Tareq Al-Attas
R&D Associate
University of Calgary
Dr. Al-Attas is an R&D associate at O Two Carbon Inc., a startup linked to the University of Calgary. He holds a Ph.D. in Chemical Engineering with expertise in electrochemical systems and low-carbon fuel production. He has published on CO₂ utilization, H₂ production, and electrified drop-in fuel pathways. He has led TEA/LCA studies of clean fuel systems and contributed to decarbonization work supported by Canadian innovation agencies. His collaborations span Canada, the U.S., and Saudi Arabia.
Participates in
TECHNICAL PROGRAMME | Energy Fuels and Molecules
Alternative Fuels - E fuels, Biofuels and SAF
Forum 15 | Technical Programme Hall 3
28
April
14:30
16:00
UTC+3
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.
