Advanced BioFuels USA

Setting the Course to Low Carbon Shipping examines new fuels, technologies and operational measures and matches that with forecasts for the world’s key trade lanes to envision what shipping may look like in 2030 and 2050.

The second of two ‘Outlook’ documents – the first was published in June 2019 – it applies what ABS currently knows about existing and future fuels to project which energy source could be best suited for each trade lane and what that may mean for the design of the vessels working them.

“Maritime’s decarbonization challenge can be regarded as a complex riddle with three elements: vessel energy efficient technologies, operational optimization and low and zero carbon or carbon neutral fuels. All elements have a role to play, but we have identified that the rate of shipping’s transition to lower carbon fuels will have the single biggest impact on its global carbon footprint; more than any predictable shifts in commodity demand, enhancements to operating practices, vessel routings, or ship designs.,” said Christopher J. Wiernicki, ABS Chairman, President and Chief Executive Officer. “The models in our research suggest our industry will meet the targets for the reduction in carbon intensity by 2050, but it might miss the target for the total GHG emitted annually. In short, there is a gap between the industry’s present course, and its stated ambition.”

Palle B. Laursen, Maersk Chief Technical Officer, said: “In Maersk, we have for more than a decade been industry leaders in CO2 efficiency, and we have set ourselves the bold target of becoming carbon neutral by 2050. To bring this ambition to life, we need to bring the first commercially viable carbon neutral vessel into operation by 2030 already, which can only happen if we work together across the industry and supply chain, which is why the research from ABS on decarbonization pathways and what shipping may look like in the future is well timed. The study is thorough and comprehensive, and links the task ahead with practical steps of implementation.”

ABS collaborated with Maritime Strategies International (MSI) to create a global scenario for the future CO2 emissions from shipping, which takes into account the future variation of fuels used in vessels, as well as the decarbonization of different industrial sectors on which shipping depends. ABS also worked with Herbert Engineering Corp. (HEC) to develop a series of tanker, bulk carrier and container ship design concepts to explore practical options for meeting IMO greenhouse gas goals.

Research in the Outlook suggests that, on the current trajectory, petroleum-based fuels will still have considerable market share by 2050, which has significant implications for meeting the emissions challenge.
…
Download a copy of Setting the Course to Low Carbon Shipping here.

ABS, a leading global provider of classification and technical advisory services to the marine and offshore industries, is committed to setting standards for safety and excellence in design and construction. Focused on safe and practical application of advanced technologies and digital solutions, ABS works with industry and clients to develop accurate and cost-effective compliance, optimized performance and operational efficiency for marine and offshore assets.  READ MORE

Excerpt from Setting the Course to Low Carbon Shipping:  While reducing carbon dioxide (CO2 ) and other greenhouse gases (GHG) is a separate challenge from current efforts to lower shipping’s output of pollutants such as nitrogen oxides (NOx ) and sulfur oxides (SOx), both put the health of the environment and the livelihood of those who depend on them at risk. For shipping, a “zero-carbon future” is an aspirational goal, and the associated regulatory pathways will evolve alongside the changes it inspires in ship design, technology and practices.

Importantly, progress must be achieved strategically and holistically if the maritime industry is to emerge more efficient, profitable and sustainable than it is today.

In recognition of this goal, ABS has developed the second in a series of “Outlook” documents — the first was published in June 2019 — to reference available carbon-reduction strategies and inform the shipping industry as it enters the uncharted waters of the 2030/2050 emissions challenge.

This document examines how the development of global trade will impact global emissions. Furthermore, it identifies the three main fuel pathways on the course to meeting the IMO’s emission reduction targets for 2050 and beyond: light gas fuels, heavy gas fuels and bio/synthetic fuels. It also examines the possible capacity demand and related emissions output trends on a global basis to envision the environments in which those targets may need to be achieved.

…

THE LIGHT GAS PATHWAY

This category includes fuels comprised of small molecules with low-carbon/hydrogen (C/H) ratio, which helps
to reduce carbon emissions, and in the case of methane (CH4 ) high energy content. However, they require
cryogenic storage and more demanding fuel delivery systems.

Such fuels include LNG, bio-LNG, and synthetic natural gas (SNG) or renewable natural gas (RNG), which can be
produced from biomass and/or by using renewable energy. The production of the synthetic or renewable fuels
from biomass is currently limited in scale and will have to be increased before they can be considered as viable
commercial solutions.

LNG is a relatively mature low-carbon fuel, comprised primarily of methane. Its C/H ratio offers a reduction in
carbon dioxide (CO2) emissions of up to 21 percent compared to baseline heavy fuel oils4. This value does not
include carbon release from methane slip, which may be an issue in two-stroke or four-stroke engines that
operate on LNG in the Otto cycle.

Minimizing methane slip is critical to the commercial adoption of these renewable fuels. The industry is
currently developing in-cylinder emissions control strategies, which could be combined with aftertreatment
systems. By minimizing methane slip, fuels such as bio-LNG and SNG/RNG can offer carbon-neutral propulsion.

The two-stroke and four-stroke engine manufacturers already offer solutions for minimizing methane slip from combustion, using high-pressure gas injection in the cylinder. These can be combined with methane oxidation catalysts and other aftertreatment systems used to treat the exhaust gas to further reduce the methane emissions and minimize the carbon output of using LNG.

As a low-carbon fuel, LNG can be combined with new technologies and/or operational measures to meet the 2030 emissions-reduction goals, and it can contribute to further reductions in future, if blended with bioLNG or SNG/RNG.

If the latter can be commercialized and made available at large scale in the medium term, the carbon footprint from using LNG would be reduced in proportion to the amount of renewable fuel used in the blend.

Given the carbon neutral promise of bio-LNG and SNG/RNG, significant efforts are currently being made to explore these solutions for commercial use.

At the end of the light gas spectrum, hydrogen may be a solution for future zero-carbon marine vessels. It offers the highest energy content per mass among all candidate fuels, high diffusivity, and high flame speed. However, it also requires cryogenic storage and dedicated fuel supply systems for containment.

Hydrogen as a fuel has been demonstrated in internal combustion engines, gas turbines, and fuel cells, all of which will play a role in marine power generation and propulsion systems. Nevertheless, significant technical advances are needed before hydrogen can be considered a viable, large scale, commercial fuel option.

THE HEAVY GAS AND ALCOHOL PATHWAY

This category includes fuels comprised of larger molecules than the light gas group. As such, they have higher C/H ratios — therefore, lower carbon-reduction potential — and lower energy content. Their fuel storage and supply requirements are also less demanding.

These fuels include LPG, methanol, ethanol and ammonia. The alcohols tend to have lower energy content and the presence of oxygen in the fuel can create issues pertaining to chemical compatibility in fuel-supply systems.

When used as the primary fuel, methanol can reduce CO2 emissions by around 10 percent5. However,
methanol has the potential to be a carbon-neutral fuel in the future, if it is produced renewably as biomethanol or electro-methanol.

The lower energy content of some of these fuels (e.g. methanol) limits the amount of fuel energy that can be stored on board a ship; thus, they only may be suited to the types of vessels, trades and routes that allow for frequent refueling.

LPG has higher energy content than the alcohols and may be more conducive to use in modern dual-fuel engines, but it has not been as widely adopted as LNG due to its lower potential to lower emissions, and its different safety challenges.

However, methanol and LPG are currently thought of as mature fuels by engine manufacturers, which have marketed engine platforms able to use them. Therefore, they can be used to meet the carbon-reduction goals of 2030 and can pave the way to carbon-neutral propulsion, if they are produced renewably in the future.

At the end of the heavy gas or alcohol spectrum, lies ammonia, which can be a zero-carbon fuel if produced renewably. Despite its toxicity and more stringent handling requirements, ammonia engines are in the design process.

Recently, designs for ammonia-fueled feeder ships also have been unveiled by consortia that variously include designers, class and shipyards. However, for ammonia to become a commercially viable long-term fuel option, comprehensive supply-side infrastructure would need to be built and new, stringent safety regulations designed and implemented.

THE BIO/SYNTHETIC PATHWAY

This category includes fuels that are produced from biomass, including plants, waste oils and agricultural waste. Catalytic processing and upgrading of biomass can yield liquid fuels with physical and chemical properties comparable to diesel oil; this is desirable from a design standpoint because they can be used as drop-in biofuels with minimal or no changes to marine engines and their fuel delivery systems.

Currently, the most widely used component is fatty acid methyl esters (FAME) or biodiesel, which is described in the latest ISO (8217/2017) specifications for marine fuel blends and is being offered by major oil companies. The standard allows for seven percent biodiesel in the fuel blend, but some shipowners are testing richer blends, from 20 to 100 percent. FAME is a first generation biofuel and faces challenges associated with its poor oxidative stability, and its potential to degrade over time.

Hydro-treated vegetable oil (HVO) is a second generation biofuel, which is not produced from food crops. It is often referred to as renewable diesel and produced using modern hydro-treating processes, which yield high-quality fuels with better stability than FAME biodiesel.

HVO has similar physical and chemical properties to marine gas oil (MGO), making it fully compatible with existing engines and fuel-delivery systems. Renewable diesel also can be produced from biomass gasification, using the Fischer-Tropsch (FT) process. It is often referred to as a gas-to-liquid or biomass-to-liquid fuel.

Renewable diesel fuel is thought to be a promising medium- to long-term solution for shipowners, because it can offer a significant reduction in carbon output with minimal capital expenditures.

Electro-fuels: Using renewable energy to produce electro-fuels from biomass could reduce the energy required for their production, and thus reduce their life-cycle carbon footprint. This technique can be applied to any of the three fuel pathways to produce bio-LNG, bio-methanol or renewable diesel.

Electro-fuels have the potential to offer carbon-neutral propulsion and can provide solutions in the medium- to long-term. In addition to fossil and biomass sources, electro-fuels can be produced by carbon dioxide recovery (CDR), a technique that converts CO2 to syngas, which in turn can be used to produce bio-LNG or bio-methanol.

CDR has the potential to remove CO2 from the atmosphere and use it for production of electro-fuels, thereby minimizing the energy needed for fuel production and their potential to reduce global warming.

The following three sections (pages 15-40) present a detailed discussion on each fuel pathway.  READ MORE