Connect with us

Scrubbers

DNV GL Interview: Study on scrubber operation challenges

DNV GL speaks with Fabian Kock, head of Environmental Certification at DNV GL on study conducted of owners’ experiences with installing and running scrubbers.

Admin

Published

on

5d5342cfa4b5e 1565737679

Classification Society DNV GL on Thursday (16 January) published an interview conducted by the organisation with Dr. Fabian Kock, Head of Environmental Certification, DNV GL regarding a study it has conducted with shipowners on the challenges in installing and operating scrubbers:

The Global Sulphur Cap is in force now and many owners have opted for Exhaust Gas Cleaning Systems (“SOx scrubbers”) to achieve compliance. DNV GL conducted a study to learn about owners’ experiences of installing and operating scrubbers. The insightful results can help the industry avoid some of the challenges.

Dr Fabian Kock joined DNV GL in 2009 after studying mechanical engineering in Hamburg, Sydney and Chennai and subsequently gaining experience in the field of engine development. In his current position as Head of Environmental Certification at DNV GL, his section is responsible for environmental certification of marine diesel engines, marine exhaust gas aftertreatment systems such as SCR catalysts and scrubbers, and certification of the energy efficiency of ships.

DNV GL: What is the current situation in the scrubber market? Will all scrubbers be installed in time to ensure compliance with IMO’s Global Sulphur Cap?

FK: We know that there is currently a four- to five-month backlog of vessels that should have been retrofitted by the end of last year. The number of vessels that need to be retrofitted has accumulated so it will probably take until April or May to complete all scrubber installations.

DNV GL: What are the reasons for the backlog?

FK: The reasons are manifold. Material shortages and limited yard capacity are the biggest issues. For example, there is only a limited number of manufacturers of GRE pipes in China where most scrubbers are installed. Designers and yards have a high workload of retrofit installations, and lack of staff has doubled the installation time at yards from 40 to 80 days. At the same time, class societies had to cope with a higher number of vessels needing to be surveyed during peak times. Therefore, DNV GL started to offer remote surveys for exhaust gas cleaning systems on sister ships.

DNV GL: What do owners need to know when their installation is delayed?

FK: From 1 January 2020 vessels must run on very low-sulphur fuel oil (VLSFO) or with scrubbers. If a scrubber has not been installed in time, operators need to switch to VLSFO until a scrubber has been installed and approved. An even harder deadline is 1 March 2020: from this date on, even the carriage of high-sulphur fuel oil (HSFO) on vessels without scrubbers is prohibited. This means that operators of ships not equipped with scrubbers must remove all HSFO from board and clean the tanks. They will only be allowed to carry HSFO again and use it as fuel after installing a scrubber system.

DNV GL: What needs to be considered before installing a scrubber?

FK: Planning is an important factor because it takes time. In the case of a newbuilding project, the fuel price is the crucial factor that decides whether to opt for a scrubber or VLSFO. At a price difference of about 200 USD per tonne of fuel, scrubber installation is attractive. But long-term precise price predictions are very difficult. Furthermore, choosing the right material and coatings to avoid corrosion of the piping is essential as well. GRE pipes with a diameter of up to one metre need supporting struts to avoid damage when litres of heavy wash water flushes through them.

DNV GL: Based on the recently published operational experience study, what are the main challenges with scrubbers during operations?

FK: Leakage and corrosion of SOx scrubber overboard pipes have been reported. To account for that risk, DNV GL has updated its rules and requires annual thickness measurements on various overboard pipes and spool piece designs. Sensor failures are also a big concern, and adhering to planned maintenance intervals is of utmost importance. When a sensor fails, the control system can get the wrong data and cause an incorrect or unnecessary operational response. Misleading sensor data can also falsely suggest that emissions are within limits and only when the emissions are checked by an authority will this be detected. In that case, the operator may get a penalty in the form of a high fine; in some ports the responsible officer might even be arrested. Some EU and Chinese ports have fitted sensors at the quayside, and on some occasions, PSC officers equipped with a handheld sensor have boarded to check emissions. Drones are also used in some areas to measure vessel emissions.

DNV GL: What can vessel operators do to avoid or overcome these challenges?

FK: Adherence to the planned maintenance intervals and concluding a service agreement with the sensor manufacturer helps a lot. Keeping spare parts on board is also vital to avoid prolonged scrubber outages. Furthermore, a preliminary test of the control system can help avoid failure during operation as well as costly repairs or reinstallations. DNV GL already offers hardware-in-the-loop testing for these control systems at the workshop to check how the control system behaves in various situations and extreme conditions, such as very low or high temperatures, which can be simulated during these tests as well.


Photo credit and source:
DNV GL
Published: 7 February, 2020

Continue Reading

ECA

VPS examines North-East Atlantic ECA on current bunker fuel mix and testing

Impact of this new ECA, will not only affect bunker fuel selection and testing, but it will also require a review of, voyage planning, bunker procurement and scrubber strategy, amongst others.

Admin

Published

on

By

RESIZED VPS logo

Steve Bee, Group Marketing and Strategic Projects Director, and Emilian Buksak, Decarbonisation Advisor of marine fuels testing company VPS, on Wednesday (8 April) highlighted MEPC 84 approved a new emission control area (ECA) covering the North-East Atlantic Ocean, with agreements reached on adopted amendments to MARPOL Annex VI. 

The new ECA, which will become the world’s largest emission control area, will be implemented on 1st September 2027

In a recent article, VPS outlined how VPS testing, data, CEM systems and advisory services can support vessels in both their operational and compliance challenges associated with this new ECA:

The recent International Maritime Organisation’s (IMO), Maritime Environmental Protection Committee (MEPC) meeting in London, had its main focus on setting binding greenhouse gas emission reduction targets for the global shipping sector. In keeping with the Committee’s continuing drive to decarbonise shipping and reduce the pollutant emissions from the global fleet, one major outcome from the MEPC-84 meeting was the approval of a new emission control area (ECA) covering the North East Atlantic Ocean, with agreements reached on adopted amendments to MARPOL Annex VI.

This new ECA, which will become the world’s largest emission control area, will be implemented on 1st September 2027, with the ECA requirements taking effect on 1st September 2028. It will cover the territorial seas and exclusive economic zones of Greenland, Iceland, the Faroe Islands, Ireland, the United Kingdom, France, Spain and Portugal, extending up to 200 nautical miles from their baselines:

VPS examines North-East Atlantic ECA impact on current bunker fuel mix and testing

A key advantage of the new NE Atlantic ECA is that it will close the gap between the existing ECAs in the North and Baltic Sea, plus the Mediterranean, creating an almost continuous zone of reduced shipping emissions. It will also connect to the newly approved ECAs in the Canadian Arctic and Norwegian Sea, which are scheduled for implementation in 2026 and 2027 respectively. Together these ECAs will cover almost half of all Arctic coastal waters, improving air quality, by reducing SOx, NOx and Particulate Matter (PM), protecting  public health, and reducing the environmental impacts from shipping.

The sulphur limit for the marine fuels allowed to be burnt within this new ECA will reduce from the current 0.50% to 0.10%. This will force vessels to use either effective abatement technology (scrubbers), or alternatively burn marine distillates, ultra-low-sulphur fuels (ULSFOs), or biofuels with a sulphur content of less than 0.10%.

Without doubt this new ECA will cause a significant change to the current fuel mix, probably on an even greater scale than was witnessed with the introduction of the Mediterranean ECA back in May 2025.  The fuel mix in the Mediterranean Pre-ECA implementation was,  53% VLSFO, 28% HSFO, 16% MGO, 2% ULSFO and 1% Biofuels. But from the 1st May 2025, the fuel mix changed to, 30% VLSFO, 29% HSFO, 30% MGO, 8% ULSFO and 4% Biofuels.  

So, in terms of actual tonnage, the Mediterranean ECA witnessed a decrease in VLSFOs by 23%, whilst MGO usage increased by 107%. At the same time, ULSFO and biofuels supply increased 4-fold.

Regarding fuel quality within the Mediterranean post-ECA implementation, MGO off-specification rates increased to 4%. However, the most worrying off-specification rates were for ULSFOs which saw a 10-times increase from 2% to 20% from the start of the ECA, with the main off-specification parameters being pour point, sulphur, TSP, CCAI, water and viscosity.

Therefore, it is fair to assume we’ll witness a similar dramatic fuel mix change upon the implementation of the NE Atlantic ECA, with possibly similar fuel off-specification issues, highlighting the continuing need for proactive fuel testing to protect vessels, crew and the environment.

Whilst the focus on fuel quality is essential, the multi-pollutant nature of this new ECA, covering SOx, PM and NOx, also brings the role of continuous emissions monitoring increasingly to the fore. Therefore, a further consideration relating to the impact of this new ECA relates to vessel newbuilds and the stricter NOx Tier III requirements. For newbuilds subject to the stricter NOx Tier III requirements, compliance depends not only on engine certification at delivery, but on demonstrating that exhaust after-treatment systems, typically Selective Catalytic Reduction (SCR) or Exhaust Gas Recirculation (EGR), continue to perform as designed throughout the service life of the vessel.

For scrubber-equipped ships, real-time SO₂ measurement provides the operational evidence of equivalency that Port State Control inspections increasingly expect to see. Plus, for vessels operating under multiple overlapping regulatory regimes, including the new NE Atlantic ECA, EU MRV, EU ETS and FuelEU Maritime, continuous emissions monitoring via the VPS EMSYS CEM system delivers a single, verified source of emissions data that can be applied across all of them.

As noted by DNV in their MEPC 84 technical and regulatory update, the newly adopted IMO measurement guidelines can also be used for determining actual methane and nitrous oxide under the EU ETS and FuelEU Maritime, confirming the direct route from IMO-recognised measurement to EU compliance reporting.

At an operational level, the new ECA will introduce considerable complexity in the way fuel consumption is attributed across voyage segments, with VLSFOs burnt outside the zone and compliant fuels inside, all of which carry implications for consumption reporting, charterparty allocation and EU MRV alignment. VPS Maress can provide the underlying fuel and energy data into one auditable platform, helping crews manage the operational complexity that the new ECA introduces, including voyage segmentation, fuel changeover and emissions accounting, plus providing the consolidated data foundation that feeds existing EU MRV and IMO DCS reporting obligations. 

VPS PortStats via the VPS Verisphere eco-system, (VeriSphere | VPS), further supports bunker procurement planning with port-by-port intelligence on compliant fuel availability and price spreads. Such intelligence and insights, will prove particularly valuable in the months immediately following 1st September 2028, when the supply pressure on 0.10% sulphur fuels is likely to peak.

Regarding the more strategic decisions ahead, including Tier III engine selection for newbuilds, retrofit feasibility for existing tonnage, and charterparty clauses allocating the ECA fuel cost premium between owners and charterers, VPS Advisory Services can provide the integrated commercial and technical perspective needed to navigate this transition with confidence.

Therefore, its clear the impact of this new ECA, will not only affect the choice of fuel to be burnt onboard and its subsequent quality testing, but it will also require a review of, voyage planning, bunker procurement, scrubber strategy, engine certification, compliance documentation and charterparty exposure.

Related: DNV on IMO MEPC 84: Revisiting Net‑Zero Framework

 

Photo credit: VPS
Published: 14 May, 2026

Continue Reading

Scrubbers

No open-loop EGCS with HSFO bunker fuel allowed in Saudi Arabian ports

Use of HSFO with an Open-Loop Exhaust Gas Cleaning System at 0.5% or 0.1% sulphur mode setting is prohibited until further notice for the ships entering Saudi Arabian ports, says GAC.

Admin

Published

on

By

Aramco: Ras Tanura Port, Eastern Province of Saudi Arabia, on the Arabian Gulf.

The use of High Sulphur Fuel Oil (HSFO) with an Open-Loop Exhaust Gas Cleaning System (EGCS) at 0.5% or 0.1% sulphur mode setting is prohibited until further notice for the ships entering Saudi Arabian ports, according to GAC Hot Port News on Wednesday (3 December). 

All ships entering Aramco ports shall comply with one of the following options:

  • Use compliant fuel oil (≤ 0.50% m/m Sulphur, or ≤ 0.10% when operating in ECAs, if applicable).
  • Operate the EGCS in Closed-Loop mode (or Hybrid system in Closed mode), with strict prohibition on the discharge of wash water into the sea.

 

Photo credit: Aramco
Published: 8 December, 2025

Continue Reading

Bunker Fuel

Equatorial navigates through sanctions and green transition amid shifting bunkering landscape

Shipowners’ demand for ‘cheapest compliant fuel’ suggests a potentially more competitive and shrinking market for LSFO, forecasts Choong Sheen Mao, COO at Equatorial.

Admin

Published

on

By

Equatorial navigates through sanctions and green transition amid shifting bunkering landscape

Singapore-based physical bunker supplier Equatorial Marine Fuel Management Services Pte Ltd (Equatorial) is adapting to a dynamic global bunker market shaped by regulatory shifts, geopolitical tensions, and the push for decarbonisation, states its Chief Operating Officer.

Choong Sheen Mao was amongst panellists of the Bunker Sellers Panel at IBIA Annual Convention 2025 in Hong Kong on Tuesday (18 November) when he shared a significant trend of shipowners increasingly opting for high sulphur fuel oil (HSFO) paired with scrubbers, driven by the pursuit of the “cheapest compliant fuel”.

Despite a narrowing spread between high and low sulphur fuels – from approximately USD 125 to USD 80, and occasionally below USD 70 – shipowners continue to see long-term investment returns from scrubbers. This shift suggests a potentially more competitive and shrinking market for low sulphur fuel oil (LSFO).

“Geopolitical instabilities, particularly armed conflicts, sanctions and trade wars, are creating considerable market distortions. These instabilities lead to supply disruptions, cargo rerouting, and impact bunker prices,” added Choong.

“Compliance has become a paramount concern, with recent substantial fines underscoring the risks involved. The current economic slowdown, compounded by sanctions and self-sanctioning, presents a ‘double pain’ for the market.

“The market’s daily volatility is also heavily influenced by global politics, making it challenging to assess without a deep understanding of geopolitical events.”

To ensure marine fuel quality, Equatorial emphasises managing its own supply chain and operating its own fleet of bunkering vessels, allowing for direct control from delivery to the customer, he stated.

This approach prioritises transparency and security, fostering long-term relationships where quality issues can be collaboratively addressed. Knowledge sharing, especially concerning parameters from new bunker fuel testing methods such as Gas Chromatography Mass Spectrometry (GC-MS), is also deemed crucial.

Supporting the transition to alternative marine fuels, while acknowledging the uncertainty surrounding the dominant future fuel, Equatorial has strategically invested in IMO Type 2 chemical tankers capable of handling methanol, biofuel, and conventional bunker fuels.

“Biofuel is identified as the most effective short-term solution, offering favourable pricing and operational costs compared to other green alternatives,” explained Choong.

“However, challenges include feedstock availability and potential export quotas from key producing nations like China.

“The adoption of alternative marine fuels necessitates a closer, more collaborative relationship between buyers and sellers.

“This involves detailed discussions on specific fuel specifications beyond standard ISO requirements, extensive lab sampling, and long-term commitments from both parties, particularly given the absence of a liquid hedging market for biofuels.

“Collaboration across safety, quality, and commercial aspects is essential for the successful implementation of bio bunker fuels to the future maritime market.”

 

Photo credit: International Bunker Industry Association
Published: 1 December, 2025

Continue Reading

Trending