Beyond the HEFA Tipping Point: What Does the Future Hold for Biofuels?

 

Sustainable aviation fuel (SAF) production must scale up to decarbonize aviation globally. The HEFA pathway - which involves extraction of oils, followed by hydrotreatment, isomerization and hydrocracking processes similar to petroleum refining - provides a (relatively) low cost pathway to SAF. However, the feedstocks for HEFA/HVO processes are finite. At some point beyond 2030, global SAF demand will outpace availability of HEFA SAF: this has been referred to by industry as "the HEFA tipping point". IDTechEx's "Sustainable Biofuels & E-Fuels Market 2026-2036: Technologies, Players, Forecasts" report, which forecasts global SAF capacity through to 2036, analyses emerging alternative SAF technologies.

 

 

The ATJ (alcohol-to-jet) process upgrades ethanol or methanol into hydrocarbon fuels suitable for blending with petroleum jet fuel. Dehydration, followed by oligomerization, hydrogenation & isomerization, and distillation produces kerosene and byproducts such as renewable diesel and gasoline. While currently more expensive than the HEFA pathway, this technology will become increasingly appealing as the HEFA tipping point is approached. Examples of players developing technologies for this pathway include ExxonMobil, Honeywell UOP, LanzaJet, and Axens.

 

 

One further consideration is that ethanol itself is a first-generation biofuel, and its green credentials are often debated when considering factors such as land use change. This will lead to an eventual phase-out of conventional bioethanol in key regions such as the European Union. However, the alcohol-to-jet pathway will still be viable via other routes. According to IDTechEx's "Sustainable Biofuels & E-Fuels Market 2026-2036: Technologies, Players, Forecasts" report, bioethanol can also be produced via low-carbon feedstocks such as captured carbon dioxide and cellulose.

 

Cellulosic ethanol production is a complex and expensive process compared to conventional ethanol production. As a result, there have been several notable project failures within the past 12 years, but there have been success stories as well. There are now several facilities around the globe that produce cellulosic ethanol on the ~10,000 tonnes per annum scale from players such as Raízen and Versalis. The anticipated global increase in SAF demand may well create more demand for cellulosic ethanol via the alcohol-to-jet pathway.

 

 

 

 

 

Gasification of biomass produces syngas, which can be used for the production of bio-hydrogen, methanol, or longer chain hydrocarbon fuels (such as diesel or kerosene/jet-fuel). Biomethanol markets hold the most promise in the near-term. While biogas reforming has historically been the leading technology for biomethanol, this will soon be surpassed by the number of new gasification projects because producing biomethanol via biomass gasification has lower upfront costs and a quicker payback time. Global demand for low-carbon methanol is being driven by demand for clean marine fuels, decarbonization of the chemical sector, and as a feedstock for the SAF (via the methanol-to-jet pathway).

 

There are fewer project developers targeting SAF via the gasification/Fischer Tropsch route. IDTechEx notes key lessons must be learned from past failures, such as the technical issues that caused the close down of Fulcrum BioEnergy's plant in Nevada.

 

 

Other biofuel pathways are being explored, but these are generally at a lower technology readiness level (TRL). Hydrothermal liquefaction and pyrolysis oil upgrading are promising but the number of companies active in this space is comparatively small. Additionally, third generation algae biofuels hold significant potential, but more widespread commercial-scale production of these biofuels is likely over a decade away.

 

 

 

For sustainable aviation fuels and renewable diesel, the HEFA/HVO pathway will continue to dominate production. However, the long-term success of decarbonizing global transportation requires alternative routes. These include other second generation biofuel pathways such as alcohol-to-jet and gasification, but also technologies such as e-fuels and algae fuels. IDTechEx's "Sustainable Biofuels & E-Fuels Market 2026-2036: Technologies, Players, Forecasts" report analyzes emerging e-fuel and biofuel technologies, identifying key players, alongside drivers and barriers for sustainable fuel market growth.

 

For more information on this report, including downloadable sample pages, please visit www.IDTechEx.com/Biofuels, or for the full portfolio of research available from IDTechEx, see www.IDTechEx.com.