Sustainable Aviation Fuel (SAF) is a key component in the global pursuit of a greener aviation sector. It is a “drop-in” fuel that can be used in today’s aircraft engines and refuelling infrastructure with only minor modifications. SAF is the only viable solution for decarbonising long-haul flights by 2050 – both hydrogen and battery-electric powered planes are coming, but they are potentially decades away. Aviation’s year-on-year emissions have been growing significantly faster than those of other transport sectors, UK aviation specifically contributes 8% of collective UK emissions. The sector needs to decarbonise to ensure we retain the economic and social benefits of flying.
SAF can be produced from a wide range of renewable sources, such as biomass, household or municipal solid waste, used cooking oil, algae, or animal fats. It provides an alternative fuel solution to reduce the sector’s carbon footprint while decreasing dependence on finite fossil fuels that currently power the majority of commercial flights.
Lighthouse Green Fuels (LGF), located in Teesside, UK, is set to become Europe’s largest advanced SAF facility. LGF is being developed by Alfanar Group, a privately-owned conglomerate specialising in manufacturing, engineering, construction, and integrated project development. LGF will process biogenic waste and residue feedstocks into advanced 2nd generation SAF.
Over 1 million tonnes of biogenic feedstock, such as waste wood, forest residues and other biomass wastes, will be processed each year generating over 130,000 tonnes of 2nd generation SAF (equivalent to over 175 million litres) and over 20,000 tonnes of green naphtha (equivalent to over 30 million litres). SAF produced by the plant will account for over 10% of the UK Government’s 2030 SAF target of ~1.2 million tonnes.
Dr. Simon Owens, Technical and Engineering Director of Alfanar Projects, has outlined LGF’s Sustainable Aviation Fuel production process and provided further technology insights below.
LGF will utilise the Gasification + Fischer Tropsch (FT) route to convert waste- or residue-based feedstocks into 2nd generation SAF – designated Fischer Tropsch synthetic paraffinic kerosene (FT-SPK). FT-SPK is one of the ASTM-certified production pathways alongside SAF derived from hydroprocessed esters and fatty acids (HEFA), alcohol-to-jet (ATJ) and several others (ref. ASTM D7566 Annexures). Currently, FT-SPK must be blended with conventional fossil-derived kerosene in accordance with the ASTM standards, however, 100% SAF usage in aircraft engines is envisaged in the near future after further testing by aircraft engine manufacturers and ASTM.
Producing 2nd generation SAF from solid feedstocks involves a complex process involving several established technologies but assembled in an innovative way. Prior to conversion in the LGF plant, feedstocks are pre-processed to remove major contaminants such as metals or inert material. The first step in the LGF SAF production process is gasification. Here, the solid feedstock is converted into a synthesis gas (“syngas”) via a thermochemical process in the presence of oxygen and/or steam. The produced syngas is made up of predominantly carbon monoxide (CO), hydrogen (H2) and carbon dioxide (CO2) with smaller quantities of methane and contaminant species. Following gasification, the crude syngas is cleaned in a series of conventional wet scrubbing technologies to remove major contaminant species and unwanted particulate matter.
The syngas is then further cleaned in the syngas clean-up section of the LGF plant. Here, adsorbent, and catalytic process steps remove the residual minor contaminant species. Acid gas components, such as CO2 and sulphur species, are also removed by the acid gas removal unit (AGRU). CO2 removed from the syngas is purified to >99% purity, which meets meeting the requirements for injection into the local carbon capture and storage (CCS) network in Teesside – Net Zero Teesside. LGF plans to sequester CO2, subject to availability and access to the network. Another key part of this section of the plant is the water-gas shift (WGS) reactor. In the WGS the ratio of H2 to CO is adjusted to approximately 2:1. This ratio is required by downstream synthesis process steps.
After the syngas clean-up section, the ultra-clean syngas is directed to the FT reactor to be converted into liquid hydrocarbon waxes (also known as synthetic crude or “syncrude”). CO and H2 are reacted over a cobalt-based catalyst at elevated temperature (150 – 300 °C) and pressure (>30 bar) to produce long-chain paraffinic hydrocarbon molecules (waxes). Alongside the waxes the FT unit also produces a “tailgas” made up of light hydrocarbons and methane. These valuable process gases can be recycled to other parts of the process to improve overall efficiency or generate power.
Waxes from the FT reactor are refined in the product upgrading unit, which contains similar process unit operations to a conventional refinery. The upgrading unit features a hydrocracker unit to “crack” the waxes into shorter chain hydrocarbons falling into the middle distillates range (C10 – C20 carbon chain length). Distillation is used to separate the SAF (FT-SPK) and naphtha products.. Final products are tested before being sent to a neighbouring tank farm for storage and export.
Carbon capture is an important factor in producing SAF in the UK. The UK SAF Mandate (developed and administered by Department for Transport) is carbon-scaling – meaning the lower the carbon intensity of the SAF the higher number of SAF credits will be awarded. Carbon capture technology coupled with access to permanent storage (such as the Net Zero Teesside infrastructure) will enable LGF to significantly reduce the carbon intensity (measured in gCO2e/MJ) of the SAF generated by the plant. As explained in earlier paragraphs, the LGF plant must remove CO2 from the syngas are part of the core process to produce a syngas suitable for conversion into liquid fuels. The plant is therefore inherently “carbon capture enabled” – unlike other emitters who are “bolting on” carbon capture technologies to abate their emissions. If CO2 storage capacity is provided to the LGF plant, hundreds of thousands of tonnes of biogenic CO2 can be locked away. In this scenario, LGF’s SAF has a negative emission profile, i.e. the SAF production process removes more CO2 from the atmosphere than it generates, thereby significantly accelerating the decarbonisation of the national aviation sector. Our greenhouse gas (GHG) assessments are developed by an independent third-party consultant and ultimately verified by Department for Transport (DfT) in order for the project to receive SAF credits.
LGF not only marks a milestone in SAF production on a commercial scale nationally, it offers significant socio-economic benefits to the Teesside region by acting as a catalyst for economic growth. With a substantial £1.5 billion investment, the project aims to establish an economic hub in Teesside related to renewable fuels. During the construction phase alone, it is expected to generate over £470 million Gross Value Added (GVA) for the UK, providing a boost to the national economy. Additionally, it will create over 1,600 jobs across in the region, fostering employment opportunities and supporting local communities.
Establishing a domestic SAF market will improve national energy security and avoid dependence on imported alternative fuels. Domestically produced SAF will help maintain lower ticket prices compared to relying on imported SAF. It will also reduce the economic cost to UK PLC associated with import fees.
The opportunity for the UK to become a global leader in SAF production is substantial. With the third-largest aviation network globally, contributing £22 billion annually to the economy, and significant CO2 storage potential, the UK is well-positioned for leadership in sustainable aviation. LGF’s Teesside facility serves as a crucial stepping stone, laying the foundation for the UK to secure a prominent position in the evolving market. The project’s ambition extends beyond this facility, as Teesside is to become the hub for Alfanar’s new global transport decarbonisation division. By the time LGF starts commercial operation, Alfanar plans to have at least two more SAF plants under development, with an ambitious target of over 5% market share of European advanced SAF production by 2040.