decarbonising aviation: our clean fuel solution

There is a tendency for governments to place their political and financial chips on the development of future technologies to solve the global climate crisis.

The combination of battery and hydrogen technologies will no doubt accelerate the decarbonisation of road transport, and ultimately, the global transition towards net-zero. However, for air travel, solutions to reduce emissions are yet to be solidified. We use the example of Australia to discuss the aviation sector below.

The Australian aviation sector continues to pollute the atmosphere. In 2019 – before the pandemic – total Australian commercial aviation emissions were estimated to reach 23.8 metric tonnes of CO2-eq or 4.5% of all Australian emissions. The Australian Government recently committed to Net Zero by 2050, leaving the Australian aviation industry with lots of work to do.

Despite advances, battery and hydrogen technology does not apply so well to aviation. Current battery technology is too heavy, lacks energy density, and requires large amounts of rare earth metals such as lithium to be mined in controversial locations across Africa. Similarly, trillions of dollars of capex would be needed to replace the millions of commercial jet engines with batteries. A capex cost, which for most airlines, has become an unsavoury pill to swallow since the pandemic.

Airbus recently stated that “zero-emission hydrogen aircraft will be primarily focused on regional and shorter-range aircraft from 2035”. This means that current and future iterations of highly efficient gas turbines will still be operational as we move towards 2050, especially for long-haul operations. If Australians are to continue to enjoy the positive cultural impacts of international travel, they need a solution that can rapidly decarbonise the existing fleet of airliners.

In the short-medium term, we believe that attention should turn to effective, efficient, and timely solutions for humanity – particularly for the global aviation sector. Solutions that can reduce global carbon emissions today, and do not require 10 or 15 years of resource intensive research and development.

Our solution is Sustainable Aviation Fuel (SAF) derived from waste and algae.

Sustainable Aviation Fuel is a drop-in fuel, which can be blended in a ratio of up to 50% with conventional jet fuel for use in aircraft operating today. First used by the industry in 2008, SAF has powered over 250,000 flights around the world according to Shell. It is a safe, proven fuel, which has the potential to reduce lifecycle emissions by up to 80%, compared with conventional aviation fuel.

While the legal cap on a SAF/Jet Fuel blend is currently capped at 50:50, political mandates for the inclusion of SAF are not as ambitious. For instance, the European Union is seeking to introduce a 2% SAF blend mandate to jet fuel in 2025, moving upwards on a sliding scale to 63% SAF by 2050. The 2% quota is far too low to make a considerable, immediate impact on the current GHG emissions across one of the most well-travelled continents globally. Although this is a good start, political institutions certainly need to go further and faster with legal blending mandates for SAF.

SAF is commonly made from renewable sources such as used cooking oil, municipal waste, and biomass. The global supply of cooking oil and municipal waste is often inconsistent and unreliable. The supply is reliant on human consumption, and the efficiency of the methods used to collect, process, and refine the products. Without a consistency of supply, commercial airlines will always choose the ever-consistent supply of fossil fuels.

An inconsistent, limited supply coupled with rising demand continues to drive SAF prices. SAF is currently retailing for c. $3,000 per metric tonne. Fossil fuel-based aviation fuel currently retails for $740 per metric tonne – 4.3 times cheaper than the price of SAF. Therefore, volumes of SAF remain low, with SAF accounting for less than 0.1% of the aviation fuel market. Without cost parity, SAFs are not going anywhere very quickly.

NBS has solved the ‘inconsistent, limited and expensive’ SAF supply equation. Instead of relying on cooking oils and municipal waste, we grow algae – of which there is more than plenty – on agricultural waste, at a rate of 30 times quicker than is possible for any food crops. As a result, NBS has full control of the supply of our main feedstock – algae – reducing our reliance on external markets and providing our customers with continuity of supply.

Our production method absorbs more emissions than any other SAFs. In production, our crude algae oil absorbs 2.2 metric tonnes of carbon dioxide per 1,000 litres. This means that our SAF has a 90% lower carbon lifecycle than fossil fuels, and 10% lower than oil or waste based SAFs.

To provide context to our supply capabilities, Qantas uses around 5.1 billion litres of fuel per year. Now, that is a huge and pretty much unfeasible amount of cooking oil and municipal waste to purchase as a feedstock for fuel. Just five Infinity Farms, on the other hand, can produce 5.5 billion litres of SAF per annum – equating to over 100% of Qantas’ annual fuel demand.

SAFs will undoubtedly become the main catalysts used in the decarbonisation of air travel. Our Sustainable Aviation Fuel will continue to support the efforts of the global commercial aviation industry reach net-zero before 2050.