LNG-powered ships

Authors: Dexter Keefe Widjojoatmodjo, Ved Deepak Chavan, March, 2025  

1 Description and History

1.1 Description of LNG as Marine Fuel

LNG is a colorless, odorless, and non-corrosive natural gas that has been cooled to a liquid state at approximately -162°C (-260°F) for storage and transport purposes. It primarily consists of methane (CH₄), with smaller amounts of ethane, propane, butane, and nitrogen. LNG requires larger storage volumes than conventional marine fuels like Heavy Fuel Oil (HFO) because it has a lower density than it¹.

LNG is an alternative to traditional marine fuels in the shipping transportation industry because it has environmental benefits. It substantially reduces sulfur oxides (SO_x), nitrogen oxides (NO_x), and other particulate matter emissions. Specifically, switching to LNG can reduce SO_x emissions by up to 100% and NOx emissions by up to 90% compared to HFO. Furthermore, LNG combustion produces approximately 20% less carbon dioxide than traditional fuels, contributing to efforts to mitigate climate change²

The technology that runs on LNG as a marine fuel includes dual-fuel engines capable of operating on both LNG and conventional fossil fuels. These engines use a small amount of pilot fuel, such as marine diesel oil (MDO), for initial engine ignition. There are two primary types of dual-fuel engines: high-pressure diesel cycle engines and low-pressure Otto cycle engines³:

• High-Pressure Diesel Cycle Engines

High-pressure diesel cycle engines function by initially compressing air, followed by the direct injection of LNG at substantially elevated pressures, typically ranging from 250 to 300 bar. The mixture of compressed air and LNG is ignited utilizing a limited quantity of pilot liquid fuel, such as diesel. This methodology facilitates efficient combustion and significantly enhances power output. Nonetheless, a notable disadvantage arises from the necessity to transition to pure oil fuel when operating under loads below 15 to 20%, thereby presenting challenges in maintaining low emissions within port and nearshore regions challenging.

• Low-Pressure Otto Cycle Engines

Low-pressure Otto cycle engines blend LNG with air prior to the compression process. Subsequently, this mixture undergoes compression and is ignited through pilot fuel injection. These engines function at significantly lower gas pressures, typically ranging from 5 to 7 bar, which enhances their simplicity and safety in operation. The pilot fuel utilized in these engines comprises approximately 1% of the total energy, maintaining consistency across various load ranges. This stability contributes to the preservation of low emissions even at reduced operational loads. However, these engines are prone to knocking, a phenomenon characterized by unintended ignition, which can adversely affect engine performance or potentially cause damage. The associated risk may be mitigated by increasing the air-fuel ratio and capping the engine’s power output at approximately 80% of its maximum capacity. 

1.2 Fuel Tank System

The LNG fuel tank system installed on vessels such as the KV Bergen and MF Korsfjord is engineered to uphold optimal operational conditions, ensuring fuel-efficient fuel delivery to natural gas engines. This system encompasses critical components, including the Pressure Build-Up Unit (PBU) and the Evaporator (EVAP), which are integrated within the Vaporizer. Within the PBU, LNG is vaporized and recirculated from the bottom of the tank to the top, thereby maintaining a constant operational pressure of 350 kPa. This process guarantees that the LNG remains in a suitable state for efficient combustion. The EVAP facilitates the transfer of LNG from the tank through the Vaporizer and into the natural gas engines. Additionally, waste heat generated by the vessel’s engines is harnessed within the Vaporizer via the water-glycol circuit, thereby enhancing the overall efficiency of the system efficiency⁵.

1.3 History of LNG as Marine Fuel

The utilization of liquefied natural gas (LNG) as a marine fuel can be traced back to the 1960s and 1970s, during which its application was predominantly confined to the “boil-off” gas emanating from LNG carriers. This boil-off gas, produced as LNG naturally warms and evaporates during transit, was historically employed to fuel the ship’s boilers or dual-fuel systems engines¹.

A substantial transition transpired around the year 2000, when LNG emerged as a predominant marine fuel beyond its use in LNG carriers. This shift was motivated by progressively stringent environmental regulations, including the International Maritime Organization’s (IMO) MARPOL Annex VI. These regulations sought to diminish the emissions of nitrogen oxides (NO_x), sulfur oxides (SO_x), and particulate matter from vessels. For example, in order to adhere to the Emission Control Areas (ECAs) policy, which enforced strict limitations on fuel sulfur content, the adoption of cleaner alternatives such as LNG has become one of the solutions³.

In Europe, the proliferation of LNG-fueled vessels has significantly accelerated over the past decade, primarily due to the implementation of environmental regulations in coastal regions. The European Union (EU) has been actively advocating for the adoption of LNG as a marine fuel, in alignment with its overarching objectives of mitigating greenhouse gas emissions. The EU’s 2011 White Paper on Transport has established a target to reduce emissions from maritime shipping by 40%, and, where feasible, by 50% by the year 2050, in comparison to the baseline year of 2005 levels². 

Economic and environmental factors have significantly influenced the technological advancement of LNG propulsion systems. The introduction of dual-fuel engines, which can operate on both LNG and conventional fuels, represents a notable development in this field. These engines not only provide fuel flexibility but are also engineered to comply with the stringent emission standards established by the International Maritime Organization (IMO), including the Tier III limits for nitrogen oxides (NOx), all without necessitating exhaust gas treatment systems³.

As of the year 2016, approximately 120 gas-fueled vessels were in operation; this number increased to 614 by the year 2021. The majority of these vessels are equipped with low-pressure dual-fuel engines, reflecting the industry’s preference for fuel flexibility and operational adaptability efficiency⁵.

2 Economic Performance

2.1 Development of Technology Costs

LNG has become an increasingly attractive alternative in the maritime sector due to its environmental benefits and potential cost savings. However, LNG technology adoption is influenced by capital expenditures (CapEx) and operational expenditures (OpEx).

2.2 Capital Costs

The capital expenditures associated with LNG-fueled vessels are significantly greater than those associated with conventionally fueled ships. This increased expenditure is attributable to the sophisticated propulsion systems, cryogenic double-walled fuel tanks, and specialized equipment for the storage and handling of LNG. On average, LNG-fueled vessels incur costs that are approximately 20% to 25% higher than those of their oil-fueled counterparts. The cost of an LNG tank alone can contribute between $5 million and $20 million to the overall vessel cost, depending on the size of the tank and the specifications of the engine specifications⁶.

2.3 Operational Costs

While CapEx is higher, LNG-fueled ships tend to have lower operational costs. This reduction is due to several factors, such as:

• Lower Fuel Costs: Historically, LNG prices have been lower than those of marine diesel oil (MDO) and heavy fuel oil (HFO). For instance, in 2012, LNG prices constituted approximately 16-20% of HFO prices in prominent bunkering hubs such as Fujairah Singapore⁶.
• Reduced Maintenance: LNG engines are cleaner and more efficient, leading to lower maintenance costs and longer machinery lifespans⁷.
• Fuel Efficiency: LNG engines, especially dual-fuel systems, exhibit lower specific fuel oil consumption (SFOC) compared to conventional engines. This results in additional savings over time⁶.

Despite the higher initial capital costs, the payback period for LNG-fueled ships can be reduced significantly in Emission Control Areas (ECAs) due to stricter environmental regulations and the relative affordability of LNG in the long run⁶.

2.4 Price Trends and Comparisons

The pricing dynamics of LNG as a marine fuel are intricate, shaped by factors including supply chain logistics, regional pricing mechanisms, and infrastructure development. Generally, LNG prices exhibit greater stability compared to oil-based fuels, attributed to a diversification of supply sources and the detachment from crude oil indices in certain regions markets⁶.

2.5 Bunkering and Supply Costs

The cost of delivering LNG to vessels remains a significant challenge. Bunkering infrastructure, which supplies fuel from the storage facility to vessels, is limited, and the logistics of LNG distribution can add to the final fuel price. Supply costs vary widely, ranging from $50 to $630 per ton depending on the region and method of transfer (e.g., ship-to-ship, truck-to-ship, or pipeline)⁶.

2.6 Forecasting LNG Demand

Projections indicate a consistent rise in the demand for LNG utilized for bunkering, which is further driven by global sulfur emission regulations and the maritime industry’s commitment to decarbonization. By the year 2025, it is anticipated that LNG will represent up to 3% of total bunker fuel consumption, in contrast to nearly negligible levels in previous years 2019⁹.

2.7 Industry Development and Revenue Growth

The LNG marine industry has experienced significant growth driven by heightened environmental regulations, advancements in technology, and favorable government policies. In response to the escalating demand for sustainable marine fuels, the LNG sector is rapidly evolving to align with global decarbonization efforts targets¹⁶.

2.8 Market Expansion

The market for LNG-powered vessels has been experiencing consistent growth. This trend can be attributed to the rigorous regulations set forth by the International Maritime Organization (IMO), including MARPOL Annex VI, which prioritize the reduction of sulfur and nitrogen oxide emissions. Consequently, shipping companies are increasingly allocating investments towards LNG technology, encompassing both the retrofitting of existing fleets and the commissioning of new vessels specifically designed for LNG accommodation fuels⁵.

Projections suggest that the demand for LNG bunkering, which was nearly non-existent in 2019, is anticipated to expand to approximately 3% of the total bunker fuels market by 2025 as a result of environmental regulations. Nevertheless, this growth is dependent upon pricing dynamics and the relative costs of alternative fuels fuels⁹.

2.9 Infrastructure Development and Investment

A significant barrier to the widespread adoption of LNG in marine transportation has been attributed to the inadequacy of bunkering infrastructure. The European Union, through Directive 2014/94/EU, mandates the establishment of LNG refueling stations in all major maritime and inland ports by the year 2025. This ambitious expansion of infrastructure is anticipated to substantially enhance the availability and practicality of LNG bunkering, thereby facilitating a broader acceptance within the industry adoption⁶.

Numerous significant ports, including Rotterdam and Singapore, have already developed LNG bunkering facilities, which provide financial incentives such as rebates and reduced registration fees for vessels powered by LNG. Consequently, this has resulted in an increase in the number of LNG-fueled vessels operating within emission control areas (ECAs), where more stringent environmental standards are enforced apply⁶.

2.10 Revenue Growth and Economic Performance

Investments in LNG infrastructure and technology are projected to yield substantial revenue growth in the industry. It is anticipated that investments amounting to up to $200 billion will be made over the next five years to enhance production, distribution, and bunkering capabilities⁶. This investment is expected to increase global LNG production by 50%, addressing the increasing demand for cleaner maritime solutions fuels.

Moreover, LNG-fueled vessels are increasingly becoming competitive owing to their lower operational costs relative to those utilizing conventional fuels. Despite higher initial capital expenditures—largely attributed to the installation of cryogenic storage tanks and specialized propulsion systems—LNG vessels experience reduced fuel expenses, diminished maintenance costs, and extended machinery durability. Consequently, this yields a favorable total cost of ownership over the lifespan of the vessel, especially for ships operating in ECAs⁶.

2.11 Government Incentives and Policy Support

Government policies exert a considerable influence on the expedited adoption of LNG as a marine fuel. An illustration of this can be observed in the European Union’s Trans-European Transport Network (TEN-T) initiative, which has allocated funding for the advancement of LNG bunkering infrastructure in vital maritime regions hubs⁷. Countries like Norway have also established funds such as the NOx Fund, which supports investments in low-emission fuels, including LNG⁶.

3 Ecological Performance and Environmental Impact

The environmental performance of LNG as a marine fuel has garnered significant attention in the endeavor to diminish greenhouse gas (GHG) emissions and other pollutants associated with maritime operations. Although LNG offers notable environmental advantages in comparison to conventional marine fuels such as Heavy Fuel Oil (HFO) and Marine Diesel Oil (MDO), its comprehensive ecological impact is intricate, taking into account aspects such as methane slip and upstream processes emissions.

3.1 Greenhouse Gas Emissions

Vessels powered by LNG have showcased considerable potential for mitigating greenhouse gas (GHG) emissions in comparison to conventional marine fuels. Research suggests that High-Pressure Dual Fuel (HPDF) LNG engines can diminish GHG emissions by as much as 28% over a 100-year Global Warming Potential (GWP) when evaluated against Heavy Fuel Oil (HFO). Conversely, low-pressure dual fuel (LPDF) two-stroke engines can achieve reductions of up to 18%. The enhanced efficiency of these engines contributes to reduced fuel consumption, thereby leading to diminished carbon dioxide (CO₂) emissions. For example, the combustion of LNG results in approximately 25% less CO₂ emission than traditional marine fuels when assessed on a Tank-to-Wake (TTW) basis, attributable to its elevated hydrogen-to-carbon ratio¹⁷.

Nevertheless, an assessment of Well-to-Tank (WTT) emissions—encompassing the extraction, processing, and transportation of LNG—indicates that its ecological benefits are not as clear-cut. The upstream emissions, especially methane leaks occurring during production and transportation, may considerably diminish these advantages. Methane is recognized as a potent greenhouse gas, possessing a Global Warming Potential (GWP) that is 86 times greater than CO₂over a two-decade horizon¹¹. This short-term impact is crucial because unburned methane from engine slip can compromise the long-term environmental benefits of LNG.

3.2 Methane Slip and Its Implications

Methane slip refers to the unburned methane emitted from a ship’s engine, which presents a significant issue for LNG-fueled vessels, especially those utilizing low-pressure injection systems. Lean Burn Spark-Ignited (LBSI) engines demonstrate methane slips of approximately 4.1 gCH4/kWh, whereas LPDF four-stroke engines exhibit slips ranging from 2.5 to 3.1% by weight of fuel consumed¹¹. This error can negate the GHG benefits of LNG, especially when assessed over a 20-year GWP basis¹³.

High-Pressure Dual Fuel (HPDF) engines present a viable option, demonstrating notably reduced methane emissions of about 0.2 gCH4/kWh¹¹. Despite this advantage, adopting HPDF engines is not yet widespread due to higher costs and technical complexities.

3.3 Comparative Analysis with Conventional Fuels

When evaluating LNG in comparison to conventional marine fuels such as heavy fuel oil (HFO), very low sulfur fuel oil (VLSFO), and marine gasoil (MGO), it reveals significant advantages and disadvantages. From a Well-to-Hull perspective, LNG exhibits lower carbon dioxide emissions (11.0 g/MJ) in contrast to HFO (10.7 g/MJ); however, it results in elevated total CO2-equivalent emissions when methane is considered, particularly under a 20-year Global Warming Potential (GWP) assessment scenario¹¹.

Moreover, the combustion of LNG yields minimal sulfur oxide (SOx) emissions due to the absence of sulfur in LNG. This leads to a substantially reduced output of particulate matter (PM) and nitrogen oxide (NOx) emissions, rendering LNG a compelling option for compliance with stringent emission regulations, including the sulfur cap established by the International Maritime Organization (IMO) and the designated NOx emission control areas (ECAs)^17,10.

3.4 Resource Use and Lifecycle Considerations

The extraction, liquefaction, and transportation of LNG necessitate considerable energy resources, thereby influencing its environmental footprint as a marine fuel. It is noteworthy that the liquefaction process, which converts natural gas into a liquid state, requires a substantial amount of energy, consequently elevating the lifecycle emissions in comparison to natural gas that is delivered through pipelines gas¹¹.

Despite these challenges, LNG remains a transitional fuel in the maritime sector’s transition toward decarbonization. The evolution of renewable LNG (bio-LNG) and progress in methane capture and reduction technologies are expected to enhance the environmental performance of LNG future¹².

3.5  Ecological Performance Over Time

The ecological performance of LNG-powered ships has significantly improved over the years, thanks to advancements in engine technology, stricter regulations, and better emissions control strategies. Initially seen as a cleaner alternative to traditional marine fuels, LNG has undergone continued scrutiny and refinement, revealing both environmental benefits and challenges. This section explores the key metrics, trends, and technological innovations that have shaped LNG’s role in reducing maritime emissions and enhancing sustainability.

3.6 Reduction in Greenhouse Gas Emissions

One of the primary reasons for the shift toward LNG in the maritime industry is its potential to lower greenhouse gas (GHG) emissions. Compared to traditional fuels like Heavy Fuel Oil (HFO) and Marine Diesel Oil (MDO), LNG combustion results in approximately 20-25% lower CO₂ emissions on a Tank-to-Wake (TTW) basis, primarily due to its higher hydrogen-to-carbon ratio¹⁸. However, LNG’s total environmental benefits depend not just on combustion emissions but also on its full lifecycle impact, including emissions from extraction, liquefaction, and transportation. One of the biggest challenges has been methane slip, which refers to the unburned methane that escapes during engine combustion. Early Low-Pressure Dual-Fuel (LPDF) engines exhibited methane slip rates of 2.5–3.1% of the fuel consumed by weight, which diminished LNG’s climate advantage because methane has a Global Warming Potential (GWP) 86 times higher than CO₂ over a 20-year period¹⁹. To address this issue, newer High-Pressure Dual-Fuel (HPDF) engines have been developed, which significantly reduce methane emissions. Modern HPDF engines have achieved methane slip levels as low as 0.2 gCH₄/kWh¹⁸, making them far more environmentally friendly.

In addition to engine improvements, mitigation strategies like methane oxidation catalysts and exhaust gas recirculation have been introduced, further enhancing LNG’s environmental performance²⁰.

3.7 Lifecycle Emissions and Resource Use

A detailed environmental assessment of LNG requires looking at emissions across its entire lifecycle, from production to consumption—often referred to as the Well-to-Wake (WTW) perspective. While LNG’s direct CO₂ emissions are lower, its total lifecycle emissions vary depending on how it is produced, transported, and used.

Studies indicate that WTW GHG emissions for LNG range between 69-90 gCO₂e/MJ, while HFO falls between 80-95 gCO₂e/MJ²⁰. The main reason for this variation is methane leakage during LNG extraction, processing, and transportation, making it essential to improve supply chain efficiency to maximize environmental benefits.

The introduction of bio-LNG and synthetic LNG is expected to revolutionize the industry by cutting lifecycle emissions by up to 90%, making LNG a more sustainable marine fuel²¹. Additionally, better liquefaction technology and optimized transportation routes have gradually reduced the energy intensity of LNG production²⁰.

3.8 Regulatory Influence on Environmental Performance

The maritime industry has undergone major regulatory shifts to tackle emissions, directly influencing LNG adoption. One of the most significant regulations is the IMO 2020 sulfur cap, which mandated a 99% reduction in sulfur oxide (SOₓ) emissions²². This made LNG an attractive option for shipping companies looking to comply with stricter environmental laws.

Further policies, such as the Energy Efficiency Existing Ship Index (EEXI) and the Carbon Intensity Indicator (CII), have pushed shipowners toward fuel efficiency measures and alternative fuels²³. As a result, LNG-powered vessels are now integrating hybrid propulsion solutions—such as LNG-battery hybrid systems—which reduce fuel consumption by 15-20% and further cut emissions²⁴.

In addition to engine technology, digital optimization tools are playing a growing role in improving LNG efficiency. Advanced voyage planning software helps reduce unnecessary fuel burn, further enhancing LNG’s sustainability profile²³.

3.9 Technological Advancements and Future Prospects

The ongoing technological evolution of LNG engines has continued to improve environmental performance. The development of methane oxidation catalysts has helped reduce methane slip by up to 70% in some applications²⁵.

Moreover, advancements in engine efficiency, waste heat recovery, and LNG-hybrid propulsion systems are helping to further cut emissions²⁴.

Looking ahead, the adoption of carbon capture and storage (CCS) technologies on LNG-powered ships is expected to reduce emissions by 30-40% over the next decade²⁶. Additionally, the integration of bio-LNG and synthetic LNG from renewable sources will continue lowering GHG emissions, ensuring that LNG remains a crucial part of the transition to clean maritime energy²⁶.

4 Social Impact of LNG-Powered Ships

The social acceptance and impact of LNG-powered ships have evolved considerably over the years. As LNG has gained traction as a cleaner alternative to traditional marine fuels, it has brought both positive and negative social implications. While LNG-powered shipping has created new jobs and improved public health, concerns over noise pollution and community resistance remain.

4.1 Social Acceptance and Changing Perceptions

The public perception of LNG-powered ships has shifted significantly over time, influenced by environmental awareness, economic factors, and regulatory policies. Initially, LNG faced skepticism due to concerns about methane slip and its overall sustainability. Many stakeholders questioned whether LNG was truly a green solution or just another fossil fuel with hidden environmental drawbacks.

However, with advancements in emissions reduction technology and stricter maritime regulations, LNG has gained broader acceptance, especially in Europe, North America, and parts of Asia²⁷. One of the biggest factors in its acceptance has been its role in helping the shipping industry meet global emissions targets. The International Maritime Organization (IMO) has set stringent air pollution limits, and LNG-powered ships contribute to meeting these targets by reducing sulfur oxide (SOₓ) emissions by 99% and nitrogen oxides (NOₓ) by 85% compared to traditional fuels²⁸. As awareness of LNG’s air quality benefits and regulatory compliance has grown, so has public and industry support.

4.2 Positive Social Impacts

Job Creation and Economic Opportunities: 

The transition to LNG-powered ships has created thousands of new jobs across various industries, particularly in shipbuilding, port operations, and engineering. The increasing demand for LNG bunkering, maintenance, and fuel logistics has led to a specialized workforce emerging in these sectors²⁹. The development of LNG infrastructure, including bunkering hubs in Singapore, Rotterdam, and the U.S. Gulf Coast, has further boosted employment opportunities³⁰. As more ports invest in LNG fueling stations and supply chains, the economic ripple effect continues to expand, benefiting both skilled and semi-skilled workers.

Public Health Benefits and Reduced Mortality:

The shift to LNG has led to significant improvements in air quality, especially in busy port cities where air pollution from shipping was a major public health concern. LNG-powered ships have contributed to a 91% reduction in particulate matter (PM) emissions in high-traffic port areas such as Los Angeles, Shanghai, and Hamburg³¹.

This improvement in air quality has had direct health benefits, including:

• Fewer cases of respiratory diseases such as asthma and bronchitis.
• Lower incidence of premature deaths linked to long-term exposure to air pollution.
• Improved overall well-being of communities living near major shipping hubs.

For many coastal and port cities, the transition to LNG-powered vessels represents a major step toward cleaner air and healthier communities.

Reduction of Social Inequality:

One of the lesser-discussed social benefits of LNG is its role in reducing environmental inequality. Coastal and port communities—many of which are low-income areas disproportionately affected by shipping emissions—have benefited the most from the transition to LNG.

By cutting SOₓ, NOₓ, and PM emissions, LNG-powered vessels have helped improve air quality in these regions, leading to:

• Better health outcomes for vulnerable populations.
• Reduced healthcare costs associated with pollution-related diseases.
• More equitable living conditions between coastal and inland communities.

For many, LNG adoption represents a step toward environmental justice, ensuring that poorer communities no longer bear the brunt of shipping-related air pollution.

4.3 Negative Social Impacts

Noise Pollution and Community Concerns:

LNG-powered ships generate noise pollution, particularly during bunkering operations and regasification. Increased LNG terminal activities in populated coastal regions have led to complaints about noise disturbances, which can negatively affect both residents and marine wildlife.

Safety Risks and Public Perception:

Despite stringent safety measures, public concerns about LNG leaks, explosions, and accidents persist. The flammable nature of LNG has led to resistance from communities near LNG bunkering facilities and terminals. In some regions, local opposition to LNG infrastructure projects has delayed or restricted their development due to concerns about environmental risks and safety hazards.

5 Political and Legal Aspects

The development and adoption of LNG-powered ships have been shaped significantly by government policies, international regulations, and legal frameworks. Various global, regional, and national policies have encouraged the transition to LNG as a marine fuel, while debates continue regarding the long-term viability of LNG compared to alternative low-carbon fuels.

5.1 Key Policies Shaping LNG-Powered Ship Development

International Regulations

The IMO 2020 sulfur cap has been a major driver of LNG adoption, requiring ships to use fuels with less than 0.5% sulfur content or implement alternative solutions like scrubbers or LNG. Additionally, the IMO’s Energy Efficiency Existing Ship Index (EEXI) and Carbon Intensity Indicator (CII) have pushed ship operators toward LNG to meet new efficiency and emissions targets.

National and Regional LNG Policies

Different countries have implemented policies to promote LNG adoption in maritime transport:

• European Union (EU): The FuelEU Maritime Initiative encourages the transition to low-carbon fuels, including LNG, through financial incentives and infrastructure investments.
• United States: The U.S. Clean Air Act and California’s shore power regulations have incentivized LNG use in ports to meet strict air quality standards.
• China: Government subsidies for LNG bunkering and port infrastructure development have contributed to the rapid adoption of LNG in Chinese shipping fleets.

5.2 Pros and Cons of Alternative Policies:

Advantages of LNG Policies

○      Improved air quality and health benefits from reduced emissions²⁸.

○      Compliance with global climate goals through lower GHG emissions compared to traditional marine fuels.

○      Encourages investment in LNG infrastructure, creating new economic opportunities³⁰.

●      Challenges and Criticisms

○      Methane Slip Concerns: Critics argue that methane slip from LNG engines offsets some of the climate benefits, questioning whether LNG is truly a long-term solution for decarbonization.

○      Infrastructure Costs: Building LNG bunkering stations and storage facilities requires significant investment, limiting adoption in some regions.

○      Policy Uncertainty: Some governments are now shifting focus toward zero-carbon alternatives like green hydrogen and ammonia, raising concerns about the future viability of LNG investments.

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