Examining the Role of SAF in a Net-Zero Aviation Industry

(Biofuels International) ... Sustainable aviation fuel (SAF) has the potential to cut lifecycle emissions from aviation by up to 80%, making it the largest contributing factor to decarbonising air travel. Biofuels International asks Angela Robledo, business development director, lowcarbon fuels at Worley about the firm’s contributions to this market and the role of SAF in the aviation industry.

Worley’s purpose of delivering a more sustainable world has our people, customers, and planet in mind. SAF is one of the sustainable, lowcarbon solutions that will contribute to a cleaner future. By partnering with our customers, we’re delivering projects to help them to achieve their net-zero targets and that supports a society that has an everincreasing appetite for low-carbon solutions. We transform ideas and concepts into reality. With a portfolio of over 80 low-carbon fuels projects, we design and engineer these types of plants around the world. For instance, we’ve been working for the past two years with Shell to design and build its biofuels facility at Shell’s Energy and Chemicals Park in Rotterdam. Once operating, it will be one of the largest of its kind in Europe, producing 820,000 tonnes of SAF and renewable diesel every year.

The International Air Transport Association (IATA) has estimated the cost to decarbonise the aviation industry at US$1.55 trillion (€1.42 trillion) over the next three decades.

There are seven technology pathways approved by the American Society for Testing and Materials (ASTM) to produce SAF. These can be grouped into five main categories: hydroprocessed esters and fatty acids (HEFA), alcoholto- jet (ATJ), Fischer-Tropsch (FT), hydrothermolysis and microbial conversion.

There are concerns that SAF is sourced from biomass that competes with the food supply chain. How are SAF producers tackling this challenge?

Today, most SAF is produced from fats, oils and greases (FOGs) using the HEFA pathway.

Estimates show that FOGs alone will not be available or cost competitive to supply the entire SAF demand estimated from 2030. By then, we will need to make use of alternative feedstocks, such as municipal solid waste (MSW) and waste carbon for synthetic SAF production.

Today, the cost of production of SAF is significantly higher than fossil-derived jet fuel.

However, we’re seeing a decline in capital costs over time as demonstration plants come online and developers and financiers back larger plants.

A net-zero target for 2050 is aviation’s goal but it might look too far away and consequently, we might not feel a sense of urgency today.

What are the biggest engineering challenges Worley is finding solutions for?

There are several challenges that we’re finding engineering solutions for. For instance, the quality of the biomass waste or municipal solid waste that feeds the process units is critical.

We see innovative opportunities around recycle streams between the gasifier and the partial oxidiser in a FT scheme or around the recycled wastewater streams produced as a by-product.

We think it’s possible for the aviation industry to reach its net-zero targets. In addition to replacing fossil-derived jet fuel, the industry will implement other emissions abatement initiatives such as energy efficiency improvement solutions, carbon capture and storage facilities and will join carbon offsets schemes. Also, world-leading manufacturers are designing hydrogen-fuel and electric aircraft, planned to be in the air by mid-2030s. The production of SAF will still be the key element to achieving a net-zero aviation industry by 2050. We’re witnessing increasing support from governments and regulators that will drive SAF demand.

Reference: 1. iea.org/reports/tracking-aviation-2020 2. iata.org/en/programs/ environment/flynetzero/ 3. whitehouse.gov/briefing-room/ statements-releases/2022/04/12/ fact-sheet-using-homegrownbiofuels- to-address-putins-pricehike- at-the-pump-and-lowercosts- for-american-families/ READ MORE