2023 order book showing 539 new builds capable of running on low-to-zero carbon fuels, being ordered. Looking at Jan-Sept 2024, 49% of the gross tonnage on order were for vessels configured to be alternative fuels ready, with this specific order book growing by 24% year on year. It's obvious that shipping is keeping its options very much open and looking for as much flexibility as possible, when it comes to the fuel choices for its ships.

The industry currently bunkers 230 Million mt of fuel per year. Burning this fuel equates to emissions of 716M mt of CO2-equivalent, as the majority of the fuel burnt continues to be traditional fossil fuels. This is supported by studying VPS fuel sample receipt for 2023 which was, 54% VLSFO, 30% HSFO, 14% MGO and 1% each for ULSFO and Biofuels.

However, the list of environmental legislation and directives to reduce emissions from shipping is ever-increasing in order to reduce SOx, NOx, Particulate Matter, CO2, Methane and other Green House Gases.  It is this regulatory demand which is driving the developments of numerous alternative low-to-zero carbon fuels for marine use.

But it is biofuels, which currently offer an attractive and immediate path to CO2 reduction. As a “drop-in” fuel option, using existing delivery, storage, fuel-transfer and engine operation processes, biofuels provide a decarbonisation solution, with minimal change.

VPS has been and continues to be, at the forefront of fuels research & development and continuing our innovative development of test methods for such fuels. We are working on numerous biofuels projects with the Global Centre for Maritime Decarbonisation (GCMD), sea trials with ship owners and operators, plus working with both fuel suppliers and additive manufacturers to assist in their product developments.

Biofuels

So what’s the biofuels story today? We are seeing an exponential increase in demand based upon the number of biofuel samples we are receiving in our laboratories, linked to the actual metric tonnes of biofuel being delivered per stem. Between 2021 to 2023 biofuels samples received by VPS increased from 70,000mt to 558,000 mt delivered. This year biofuel samples received by VPS will surpass 700,000 mt of biofuels delivered.

Singapore exceeded 2023’s delivered quantity at the half-year point of 2024 and Asia Pacific more than trebled biofuel bunkerings vs last year, as we go into the final quarter of 2024.

Europe is on track to do 40% more than last year if delivery rates continue as they have been.

2024 has seen lower percentage bio-components, ie B10-B30 increase in demand, whilst a significant reduction in higher bio blends, ie B100.

This is likely to be price-driven, as the amount bio content of the fuel is at its premium versus traditional fuels. B20s running around 17% more and B30s running at 23% more than conventional fuels.

For FAME-based biofuels, there are six key quality considerations to take into account.

Firstly, Oxidation Stability, as FAME can oxidise and destabilise very quickly. As FAME destabilises, it becomes considerably darker in appearance, more viscous and much more acidic. VPS utilise three tests to establish a fuel’s level of stability: The Rancimat test, which is a deliberate aging test, where we look to implement a “traffic-light” assessment of Green for a > 8 hours result, Amber for a 5-8 hour result and Red for a<5 hour result. We can then use the Iodine Value test to measure the degree of unsaturation and potential reactivity of the biofuel and thirdly, the Polyunsaturated Fatty Acid content determination via GC, to measure Linoleic Acid and Linolenic Acid levels.

FAME has poor cold-flow properties and so we use the traditional tests of cloud point, cold-filter plugging point and pour point to determine these. Except when the blend is with a dark fuel, then we use the proprietary VPS Wax Appearance Temperature Test.

FAME can be very corrosive, so we test for Total Acid Number, but also undertake Copper and Steel corrosion testing as FAME can be corrosive towards certain surfaces.

As FAME loves water, this can create a breeding environment for bugs and so Bacteria/Yeast/Fungi testing is a key test to monitor the level of microbial activity.

Knowing the calorific value is essential and with fossil fuels this can be determined by a calculation within ISO8217. However, due to the higher oxygen content of FAME, this calculation is inaccurate for biofuels where the FAME content is greater than 10%. and therefore, the laboratory test ASTM D240 must be used to determine the energy content.

Many test to determine the renewable content of biofuel have poor repeatability and reproducibility. To overcome this, VPS have modified EN14078 to produce a much more accurate determination of renewable content, which is and will be, so key in ensuring correct levels of carbon taxation is paid by vessels.

Note: The full article by VPS can be viewed here. 

Related: GCMD, VPS provide innovative means to detect fraud in sustainable biofuel supply chain

Photo credit: VPS
Published: 6 January, 2025

Marine fuel quality and surveying firm VPS on Wednesday (18 December) announced the appointment of Steve Laino to the role of Managing Director for the Americas. 

In this role, Laino will apply his experience and knowledge to deliver complete value-chain solutions for fuels, lubricants and decarbonisation in the region. 

Laino joined VPS having held C-suite and leadership roles as a ship owner, broker, entrepreneur and advisor across multiple sectors and markets in the global supply chain. 

Most recently, Laino has applied his subject matter expertise and in-depth understanding of the emerging emissions and alternative fuels sectors in his role as Global Head of Environmental Solutions with Poten & Partners/BGC Partners. 

He has a strong background in shipping, having graduated from the US Merchant Marine Academy at Kings Point, sailed as an officer in the US Merchant Marine and served as Lieutenant Commander in the US Naval Reserve.

Dr. Malcolm Cooper, VPS CEO, stated: “The maritime industry is changing fast with ambitious emissions targets and decarbonisation requirements driving the introduction of new technologies and fuels into the market.”

“In this dynamic landscape, we are very pleased to have Steve on board to lead delivery of all VPS services to customers in the Americas and help them optimise their operations by understanding which new fuels to use and how to adapt to these sustainable business drivers and meet new regulations.”

Steve Laino, stated: “Industries around the world are witnessing a paradigm shift in the energy products that power them and the environmental regulations that govern their stakeholders’ compliance. An increased need for transparency and traceability of energy sources and production methods will grow to be a primary driver of successful business strategies.”

“Testing, verification, certification, data-supported analysis and the ability to easily access and disseminate critical information from these sources are quickly becoming required tools of the trade.”

“For decades, VPS has reliably provided and evolved their services to the maritime, power generation and wind sectors. In response to the evolution of energy products and the impact on businesses in and adjacent to the supply chain, VPS has invested in new digital platforms, testing capabilities and advisory capacity to meet the challenges faced by its customers.”

“I am very pleased to join VPS to lead and grow their business in the Americas.  I look forward to working closely with our team to gather and provide valuable decision-making information to our clients, yielding the flexibility and foresight needed to navigate the new commercial, operational and technical challenges before us.”

Photo credit: VPS
Published: 19 December, 2024