TECHNICAL PROGRAMME | Energy Fuels and Molecules – Future Pathways
Alternative Fuels - E fuels, Biofuels and SAF
Forum 15 | Technical Programme Hall 3
28
April
14:30
16:00
UTC+3
Alternative fuels such as e-fuels, biofuels and SAF are attracting attention as a sustainable energy source for the future. Efforts to improve the production efficiency of these alternative fuels and reduce their carbon intensity will be an important part of realising a lower carbon energy system. This forum will introduce economically rational production technologies that apply innovative and existing technologies, the contribution of low-carbon fuels to achieving net zero, and the status of preparations for fuel standards and certification for practical use. It will also discuss cooperation with local communities and stakeholders, and the building of mutually beneficial relationships.
The aviation sector is among the hard to decarbonise sectors due to its reliance on high-energy-density fuels and long technology turnover cycles. While alternative technologies such as hydrogen fuel and electrification remain in early stage, alternative drop-in fuels, especially Sustainable Aviation Fuels (SAFs) and Low-Carbon Aviation Fuels (LCAFs), offer a near- to mid-term solution for emissions reduction, requiring minimal changes to existing aircraft and fuelling infrastructure. However, these fuels continue to face economic and market barriers, including high production costs, limited supply, and inadequate policy support.
For instance, e-kerosene which is a power-to liquid (PtL) sustainable aviation fuel is currently 5 times more expensive than conventional kerosene fuel. If the carbon source of the synthetic PtL fuel is from negative emissions using Direct-Air Capture (DAC), this price gap increases further up to 6 times more expensive than the current price of conventional fuel. Although that the current price of the biomass-based SAF is just around 3 times, however there are resource availability limitation especially in the arid and semi-arid regions, which give rise to energy security issues when these feedstocks are imported from somewhere else. LCAF which is a fossil-based clean aviation fuel exhibits the smallest price difference due to the fact that its price is calculated based on adding a premium equal the abatement cost. However, LCAF only reduce 10% of the lifecycle emissions of the aviation fuel, unlike other SAFs which reach 50-70% reduction.
The Kingdom of Saudi Arabia (KSA) holds a strategic position in global aviation to serve as a connection hub between Europe, Asia, and Africa, while also managing a rapidly growing domestic and international air travel market. As part of KSA Vision 2030, the country aims to transform its aviation sector by tripling its capacity while maintaining environmental sustainability. A major milestone in this effort is the development of Red Sea Airport, which is set to become the first carbon-neutral airport in the region, with Fly Red Sea fuelled exclusively with SAF and LCAF. Despite these opportunities, the sector still relies almost entirely on conventional jet fuels with the absence of any policy incentives to support alternative fuels.
This research proposes a novel design of market-based mechanisms (MBMs) to accelerate the uptake of alternative drop-in fuels in KSA aviation sector. In addition, a novel agent-based model (ABM) was developed to simulate the diffusion pathways for these alternative drop-in fuels under different MBM scenarios in KSA air fleet. The study provides insights on the optimal intervention mixes to accelerate decarbonisation in KSA aviation sector.
Co-author/s:
Gbemi Oluleye, Assistant Professor, Centre for Environmental Policy, Imperial College London.
In the mission to address climate change and secure a sustainable future, biofuels emerge as a source of optimism. By significantly reducing greenhouse gas emissions, biofuels not only enhance air quality but also mitigate environmental degradation. They offer a pathway to energy independence, diminishing our reliance on depleting fossil fuel reserves. Embracing biofuels is more than an environmental choice; it's a stride towards economic resilience and sustainable development. Recently, the spotlight has turned to hydrocracking units in biofuel production, unveiling promising avenues for creating Hydrotreated Vegetable Oil (HVO) and Sustainable Aviation Fuel (SAF). These advancements underscore the transformative potential of biofuels in our journey towards a cleaner planet, reducing CO2 emissions from fossil feedstocks.
The hydrocracker unit, initially commissioned in 1991 and revamped in 2009 to optimize middle distillate production, mirrors evolving fuel market trends. This study explores the coprocessing of Used Cooking Oil (UCO), not containing palm oil, within a single-stage, once-through Vacuum Gas Oil (VGO) hydrocracker loaded with a catalyst system providing good cold flow properties for diesel and kerosene at 95% overall conversion. It encapsulates the practical experiences of a Central European refiner from commercial-scale coprocessing trials, highlighting the advantages and challenges, including yields, properties, and operational bottlenecks.
The research investigates the balance between Sustainable Aviation Fuel (SAF) bio content and kerosene cold flow properties through two test runs, each incorporating 5% bio feedstock coprocessing. Findings from these trials reveal that distillation overlaps can be strategically utilized to optimize SAF bio content while adhering to cold flow property specifications fulfilling JET A1 specification.
The initial test run provided insights into the cold-flow characteristics and behavior of paraffins, facilitating the consistent achievement of maximum SAF yields in the subsequent test run. This was achieved through timely SIMDIS analysis of n-alkanes in middle distillate products, serving as an indirect yet effective method for tracking bio-material distribution. SAF yields were ultimately validated by 14C analysis, confirming the feasibility of this approach. We optimized cut point of a jet fraction enabling maximization of retaining green molecules within the kerosene fraction.
Furthermore, coprocessing in hydrocracking (HCK) units results in significantly higher concentrations of HVO compared to coprocessing in hydrodesulfurization (HDT) units.
Finally, evaluated were bottlenecks such as Phosphorus content, CO and/or CO2 formation impacting the unit, and water formation.
Co-author/s:
Martina Valachovičová, MOL.
Peter Andreas Nymann, MOL.
The hydrocracker unit, initially commissioned in 1991 and revamped in 2009 to optimize middle distillate production, mirrors evolving fuel market trends. This study explores the coprocessing of Used Cooking Oil (UCO), not containing palm oil, within a single-stage, once-through Vacuum Gas Oil (VGO) hydrocracker loaded with a catalyst system providing good cold flow properties for diesel and kerosene at 95% overall conversion. It encapsulates the practical experiences of a Central European refiner from commercial-scale coprocessing trials, highlighting the advantages and challenges, including yields, properties, and operational bottlenecks.
The research investigates the balance between Sustainable Aviation Fuel (SAF) bio content and kerosene cold flow properties through two test runs, each incorporating 5% bio feedstock coprocessing. Findings from these trials reveal that distillation overlaps can be strategically utilized to optimize SAF bio content while adhering to cold flow property specifications fulfilling JET A1 specification.
The initial test run provided insights into the cold-flow characteristics and behavior of paraffins, facilitating the consistent achievement of maximum SAF yields in the subsequent test run. This was achieved through timely SIMDIS analysis of n-alkanes in middle distillate products, serving as an indirect yet effective method for tracking bio-material distribution. SAF yields were ultimately validated by 14C analysis, confirming the feasibility of this approach. We optimized cut point of a jet fraction enabling maximization of retaining green molecules within the kerosene fraction.
Furthermore, coprocessing in hydrocracking (HCK) units results in significantly higher concentrations of HVO compared to coprocessing in hydrodesulfurization (HDT) units.
Finally, evaluated were bottlenecks such as Phosphorus content, CO and/or CO2 formation impacting the unit, and water formation.
Co-author/s:
Martina Valachovičová, MOL.
Peter Andreas Nymann, MOL.
Brazil stands out globally for its predominantly renewable energy matrix, which is one of the cleanest in the world. Almost half of Brazil's internal energy supply comes from renewable sources, a very impressive figure compared to the global average. This progressive trajectory in renewable energy reinforces Brazil's leadership in the global energy transition, setting an inspiring model for other nations to follow.
Petrobras, as a leading energy company in Brazil, has been actively involved in initiatives aimed at promoting alternative fuels such as biodiesel, hydrotreated vegetable oil (HVO), bunker with renewable content and sustainable aviation fuel (SAF). Petrobras has already overcome some challenges that other companies are facing right now. About biofuels, in Brazil there are gasoline with 27% ethanol, diesel with 14% biodiesel and bunker fuel with 24% renewables. These were challenges that turned into great opportunities for Petrobras’ portfolio.
Petrobras has a long history of integrating biofuels into its products portfolio . In the 1970s, the company played a pivotal role in introducing ethanol as a blend with gasoline to fuel light fleet vehicles, reducing crude oil imports. This initiative was driven by the need for energy security and has evolved into a significant component of Brazil's energy transition strategy.
In recent years, Petrobras has increased its investments in low-carbon initiatives, which now represent 15% of its total investments, up from 11% in the previous plan. The company has allocated 16 billion US dollars for these investments.
Petrobras has also been pioneering in Brazil the use of co-processing technology as part of its strategy to produce low-carbon fuels. Co-processing involves the simultaneous processing of renewable feedstocks, such as vegetable oils and animal fats, with fossil current in existing hydrotreating units, to produce HVO or SAF. This approach allows for the production of diesel or Jet fuel with a renewable content between 1% to 10%, depending on the characteristics of the hydrotreating unit. The technology offers a cost-effective and agile solution for introducing renewable diesel and SAF into the market, leveraging existing infrastructure and minimizing capital expenditure. Petrobras has successfully implemented diesel co-processing in several of its refineries, with a combined production capacity of 3.6 million cubic meters per year and SAF coprocessing already available in one refinery. The cost of energy transition may weigh more heavily on developing countries so Petrobras seeks for the most beneficial solutions for the country and for the company, such as biofuels and co-processing of renewable loads in existing refining assets.
The main objective of this article is to summarize Petrobras' actions in the energy transition, clarifying specially the challenges and benefits of co-processing sustainable feedstocks, while the company is developing other energy alternatives for the future.
Co-author/s:
Marcelo Antunes Gauto, Manager, Petrobas.
Petrobras, as a leading energy company in Brazil, has been actively involved in initiatives aimed at promoting alternative fuels such as biodiesel, hydrotreated vegetable oil (HVO), bunker with renewable content and sustainable aviation fuel (SAF). Petrobras has already overcome some challenges that other companies are facing right now. About biofuels, in Brazil there are gasoline with 27% ethanol, diesel with 14% biodiesel and bunker fuel with 24% renewables. These were challenges that turned into great opportunities for Petrobras’ portfolio.
Petrobras has a long history of integrating biofuels into its products portfolio . In the 1970s, the company played a pivotal role in introducing ethanol as a blend with gasoline to fuel light fleet vehicles, reducing crude oil imports. This initiative was driven by the need for energy security and has evolved into a significant component of Brazil's energy transition strategy.
In recent years, Petrobras has increased its investments in low-carbon initiatives, which now represent 15% of its total investments, up from 11% in the previous plan. The company has allocated 16 billion US dollars for these investments.
Petrobras has also been pioneering in Brazil the use of co-processing technology as part of its strategy to produce low-carbon fuels. Co-processing involves the simultaneous processing of renewable feedstocks, such as vegetable oils and animal fats, with fossil current in existing hydrotreating units, to produce HVO or SAF. This approach allows for the production of diesel or Jet fuel with a renewable content between 1% to 10%, depending on the characteristics of the hydrotreating unit. The technology offers a cost-effective and agile solution for introducing renewable diesel and SAF into the market, leveraging existing infrastructure and minimizing capital expenditure. Petrobras has successfully implemented diesel co-processing in several of its refineries, with a combined production capacity of 3.6 million cubic meters per year and SAF coprocessing already available in one refinery. The cost of energy transition may weigh more heavily on developing countries so Petrobras seeks for the most beneficial solutions for the country and for the company, such as biofuels and co-processing of renewable loads in existing refining assets.
The main objective of this article is to summarize Petrobras' actions in the energy transition, clarifying specially the challenges and benefits of co-processing sustainable feedstocks, while the company is developing other energy alternatives for the future.
Co-author/s:
Marcelo Antunes Gauto, Manager, Petrobas.
The aviation sector is under increasing pressure to reduce carbon emissions, with the International Air Transport Association (IATA) committing to cut emissions to 50% of 2005 levels by 2050. Sustainable Aviation Fuel (SAF) has emerged as a key solution, offering a near drop-in replacement for conventional Jet A-1 fuel. However, large-scale SAF production faces challenges due to high capital investment and complex multi-step processing in conventional pathways like Hydro processed Esters and Fatty Acids (HEFA).
To address these challenges, Hindustan Petroleum Corporation Limited has developed HP- Triglycerides to Jet fuels (HP-TriJet), an innovative single-step hydroprocessing technology that converts Used Cooking Oil (UCO) into Sustainable Aviation Fuel (SAF) and Green Diesel. Unlike conventional processes that require separate hydrotreating, hydrocracking, and isomerization stages, HP-TriJet seamlessly integrates depropanation, deoxygenation, hydrocracking, and isomerization within a single reactor system, utilizing a proprietary catalyst and optimized process conditions for efficient fuel production
Key features of HP-TriJet include:
India’s Food Safety and Standards Authority (FSSAI) estimates that 3 MMT of UCO can be recovered annually, providing a significant domestic feedstock source for SAF production. In alignment with global decarbonization goals, HPCL has completed the Basic and Front-End Engineering Design for a 7.4 KTPA HP-TriJet plant. With project implementation in progress, HP-TriJet is emerging as a cost-effective and scalable solution for advancing low-carbon aviation and transportation fuels
This game-changing technology provides a sustainable, economically viable, and industrially scalable solution for reducing fossil fuel dependency in the aviation and transport sectors.
To address these challenges, Hindustan Petroleum Corporation Limited has developed HP- Triglycerides to Jet fuels (HP-TriJet), an innovative single-step hydroprocessing technology that converts Used Cooking Oil (UCO) into Sustainable Aviation Fuel (SAF) and Green Diesel. Unlike conventional processes that require separate hydrotreating, hydrocracking, and isomerization stages, HP-TriJet seamlessly integrates depropanation, deoxygenation, hydrocracking, and isomerization within a single reactor system, utilizing a proprietary catalyst and optimized process conditions for efficient fuel production
Key features of HP-TriJet include:
- Flexible product yields: Capable of producing up to 35% SAF (meeting Jet A-1 specifications) or 80% Green Diesel (compliant with EN 15940:2016 Class A standards) based on operating conditions.
- Lower capital and operating costs: A single-step process eliminates the need for multiple reactors and reduces hydrogen consumption, improving economic feasibility.
- Scalability and refinery integration: Enables co-processing with conventional feedstocks, allowing refineries to transition towards renewable fuel production without major infrastructure modifications.
India’s Food Safety and Standards Authority (FSSAI) estimates that 3 MMT of UCO can be recovered annually, providing a significant domestic feedstock source for SAF production. In alignment with global decarbonization goals, HPCL has completed the Basic and Front-End Engineering Design for a 7.4 KTPA HP-TriJet plant. With project implementation in progress, HP-TriJet is emerging as a cost-effective and scalable solution for advancing low-carbon aviation and transportation fuels
This game-changing technology provides a sustainable, economically viable, and industrially scalable solution for reducing fossil fuel dependency in the aviation and transport sectors.
The aviation sector is among the hard to decarbonise sectors due to its reliance on high-energy-density fuels and long technology turnover cycles. While alternative technologies such as hydrogen fuel and electrification remain in early stage, alternative drop-in fuels, especially Sustainable Aviation Fuels (SAFs) and Low-Carbon Aviation Fuels (LCAFs), offer a near- to mid-term solution for emissions reduction, requiring minimal changes to existing aircraft and fuelling infrastructure. However, these fuels continue to face economic and market barriers, including high production costs, limited supply, and inadequate policy support.
For instance, e-kerosene which is a power-to liquid (PtL) sustainable aviation fuel is currently 5 times more expensive than conventional kerosene fuel. If the carbon source of the synthetic PtL fuel is from negative emissions using Direct-Air Capture (DAC), this price gap increases further up to 6 times more expensive than the current price of conventional fuel. Although that the current price of the biomass-based SAF is just around 3 times, however there are resource availability limitation especially in the arid and semi-arid regions, which give rise to energy security issues when these feedstocks are imported from somewhere else. LCAF which is a fossil-based clean aviation fuel exhibits the smallest price difference due to the fact that its price is calculated based on adding a premium equal the abatement cost. However, LCAF only reduce 10% of the lifecycle emissions of the aviation fuel, unlike other SAFs which reach 50-70% reduction.
The Kingdom of Saudi Arabia (KSA) holds a strategic position in global aviation to serve as a connection hub between Europe, Asia, and Africa, while also managing a rapidly growing domestic and international air travel market. As part of KSA Vision 2030, the country aims to transform its aviation sector by tripling its capacity while maintaining environmental sustainability. A major milestone in this effort is the development of Red Sea Airport, which is set to become the first carbon-neutral airport in the region, with Fly Red Sea fuelled exclusively with SAF and LCAF. Despite these opportunities, the sector still relies almost entirely on conventional jet fuels with the absence of any policy incentives to support alternative fuels.
This research proposes a novel design of market-based mechanisms (MBMs) to accelerate the uptake of alternative drop-in fuels in KSA aviation sector. In addition, a novel agent-based model (ABM) was developed to simulate the diffusion pathways for these alternative drop-in fuels under different MBM scenarios in KSA air fleet. The study provides insights on the optimal intervention mixes to accelerate decarbonisation in KSA aviation sector.
Co-author/s:
Gbemi Oluleye, Assistant Professor, Centre for Environmental Policy, Imperial College London.
The transition to net-zero emissions will require scalable, low-carbon alternatives to fossil fuels, particularly in hard-to-decarbonize sectors such as aviation, marine transport, and heavy-duty trucking. Drop-in fuels such as sustainable aviation fuel (SAF), renewable diesel, synthetic gasoline, and renewable natural gas (RNG) offer practical solutions where electrification is not feasible.
This study evaluates eight drop-in fuel production pathways that use either lignocellulosic biomass or captured CO₂ as the carbon source. These include gasification followed by Fischer–Tropsch (FT) synthesis, methanation, and CO₂ conversion via reverse water–gas shift (RWGS) and Sabatier reactions. Hydrogen, a key input, is supplied from either natural gas with carbon capture (blue hydrogen) or electrolysis powered by low-carbon electricity (green hydrogen).
The cost and emissions profile of each pathway depends heavily on the choice of carbon and hydrogen source. Biomass-based FT fuels showed some of the lowest levelized costs, ranging from C$39 per GJ without supplemental hydrogen to C$44 to C$52 per GJ with hydrogen addition, which increases carbon conversion efficiency up to 61 percent. Biomass-to-RNG pathways have similar costs but are more sensitive to methane slip and require effective gas cleanup to meet quality standards. CO₂-derived fuels were consistently more expensive due to the high cost of hydrogen and CO₂ capture. CO₂-to-liquid fuel pathways ranged from C$57 to C$103 per GJ, while CO₂-to-RNG pathways ranged from C$44 to C$82 per GJ. Although these approaches offer long-term carbon circularity and scalability, they remain economically challenging under current market and technology conditions.
Lifecycle greenhouse gas emissions vary significantly depending on the assumed global warming potential (GWP) of the carbon source. If waste biomass or biogenic CO₂ from fermentation is considered climate-neutral (GWP of zero), most pathways reduce emissions by more than 90 percent relative to fossil fuels. However, applying a moderate GWP of 0.3, which reflects delayed natural release of unused carbon, lowers these benefits and can increase abatement costs to more than C$700 per tonne of CO₂ avoided. Fossil CO₂ and direct air capture (DAC), modeled with a GWP of 1, remain costly but are less affected by accounting assumptions.
Hydrogen source also plays a critical role. Blue hydrogen enables lower costs and earlier deployment but requires large-scale CO₂ storage. Green hydrogen offers deeper decarbonization but demands significant electricity, which may exceed current grid capacity in some regions. Rather than pointing to one ideal option, the findings suggest that a mix of technologies will be needed. Biomass-based systems with blue hydrogen may provide near-term opportunities, while CO₂-derived fuels could gain traction as enabling technologies mature.
Co-author/s:
Mohd Adnan Khan, Environemnt Specialist and Lead Scientist, Saudi Aramco.
David Layzell, Professor, Transition Accelerator.
Md Kibria, Associate Professor, University of Calgary.
Shariful Nabil, PhD Student, University of Calgary.
This study evaluates eight drop-in fuel production pathways that use either lignocellulosic biomass or captured CO₂ as the carbon source. These include gasification followed by Fischer–Tropsch (FT) synthesis, methanation, and CO₂ conversion via reverse water–gas shift (RWGS) and Sabatier reactions. Hydrogen, a key input, is supplied from either natural gas with carbon capture (blue hydrogen) or electrolysis powered by low-carbon electricity (green hydrogen).
The cost and emissions profile of each pathway depends heavily on the choice of carbon and hydrogen source. Biomass-based FT fuels showed some of the lowest levelized costs, ranging from C$39 per GJ without supplemental hydrogen to C$44 to C$52 per GJ with hydrogen addition, which increases carbon conversion efficiency up to 61 percent. Biomass-to-RNG pathways have similar costs but are more sensitive to methane slip and require effective gas cleanup to meet quality standards. CO₂-derived fuels were consistently more expensive due to the high cost of hydrogen and CO₂ capture. CO₂-to-liquid fuel pathways ranged from C$57 to C$103 per GJ, while CO₂-to-RNG pathways ranged from C$44 to C$82 per GJ. Although these approaches offer long-term carbon circularity and scalability, they remain economically challenging under current market and technology conditions.
Lifecycle greenhouse gas emissions vary significantly depending on the assumed global warming potential (GWP) of the carbon source. If waste biomass or biogenic CO₂ from fermentation is considered climate-neutral (GWP of zero), most pathways reduce emissions by more than 90 percent relative to fossil fuels. However, applying a moderate GWP of 0.3, which reflects delayed natural release of unused carbon, lowers these benefits and can increase abatement costs to more than C$700 per tonne of CO₂ avoided. Fossil CO₂ and direct air capture (DAC), modeled with a GWP of 1, remain costly but are less affected by accounting assumptions.
Hydrogen source also plays a critical role. Blue hydrogen enables lower costs and earlier deployment but requires large-scale CO₂ storage. Green hydrogen offers deeper decarbonization but demands significant electricity, which may exceed current grid capacity in some regions. Rather than pointing to one ideal option, the findings suggest that a mix of technologies will be needed. Biomass-based systems with blue hydrogen may provide near-term opportunities, while CO₂-derived fuels could gain traction as enabling technologies mature.
Co-author/s:
Mohd Adnan Khan, Environemnt Specialist and Lead Scientist, Saudi Aramco.
David Layzell, Professor, Transition Accelerator.
Md Kibria, Associate Professor, University of Calgary.
Shariful Nabil, PhD Student, University of Calgary.
Leif-Erik Schulte
Chair
Executive Vice President
IFM - Institute for Vehicle Technology and Mobility, TÜV NORD Mobilität GmbH & Co. KG
The transition to net-zero emissions will require scalable, low-carbon alternatives to fossil fuels, particularly in hard-to-decarbonize sectors such as aviation, marine transport, and heavy-duty trucking. Drop-in fuels such as sustainable aviation fuel (SAF), renewable diesel, synthetic gasoline, and renewable natural gas (RNG) offer practical solutions where electrification is not feasible.
This study evaluates eight drop-in fuel production pathways that use either lignocellulosic biomass or captured CO₂ as the carbon source. These include gasification followed by Fischer–Tropsch (FT) synthesis, methanation, and CO₂ conversion via reverse water–gas shift (RWGS) and Sabatier reactions. Hydrogen, a key input, is supplied from either natural gas with carbon capture (blue hydrogen) or electrolysis powered by low-carbon electricity (green hydrogen).
The cost and emissions profile of each pathway depends heavily on the choice of carbon and hydrogen source. Biomass-based FT fuels showed some of the lowest levelized costs, ranging from C$39 per GJ without supplemental hydrogen to C$44 to C$52 per GJ with hydrogen addition, which increases carbon conversion efficiency up to 61 percent. Biomass-to-RNG pathways have similar costs but are more sensitive to methane slip and require effective gas cleanup to meet quality standards. CO₂-derived fuels were consistently more expensive due to the high cost of hydrogen and CO₂ capture. CO₂-to-liquid fuel pathways ranged from C$57 to C$103 per GJ, while CO₂-to-RNG pathways ranged from C$44 to C$82 per GJ. Although these approaches offer long-term carbon circularity and scalability, they remain economically challenging under current market and technology conditions.
Lifecycle greenhouse gas emissions vary significantly depending on the assumed global warming potential (GWP) of the carbon source. If waste biomass or biogenic CO₂ from fermentation is considered climate-neutral (GWP of zero), most pathways reduce emissions by more than 90 percent relative to fossil fuels. However, applying a moderate GWP of 0.3, which reflects delayed natural release of unused carbon, lowers these benefits and can increase abatement costs to more than C$700 per tonne of CO₂ avoided. Fossil CO₂ and direct air capture (DAC), modeled with a GWP of 1, remain costly but are less affected by accounting assumptions.
Hydrogen source also plays a critical role. Blue hydrogen enables lower costs and earlier deployment but requires large-scale CO₂ storage. Green hydrogen offers deeper decarbonization but demands significant electricity, which may exceed current grid capacity in some regions. Rather than pointing to one ideal option, the findings suggest that a mix of technologies will be needed. Biomass-based systems with blue hydrogen may provide near-term opportunities, while CO₂-derived fuels could gain traction as enabling technologies mature.
Co-author/s:
Mohd Adnan Khan, Environemnt Specialist and Lead Scientist, Saudi Aramco.
David Layzell, Professor, Transition Accelerator.
Md Kibria, Associate Professor, University of Calgary.
Shariful Nabil, PhD Student, University of Calgary.
This study evaluates eight drop-in fuel production pathways that use either lignocellulosic biomass or captured CO₂ as the carbon source. These include gasification followed by Fischer–Tropsch (FT) synthesis, methanation, and CO₂ conversion via reverse water–gas shift (RWGS) and Sabatier reactions. Hydrogen, a key input, is supplied from either natural gas with carbon capture (blue hydrogen) or electrolysis powered by low-carbon electricity (green hydrogen).
The cost and emissions profile of each pathway depends heavily on the choice of carbon and hydrogen source. Biomass-based FT fuels showed some of the lowest levelized costs, ranging from C$39 per GJ without supplemental hydrogen to C$44 to C$52 per GJ with hydrogen addition, which increases carbon conversion efficiency up to 61 percent. Biomass-to-RNG pathways have similar costs but are more sensitive to methane slip and require effective gas cleanup to meet quality standards. CO₂-derived fuels were consistently more expensive due to the high cost of hydrogen and CO₂ capture. CO₂-to-liquid fuel pathways ranged from C$57 to C$103 per GJ, while CO₂-to-RNG pathways ranged from C$44 to C$82 per GJ. Although these approaches offer long-term carbon circularity and scalability, they remain economically challenging under current market and technology conditions.
Lifecycle greenhouse gas emissions vary significantly depending on the assumed global warming potential (GWP) of the carbon source. If waste biomass or biogenic CO₂ from fermentation is considered climate-neutral (GWP of zero), most pathways reduce emissions by more than 90 percent relative to fossil fuels. However, applying a moderate GWP of 0.3, which reflects delayed natural release of unused carbon, lowers these benefits and can increase abatement costs to more than C$700 per tonne of CO₂ avoided. Fossil CO₂ and direct air capture (DAC), modeled with a GWP of 1, remain costly but are less affected by accounting assumptions.
Hydrogen source also plays a critical role. Blue hydrogen enables lower costs and earlier deployment but requires large-scale CO₂ storage. Green hydrogen offers deeper decarbonization but demands significant electricity, which may exceed current grid capacity in some regions. Rather than pointing to one ideal option, the findings suggest that a mix of technologies will be needed. Biomass-based systems with blue hydrogen may provide near-term opportunities, while CO₂-derived fuels could gain traction as enabling technologies mature.
Co-author/s:
Mohd Adnan Khan, Environemnt Specialist and Lead Scientist, Saudi Aramco.
David Layzell, Professor, Transition Accelerator.
Md Kibria, Associate Professor, University of Calgary.
Shariful Nabil, PhD Student, University of Calgary.
Ahmed AlJameel
Speaker
Energy & Climate Policy Researcher
Centre for Environmental Policy, Imperial College London
The aviation sector is among the hard to decarbonise sectors due to its reliance on high-energy-density fuels and long technology turnover cycles. While alternative technologies such as hydrogen fuel and electrification remain in early stage, alternative drop-in fuels, especially Sustainable Aviation Fuels (SAFs) and Low-Carbon Aviation Fuels (LCAFs), offer a near- to mid-term solution for emissions reduction, requiring minimal changes to existing aircraft and fuelling infrastructure. However, these fuels continue to face economic and market barriers, including high production costs, limited supply, and inadequate policy support.
For instance, e-kerosene which is a power-to liquid (PtL) sustainable aviation fuel is currently 5 times more expensive than conventional kerosene fuel. If the carbon source of the synthetic PtL fuel is from negative emissions using Direct-Air Capture (DAC), this price gap increases further up to 6 times more expensive than the current price of conventional fuel. Although that the current price of the biomass-based SAF is just around 3 times, however there are resource availability limitation especially in the arid and semi-arid regions, which give rise to energy security issues when these feedstocks are imported from somewhere else. LCAF which is a fossil-based clean aviation fuel exhibits the smallest price difference due to the fact that its price is calculated based on adding a premium equal the abatement cost. However, LCAF only reduce 10% of the lifecycle emissions of the aviation fuel, unlike other SAFs which reach 50-70% reduction.
The Kingdom of Saudi Arabia (KSA) holds a strategic position in global aviation to serve as a connection hub between Europe, Asia, and Africa, while also managing a rapidly growing domestic and international air travel market. As part of KSA Vision 2030, the country aims to transform its aviation sector by tripling its capacity while maintaining environmental sustainability. A major milestone in this effort is the development of Red Sea Airport, which is set to become the first carbon-neutral airport in the region, with Fly Red Sea fuelled exclusively with SAF and LCAF. Despite these opportunities, the sector still relies almost entirely on conventional jet fuels with the absence of any policy incentives to support alternative fuels.
This research proposes a novel design of market-based mechanisms (MBMs) to accelerate the uptake of alternative drop-in fuels in KSA aviation sector. In addition, a novel agent-based model (ABM) was developed to simulate the diffusion pathways for these alternative drop-in fuels under different MBM scenarios in KSA air fleet. The study provides insights on the optimal intervention mixes to accelerate decarbonisation in KSA aviation sector.
Co-author/s:
Gbemi Oluleye, Assistant Professor, Centre for Environmental Policy, Imperial College London.
For instance, e-kerosene which is a power-to liquid (PtL) sustainable aviation fuel is currently 5 times more expensive than conventional kerosene fuel. If the carbon source of the synthetic PtL fuel is from negative emissions using Direct-Air Capture (DAC), this price gap increases further up to 6 times more expensive than the current price of conventional fuel. Although that the current price of the biomass-based SAF is just around 3 times, however there are resource availability limitation especially in the arid and semi-arid regions, which give rise to energy security issues when these feedstocks are imported from somewhere else. LCAF which is a fossil-based clean aviation fuel exhibits the smallest price difference due to the fact that its price is calculated based on adding a premium equal the abatement cost. However, LCAF only reduce 10% of the lifecycle emissions of the aviation fuel, unlike other SAFs which reach 50-70% reduction.
The Kingdom of Saudi Arabia (KSA) holds a strategic position in global aviation to serve as a connection hub between Europe, Asia, and Africa, while also managing a rapidly growing domestic and international air travel market. As part of KSA Vision 2030, the country aims to transform its aviation sector by tripling its capacity while maintaining environmental sustainability. A major milestone in this effort is the development of Red Sea Airport, which is set to become the first carbon-neutral airport in the region, with Fly Red Sea fuelled exclusively with SAF and LCAF. Despite these opportunities, the sector still relies almost entirely on conventional jet fuels with the absence of any policy incentives to support alternative fuels.
This research proposes a novel design of market-based mechanisms (MBMs) to accelerate the uptake of alternative drop-in fuels in KSA aviation sector. In addition, a novel agent-based model (ABM) was developed to simulate the diffusion pathways for these alternative drop-in fuels under different MBM scenarios in KSA air fleet. The study provides insights on the optimal intervention mixes to accelerate decarbonisation in KSA aviation sector.
Co-author/s:
Gbemi Oluleye, Assistant Professor, Centre for Environmental Policy, Imperial College London.
Brazil stands out globally for its predominantly renewable energy matrix, which is one of the cleanest in the world. Almost half of Brazil's internal energy supply comes from renewable sources, a very impressive figure compared to the global average. This progressive trajectory in renewable energy reinforces Brazil's leadership in the global energy transition, setting an inspiring model for other nations to follow.
Petrobras, as a leading energy company in Brazil, has been actively involved in initiatives aimed at promoting alternative fuels such as biodiesel, hydrotreated vegetable oil (HVO), bunker with renewable content and sustainable aviation fuel (SAF). Petrobras has already overcome some challenges that other companies are facing right now. About biofuels, in Brazil there are gasoline with 27% ethanol, diesel with 14% biodiesel and bunker fuel with 24% renewables. These were challenges that turned into great opportunities for Petrobras’ portfolio.
Petrobras has a long history of integrating biofuels into its products portfolio . In the 1970s, the company played a pivotal role in introducing ethanol as a blend with gasoline to fuel light fleet vehicles, reducing crude oil imports. This initiative was driven by the need for energy security and has evolved into a significant component of Brazil's energy transition strategy.
In recent years, Petrobras has increased its investments in low-carbon initiatives, which now represent 15% of its total investments, up from 11% in the previous plan. The company has allocated 16 billion US dollars for these investments.
Petrobras has also been pioneering in Brazil the use of co-processing technology as part of its strategy to produce low-carbon fuels. Co-processing involves the simultaneous processing of renewable feedstocks, such as vegetable oils and animal fats, with fossil current in existing hydrotreating units, to produce HVO or SAF. This approach allows for the production of diesel or Jet fuel with a renewable content between 1% to 10%, depending on the characteristics of the hydrotreating unit. The technology offers a cost-effective and agile solution for introducing renewable diesel and SAF into the market, leveraging existing infrastructure and minimizing capital expenditure. Petrobras has successfully implemented diesel co-processing in several of its refineries, with a combined production capacity of 3.6 million cubic meters per year and SAF coprocessing already available in one refinery. The cost of energy transition may weigh more heavily on developing countries so Petrobras seeks for the most beneficial solutions for the country and for the company, such as biofuels and co-processing of renewable loads in existing refining assets.
The main objective of this article is to summarize Petrobras' actions in the energy transition, clarifying specially the challenges and benefits of co-processing sustainable feedstocks, while the company is developing other energy alternatives for the future.
Co-author/s:
Marcelo Antunes Gauto, Manager, Petrobas.
Petrobras, as a leading energy company in Brazil, has been actively involved in initiatives aimed at promoting alternative fuels such as biodiesel, hydrotreated vegetable oil (HVO), bunker with renewable content and sustainable aviation fuel (SAF). Petrobras has already overcome some challenges that other companies are facing right now. About biofuels, in Brazil there are gasoline with 27% ethanol, diesel with 14% biodiesel and bunker fuel with 24% renewables. These were challenges that turned into great opportunities for Petrobras’ portfolio.
Petrobras has a long history of integrating biofuels into its products portfolio . In the 1970s, the company played a pivotal role in introducing ethanol as a blend with gasoline to fuel light fleet vehicles, reducing crude oil imports. This initiative was driven by the need for energy security and has evolved into a significant component of Brazil's energy transition strategy.
In recent years, Petrobras has increased its investments in low-carbon initiatives, which now represent 15% of its total investments, up from 11% in the previous plan. The company has allocated 16 billion US dollars for these investments.
Petrobras has also been pioneering in Brazil the use of co-processing technology as part of its strategy to produce low-carbon fuels. Co-processing involves the simultaneous processing of renewable feedstocks, such as vegetable oils and animal fats, with fossil current in existing hydrotreating units, to produce HVO or SAF. This approach allows for the production of diesel or Jet fuel with a renewable content between 1% to 10%, depending on the characteristics of the hydrotreating unit. The technology offers a cost-effective and agile solution for introducing renewable diesel and SAF into the market, leveraging existing infrastructure and minimizing capital expenditure. Petrobras has successfully implemented diesel co-processing in several of its refineries, with a combined production capacity of 3.6 million cubic meters per year and SAF coprocessing already available in one refinery. The cost of energy transition may weigh more heavily on developing countries so Petrobras seeks for the most beneficial solutions for the country and for the company, such as biofuels and co-processing of renewable loads in existing refining assets.
The main objective of this article is to summarize Petrobras' actions in the energy transition, clarifying specially the challenges and benefits of co-processing sustainable feedstocks, while the company is developing other energy alternatives for the future.
Co-author/s:
Marcelo Antunes Gauto, Manager, Petrobas.
Srinivasa Rao Ganagalla
Speaker
Senior Manager - R&D
Hindustan Petroleum Corporation Limited
The aviation sector is under increasing pressure to reduce carbon emissions, with the International Air Transport Association (IATA) committing to cut emissions to 50% of 2005 levels by 2050. Sustainable Aviation Fuel (SAF) has emerged as a key solution, offering a near drop-in replacement for conventional Jet A-1 fuel. However, large-scale SAF production faces challenges due to high capital investment and complex multi-step processing in conventional pathways like Hydro processed Esters and Fatty Acids (HEFA).
To address these challenges, Hindustan Petroleum Corporation Limited has developed HP- Triglycerides to Jet fuels (HP-TriJet), an innovative single-step hydroprocessing technology that converts Used Cooking Oil (UCO) into Sustainable Aviation Fuel (SAF) and Green Diesel. Unlike conventional processes that require separate hydrotreating, hydrocracking, and isomerization stages, HP-TriJet seamlessly integrates depropanation, deoxygenation, hydrocracking, and isomerization within a single reactor system, utilizing a proprietary catalyst and optimized process conditions for efficient fuel production
Key features of HP-TriJet include:
India’s Food Safety and Standards Authority (FSSAI) estimates that 3 MMT of UCO can be recovered annually, providing a significant domestic feedstock source for SAF production. In alignment with global decarbonization goals, HPCL has completed the Basic and Front-End Engineering Design for a 7.4 KTPA HP-TriJet plant. With project implementation in progress, HP-TriJet is emerging as a cost-effective and scalable solution for advancing low-carbon aviation and transportation fuels
This game-changing technology provides a sustainable, economically viable, and industrially scalable solution for reducing fossil fuel dependency in the aviation and transport sectors.
To address these challenges, Hindustan Petroleum Corporation Limited has developed HP- Triglycerides to Jet fuels (HP-TriJet), an innovative single-step hydroprocessing technology that converts Used Cooking Oil (UCO) into Sustainable Aviation Fuel (SAF) and Green Diesel. Unlike conventional processes that require separate hydrotreating, hydrocracking, and isomerization stages, HP-TriJet seamlessly integrates depropanation, deoxygenation, hydrocracking, and isomerization within a single reactor system, utilizing a proprietary catalyst and optimized process conditions for efficient fuel production
Key features of HP-TriJet include:
- Flexible product yields: Capable of producing up to 35% SAF (meeting Jet A-1 specifications) or 80% Green Diesel (compliant with EN 15940:2016 Class A standards) based on operating conditions.
- Lower capital and operating costs: A single-step process eliminates the need for multiple reactors and reduces hydrogen consumption, improving economic feasibility.
- Scalability and refinery integration: Enables co-processing with conventional feedstocks, allowing refineries to transition towards renewable fuel production without major infrastructure modifications.
India’s Food Safety and Standards Authority (FSSAI) estimates that 3 MMT of UCO can be recovered annually, providing a significant domestic feedstock source for SAF production. In alignment with global decarbonization goals, HPCL has completed the Basic and Front-End Engineering Design for a 7.4 KTPA HP-TriJet plant. With project implementation in progress, HP-TriJet is emerging as a cost-effective and scalable solution for advancing low-carbon aviation and transportation fuels
This game-changing technology provides a sustainable, economically viable, and industrially scalable solution for reducing fossil fuel dependency in the aviation and transport sectors.
In the mission to address climate change and secure a sustainable future, biofuels emerge as a source of optimism. By significantly reducing greenhouse gas emissions, biofuels not only enhance air quality but also mitigate environmental degradation. They offer a pathway to energy independence, diminishing our reliance on depleting fossil fuel reserves. Embracing biofuels is more than an environmental choice; it's a stride towards economic resilience and sustainable development. Recently, the spotlight has turned to hydrocracking units in biofuel production, unveiling promising avenues for creating Hydrotreated Vegetable Oil (HVO) and Sustainable Aviation Fuel (SAF). These advancements underscore the transformative potential of biofuels in our journey towards a cleaner planet, reducing CO2 emissions from fossil feedstocks.
The hydrocracker unit, initially commissioned in 1991 and revamped in 2009 to optimize middle distillate production, mirrors evolving fuel market trends. This study explores the coprocessing of Used Cooking Oil (UCO), not containing palm oil, within a single-stage, once-through Vacuum Gas Oil (VGO) hydrocracker loaded with a catalyst system providing good cold flow properties for diesel and kerosene at 95% overall conversion. It encapsulates the practical experiences of a Central European refiner from commercial-scale coprocessing trials, highlighting the advantages and challenges, including yields, properties, and operational bottlenecks.
The research investigates the balance between Sustainable Aviation Fuel (SAF) bio content and kerosene cold flow properties through two test runs, each incorporating 5% bio feedstock coprocessing. Findings from these trials reveal that distillation overlaps can be strategically utilized to optimize SAF bio content while adhering to cold flow property specifications fulfilling JET A1 specification.
The initial test run provided insights into the cold-flow characteristics and behavior of paraffins, facilitating the consistent achievement of maximum SAF yields in the subsequent test run. This was achieved through timely SIMDIS analysis of n-alkanes in middle distillate products, serving as an indirect yet effective method for tracking bio-material distribution. SAF yields were ultimately validated by 14C analysis, confirming the feasibility of this approach. We optimized cut point of a jet fraction enabling maximization of retaining green molecules within the kerosene fraction.
Furthermore, coprocessing in hydrocracking (HCK) units results in significantly higher concentrations of HVO compared to coprocessing in hydrodesulfurization (HDT) units.
Finally, evaluated were bottlenecks such as Phosphorus content, CO and/or CO2 formation impacting the unit, and water formation.
Co-author/s:
Martina Valachovičová, MOL.
Peter Andreas Nymann, MOL.
The hydrocracker unit, initially commissioned in 1991 and revamped in 2009 to optimize middle distillate production, mirrors evolving fuel market trends. This study explores the coprocessing of Used Cooking Oil (UCO), not containing palm oil, within a single-stage, once-through Vacuum Gas Oil (VGO) hydrocracker loaded with a catalyst system providing good cold flow properties for diesel and kerosene at 95% overall conversion. It encapsulates the practical experiences of a Central European refiner from commercial-scale coprocessing trials, highlighting the advantages and challenges, including yields, properties, and operational bottlenecks.
The research investigates the balance between Sustainable Aviation Fuel (SAF) bio content and kerosene cold flow properties through two test runs, each incorporating 5% bio feedstock coprocessing. Findings from these trials reveal that distillation overlaps can be strategically utilized to optimize SAF bio content while adhering to cold flow property specifications fulfilling JET A1 specification.
The initial test run provided insights into the cold-flow characteristics and behavior of paraffins, facilitating the consistent achievement of maximum SAF yields in the subsequent test run. This was achieved through timely SIMDIS analysis of n-alkanes in middle distillate products, serving as an indirect yet effective method for tracking bio-material distribution. SAF yields were ultimately validated by 14C analysis, confirming the feasibility of this approach. We optimized cut point of a jet fraction enabling maximization of retaining green molecules within the kerosene fraction.
Furthermore, coprocessing in hydrocracking (HCK) units results in significantly higher concentrations of HVO compared to coprocessing in hydrodesulfurization (HDT) units.
Finally, evaluated were bottlenecks such as Phosphorus content, CO and/or CO2 formation impacting the unit, and water formation.
Co-author/s:
Martina Valachovičová, MOL.
Peter Andreas Nymann, MOL.
