Decarbonisation Technology November 2025 Issue

Produce build-ready engineering package Detailed Design FEL-4

Conceptual

Feasibility FEL-1

PreFEED FEL-2

FEED FEL-3

Clarify scope, de-risk, project and tighten cost certainty

Scenario modeling and optimisation

Validate optimised scenario feasibility

Finalise design, rene cost certainty

Goal

Estimate class

Class 4

Class 3

Class 2

Class 1

Class 5

65% to 100%

Deliverable maturity

0% to 2%

1% to 15%

10% to 40%

30% to 75%

Innovation-driven model

Figure 3 Adapting project delivery for innovation, including a Conceptual Phase

not scope alone, but the combination of variable technology maturity, complex regulatory dependencies, and extensive coordination required across engineering disciplines. This stage is about broadening possibilities. Teams explore multiple SAF pathways, such as HEFA, Methanol-to-Jet (MtJ), Alcohol-to-Jet (AtJ), or Fischer-Tropsch (FT), and map flows of feedstock, energy, carbon, water, and value.

Water source

Renewable power

Wood chips

Export

Biomass handling

Water treatment

Wood chip storage

Electrolysis

Gasication

Sub-sea

pipeline

Methanol to jet

Syngas

Methanol synthesis & distillation

Otake

Figure 4 Case study: SAF fuel Pre-FEED

Case study: making innovation bankable through integration strategy The Conceptual Phase has proven vital in emerging sectors like SAF, where diverse feedstocks, technology integration, and policy exposure create complex interdependencies. Here, integration across a multi-step value chain introduces risks and alignment challenges that demand more than engineering discipline. For example, the biomass-to-jet pathway – validated in a recent Pre-FEED (see Figure 4 ) – combines biomass gasification, methanol synthesis, and Methanol-to-Jet upgrading, with renewable hydrogen used to balance syngas composition and improve yields. Although less established than routes like hydroprocessed esters and fatty acids (HEFA), this hybrid bio-power-to-liquids design is emerging as a scalable solution for converting forestry residues, waste biomass, and renewable energy into SAF. What makes it uniquely challenging is

The objective is to identify risks, cost drivers, and opportunities to strengthen returns, while defining clear system boundaries for processing, hydrogen integration, and product export. ASTM certification is a critical milestone in securing investor confidence for SAF projects. Certification confirms that the resulting fuel meets rigorous aviation standards and that the technology pathway fits within established regulatory frameworks. Without ASTM approval, even the most technically promising SAF routes face significant commercial and bankability risk. From concept to feasibility The next step is testing design trade-offs and addressing foundational questions such as: which biomass is the most suitable, and how will key characteristics – including moisture content, bulk density, and chemical composition – vary by sourcing regions and season? What