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PROJECT FORWARD is a Joint Development Project to combat global ship emissions by promoting the adoption of liquefied natural gas as a marine fuel. Conceived in 2013, and funded by Arista Shipping, Project Forward was presented in 2015. Forward identified the potential of liquefied natural gas (LNG) as a marine fuel, and engaged in an extensive R&D program which arrived at a technically reliable and commercially feasible design of our Kamsarmax size bulk carrier which apart from its extremely low environmental footprint, reduces the cost of transportation at sea, modernizes the shipping industry and defines the new standard of vessel for immediate employment post-IMO's 2020 emission rules.  

Forward's commercially attractive LNG-powered deep sea dry bulk carrier complies with and exceeds all known, applicable, and forthcoming environmental regulations, including International Maritime Organization’s (IMO) Energy Efficiency Design Index 2025 standardsNOx Tier III and Marpol Annex VI SOx emission levels. The main aspects of the patented design are the use of membrane-type tank for the LNG containment designed by GTT, and the use of only two 4-stroke medium speed Wärtsilä 31DF engines featuring twin stage turbocharging with power take-off / take-out and take-in (PTO / PTI), and controllable pitch propeller (CPP), without the need for the customary three auxiliary generator engines, all of which when combined offer superior redundancy, less maintenance cost, enhanced safety, and improved maneuverability. The design is scalable and Forward’s solutions, proprietary concepts and designs including the machinery arrangement, and pending patents, are equally applicable to tankers and container ships.

Since 2013, Arista has been joined in its R&D efforts by a prestigious and powerful group of industry leaders consisting of ABS (American Bureau of Shipping, one of the world’s leading ship classification societies), Deltamarin (a ship design, offshore engineering and construction group operating in the marine and offshore industries worldwide), GTT (Gaztransport & Technigaz, the leading engineering company specialized in the design of membrane containment systems for the maritime transportation and storage of liquefied gas), Wärtsilä (a corporation which manufactures and services state of the art power sources and other equipment in the marine and energy markets) and Shell (Royal Dutch Shell plc) has also linked with Project Forward to assist in the global distribution of LNG.

Project Forward


The Heavy Fuel Oil (HFO) used by marine vessels today with a maximum sulphur content of 3.5% will not meet the global sulphur cap of 0.5% coming into force from 2020. Further refining of the HFO and blending with gasoil is required to meet the maximum sulphur content of 0.5%, which also increases the price of the fuel. Low sulphur HFO is still not widely available, but the low sulphur fuels used today are Marine Diesel Oil (MDO) with a maximum sulphur content of 1%, and Marine Gas Fuel (MGO) with a maximum sulphur content of 0.1%.

The price for fuel with a maximum sulphur content of 0.5% is still open. The MDO used today can be further refined, and also the possible increased use of gasoil will enable the sulphur cap of 0.5% to be met. Therefore, the price of MDO today might be the best indicator for foreseeing the complying diesel oil price in 2020. Some oil majors are already developing low sulphur HFO, and have indicated that the price for low sulphur HFO would be somewhere between the current HFO and MDO prices. Naturally nobody yet knows for sure what the price of low sulphur fuel will be in the future, but many ship owners anticipate that it will be close to the price of MDO.
The only alternative for meeting the maximum sulphur content of 0.5% with the HFO currently available is to clean the engine exhaust gases of sulphur oxides using an SOx scrubber. Many ship owners have already opted for SOx scrubbers in their newbuildings, because the additional price for low sulphur fuel oils has, at least historically, been considerably higher than for conventional HFO. The anticipation is that the additional investment for the SOx scrubber will pay itself back within a reasonable time frame since it allows the ship to operate on conventional HFO. Figure 2 indicates the historical fuel prices on the USA’s West Coast (IFO380 is generally considered to be the most commonly used HFO).

Today, there is already a sulphur cap of 0.1% within Emission Control Areas, so the industry has to some extent learned how to operate on low sulphur fuels. However, the large-scale global sulphur cap of 0.5% must anyway be considered as a major challenge for the shipping industry. Large ocean-going vessels have thus far only had to use low-sulphur fuel periodically when sailing within Emission Control Areas. At other times they have operated normally on conventional HFO. Having to permanently comply with the low sulphur legislation will lead to changes in the marine sector far more reaching than we have seen earlier.


In addition to the global sulphur cap of 0.5%, additional emissions legislation is also entering into force. New ships will have to comply with IMO Tier III regulations when operating within Emission Control Areas. IMO Tier III means that the NOx emissions will have to be 80% lower than those specified by the IMO Tier I levels introduced in the year 2000. New ships with keel laying after 1.1.2016 for North American waters, and keel laying after 1.1.2021 for the Northern European Emission Control Areas will have to comply with the IMO Tier III legislation. Diesel engines can only meet IMO Tier III with catalysts, i.e. Selective Catalytic Reduction units (SCR). An alternative means of meeting the IMO Tier III levels might also be to use Exhaust Gas Recirculation (EGR), although this technology has still to be further validated.



Emissions legislation will increase the operational costs of shipping. If no after treatment units are installed, low sulfur diesel oil will have to be used, which is more expensive than conventional HFO. If after treatment units are installed, the cost of the ship will increase, while operating the after-treatment units will also increase operating costs. The after-treatment equipment creates an increased electrical power demand because of the additional pumps required. Additional costs for the removal of the sludge when in port will also need to be considered. Furthermore, operating with SCRs will require the use of urea, which will have to be separately bunkered. All after-treatment equipment also requires maintenance, meaning that the overall maintenance costs will also increase.


Emission Control Area expansions

Global maximum sulphur cap of 0.5%
NOx emissions - IMO Tier III within Emission Control Areas
Increasing costs because of emissions legislation


Because of the anticipated cost increases for operating on diesel oil, there is growing interest in alternative fuels. Electric powered vessels, meaning battery or hybrid propulsion, will play an important role in future shipping operations, but the battery technology available today still only allows for very short distances when running purely on electricity. For example, ferries with transit times of, say, half an hour are a good fit for purely battery powered vessels.
The alternative fuel that looks most promising today is LNG. Natural gas production worldwide is increasing, and together with renewables, gas is taking an increasing share of the global energy market. Natural gas traded as LNG is growing by some 6 to 8% per year. Of all the fossil fuels natural gas is the cleanest, and because of emissions legislation is increasing being used for fueling ships.

Operating on LNG delivers lower emission levels than when operating on diesel oil, as illustrated in figure 4 below. Gas or dual-fuel engines running on gas according to the Otto cycle, have a 25% lower level of CO2 emissions, while NOx emissions are 85% lower than for a diesel engine. This enables compliance with the IMO Tier III levels without the need of an SCR. As LNG does not include any sulfur, it also fulfills all sulfur regulations


Comparison of emission levels, gas engine vs. diesel engine

Alternative fuels – LNG

Fig.3 Below, a high-pressure SCR unit for a Win GD 6X72 engine undergoing shop testing at Hyundai Heavy Industries. Underneath, an illustration of an SOx scrubber installation on a main engine


It is not easy to guess which marine fuel will be predominant in the future. The most challenging part probably is to foresee future fuel prices; how will low sulfur fuel be priced, and how will the price spread be compared to conventional HFO and LNG? There are still many open items that will need to be settled. Until this has happened we can only try to estimate what the most logical outcome could be.

Taking into consideration the higher production costs and increased use of gasoil to produce low sulfur fuel with a maximum sulfur content of 0.5%, it is likely that the price for low sulfur fuel will be high. One reference point for the price of 0.5% sulfur fuel is the price of MDO. Comparing the historical price spread between HFO and MDO presented in figure 2 on the left further strengthens the case for anticipating that the price of low sulfur fuel will be high. The IMO has published an extensive report, its “Assessment of fuel oil availability”, in July 2016 (IMO MEPC 70/INF.6). In the IMO report the price of different fuels is evaluated and are shown in figure 6.

The choice between low sulphur fuel, SOx scrubbers or LNG for newbuildings
Fuel Savings


Projected Fuel Oil prices in 2020, source IMO MEPC 70/INF.6



The price spread shown in figure 6 between 0.5% sulfur fuel and 3% sulfur fuel is 130 USD/ton, which compared to the 10 year historical prices between HFO and MDO it is a moderate price spread. However, even with this modest price spread of 130 USD/ton, the pay-back time for SOx scrubbers will be very short compared to running on 0.5% sulfur fuel. In addition, by the end of 2019 the demand for 0.5% sulfur fuel is expected to grow from zero to approximately 75% of the global marine fuel demand. It remains to be seen how this tremendous growth in demand will work in practice, i.e. how supply will meet demand, see figure 7 below. Based on this assessment, alternatives such as SOx scrubbers or LNG should be more economically viable for newbuildings

The Perfect Price Arbitrage


Illustration of the transition to 0.5% Low Sulphur Fuel (Shell)

Fig 2.

Historical Fuel Prices on the US West Coast, HFO, MDO and LNG

"The implementation by the IMO of new tighter global bunker specifications is just around the corner in 2020 and will be one of the most disruptive changes to ever affect the refining and shipping industries. It will have a global impact in excess of $1 trillion over 5 years."
APRIL 11, 2018
MARCH 2017


LNG fuel is available in 150 global locations and overlapping with key maritime hubs 

HiLo Spread - Bloomberg 20190812



Shell will supply LNG to FORWARD and at a percentage discount over LFO on an energy content basis, ensuring  operational competitiveness.


The bottleneck holding back greater LNG use has been the bunkering availability of LNG. Neither has the price of LNG always been competitive compared to conventional HFO. Today there are a little more than 100 LNG fueled vessels in operation, and by 2019 this number will have increased to more than 200. The LNG bunkering infrastructure is, therefore, gradually improving as shown in figure 5. As more and more ship owners are opting for LNG as fuel for their newbuildings, LNG bunkering volumes are increasing. However, most of the LNG fueled vessels are operating in northern Europe, but ports worldwide are also showing an increased interest in offering LNG.

Shell has committed to bunkering capacity for Forward Bulkers to sufficiently launch its operation in 2020.

LNG Bunkering Availability
LNG is generally avalable for bunkering
Game-changing Environment



For newbuildings today, emissions legislation is a game-changer. It can be foreseen that the price of low sulfur fuels will be high, and for this reason machinery alternatives with either after-treatment systems or LNG fueled machinery must be seriously considered. The emissions legislation will in any case increase shipping costs, but the machinery choice for newbuildings is currently probably more challenging than ever before.

This report presents the International Code of Safety for Ships using Gases or other Low-flashpoint Fuels (IGF Code). This Code sets the requirements for safe design, construction, and operation, of LNG-fueled vessels. On the EU frame the Sulfur Directive and the Directive on the deployment of an Alternative Fuels Infrastructure establish the European framework for the development of LNG as an alternative fuel for shipping.
Enforcement & Compliance
In a historical decision on February 9, 2018, IMO DECIDED TO OUTLAW THE CARRIAGE OF HIGH SULFUR FUEL AHEAD OF 2020.
"I am very pleased to see this unprecedented and very strong signal from all sides, industry and NGOs, to support a global ban on high sulfur fuels."
Søren Toft,
CEO of Maersk Line
"We discounted using scrubbers for IMO 2020 compliance, with the switch to compliant fuel the only way to ensure a swift and effective compliance for the 2020 Global Sulfur Cap."
Niels Henrik Lindegaard,
Head of Maersk Oil Trading



According to the US EPA, ocean going vessels emit significant pollution that not only effect populations living near ports and coastlines, but also those living hundreds of miles inland. Marine diesel engines generate significant emissions of NOx, fine particulate matter (PM2.5), and sulfur oxides (SOx) that contribute to non-attainment of the National Ambient Air Quality Standards for PM2.5 and ozone.

These engines also emit hydrocarbons (HC), carbon monoxide (CO), and hazardous air pollutants or air toxics that are associated with adverse health effects. Emissions from these engines also cause harm to public welfare, and contribute to visibility impairment and other detrimental environmental impacts across the United States.

Large marine diesel engines are significant contributors to our national mobile source emission inventory and their contribution is expected to grow in the future. At the current rate, NOx emissions from ships are projected to more than double to 2.1 million tons a year while annual PM2.5 emissions are expected to almost triple to 170,000 tons a year by 2030.

On February 9, 2018, IMO agreed to move forward with a prohibition on the carriage of fuel oil for use on board ships, when that fuel oil is not compliant with a new low sulfur limit which comes into force from 2020.  The aim of the new limit is to reduce sulfur oxide (SOx) emissions from ships to improve air quality and protect the environment.

To help ensure consistent implementation of this regulation, IMO’s Sub-Committee on Pollution Prevention and Response (PPR), which met (5-9 February) at IMO headquarters, London, agreed draft amendments to the MARPOL Convention on the prevention of pollution from ships (MARPOL Annex VI) to prohibit the carriage of non-compliant fuel oil, such that the sulfur content of any fuel oil used or carried for use on board ships shall not exceed 0.50%.

The exception would be for ships fitted with an approved “equivalent arrangement” to meet the sulfur limit – such as an exhaust gas cleaning system (EGCS) or so-called “scrubber” – which are already permitted under regulation 4.1 of MARPOL Annex VI. These arrangements can be used with “heavy” high sulfur fuel oil as EGCS clean the emissions and therefore can be accepted as being at least as effective at meeting the required sulfur limit. For a ship without an approved equivalent arrangement the sulfur content of any fuel oil carried for use on board shall not exceed 0.50%. 

This is yet another triumph for environmental organisations which joined together with shipping organisations in calling for a ban on transporting fuel oil that does not meet the new 0.5% sulfur cap which comes into to force in just under two years' time.


The organisations say that this ban will aid the enforcement of the global sulfur cap.


"To secure the intended environmental and health benefits, the organisations say it is of utmost importance that enforcement of this standard is efficient and robust globally," said a statement issued by environmental outfit Transport & Environment. It went on: "Any failure by governments to ensure consistent implementation and enforcement could also lead to serious market distortion and unfair competition.

"In a joint statement ahead of the above-mentioned IMO meeting of Fabruary 9, 2018, environmental and shipping organisations asserted that such a ban will help ensure robust, simplified and consistent enforcement of the global sulphur cap."

Organisations in support of this ban have been BIMCO, Clean Shipping Coalition, Cruise Lines International Association, Friends of the Earth US, International Chamber of Shipping, International Parcel Tankers' Association, INTERTANKO, Pacific Environment, World Shipping Council, and WWF Global Arctic Programme. 

Further, in a vocal message, Maersk Line was also backing this "unprecedented" call for a ban on the carriage of high sulfur bunker fuels, arguing it is the best way to enforce the upcoming IMO 2020 regulations.


Sentinel tracks ships' dirty emissions from orbit (April 2018)

The new EU satellite tasked with tracking dirty air has demonstrated how it will become a powerful tool to monitor emissions from shipping.

Sentinel-5P was launched in October last year and this week completed its in-orbit commissioning phase. But already it is clear the satellite's data will be transformative.

The latest image on the left reveals the trail of nitrogen dioxide left in the air as ships move in and out of the Mediterranean Sea.  The "highway" that the vessels use to navigate the Strait of Gibraltar is easily discerned by S5P's Tropomi instrument.

Sentinel-5P is the next big step because of its greater sensitivity and sharper view of the atmosphere. "Shipping lanes are something we've seen on previous missions but only after we've averaged a lot of data; so, over a month or a year. But with Tropomi we see these shipping lanes with a single image," Dr Veefkind told BBC News.

"The resolution we got from our previous instruments was about 20km by 20km. Now, we've gone down to 7km by 3.5km, and we are thinking of going to even smaller pixels."

Europe's Sentinel programme is part of the answer. Suddenly, at just the right time, the world's shipping lanes are in full view.

S5P's availability is timely. The shipping sector has just signalled its intention to make big reductions in its emissions over the next 30 years, in particular of the greenhouse gas carbon dioxide. At the moment, those emissions are calculated in a "bottom-up" fashion. By knowing the size of the global fleet, where it moves, the ships' specifications and how much fuel they are likely consuming - it is possible to estimate how much CO₂, or indeed NO₂, is being pumped into the atmosphere from exhausts.

But this all involves quite a few assumptions, and so the models need to be audited by some top-down analysis as well - which is where satellites come in.

S5P-Tropomi does not see CO₂, although its NO₂ observations can act as a tracer in the sense that wherever nitrogen dioxide turns up on shipping lanes, there will be CO₂ present, too.

But the best solution would be a dedicated carbon-monitoring satellite. This is why the EU has asked its technical agent on space matters, the European Space Agency, to design a Sentinel specific to the task. Dubbed Sentinel 7 by many people, because that is the next available number in the series, this future mission should fly in the 2020s.

The aim is to be able track CO₂ down through the atmosphere on a scale of around 3km by 3km, but over a wide area. That would make Sentinel 7 a forceful partner for Sentinel 5.




If a vessel violates intentionally a specified national or international law by default the insurance coverage of a vessel becomes reserved . No Charterer, cargo owner or trader will be willing to trade with an uninsured vessel. It is not only their own willingness to trade, or not, with such a vessel but also the inherent complications with their letters of credit and associates. Port Authorities will also prevent the sailing of uninsured vessels from ports of their jurisdiction.

IMO Moves Forward with Ban on Vessels Carrying High-Sulphur Fuel

April 13, 2018


The International Maritime Organization said it approved an amendment that bans ships unequipped to strip sulfur from carrying high-sulfur fuel from 2020 – when new sulfur-content limits come into effect.

New 2020 limits cut the amount of sulfur in the fuel that ships worldwide are allowed to use, from 3.5 to 0.5 percent by 2020. However, ships that have installed scrubbers that can remove sulfur as fuel is burned can continue to use higher-sulfur fuel.

The amendment to MARPOL Annex VI approved on April 13 makes it illegal for ships without scrubbers to carry fuels above the sulfur limit in their supply systems, but would allow any ship to carry higher sulfur fuels as cargo
The approval is the second to last step required in order to formalize the ban on carrying fuel oil – which is itself a step aimed at making it easier to enforce the stricter sulfur limits. The IMO will next have to formally adopt the amendment at the group’s meeting in October 



The IMO has launched a document answering frequently asked questions about the upcoming sulfur emissions regulations taking effect in 2020.

IMO regulations to SOx emissions from ships first came into force in 2005, under Annex VI of the MARPOL Convention. Since then, the limits on sulfur oxides have been progressively tightened. From January 1, 2020, the limit for sulfur in fuel oil used on board ships operating outside designated emission control areas will be reduced to 0.50 percent m/m (mass by mass). This will significantly reduce the amount of sulfur oxides emanating from ships and should have major health and environmental benefits for the world, particularly for populations living close to ports and coasts, says the IMO.

Answers to some frequently asked questions are:
Limiting SOx emissions from ships will have a very positive impact on human health: how does that work?

Simply put, limiting sulfur oxides emissions from ships reduces air pollution and results in a cleaner environment. Reducing SOx also reduces particulate matter, tiny harmful particles which form when fuel is burnt. 

A study on the human health impacts of SOx emissions from ships, submitted to IMO’s Marine Environment Protection Committee (MEPC) in 2016 by Finland, estimated that by not reducing the SOx limit for ships from 2020, the air pollution from ships would contribute to more than 570,000 additional premature deaths worldwide between 2020-2025.   

So a reduction in the limit for sulfur in fuel oil used on board ships will have tangible health benefits, particularly for populations living close to ports and major shipping routes.

Why are ships already less harmful than other forms of transport?

Ships do emit pollutants and other harmful emissions. But they also transport large quantities of vital goods across the world’s oceans – and seaborne trade continues to increase. In 2016, ships carried more than 10 billion tons of trade for the first time, according to UNCTAD. 

So ships have always been the most sustainable way to transport commodities and goods. And ships increasingly becoming even more energy efficient. IMO regulations on energy efficiency support the demand for ever greener and cleaner shipping. A ship which is more energy efficient burns less fuel so emits less air pollution.

It has sometimes been quoted that just a few ships (all using fuel oil with maximum permitted sulfur content) emit as much harmful air pollutants as all the cars in the world (if the cars were all using the cleanest fuel available).

Not only is this the very worst case scenario, but this does not take into account the amount of cargo that is being carried by those ships and the relative efficiency. It is important to consider the amount of cargo carried and the emissions per tonne of cargo carried, per kilometer traveled. Studies have shown that ships are by far the most energy-efficient form of transportation, compared with other modes such as aviation, road trucks and even railways.

It is also relevant to remember that shipping responds to the demands of world trade. As world trade increases, more ship capacity will be needed.  

How can ships carry so much cargo so efficiently?

Ships are the largest machines on the planet and the world’s largest diesel engines can be found on cargo ships. These engines can be as tall as a four-storey house, and as wide as three London buses. The largest marine diesel engines have more than 100,000 horsepower (in comparison, a mid-sized car may have up to 300 horsepower). But the largest container ships can carry more than 20,000 containers and the biggest bulk carriers can carry more than 300,000 tons of commodities, like iron ore.

So powerful engines are needed to propel a ship through the sea. And it is important to consider how much energy is used to carry each ton of cargo per kilometer. When you look at the relative energy efficiency of different modes of transport, ships are by far the most energy efficient. 

Ships can reduce air pollutants by being even more energy efficient, so they burn less fuel and therefore their emissions are lower.    

What is the current regulation on SOx in ships emissions, and by how much is that going to be improved?

We are going to see a substantial cut: to 0.50 percent m/m (mass by mass) from 3.50 percent m/m.

For ships operating outside designated emission control areas the current limit for sulfur content of ships’ fuel oil is 3.50 percent m/m.

The new limit will be 0.50 percent m/m which will apply on and after January 1, 2020.

There is an even stricter limit of 0.10 percent m/m already in effect in emission control areas (ECAS) which have been established by IMO. This 0.10 percent m/m limit applies in the four established ECAS: the Baltic Sea area; the North Sea area; the North American area (covering designated coastal areas off the U.S. and Canada); and the U.S. Caribbean Sea area (around Puerto Rico and the United States Virgin Islands).

Fuel oil providers already supply fuel oil which meets the 0.10 percent m/m limit (such as marine distillate and ultra low sulfur fuel oil blends) to ships which require this fuel to trade in the ECAs.

What must ships do to meet the new IMO regulations?

The IMO MARPOL regulations limit the sulfur content in fuel oil. So ships need to use fuel oil which is inherently low enough in sulfur, in order to meet IMO requirements.

Some ships limit the air pollutants by installing exhaust gas cleaning systems, also known as “scrubbers”. This is accepted by flag States as an alternative means to meet the sulfur limit requirement.

Ships can have engines which can use different fuels, which may contain low or zero sulfur. For example, liquefied natural gas or biofuels.    

Could the 0.50 percent limit be delayed?

No. There can be no change in the January 1, 2020 implementation date, as it is too late now to amend the date and for any revised date to enter into force before January 1, 2020.
Will new fuels be needed to meet the 2020 limit? Will there be enough?

It is likely that new blends of fuel oil for ships will be developed, For example, a gas oil, with a very low sulfur content can be blended with heavy fuel oil to lower its sulfur content.

These new blends are likely to cost more initially than the heavy fuel oil bunker fuel used by the majority of ships today. Ships can also choose to switch to a different fuel altogether. Or they may continue to purchase heavy fuel oil, but install scrubbers to reduce the output of SOx in order to have an equivalent means to meet the requirement.

Of course, some ships are already using low sulfur fuel oil to meet the even more stringent limits of 0.10 percent m/m when trading in the already-established emission control areas. So those fuel oil blends suitable for ECAS, will also meet the 0.50 percent m/m limit in 2020. However, there is a cost differential, and these blends are more expensive than heavy fuel oil.

A study commissioned by IMO into the "Assessment of fuel oil availability" concluded that the refinery sector has the capability to supply sufficient quantities of marine fuels with a sulfur content of 0.50% m/m or less and with a sulfur content of 0.10 percent m/m or less to meet demand for these products, while also meeting demand for non-marine fuels. 

Consistent compliance with the new limit is vital. What is IMO doing about that?

Monitoring, compliance and enforcement of the new limit falls to Governments and national authorities of Member States that are Parties to MARPOL Annex VI. Flag States and port States have rights and responsibilities to enforce compliance. 

IMO is working with Member States as well as industry (including the shipping industry and the bunker supply and refining industry) to identify and mitigate transitional issues so that ships may meet the new requirement.

For example, developing guidance, developing standardized formats for reporting fuel oil non availability if a ship cannot obtain compliant fuel oil and considering verification and control issues.


June 8, 2018

ABS issued the ABS Advisory on Marine Fuel Oil to help industry prepare for the IMO’s 2020 global sulfur cap. The Advisory provides owners and operators with industry-leading guidance on the considerations and challenges with marine fuels, which are likely to be used in addressing the 2020 global sulfur cap requirements.

“The IMO 2020 sulfur cap requirement will introduce a significant demand change from heavy fuel to low sulfur fuel almost overnight. The industry currently is debating how to prepare as the consequences of this shift are difficult to predict,“ said Dr. Kirsi Tikka, ABS Executive Vice President and Senior Maritime Advisor. “The ABS Advisory addresses concerns about the safety impacts and quality of the new blended and hybrid fuels that are currently not covered by the ISO fuel standard, and provides guidance on fuel selection, modification considerations and operational challenges.”

In a recent informal poll of shipowners and operators conducted by ABS, 53 percent said their fleets were not yet ready to meet upcoming sulfur cap requirements. As the deadline for compliance approaches, it is vital that industry consider the available options and the impacts on their fleets. The ABS Advisory provides in-depth technical guidance covering a range of topics, from fuel properties to operational risks to potential preparations. Using this Advisory to understand the implications of different marine fuels, owners and operators can make smarter decisions on the future of their fleets.

The available options to comply with the global sulfur cap include exhaust gas cleaning, burning compliant fuel or alternative fuels. In 2010, ABS provided guidance on switching from heavy fuel to 0.1% sulfur fuel when entering Emission Control Areas. This Advisory has been widely used by the industry, and ABS has now updated this guidance to cover the regulation entering into force in January 2020.
The updated ABS Advisory includes background on air emission regulations and evaluates several relevant fuel types and the associated impacts and operational challenges for each.



•    The methane slip is a side effect of low pressure concept, but engine technology (combustion chamber design, control of valve timing and fuel injection) can reduce it drastically.

•    Our engines offer a net reduction of CO2 emissions inclusive of methane slip which at design load can reach 25%.


•    NOx is a product of the internal combustion process itself, created from the air in the cylinder chamber by the temperatures and pressures of combustion. Engines emit NOx to varying degrees no matter what fuel is used. That is why many ships using natural gas as fuel also have catalytic NOx removal systems treating their exhaust gases. FORWARD wanted to control the engine’s NOx production so as to eliminate the need for exhaust treatment, but to do so they had to conquer the problem of ‘methane slip’ – the tendency of gas-fueled diesels to allow a small amount methane to leave the cylinder unburned, or ‘slip out’ into the exhaust. If you want to cut greenhouse gas emissions, you certainly don’t want methane slip. 


•    One traditional technical challenge to using gas a marine fuel has been an unavoidable trade-off between NOx production and methane slip, a problem that stems from a combination of thermodynamics and engine technology. Engines operate according to one of two thermodynamic cycles, Otto or Diesel. The Otto cycle – which is employed in automobile engines – is the lower-pressure of the two, and by nature generate very low NOx levels; the drawback to Otto engines when fueled by natural gas is that the generate methane slip. Diesel cycle engines, operating at higher temperatures and pressures, burn the entire charge of methane in the cylinder but generate far more NOx. The answer to this persistent problem was drawn from the engine itself.


•    We found the latest DF engine, which is much advanced over previous versions, gave us the possibility to adjust the methane slip. Through careful use of the technology in this new low-pressure system we were able to reduce the slip to very, very low levels, and achieve both objectives at once. And, once we identified the low-pressure system as the one closest to what we need, we developed the concept of two engines doing everything.

For more information and the latest on this debatable subject, please check the study prepared  for SEA\LNG and SGMF by the company ThinkStep. You can download it here by registering your details or for the executive summary, please click on the report picture herein.  This study showed that on an engine technology basis, the absolute Well-to-Wake emissions reduction benefits for gas-fueled engines today compared with HFO fuelled ships are between 14% to 21% for 2-stroke slow speed engines, and between 7% to 15% for 4-stroke medium speed engines.  Data for the study was provided by the following Original Equipment Manufacturers: Catapillar, MaK, Caterpillar Solar Turbines, GE, MAN Energy Solutions, Rolls Royce (MTU), Winterthur Gas & Diesel, Wärtsilä.  The extensive industry experience and practical knowledge of the SEA\LNG-SGMF project oversight team ensured all the data used was the latest and best available. Forward Ships is a member of SGMF.

On Methane Slip
Towards 2050
IMO agrees to a target of 50% reduction of CO2 emissions in 2050.


April 13, 2018

After a week of negotiations at a London meeting of the International Maritime Organization, envoys from 173 countries agreed to cut emissions by at least 50 percent by 2050 from 2008 levels. Saudi Arabia, the U.S. and Russia all objected.

The accord is a significant step in the fight against global warming. Shipping, the only industry not included in the 2015 Paris climate agreement, would rank as the sixth-largest greenhouse gas emitter if it were a country, according to the World Bank. If left unchecked, that share could account for 15 percent of global carbon emissions by 2050, a five-fold increase from today.

“It is likely this target will tighten further, but even with the lowest level of ambition, the shipping industry will require rapid technological changes,” said Tristan Smith, a reader at University College London’s Energy Institute.

Vessels typically burn heavy fuel oil, one of the cheapest but also among the dirtiest fossil fuels. The industry wasn’t included in the Paris agreement because each country presented an individual plan to reduce their own emissions, while the seas were left out.

April 13´s agreement commits to pursuing emission cuts that will be consistent with the Paris deal goals.



Shipping's goal to cut its carbon dioxide (CO2) emissions in half by 2050 would not be reached even if the industry switched over completely to liquefied natural gas (LNG).
Having run the numbers, analyst JBC found that a switch to LNG-fueled shipping "will not by itself be enough".


Even if the entire global shipping fleet were to switch to LNG -- which has a CO2 emission factor about 27-30% lower than the conventional bunker fuel -- the industry would still be short of its CO2 reduction targets by 350 million metric tonnes, Reuters reports.

The industry will have to find additional ways to cut CO2 emissions, including efficiency gains, carbon capture and storage, hybrids and batteries, the analyst said.

Forward Ships commits to leading the way to the decarbonization of shipping as we approach 2050. With its advanced, future-proof design, Forward Ships proves it has the solution for 2050 and beyond. 

We will be our strongest competitor.


Forward Ships proves that the 2050 - 70 percent reduction in carbon intensity (tons per ton-mile) target can be met, even without lowering service speeds, through the use of LNG mixed with carbon neutral fuels (e.g. biomethane):

Photo from Forward Ships model tests at HSVA, Hamburg
September 2018
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