Sustainability-Oriented Port Management: Biomass Gasification as a Strategic Tool for Green and Circular Maritime Logistics

Abstract

The maritime industry faces growing pressure to reduce greenhouse gas emissions and adopt sustainable practices. Ports, as critical logistics hubs, can drive this transition. This review aims to assess biomass gasification as a strategic tool for sustainable port management, highlighting its role in reducing fossil fuel dependency and promoting circular economy principles. Using a thematic review approach, recent advancements in gasification technology are analyzed alongside environmental, economic, and social impacts. However, key barriers, such as feedstock variability, high capital costs, and fragmented policies, hinder widespread adoption. Proposed solutions emphasize policy integration, stakeholder collaboration, and hybrid energy approaches. Case studies demonstrate successful implementations, reinforcing biomass gasification’s role in achieving greener, more resilient port operations. These insights provide a strategic foundation for policymakers and industry stakeholders.

1. Introduction

The global maritime industry is a key facilitator of international trade and economic growth, with ports acting as vital nodes in this vast logistics network [1]. However, the environmental impacts of maritime operations, including significant greenhouse gas (GHG) emissions, air pollution, and disruption of marine ecosystems, are putting sustainability at the forefront of the industry discourse [2]. Although maritime transport currently accounts for approximately 3% of global carbon dioxide (CO₂) emissions, this is expected to increase remarkably by 2050 if not properly managed [3,4]. Ports, being central to the industry, have the potential to lead green initiatives. Therefore, sustainable port management has emerged as a key focus area for ensuring long-term environmental and economic viability [5].

Sustainability in port management refers to policies and practices that aim to reduce environmental impact while increasing operational efficiency and economic viability. In response to growing regulatory pressures and global sustainability goals, ports are increasingly adopting measures such as emission reduction strategies, renewable energy integration, circular economy models, and advanced waste management systems [6]. While these initiatives require high upfront costs they offer long-term economic and environmental benefits by reducing resource consumption, improving operational efficiency, and enhancing market competitiveness [7]. Dvorak and Burkšienė [8] further highlight the interconnected nature of sustainability factors in port operations, emphasizing that environmental management cannot be divorced from other aspects such as security and economic considerations. This holistic approach underscores the complexity of sustainable port management and the need for integrated strategies that address multiple dimensions of sustainability simultaneously.

Recent advancements in decarbonization have brought critical insights into how ports can take a leading role in sustainable practices. One such development focuses on the role of green hydrogen in decarbonizing industrial port areas and maritime logistics. As ports are responsible for a large proportion of GHG emissions, particularly from hard-to-abate sectors like shipping, integrating hydrogen-based technologies offers significant potential in mitigating these emissions. Hydrogen serves as a renewable energy carrier, capable of powering port operations and machinery while reducing dependence on fossil fuels. Onshore power supplies (OPSs) powered by hydrogen, for example, have emerged as a promising strategy for reducing pollution from ships while berthed, which are responsible for over 70% of port emissions. By incorporating hydrogen technologies into port infrastructure, ports can further reduce their carbon footprints and strengthen their energy resilience, aligning with sustainability goals [9,10].

Additionally, recent research on port decarbonization strategies highlights the significance of combining technological innovations with effective policy frameworks to achieve sustainability. The study by Yildiz et al. [11] underlines that decarbonization in ports is most successful when innovative technologies, such as alternative fuels and energy-efficient solutions, are integrated with regulatory support and operational strategies. For instance, the adoption of renewable energy sources like wind and solar, along with energy-efficient technologies, is crucial for reducing fossil fuel reliance in port operations. Furthermore, strategic operational improvements, such as optimizing port logistics and reducing emissions from equipment and vehicles, are critical to minimizing environmental impact while maintaining operational efficiency.

Despite ongoing efforts, sustainable port management remains fragmented, as ports continue to rely on traditional fossil-fuel-based infrastructure and resource-intensive practices that limit their transition to low-carbon and circular economy models [12]. Existing research has largely focused on emissions control, port security, and infrastructure development, but there remains a significant gap in exploring how renewable energy solutions, particularly waste-to-energy technologies, can be systematically integrated into port sustainability strategies.

One promising yet underutilized solution within sustainable port management is biomass gasification, a process that thermochemically converts organic materials into syngas, a blend composed mostly of hydrogen and carbon monoxide and in minor amounts some other valuable gases [13]. This renewable energy source has the potential to replace fossil fuels in port operations, powering machinery and electrical systems while reducing dependence on non-renewable resources [14]. Furthermore, biomass gasification aligns with circular economy principles by transforming waste streams, such as plastic waste, food waste, packaging materials, and shipboard waste, into high-value energy vectors. This approach not only reduces landfill dependency and waste disposal costs but also turns environmental liabilities into economic and ecological assets [15].

From a strategic standpoint, using biomass gasification in port management offers multiple benefits. It improves ports’ energy resilience by reducing dependence on external energy grids, mitigating carbon emissions, and strengthening compliance with increasingly strict environmental regulations [16]. Additionally, green ports that leverage technologies like biomass gasification are better positioned to attract environmentally conscious stakeholders, including shipping companies, investors, and customers, giving them a competitive advantage in the global market [17].

While previous research has explored biomass gasification in the context of bioenergy and waste-to-energy applications, its strategic integration within sustainable port operations remains largely unexplored. The majority of studies on gasification focus on technical and engineering aspects rather than its role in broader port sustainability strategies. As a result, there is limited understanding of how ports can leverage biomass gasification to enhance overall sustainability, circularity, and energy resilience. This study differentiates itself by not only analyzing biomass gasification as an energy technology but by situating it within a comprehensive approach to sustainable port management. Instead of treating biomass gasification as a standalone waste-to-energy solution, this review examines how it can be systematically integrated into broader sustainability strategies for ports, including policy adaptation, regulatory alignment, economic feasibility, and circular economy principles. By addressing this gap, the study provides strategic insights into how ports can transition toward energy-efficient and environmentally responsible operations.

Given the need to bridge the gap between energy transition strategies and sustainable port management, this literature review aims to investigate biomass gasification as a strategic tool for green and circular maritime logistics. Specifically, this study seeks to answer the following research questions:

i.

How can biomass gasification be integrated into sustainable port management strategies to enhance energy efficiency, waste valorization, and emissions reduction?

ii.

What are the key technical, economic, and policy challenges affecting the adoption of biomass gasification in ports, and how can they be addressed to promote a circular maritime economy?

Overall, by synthesizing existing research, this study provides insights into how biomass gasification can serve within a holistic port sustainability model, rather than being viewed as an isolated technological intervention. The findings aim to contribute to ongoing discussions on maritime decarbonization, circular economy integration, and the long-term sustainability of port infrastructure.

2. Research Approach

This study utilizes a thematic review methodology to investigate the role of biomass gasification in advancing sustainability within port management and maritime logistics. Unlike systematic reviews, which adhere to a structured protocol with rigid inclusion and exclusion criteria, a thematic review approach is more flexible, allowing for the synthesis of knowledge from diverse academic, industry, and policy sources. This method is particularly suited to emerging interdisciplinary topics, as it facilitates the identification of key themes, conceptual linkages, and research gaps across multiple disciplines. The research approach follows three key stages: Literature Search and Data Collection, Themes Categorization, and Critical Analysis and Synthesis. The methodology is delineated in the following steps:

2.1. Literature Search and Data Collection

A literature search was conducted to collect relevant studies, reports, and policy documents, ensuring a broad and multidisciplinary perspective on the use of biomass gasification in ports and maritime logistics. In line with the thematic review approach, the selection process prioritized relevance and credibility rather than imposing rigid inclusion/exclusion criteria or time frame restrictions. This approach ensures that both foundational studies and recent advancements are considered to provide a comprehensive and multidisciplinary perspective on the topic.

To maintain academic credibility and reliability while allowing for flexibility in the selection process, the literature was assessed based on the following key quality assessment criteria. These criteria functioned as guiding principles to ensure the inclusion of high-quality and thematically relevant sources, rather than as rigid exclusionary rules that might limit valuable insights:

• Thematic Relevance: Sources were selected based on their direct relevance to biomass gasification, sustainable port management, and maritime logistics. Studies on general biomass technologies were considered if they provided transferable insights applicable to port operations;
• Credibility of Publication Outlets: Peer-reviewed journal articles and conference proceedings were prioritized;
• Evidence-Based Contributions: Preference was given to studies that demonstrated empirical evidence, methodological rigor, or technical analysis, including experimental research, lifecycle assessments, techno-economic evaluations, and case studies on biomass gasification;
• Academic Impact and Recognition: Frequently cited studies were considered significant contributions to the field, but newer studies were also included if they introduced novel insights or emerging trends in biomass gasification and port sustainability;
• Reliability of Industry and Policy Reports: Reports were included only if published by governmental agencies, regulatory bodies, or internationally recognized organizations, ensuring credibility.
• The primary sources of information were:
• Academic Databases: Scopus, Web of Science, and Google Scholar, which provided peer-reviewed journal articles, conference proceedings, and technical work on biomass gasification, sustainable port management, and maritime logistics.

To support the academic literature, additional references were used from the following sources:

• Industry Reports and Policy Documents: Publications from port authorities, government agencies, and industry stakeholders, such as reports on port sustainability initiatives, renewable energy adoption, and waste-to-energy strategies;
• Credible Web Sources: Reports and articles from recognized organizations such as the International Maritime Organization (IMO), the European Commission, the International Renewable Energy Agency (IRENA), and the United Nations (UN).

This diverse sourcing strategy ensures a thorough dataset, merging insights from scientific research, industry practices, and global policy frameworks.

2.2. Data Extraction and Thematic Categorization

Following the literature search, relevant studies were systematically examined to extract key insights regarding biomass gasification in the context of sustainable port management and maritime logistics. A thematic categorization was then conducted to structure the analysis effectively. The themes identified include biomass gasification fundamentals, recent technological advancements, sustainability assessment, key energy demands in ports and integration opportunities, policy and regulatory frameworks, real-world projects and case studies, risk assessment, and future research directions. This categorization provided a holistic synthesis of the literature, incorporating technical, economic, environmental, social, and policy-oriented viewpoints.

2.3. Analysis and Synthesis of Findings

The final stage involved an assessment and synthesis of the categorized literature to offer a holistic perspective on biomass gasification’s role in maritime logistics. The analysis identified the main advantages, such as emissions reduction, energy independence, and waste valorization. However, it also brought to light several challenges, such as substantial initial investments, regulatory constraints, and feedstock availability. The policy implications were scrutinized, with an emphasis on regulatory facilitators, financial incentives, and the collaborative efforts of government and industry in promoting adoption. Additionally, integration strategies were explored, assessing how biomass gasification could enhance port energy resilience and contribute to decarbonization goals.

The analysis of social dimensions was also conducted, focusing on public health benefits, job creation, and community engagement in renewable energy adoption. The role of biomass gasification in improving energy security for coastal communities and its potential to create skilled employment opportunities within the maritime sector were considered. Risk assessment findings informed mitigation strategies, underscoring the importance of technological advancements, stable policy frameworks, and investment incentives. Lastly, future research priorities were identified, highlighting the need for advancements in AI-driven optimization, novel biomass feedstocks, and stakeholder-driven policy frameworks. This synthesis provides a well-structured framework for comprehending the feasibility, advantages, and challenges associated with biomass gasification in achieving sustainable port operations.

Figure 1 illustrates the thematic review methodology, outlining the sequential stages of literature search, data extraction, and findings synthesis.

3. Biomass Gasification Fundamentals

Biomass gasification is a thermochemical process that converts organic materials into a combustible gas mixture called producer gas, that can be then upgraded to syngas [18]. This process occurs at high temperatures in a controlled reactive environment with limited, or even without, oxygen (O₂) [19]. Syngas has been defined as a gas mixture composed primarily of hydrogen (H₂) and carbon monoxide (CO) and other minor concentrations of methane (CH₄), water vapor (H₂O), and small amounts of other hydrocarbons and inert gases [20]. In addition to syngas, biomass gasification produces char and ash as solid products [21,22]. The properties of char and ash vary depending on feedstock and gasification conditions [23]. The char and ash can be utilized as catalysts, soil amendments, or for energy production [24].

The process typically involves four stages. The initial phase is drying, during which the moisture content of the biomass is diminished through exposure to heat, generally at temperatures ranging from 100 to 200 °C. Following this, the pyrolysis phase takes place, where the breakdown of the solid structure releases volatile substances, resulting in the formation of several gas compounds and tars. Thereafter, and following a simplified approach, oxidation reactions (exothermal) produce CO, CO₂, and H₂O, and reduction reactions (mostly endothermal) convert carbon in char, CO₂, and water vapor into CO and H₂, among other gas compounds (e.g., CH₄ and other light hydrocarbons), that consist of the producer gas precursor of syngas [25,26,27]. The syngas obtained from gasification has a wide range of applications. It can be employed for electricity production by being directly utilized in internal combustion engines, gas turbines, and fuel cells. Furthermore, syngas acts as an intermediate for generating synthetic fuels and chemicals in biofuel production. It is also applicable for industrial heating, serving as an alternative to fossil fuels in numerous industrial processes [28,29].

The quality and composition of syngas are profoundly affected by feedstock properties, reactor type, and operational conditions. The equivalence ratio (ER), defined as the ratio of the actual oxygen supplied to the fuel to the oxygen required for complete combustion of theoretical biomass, is one of the most critical parameters in gasification. An optimal ER range of 0.2 to 0.3 has been identified for maximizing gasification efficiency, as it balances partial oxidation reactions to enhance syngas yield and quality while preventing excessive combustion losses. At ER values below 0.2, incomplete gasification leads to higher char formation and lower syngas production, whereas ER values above 0.3 promote over-oxidation, increasing CO₂ content and reducing the calorific value of syngas. This range has been found to be effective across various biomass types, though slight variations may occur depending on specific feedstock properties and reactor configurations.

Moreover, higher gasification temperatures generally lead to increased syngas yield and H₂ concentration [30,31,32]. An increase in the steam-to-biomass ratio can also improve H₂ concentration; however, excessively high ratios may reduce the calorific value of syngas due to excessive steam dilution [31,33]. Additionally, feedstock characteristics, such as moisture content and ash composition, directly impact syngas yield and quality, as variations in volatile matter and inorganic components can influence gasification reactions [30]. Different reactor types also produce varying amounts and compositions of syngas from biomass due to differences in gas–solid interactions, residence time, and temperature distributions [34].

Biomass gasifiers are classified based on their operating principles and design configurations. Fixed-bed gasifiers, including updraft, downdraft, and crossdraft designs, offer simplicity but often produce higher tar content. Updraft gasifiers are capable of processing biomass with significant ash and moisture content, whereas downdraft gasifiers are recognized for producing lower tar levels [35]. Therefore, downdraft gasifier types are favored for small-scale applications due to their easy design, minimal tar output, and controllable operations [36]. Fluidized-bed gasifiers ensure consistent temperature distribution and higher conversion efficiency, ideal for large-scale operation. Entrained-flow gasifiers function at elevated temperatures and pressures, resulting in the production of high-quality syngas but requiring complex feedstock preparation [37]. The choice of a specific gasifier type depends on various factors such as end-use requirements, fuel characteristics, and the quality of gas desired [38].

The process is compatible with a variety of feedstocks, each with specific advantages based on their physical and chemical properties. Woody biomass, such as wood chips, sawdust, and forest residues, is one of the most suitable feedstocks for gasification due to its low moisture and ash content, which contributes to the production of high-quality syngas [14]. Agricultural residues, including rice husks, wheat straw, corn, and sugarcane bagasse, are abundant and cost-effective options. However, they may contain higher levels of ash, requiring gasifier designs that can effectively manage slag formation [18]. Energy crops like switchgrass, miscanthus, and poplar are purpose-grown for bioenergy applications. These crops provide consistent quality and high yields, making them particularly reliable for gasification systems [39]. Biodegradable waste, such as food waste, sewage sludge, and animal manure, can also serve as gasification feedstock. While these materials often require pre-treatment or drying to reduce moisture content, they offer the added benefit of supporting circular economy practices and waste management goals [40]. In addition, lignocellulosic residues such as coconut shells and palm kernel shells are suitable for gasification. These materials have high energy density and low nitrogen content, which minimizes the production of undesirable compounds during the process [27]. This diverse feedstock highlights the flexibility of gasification technology in efficiently utilizing a wide range of biomass sources.

4. Recent Advancements in Biomass Gasification

Biomass gasification has experienced considerable technological progress in recent years, motivated by the demand for more efficient, sustainable, and economically feasible energy alternatives. These advancements seek to tackle critical issues such as feedstock variability, tar production, and system scalability, while enhancing the overall efficiency and environmental impact of gasification systems.

Recent developments in gasifier designs, such as fluidized bed and entrained flow gasifiers, have significantly improved the capacity to utilize a diverse array of feedstocks, such as agricultural by-products, woody biomass, and municipal solid waste. These innovative designs provide superior temperature regulation and enhanced conversion efficiencies, rendering them appropriate for extensive applications in ports and maritime logistics [18,39]. Furthermore, multistage gasification processes that combine pyrolysis and gasification have been introduced to improve syngas production and operational flexibility [41].

Waste-to-energy applications have also gained momentum, propelled by the increasing need for sustainable waste management solutions. The use of municipal solid waste and industrial waste as feedstock for gasification has been enhanced by advancements in waste pre-treatment technologies, such as drying and pelletization, which have improved the efficiency of gasification systems using waste feedstocks [42]. The BioSferA project in Europe has successfully showcased the production of biofuels from syngas obtained from waste biomass, providing a scalable solution for ports seeking to minimize landfill reliance and generate renewable energy [43]. Moreover, the concept of polygeneration, which involves producing multiple energy products such as heat, power, and biofuels from biomass gasification, has improved the economic feasibility and resource utilization of the technology, making it an increasingly attractive option for sustainable energy production [44,45].

To tackle the persistent issue of tar formation, recent developments in catalytic tar cracking and plasma-assisted gasification have demonstrated promising outcomes as well. For example, nickel-based and olivine catalysts have proven effective in decomposing tar into simpler gases, thereby enhancing the quality of syngas [46]. Plasma gasification, on the other hand, not only reduces tar but also enhances H₂ production, making it a viable option for clean energy generation [47]. The Taylor Gasification Process, developed by Taylor Biomass Energy, also offers significant improvements in biomass gasification by incorporating in situ tar destruction. This process utilizes a unique gas conditioning step that converts tars into additional synthesis gas and adjusts its composition, resulting in a tar removal rate of approximately 90% [48].

Beyond tar removal, other contaminants in syngas, such as sulfur compounds, ammonia, and particulates, require effective purification techniques. Desulfurization is commonly achieved using metal-based sorbents, which capture hydrogen sulfide (H₂S) and convert it into stable compounds. ZnO-based sorbents have emerged as promising alternatives to conventional amine-based processes, offering sulfur removal over a wide temperature range (260–760 °C) and reduced complexity [49]. Novel approaches include eutectic mixtures of metal oxides and unsupported mixed oxides, which demonstrate rapid absorption kinetics and high capacity. Additionally, new nanostructured sorbents such as nickel–copper nanoparticles in mesoporous silica have demonstrated significant sulfur removal capabilities [50]. Ammonia is often removed through scrubbing techniques, including water-based absorption and catalytic reforming. A process development unit at Iowa State University has demonstrated effective ammonia removal using water scrubbing, achieving target concentrations as low as 1 ppm [51]. Advanced catalytic oxidation and selective ammonia decomposition techniques are also being explored to minimize NO_x formation when syngas is used for combustion [52]. Furthermore, high-temperature ceramic filters, cyclone separators, and candle filters are effective in removing fine particulates from syngas. Recent studies have highlighted the potential of Mn/Ce-oxide-coated fibrous filters for simultaneous dust removal and NO_x reduction, achieving nearly 100% particulate removal for particles larger than 4 µm [53]. Warm gas filtration technologies, including high-efficiency candle filters and vortex separators, have also shown promise in improving syngas quality while maintaining high-temperature operations [54].

The integration of biomass gasification with carbon capture and storage technologies has also gained attention as a way to attain negative carbon emissions. By capturing CO₂ from the gasification process and storing it underground, these systems can contribute to decarbonization efforts in the maritime sector. For example, the bioenergy with carbon capture and storage (BECCS) approach has been successfully demonstrated in pilot projects, showing potential for large-scale deployment in ports and industrial hubs [55,56]. Dual fluidized bed steam gasification is another advanced technology for producing hydrogen-rich syngas from biomass while enabling CO₂ capture. This process uses steam as a gasification agent and circulates hot bed material between two reactors for heat transfer [57].

In addition, recent research demonstrates how digitalization and process optimization have transformed biomass gasification. Advanced control systems and digital technologies are now being implemented in commercial applications [58]. Real-time monitoring systems using differential temperature profiling and Internet of Things (IoT) technologies enable precise control of gasification processes, leading to more stable operations and consistent syngas properties. These systems allow for instantaneous adjustments of parameters such as air-to-fuel ratio and fuel feeding rate, significantly reducing fluctuations in temperature, gas composition, and tar concentration [59,60]. Artificial intelligence (AI) methods can also accurately simulate gasification outcomes based on real datasets, considering factors like temperature and fuel composition [61]. XGBoost regression models have been used to analyze input feature importance and simulate biomass gasification systems, with equivalence ratio, volatile matter, and lower heating value identified as top features [62]. Furthermore, machine learning algorithms like random forest, combined with Monte Carlo simulations and kinetic modeling, have shown capability to predict optimal gasification process parameters for maximum syngas yield [63]. These advancements in monitoring, control, and optimization techniques have greatly improved the efficiency and reliability of biomass gasification processes across various gasifier types and scales.

5. Sustainability Assessment of Biomass Gasification in Ports

This section examines the wide-ranging implications of biomass gasification in ports, highlighting its potential to advance sustainability by integrating environmental, economic, and social benefits into maritime operations and energy systems.

5.1. Environmental Impact

The environmental aspect of sustainability in port management is crucial, as ports play a major role in global emissions due to considerable useful energy consumption and emissions from ships and cargo-handling machinery, along with other associated operations. To tackle these issues, ports are implementing innovative strategies to decrease their carbon footprint and boost environmental performance.

Biomass gasification stands out as a practical and impactful strategy to enhance environmental sustainability in ports and shipping operations. Studies indicate that biomass gasification can substantially lower GHG emissions compared to conventional energy sources. For instance, a 10 MW biomass gasification plant in Malaysia achieved reductions of 17,863 tons of CO₂ annually, alongside significant reductions in pollutants like SO₂, NO_x, and CO [64]. These benefits extend to maritime logistics, where replacing diesel-based power systems with syngas from biomass could cut fossil-fuel-derived emissions. Moreover, comparative analyses reveal that biomass gasification performs better in terms of carbon footprint reduction than other renewable energy technologies, such as solar and wind, in scenarios where consistent energy supply is required [65]. Studies show that biomass gasification can generate off-grid electricity, reducing reliance on fossil fuels while supporting sustainable rural development [66]. Exergy sustainability assessments emphasize the role of biomass gasification in improving energy efficiency while minimizing environmental impact. Research shows that the exergy efficiency of gasification systems is closely linked to biomass composition, with higher carbon and hydrogen content improving efficiency [67].

Lifecycle assessments (LCAs) further validate the environmental benefits of biomass gasification in maritime logistics. The functional unit typically used in these assessments is “1 kWh of energy produced”, which can be either electricity or heat, depending on the specific energy output of the biomass gasification system. This allows for a consistent comparison of the environmental impacts of biomass gasification against other energy sources, such as diesel engines used in ships and port machinery. The boundary conditions of the LCA for biomass gasification are typically defined using a cradle-to-grave approach. This includes the entire lifecycle—from feedstock acquisition, through the gasification process, energy production, and, finally, the management of by-products like ash. For example, the emissions from biomass gasification systems can be as low as 7–15 g CO₂-e/kWh, significantly lower than those of diesel engines commonly used in ships and port machinery [68]. Furthermore, it has been demonstrated that integrating gasification with other renewable technologies in hybrid energy systems can improve the sustainability and resilience of energy supply chains for remote maritime operations [69]. A comparative study on steam and oxygen-fed biomass gasification found that steam-based gasification is the most environmentally sustainable, achieving higher energy efficiency and lower CO₂ emissions [70]. Studies on integrating biomass gasification with solid oxide fuel cells have also shown promising efficiency gains and reduced emissions compared to conventional combustion-based power generation.

Another key advantage of biomass gasification lies in its ability to repurpose organic waste, addressing waste management issues common in maritime settings. This technology converts waste into energy-rich syngas while also producing biochar as a valuable by-product for carbon sequestration and soil enhancement. Studies demonstrate that using municipal solid waste and biomass blends in gasification systems reduces landfill contributions and methane emissions while maximizing energy recovery [16]. For maritime logistics, this translates into opportunities to process shipboard waste or port-generated organic residues, closing the loop in waste-to-energy practices [71]. Research indicates that using municipal solid waste blended with biomass can optimize energy recovery while significantly reducing landfill waste and methane emissions [16]. This aligns with circular economy principles by integrating waste-to-energy solutions in port operations [72].

In summary, biomass gasification in ports can significantly contribute to environmental sustainability by lowering GHG emissions and addressing waste management issues. When paired with careful feedstock selection and process optimization, its environmental benefits are amplified, making it an important component of sustainable port energy systems.

5.2. Economic Feasibility

Biomass gasification has a strong economic potential in maritime logistics by offering a cost-effective alternative to traditional fossil fuels. The technology provides financial incentives for adoption in ports and shipping operations through efficient use of resources, cost savings, and integration with waste management systems.

Techno-economic analyses show that biomass gasification systems can achieve favorable financial metrics, including positive net present value (NPV) and competitive internal rates of return (IRR). For example, a 10 MW biomass gasification plant in Malaysia reported an NPV of 19.68 million Malaysian ringgits (MYR), an IRR of 11.90%, and a payback period (PBP) of just over six years under favorable financing conditions [40]. These metrics are further improved with the availability of carbon credits, highlighting the financial viability of gasification systems in markets with strong decarbonization incentives. Similarly, studies have shown that gasification-based systems in rural and remote areas outperform diesel generators in terms of operating costs and lifecycle economic performance, providing support for their implementation in isolated ports and maritime hubs [69].

Waste-to-energy systems that use biomass gasification increase economic feasibility by offsetting the costs associated with waste disposal. Ports and marine operations often generate significant organic waste such as food, packaging, and biological residues that can be used as feedstock. By converting waste to energy, these systems reduce landfill costs and generate additional revenue streams. For example, lifecycle cost studies highlight that the use of waste feedstocks improves overall economic performance by reducing the costs of raw material procurement and creating marketable by-products such as biochar and syngas [71].

The scalability of gasification systems makes them more economically attractive. Modular gasification plants can be designed to meet the energy needs of various marine applications, from powering port equipment to providing electricity to ships moored in ports. A study analyzing combined cooling, heating, and power systems from biomass gasification showed that scaling these systems optimally reduces capital costs per unit of energy while maximizing economic returns [73]. Furthermore, hybrid setups that combine gasification with renewable energy sources like solar or wind can help to stabilize costs and enhance system efficiency [74].

Sensitivity analyses of biomass gasification projects highlight the importance of policy incentives and market conditions. Economic performance improves significantly in regions with strong subsidies, renewable energy incentives, or carbon credit markets. For example, a study of biomass gasification in Italy found that incentive mechanisms and feedstock costs had a major influence on profitability, with smaller-scale systems showing particular resilience to local markets [75].

Challenges remain in terms of high initial capital costs and feedstock price volatility. However, financial models show that long-term savings from lower operating costs and emissions-related penalties offset these barriers. By leveraging innovative financing mechanisms such as public–private partnerships, port authorities and maritime operators can mitigate upfront costs and realize economic benefits more rapidly [68].

Overall, the economic viability of biomass gasification in maritime logistics is well supported by strong financial metrics, cost-saving prospects, and scalability to a variety of sizes and applications. This technology has the potential to generate considerable economic returns while also contributing to sustainability goals by leveraging waste-to-energy benefits and policy-driven incentives.

5.3. Social Implications

Biomass gasification in maritime logistics has significant societal implications that go beyond environmental and economic dimensions. One important aspect is its potential to improve public health outcomes, particularly in coastal and port communities where air pollution from traditional shipping fuels has historically been harmful [76]. Globally, shipping-sourced emissions were projected to cause approximately 265,000 premature deaths in 2020, highlighting the urgent need for emission control efforts [77]. Implementing biomass gasification and other clean energy technologies in maritime logistics could help mitigate these health risks and improve air quality in coastal and port communities, contributing to better public health outcomes and quality of life.

Local engagement and community involvement are key factors in increasing the uptake of sustainable energy technologies and creating an enabling environment for their diffusion [78,79]. Therefore, the adoption of biomass gasification technology requires collaboration among a variety of stakeholders, including local governments, industry leaders, and community groups. Such cooperation is essential for addressing public concerns about safety and environmental impacts, as well as ensuring transparent decision-making processes [80]. Initiatives aimed at public engagement and education are also vital to building trust and acceptance of this technology, which can help to mitigate fears related to industrial operations and their potential social impacts.

Furthermore, the shift towards biomass gasification in maritime logistics necessitates a skilled workforce, which opens up numerous opportunities for skill enhancement and job growth. This is especially important for technical and engineering roles linked to the design, operation, and maintenance of gasification facilities. The International Renewable Energy Agency (IRENA) [81] points out that the renewable energy sector—encompassing bioenergy technologies like gasification—has the potential to create millions of jobs globally, many of which demand technical skills and specialized training. In the same vein, the U.S. Department of Energy [82] stresses the vital importance of workforce development in progressing bioenergy technologies, highlighting that focused education and vocational training initiatives are crucial for equipping workers for significant roles in a sustainable energy economy.

The adoption of biomass gasification in maritime logistics also has significant implications for social and gender equity. Biomass gasification mainly relies on agricultural residues and other organic materials, which are plentiful in rural regions. This creates new economic opportunities for rural communities by integrating them into the global renewable energy supply chain, thus improving education, healthcare, and overall quality of life [83]. Moreover, women, who often play a central role in biomass collection and management in many developing countries, stand to benefit significantly from improved access to clean energy and economic opportunities [84]. For instance, in rural areas, women are frequently responsible for gathering biomass for household energy needs, and their involvement in biomass gasification projects can empower them economically and socially. Furthermore, the renewable energy sector offers opportunities for women as entrepreneurs, facilitators, designers, and innovators throughout the energy supply chain [85]. Indeed, empowering women in the energy sector can contribute to sustainable development and the achievement of multiple Sustainable Development Goals [86].

Ultimately, biomass gasification promotes environmental and social accountability in maritime logistics. By synchronizing operations with global sustainability goals, the industry will not only boost its environmental performance but also strengthen its reputation among consumers and communities that prioritize social consciousness. This alignment could lead to greater community support and inspire additional advancements in sustainable practices within maritime operations [87,88].

The sustainability implications of biomass gasification in ports, encompassing environmental, economic, and social dimensions, are summarized in

Table 1. Sustainability Assessment of Biomass Gasification in Ports.

Dimension	Key Implications	Refs.
Environmental	− Reduces emissions and pollution, supporting cleaner air and lower carbon footprints.	[16,18,64,65,68,71]
	− Repurposes organic waste, reducing landfill contributions and methane emissions.
	− Integration with other renewable technologies enhances energy resilience and sustainability. − Potential environmental trade-offs include land use changes and biodiversity loss if purpose-grown biomass is used.
	− Promotes responsible resource use.
Economic	− Provides cost-effective energy solutions compared to fossil fuels.	[40,68,69,71,73]
	− Generates revenue through waste management and sale of by-products like biochar and syngas.
	− Demonstrates strong financial metrics (e.g., positive NPV, competitive IRR).
	− Demonstrates scalability and adaptability for various energy needs.
	− Benefits from policy incentives, subsidies, and carbon credit opportunities.
Social	− Improves public health by reducing air pollution in port and coastal communities.	[76,78,79,83,84]
	− Creates job opportunities and skill development in technical and engineering roles related to gasification facilities.
	− Strengthens rural economies by integrating local resources into energy systems.
	− Encourages community engagement and trust.
	− Promotes gender equity by empowering women in energy-related activities.

.

6. Key Energy Demands in Ports and Integration Opportunities of Biomass Gasification

Ports are among the most energy-intensive hubs, requiring substantial electricity for operations that support global trade and logistics. These operations include powering docked vessels, maintaining refrigerated storage, operating cargo-handling equipment, supporting lighting and administrative functions, and supplying fuels for maritime and land-based vehicles. Meeting these demands sustainably has become increasingly important as global regulations push for decarbonization in the maritime sector.

Onshore power supply, also known as cold ironing, is one of the largest energy needs in ports. Ships rely on electricity to support critical functions such as lighting, heating, cooling, and cargo operations while docked [89]. Traditionally, this energy has been generated using diesel engines that emit significant amounts of sulfur oxides (SO_x), nitrogen oxides (NO_x), and CO₂. The transition to port-supplied shore power, especially when derived from renewable technologies like biomass gasification, would significantly reduce emissions and promote cleaner port environments [90,91].

In addition to onshore power, ports handling perishable goods face high energy demands for refrigerated storage [92]. These facilities operate continuously to maintain temperature-sensitive cargo under the required temperature boundaries, especially in high-temperature or tropical regions. The substantial load these operations place on the grid infrastructure makes renewable energy integration critical [93]. Biomass gasification systems can support the pathway of converting organic waste into syngas, providing a sustainable energy source to power these refrigeration units while promoting waste reduction.

Ports also serve as fuel supply hubs for both maritime vessels and vehicles operating within and outside of the port. Traditionally, vessels rely on marine diesel or heavy fuel oil, both of which contribute significantly to GHG emissions [94]. Biomass gasification provides a pathway to produce intermedate feedstocks (the syngas) needed for production of biofuels like methanol and hydrogen. These renewable-based fuels can be used to power ships, providing a cleaner substitute for conventional fuels. For example, hydrogen is increasingly being considered as a viable marine fuel due to its zero-emission profile in fuel cells [95]. Likewise, methanol produced from biomass gasification has shown to be a viable solution for retrofitting existing ships, in line with the global push for cleaner transport solutions [96].

Cargo-handling equipment, including cranes and forklifts, also has a significant energy demand. Electrifying this equipment with power generated from biomass gasification can dramatically lower emissions while boosting energy efficiency [97]. Beyond electrification, these systems can also be retrofitted to run on biofuels such as hydrogen or methanol, thus enhancing the flexibility of biomass-sourced energy. Administrative buildings, communication systems, and lighting infrastructure further add to the energy requirements of ports. These systems need reliable and continuous power, making renewable energy integration an essential part of accomplishing sustainability objectives. Biomass gasification provides a robust solution, generating electricity and heat on-site to enhance energy security and lower the carbon footprint of these critical operations [98].

Table 2. Biomass Gasification Applications for Sustainable Energy Solutions in Ports.

Energy Demand in Ports	Integration Opportunities of Biomass Gasification	Refs.
Onshore Power Supply (Cold Ironing)	− Provides renewable energy for shore power, reducing emissions and promoting cleaner port environments.	[89,90,91]
Refrigerated Storage	− Supplies sustainable energy to power refrigeration units, reducing reliance on grid electricity and supporting continuous cooling needs.	[92,93]
Fuel Supply for Maritime and Land Vehicles	− Produces biofuels as cleaner substitutes for conventional fuels, supporting decarbonization.	[94,95,96]
Cargo-Handling Equipment	− Enables electrification or retrofitting with biofuels to reduce emissions and improve efficiency.	[97]
Administrative and Lighting Systems	− Generates on-site electricity and heat, enhancing energy security and reducing the carbon footprint of port operations.	[98]

summarizes key energy demands in ports and highlights the potential integration opportunities of biomass gasification to address these needs sustainably.

7. Policy and Regulatory Frameworks

The integration of biomass gasification in maritime logistics and port operations is significantly affected by the policy and regulatory frameworks at both global and regional scales. Governments and international organizations are essential in establishing incentives, standards, and compliance requirements that can either promote or hinder the adoption of sustainable energy technologies like biomass gasification. This section explores the primary policies, regulations, and incentives that impact the use of biomass gasification in ports, alongside their related challenges and opportunities.

7.1. Global Policies and International Agreements

IMO has been at the forefront of global efforts to reduce GHG emissions from the maritime sector. The Initial GHG Strategy established by the IMO in 2018 targets a reduction of at least 50% in total annual GHG emissions from international shipping by 2050, relative to 2008 figures, placing a strong focus on decarbonization and the use of alternative fuels such as biofuels and hydrogen produced from renewable sources like biomass gasification [99]. In addition, the IMO’s Energy Efficiency Design Index (EEDI) and Ship Energy Efficiency Management Plan (SEEMP) promote the implementation of energy-efficient technologies and the utilization of renewable energy sources in maritime operations, which may incorporate biomass gasification for generating onshore power and producing fuel [100].

Initiatives such as the IMO 2020 Sulphur Cap also mandate significant reductions in sulfur oxide (SO_x) emissions from ships and create demand for alternative energy solutions such as biomass gasification. The IMO 2020 regulations, which came into force on the 1st of January 2020, limit the sulfur content of marine fuels to 0.5% globally, down from the previous limit of 3.5% [101]. This has led to increased interest in low-sulfur fuels such as biofuels and hydrogen, which can be produced through biomass gasification.

The Paris Agreement [102], a global initiative under the United Nations Framework Convention on Climate Change (UNFCCC), further highlights the critical importance of decreasing carbon emissions in all sectors, including maritime logistics. Signatory countries must submit Nationally Determined Contributions (NDCs) every five years, outlining their individual targets to address climate change. Biomass gasification aligns well with this goal, providing a viable solution to lower greenhouse gas emissions in ports and shipping activities, advancing towards a more sustainable and environmentally friendly future.

7.2. Regional and National Policies

In Europe, the European Green Deal and the Fit for 55 package provide a holistic policy framework to cut GHG emissions by 55% by 2030 and be climate neutral by 2050. This includes specific action for advancing the uptake of renewables in the maritime sector. Among them, the Renewable Energy Directive (RED II) includes binding targets on the use of renewable energy in the transport sector, covering renewable biofuels and synthetic fuels generated via gasification of biomass [103]. In addition, the European Union Emissions Trading System (EU ETS), with the inclusion of maritime emissions in 2024, establishes a financial mechanism to incentivize the adoption of low-carbon technologies like biomass gasification to avoid carbon costs [104]. These policies together highlight the EU’s commitment to decarbonizing the maritime sector and realize its climate goals.

In the United States, the Inflation Reduction Act (IRA) of 2022 provides significant incentives for renewable energy projects, with tax credits for bioenergy and carbon capture technologies [105]. This would allow biomass gasification projects to be more commercially attractive for ports and maritime operators. Besides, the Maritime Administration has established programs to encourage the adoption of alternative fuels and renewable energy for ports, such as the Port Infrastructure Development Program (PIDP), which offers grants to projects that enhance energy efficiency and decrease emissions [106].

Asian countries, like China and Japan, have also introduced policies to promote renewable energy in the maritime sector. As an example, China’s 14th Five-Year Plan [107] sets targets to improve the uptake of renewable energy in transport, which may provide opportunities for biomass gasification to play a role. Likewise, Japan’s Green Growth Strategy [108] aims for carbon neutrality by 2050 and includes plans to promote the use of biofuels and hydrogen in shipping, among others, through projects such as BIOSHIP to explore the potential of biomass to produce marine fuels.

7.3. Incentives and Financial Mechanisms

Financial incentives are crucial in speeding up the implementation of biomass gasification in the maritime industry. Studies show that subsidies significantly impact investment decisions, pricing strategies, and profitability for ports and shipping companies [109,110]. Optimal subsidy structures can maximize emission reduction efficiency per monetary unit, with a focus on balancing facility construction and operational support [111]. Cost–benefit analyses reveal that appropriate subsidies can accelerate investment payback periods for both ports and ships [112]. However, subsidy effectiveness varies depending on factors such as investment costs, low-carbon market preferences, and cost-sharing ratios between stakeholders [109].

Carbon credit markets such as the Clean Development Mechanism (CDM) under the Kyoto Protocol and voluntary carbon markets offer ports and maritime operators a chance to earn money while cutting emissions through biomass gasification projects [113]. Additionally, green bonds and sustainability-linked loans are becoming more popular as financial tools to fund renewable energy projects, including biomass gasification, in the maritime sector [114].

Public–private partnerships serve as another essential financial tool for promoting biomass gasification initiatives within this industry. By collaborating with private enterprises, ports can share the high upfront costs and technical uncertainties linked to renewable energy projects, making biomass gasification more economically feasible [115]. The Port of Rotterdam in the Netherlands, for example, has partnered with leading companies such as Shell, BP, and Neste to develop renewable energy projects aligned with its target of becoming a carbon-neutral port by 2050 [116]. The ports of Long Beach and Los Angeles have also collaborated with industry stakeholders to adopt renewable energy projects, as outlined in their Clean Air Action Plan [117].

7.4. Compliance and Standards

The adherence to environmental regulations is a major driving force behind the implementation of biomass gasification across the maritime logistics chain. Emission Control Areas (ECAs), established under the IMO’s MARPOL Annex VI, impose strict reductions in SOx and NOx emissions from vessels operating in regions like the Baltic Sea, North Sea, and North American coasts [118,119]. Biomass gasification enables compliance with such regulations by providing low-emission energy solutions for key components of maritime logistics.

In addition to international regulations, ports must also comply with national and local environmental standards, which often impose stricter requirements on emissions and air quality. For example, the California Air Resources Board has implemented strict air quality standards for ports and shipping operations, including the At-Berth Regulation, which requires ships to reduce emissions while docked [120]. Biomass gasification can support adherence to these regulations by providing renewable energy for critical operations throughout the maritime logistics chain.

The policy and regulatory frameworks influencing the adoption of biomass gasification in maritime logistics and port operations are summarized in

Table 3. Policy and Regulatory Framework for Biomass Gasification in Maritime Logistics and Port Operations.

Aspect	Key Policies/Initiatives	Implications for Biomass Gasification	Refs.
Global Policies	− IMO’s Initial GHG Strategy (50% reduction in shipping emissions by 2050).	− Promotes decarbonization and use of alternative fuels like biofuels and hydrogen from biomass gasification.	[99]
	− IMO’s Energy Efficiency Design Index (EEDI) and Ship Energy Efficiency Management Plan (SEEMP).	− Encourages energy-efficient technologies and renewable energy integration, including biomass gasification.	[100]
	− IMO 2020 Sulphur Cap (0.5% sulfur limit in marine fuels).	− Increases demand for low-sulfur fuels like biofuels and hydrogen produced via biomass gasification.	[101]
	− Paris Agreement and Nationally Determined Contributions (NDCs).	− Aligns with global decarbonization goals, supporting biomass gasification as a low-carbon energy solution.	[102]
Regional/National Policies	− European Green Deal and Fit for 55 package (55% GHG reduction by 2030, climate neutrality by 2050).	− Includes binding targets for renewable energy in transport, supporting biomass gasification for biofuels.	[103]
	− EU Emissions Trading System (EU ETS) inclusion of maritime emissions (2024).	− Incentivizes low-carbon technologies like biomass gasification to avoid carbon costs.	[104]
	− U.S. Inflation Reduction Act (IRA) of 2022 (tax credits for bioenergy and carbon capture).	− Makes biomass gasification projects more economically viable for ports and maritime operators.	[105]
	− U.S. Port Infrastructure Development Program (PIDP).	− Provides grants for energy efficiency and emission reduction projects, including biomass gasification.	[106]
	− China’s 14th Five-Year Plan (renewable energy targets for transport).	− Creates opportunities for biomass gasification in maritime logistics.	[107]
	− Japan’s Green Growth Strategy (carbon neutrality by 2050, BIOSHIP project).	− Promotes biofuels and hydrogen in shipping, including biomass-derived fuels.	[108]
Incentives/Financial Mechanisms	− Subsidies for renewable energy projects.	− Accelerates investment in biomass gasification by reducing payback periods and improving profitability.	[109,110]
	− Carbon credit markets (e.g., Clean Development Mechanism).	− Provides revenue streams for emission reductions achieved through biomass gasification.	[113]
	− Green bonds and sustainability-linked loans.	− Funds renewable energy projects, including biomass gasification, in the maritime sector.	[114]
	− Public–private partnerships (e.g., Port of Rotterdam, ports of Long Beach and Los Angeles).	− Shares costs and risks, making biomass gasification more feasible for ports and maritime operators.	[115,116,117]
Compliance/Standards	− IMO’s MARPOL Annex VI and Emission Control Areas (ECAs).	− Requires low-emission energy solutions, which biomass gasification can provide.	[118,119]
	− California Air Resources Board’s At-Berth Regulation.	− Mandates emission reductions while docked, supporting the use of renewable energy like biomass gasification.	[120]

, highlighting the global, regional, and financial mechanisms that support its integration.

8. Projects and Case Studies in Maritime Biomass Gasification

While biomass gasification is a well-studied technology for energy vectors’ generation and sustainability, its application in maritime logistics is less developed than in other industrial sectors. Nonetheless, there are promising initiatives and exploratory projects in specific regions that demonstrate its possibility for addressing emissions reduction and renewable energy targets in the shipping and port sectors.

An ambitious initiative to develop the world’s first biomass-fueled ship was started in May 2024 by Japanese companies NYK Line, NYK Bulk & Projects Carriers, TSUNEISHI SHIPBUILDING, along with the British renewable energy firm Drax Group. By using syngas derived from biomass gasification, this vessel, called BIOSHIP, seeks to decarbonize the transportation of biomass pellets to Japan. According to early estimates, the ship could establish a standard for the integration of renewable energy in marine logistics by reducing carbon emissions by 22% [121].

In China, advances have been made by combining biomass gasification and water electrolysis to produce green methanol, a maritime fuel with 95% lower greenhouse gas emissions than heavy fuel oil. This novel strategy is consistent with the International Maritime Organization’s (IMO) sustainability goals, highlighting biomass gasification as a critical enabler of sustainable shipping strategies [96].

Sweden has also explored biomass gasification through a techno-economic assessment of methanol synthesis from sawmill residues. In order to optimize plant locations and sizes and reduce costs, this study examined the full production chain, including feedstock availability and energy demands at ports. The findings highlight the potential of methanol as a sustainable substitute for fossil fuels, with sawmill scraps providing a plentiful supply for its production [122].

In California, research has evaluated the feasibility of renewable methanol production through biomass gasification using proton exchange membrane electrolysis. This approach supports the use of renewable fuels to decarbonize maritime operations, contributing to global clean energy goals [123]. Additionally, the BioSFerA project, supported by the European Union’s Horizon 2020 research and innovation program, successfully developed syngas-derived hydrotreated triacylglycerides as biofuels tailored for aviation and maritime sectors. These biofuels provide a sustainable and scalable alternative to conventional fossil fuels, further demonstrating the versatility of biomass gasification technologies [124].

Compact Syngas Solutions (CSS) in the UK is advancing biomass-derived hydrogen technology by developing a 50 kW hydrogen auxiliary engine for cargo vessels. Using advanced gasification methods, the system converts waste materials into hydrogen gas, electricity, and heat. Trials are scheduled for March 2025 on a K-class cargo vessel, supporting the UK’s Net Zero 2050 goals through low-carbon hydrogen innovations [125]. A broader review of biofuels and electrofuels by Saadeldin et al. [126] also highlights the potential of green fuels produced from biomass and syngas in addressing the energy and sustainability challenges of the maritime sector.

The projects and case studies discussed in this section, and summarized in

Table 4. Key Projects and Case Studies in Maritime Biomass Gasification.

Project/Initiative	Description	Key Outcomes/Contributions	Ref.
BIOSHIP Project (Japan)	− Development of the world’s first biomass-fueled ship by NYK Line, TSUNEISHI SHIPBUILDING, and Drax Group.	− Aims to reduce carbon emissions by 22% and set a standard for renewable energy in marine logistics.	[121]
Green Methanol Production (China)	− Integration of biomass gasification and water electrolysis to produce green methanol.	− Reduces greenhouse gas emissions by 95% compared to heavy fuel oil, aligning with IMO goals.	[96]
Methanol from Sawmill Residues (Sweden)	− Techno-economic assessment of methanol synthesis from sawmill residues.	− Highlights methanol as a sustainable fuel alternative, leveraging abundant sawmill waste.	[122]
Renewable Methanol Production (California)	− Feasibility study of renewable methanol production using biomass gasification and proton exchange membrane electrolysis.	− Supports decarbonization of maritime operations and contributes to global clean energy goals.	[123]
BioSFerA Project (EU Horizon 2020)	− Development of syngas-derived hydrotreated triacylglycerides as biofuels for aviation and maritime sectors.	− Provides scalable and sustainable alternatives to conventional fossil fuels.	[124]
Compact Syngas Solutions (CSS) (UK)	− Development of a 50 kW hydrogen auxiliary engine for cargo vessels using biomass gasification.	− Converts waste materials into hydrogen, electricity, and heat, supporting UK’s Net Zero 2050 goals.	[125]

, highlight the revolutionary potential of biomass gasification in the maritime sector as a suitable technological alternative integrating solid waste management and green energy vectors’ production. These initiatives, which use a variety of resources and creative approaches, pave the way for the integration of renewable energy solutions into global shipping, greatly contributing to decarbonization and sustainability efforts.

9. Risk Assessment and Mitigation Strategies

Incorporating biomass gasification into port and shipping operations has considerable potential to improve sustainability in maritime logistics. Nevertheless, this transition is not free of risks. Conducting a thorough risk assessment and developing a mitigation strategy are crucial for the effective implementation and enduring success of biomass gasification systems. This section highlights the primary risks related to biomass gasification in maritime logistics and suggests strategic measures for mitigation.

9.1. Technical Risks

Technical risks pertain to the complexities associated with biomass gasification processes. One key challenge is feedstock variability, which requires flexible gasifier designs capable of handling different biomass types and qualities [127]. The availability of biomass feedstock itself presents another challenge, as fluctuations in supply can impact the stability and reliability of the gasification process. Factors such as seasonal variations, transportation delays, or interruptions in the biomass supply chain can lead to inconsistent feedstock quantities and quality, further complicating the operation. Although the focus of this study is on biomass waste produced in the port, addressing feedstock availability remains a critical concern. Variations in biomass waste generation within port environments can influence both the efficiency of gasification and the economic performance of biomass-to-energy systems [128,129]. Optimizing logistics and ensuring a stable waste stream are key considerations for minimizing the impact of feedstock variability on the overall process.

Additionally, the presence of contaminants in the produced syngas poses further challenges. Tar formation is particularly problematic, as it can lead to fouling and plugging of plant pipelines [127]. Other impurities, such as H₂S, HCl, and alkali metals, can accelerate equipment’s corrosion and degradation, requiring effective gas-cleaning technologies [46,47].

Comprehensive feasibility assessments and pilot experiments can help mitigate these risks by determining the most suitable gasification technologies for port operations [46]. The implementation of sophisticated monitoring and control systems can also enhance process stability and efficiency. Furthermore, collaborating with technology providers and research institutions allows for the utilization of their expertise to improve gasification performance [18].

9.2. Financial and Market Risks

Biomass gasification projects face significant financial hurdles, including high initial capital investments (e.g., gasification reactors, syngas purification systems) and operational costs (e.g., maintenance of complex onboard systems). These challenges are particularly acute for ports and maritime operators with limited funding. While feedstock costs are mitigated by using low-cost or negative-cost waste materials, financial risks persist due to uncertainties in government policies, limited involvement of financial institutions, and short-term orientation of financial instruments [130]. Moreover, the return on investment may take several years to realize, with one study reporting a payback period of close to 20 years [131]. Market risks are also important, as changes in energy prices, competition with traditional fossil fuel technologies, and uncertainties in biomass feedstock supply and demand can affect the feasibility of projects. Fluctuations in biomass availability due to seasonal changes and competition from other industries may disrupt supply chains, impacting economic results [132].

To address financial risks, ports need to take a wide range of risk mitigation strategies to ensure economic feasibility and attract investment. For instance, subsidies, grants, and tax incentives can be sought to alleviate initial capital expenditure. Collaboration with private investors and stakeholders via public–private partnerships may offer extra funding resources and risk-sharing options. Furthermore, it would be beneficial to demonstrate long-term savings and potential returns for attracting investors by undertaking a detailed cost–benefit analysis and financial modeling. Such risk mitigation strategies must incorporate enabling insurance mechanisms against economic losses resulting from technical failures or adverse price variability [133]. Gradual and phased deployment strategies can further help mitigate risks and costs by spreading the investment across multiple budget cycles over time, allowing for incremental investments based on market demand and data-based strategy adjustments. In addition, focusing on developing a sound business model is crucial to ensure financial sustainability. Business models significantly influence the economic and environmental performance of biomass gasification projects in ports, with those utilizing locally available waste materials offering greater positive externalities and lower social costs compared to those using biomass waste that is privately owned (proprietary biomass waste) [134]. To further mitigate market risks, ports should adopt diversified revenue streams such as selling surplus energy to the grid, offering carbon credits, and partnering with industries requiring sustainable energy solutions. Establishing long-term supply contracts with biomass suppliers and securing off-take agreements with energy buyers can help stabilize revenue and reduce financial uncertainties [40].

9.3. Environmental Risks

Despite its advantages, biomass gasification is not without environmental risks. The process has been associated with air and water pollution, particularly when by-products such as tar and ash are not effectively managed. Gasification plants, similar to mass-burn incinerators, may contribute to air pollution through emissions of particulate matter and volatile organic compounds [135,136]. Additionally, improper disposal of solid residues and wastewater can lead to soil and water contamination [137]. An example of this is the gasification of rice husks for small-scale power generation in Cambodia, where untreated wastewater containing high concentrations of harmful contaminants is discharged into local environments, posing risks to aquatic ecosystems [138].

According to Refs. [20,74,139], another concern is the potential for land use changes and deforestation when biomass is sourced from purpose-grown energy crops. Studies indicate that large-scale biomass production can lead to deforestation, habitat loss, and biodiversity decline, particularly in tropical regions [139]. For example, in Indonesia, the rapid growth of oil palm, plywood, and pulp industries has contributed significantly to forest loss [140]. Similarly, in South Korea, reliance on imported wood pellets from Indonesia for biomass energy has been linked to deforestation, raising concerns about biodiversity loss and ecosystem disruption [141]. While some positive effects on biodiversity have been reported at the field scale, impacts largely depend on management practices, plantation characteristics, and initial land use. Second-generation bioenergy crops tend to have fewer negative impacts than first-generation crops, especially in temperate regions. To ensure sustainable biomass production, biodiversity conservation should be integrated into strategic landscape planning and risk assessment measures [139,142]. Furthermore, more accurate metrics for biodiversity assessment and environmental characterization are needed to better quantify the effects of land use changes towards bioenergy crop cultivation [143].

Occupational health and safety risks also present a significant concern in biomass gasification plants, where workers may be exposed to hazardous chemicals and combustion by-products [144]. Studies conducted at biomass gasification installations in Uganda—Muzizi Tea Estate, Kyambogo University, and Makerere University—have highlighted significant toxic hazards, particularly from pollutants such as CO and particulate matter. The concentration of CO at these installations was found to exceed the threshold limit value of 50 ppm for a normal working day, with average CO concentrations of 126 ppm, 85 ppm, and 64 ppm at Kyambogo, Muzizi, and Makerere plants, respectively. Similarly, PM concentrations were recorded at 540 μg/m³, 200 μg/m³, and 64 μg/m³, respectively [145]. The startup process is critical for safety, with heating temperature identified as a key factor [146]. Pre-combustion risks, including bioaerosols and biogenic organics, require further investigation [144]. To mitigate these risks, proper safety protocols, emission controls, and advanced gas cleaning systems are necessary. Preventive measures include adjusting biomass granulometry, worker training, good ventilation, and reliable equipment [146,147]. Additionally, stakeholders should emphasize existing international health, safety, and environmental standards to promote safe commercialization of biomass gasification technology [145].

Overall, the environmental challenges could undermine the sustainability goals of ports and may result in violations of regulations. Ports can implement cutting-edge gas-cleaning technologies for effective contaminant removal [148]. Moreover, establishing strict environmental monitoring and control protocols, such as lifecycle assessments and impact evaluations, can help ensure adherence to regulations and reduce adverse effects [13,74]. Using sustainable biomass sources, like agricultural leftovers and certified forestry products, can also lower the ecological impact of the gasification process [149]. Furthermore, investing in waste management strategies, including the reuse and recycling of by-products such as biochar and ash, can improve the sustainability of biomass gasification at ports [150].

9.4. Social Risks

Social risks linked to biomass gasification initiatives include issues regarding land use, the displacement of local populations, and public attitudes toward emissions and environmental impacts. Communities may resist such projects due to concerns about health hazards, loss of agricultural land, and disruptions to their traditional livelihoods [151]. Misinformation and a lack of understanding about the advantages and safety of biomass gasification can intensify this resistance [80]. Furthermore, social inequalities may arise if the economic gains from these projects are not shared fairly, resulting in tensions between various stakeholders and local communities [152].

To reduce social risks and promote acceptance, comprehensive stakeholder engagement programs are essential. These should involve local communities from the planning stage to operations, providing transparent information about environmental and economic benefits [153]. Furthermore, fair compensation for land acquisition and ensuring job opportunities for affected communities can increase social acceptance [154]. Developing educational initiatives and community outreach programs to raise awareness about sustainability aspects are also important. Trust is a key factor in high-income countries, while education and women’s living conditions are significant in low–middle-income countries. Tailoring strategies to local contexts is key to understanding acceptance dynamics [155]. By addressing these factors, bioenergy companies can effectively manage social risks and create mutually beneficial outcomes for all stakeholders [154].

9.5. Regulatory and Compliance Risks

Regulatory and compliance risks pose serious challenges in biomass gasification initiatives, as these projects are required to meet rigorous environmental, safety, and operational standards established by national and global authorities. Ports involved in biomass gasification must adhere to regulations concerning air emissions, waste management, and worker safety, which can increase both operational complexity and expenses. Non-compliance with these regulatory standards may lead to legal issues, project delays, and damage to reputation. Furthermore, managing the intricate and dynamic regulatory landscape can be difficult, as new regulations and stricter environmental standards are introduced over time [156,157,158].

To minimize regulatory and compliance risks in biomass gasification, ports should adopt proactive measures. Engaging with regulatory bodies early in project planning is crucial for understanding compliance requirements [159]. Regular audits and environmental impact assessments can also help identify areas for improvement [160]. Investing in advanced monitoring technologies can provide real-time data on emissions and other regulatory factors [18]. Moreover, ports should establish comprehensive compliance management systems with training programs to educate staff on regulatory responsibilities [160]. Collaboration with industry stakeholders and participation in policy development initiatives can further help ports anticipate regulatory changes [159]. Additionally, considering social and environmental aspects when designing biomass gasification facilities is essential for sustainable implementation [20]. These proactive measures can help ports navigate the complex regulatory landscape surrounding biomass gasification and ensure long-term compliance.

Figure 2 illustrates the advantages and disadvantages of biomass gasification in ports and maritime logistics, highlighting its technical, environmental, economic, and social impacts.

10. Future Prospects and Research Directions

Despite notable technical advancements in biomass gasification, an in-depth analysis of the literature reveals several gaps that must be addressed before these innovations can be fully realized in sustainability-oriented port management and maritime logistics. In many cases, studies have focused on laboratory-scale improvements without sufficiently exploring their implications for large-scale deployment or policy formulation, underscoring the need for international collaboration and knowledge sharing. A more integrated approach that balances technological innovation with practical, economic, and regulatory considerations is therefore essential.

One key research frontier is the development of next-generation catalysts and feedstock pre-treatment technologies. Laboratory investigations into nanocatalysts, bifunctional catalysts, and biomimetic catalysts have shown promising improvements in syngas quality and reductions in tar production and emissions [161,162,163,164]. However, there remains a critical need to evaluate these technologies under industrial conditions. Similarly, advanced pre-treatment methods—such as torrefaction, pyrolysis, and emerging techniques like microwave-assisted pyrolysis—are designed to optimize biomass properties [165,166]. Yet, the literature often overlooks detailed assessments of scalability and cost-effectiveness. Future studies should rigorously assess how these innovations can transition from controlled experiments to robust, economically viable systems in port environments.

Another area demanding further exploration is the use of novel biomass feedstocks. Conventional sources such as wood chips and agricultural residues have well-documented performance profiles, but alternatives like algae, marine macroalgae, and organic waste from aquaculture and fisheries offer unique advantages [167,168,169]. These alternatives could enhance energy yields and contribute to carbon sequestration and waste reduction. Nevertheless, there is a notable absence of comprehensive lifecycle analyses and comparative studies that critically evaluate the sustainability and operational impacts of these novel feedstocks relative to traditional options.

Integration with decentralized and modular gasification systems, along with the incorporation of digital technologies, also represents a promising avenue for research. Early efforts in deploying AI-driven optimization, digital twins, and edge computing for process monitoring and control indicate that these tools could significantly enhance operational efficiency [170,171,172,173,174,175]. Yet, the current body of work does not adequately address the challenges of integrating such systems within existing port infrastructures or the potential economic implications of widespread adoption. Future research should bridge this gap by developing case studies and pilot projects that assess the real-world performance and costs and benefits of these innovations.

The current role of biomass in European ports provides valuable lessons and avenues for further research. Ports such as Moerdijk, Rotterdam, Groningen, and North Sea Port have integrated biomass-based solutions, including bioenergy plants that produce heat and electricity, poultry manure conversion to power, and the production of bioLNG from industrial waste. Additionally, waste incineration plants in Rotterdam and Moerdijk partly use biomass, contributing to CO₂ reduction [176]. Despite these advancements, large-scale sustainability concerns persist, particularly regarding feedstock sourcing and lifecycle emissions. Future research should focus on ensuring sustainable biomass supply chains and improving certification frameworks to guarantee environmentally responsible biomass use in ports.

Energy storage solutions further underscore the multifaceted challenges of integrating biomass gasification into maritime logistics. While coupling gasification with advanced storage technologies, such as proton exchange membrane fuel cells, vanadium redox flow batteries, and compressed air energy storage, holds promise for stabilizing energy supply [177,178,179], there remains a dearth of studies that link these technical solutions with commercial feasibility. Additionally, the conversion of syngas into synthetic fuels like methanol and ammonia represents a promising avenue for long-term energy storage [180,181]. This is particularly critical given the intermittency of renewable energy sources and the financial risks associated with scaling up these systems.

Beyond these technical dimensions, broader systemic challenges also merit focused investigation. For instance, global collaboration and knowledge sharing are essential to accelerate the adoption of biomass gasification in maritime contexts. Future research should emphasize establishing international partnerships, along with the development of standardized frameworks, open-access databases, and best practice guidelines that enable consistent performance assessment and sustainability evaluations across diverse port settings [78]. Equally important is the exploration of policy and market incentives that can drive the transition from experimental systems to large-scale applications. Investigating the effectiveness of carbon pricing strategies, green finance options, and public–private collaborations will be crucial to mitigate the financial barriers associated with gasification initiatives, while the creation of certification schemes for sustainable biomass sourcing and gasification practices can bolster market confidence and attract further investment [130,182,183].

Moreover, as biomass gasification projects continue to expand, comprehensive social and environmental impact assessments become indispensable. Future studies should develop robust methodologies for lifecycle analysis and frameworks for evaluating the social impacts of these projects, ensuring that the long-term benefits outweigh potential risks and that local communities are actively engaged in the transition process [74]. Finally, addressing the challenges of scaling up and commercialization remains vital. Although small-scale and modular gasification systems have demonstrated considerable promise, large-scale deployment in port environments requires extensive economic feasibility assessments and pilot projects that validate commercial viability. Establishing standardized protocols and best practices for the design, operation, and maintenance of gasification systems will be key to overcoming these hurdles and ensuring widespread implementation [184].

In summary, while emerging technologies and innovative research directions in biomass gasification offer exciting prospects for enhancing sustainability in port and maritime logistics, significant challenges remain. Future research must extend beyond technical demonstrations to critically evaluate scalability, economic viability, policy integration, and social and environmental impacts, while fostering global collaboration and knowledge sharing. This comprehensive approach will provide a clearer roadmap for transitioning biomass gasification from laboratory innovation to practical, real-world application.

11. Conclusions

Integrating biomass gasification into port and shipping activities holds significant promise for improving sustainability in maritime logistics. This technology effectively decreases GHG emissions, streamlines waste management, and enhances energy efficiency within port environments. Nevertheless, its successful implementation hinges on resolving technical, economic, and social complexities while aligning with evolving policy landscapes.

The findings of this study emphasize the necessity of comprehensive risk assessments and mitigation strategies to ensure the enduring success of biomass gasification projects. Major challenges involve the need for technological improvements to enhance efficiency and scalability, as well as the establishment of flexible and adaptive systems capable of handling variable biomass feedstocks. Moreover, financial incentives—such as tax credits, subsidies, and carbon credit schemes—are essential to offset high initial capital costs and to drive broader industry adoption.

Equally critical are the policy and regulatory frameworks that create a supportive environment for renewable energy innovations. Policymakers must develop and enforce rigorous standards and streamlined permitting processes that both protect environmental and public health interests and stimulate investment in sustainable energy solutions. International agreements and regional initiatives, such as the European Green Deal, the U.S. Inflation Reduction Act, and the decarbonization targets promoted by the International Maritime Organization (IMO), offer robust foundations for this enabling environment. These frameworks not only de-risk investments but also provide clear, long-term policy signals that can catalyze industry-wide shifts toward renewable energy. Furthermore, collaborative efforts among governments, industry stakeholders, and local communities are essential to align technological advancements with societal needs and ensure that the transition to sustainable port operations is inclusive and economically beneficial.

Looking ahead, future research should bridge the gap between laboratory-scale advancements and practical, large-scale deployment in port environments by developing standardized frameworks for lifecycle and sustainability assessments that integrate technical, economic, environmental, and social dimensions. Moreover, advancing next-generation catalysts and innovative feedstock pre-treatment methods, such as torrefaction, pyrolysis, and microwave-assisted techniques, will be essential for enhancing syngas quality and reducing emissions. Decentralized, modular gasification systems tailored to specific port energy demands, coupled with digital technologies like AI-driven optimization and digital twins for real-time monitoring, will also improve scalability and operational resilience. Additionally, investigating advanced energy storage solutions and evaluating policy incentives, such as carbon pricing and green finance, will be critical to overcome financial barriers and facilitate sustainable adoption. These efforts will support resilient maritime transition.

In conclusion, gasification offers a viable solution for managing biomass-derived waste and producing renewable energy, playing a crucial role in sustainable port management. By addressing key challenges through an integrated approach, this technology enables the maritime sector to minimize its environmental footprint, improve energy efficiency, and enhance economic viability. Effective implementation of biomass gasification can support the transition to greener port operations, fostering a more resilient and circular economy while aligning with global sustainability goals.