Bio-based feedstock availability for SAF will likely only be sufficient to supply 50% of the SAF required to meet IATA’s net zero carbon by 2050 target, concludes an ICF report prepared for the second edition of the cross-industry Air Transport Action Group’s Waypoint 2050 report. The other 50% of projected fuel demand by 2050 will have to come from Power-to-Liquid (PtL) technology, finds ICF. Although HEFA SAF is fully commercial and currently supplies most SAF, the availability of sustainable feedstocks will limit its overall contribution to SAF volumes to less than 10% by 2050. The Waypoint 2050 report estimates that 330-445 million tonnes of SAF, alongside technological and operational improvements, will be required for the global aviation industry to achieve net zero carbon emissions by 2050, reports Susan van Dyk. Speaking at the recent 2021 ATAG Global Sustainable Aviation Forum, Kata Cserep, ICF Global Managing Director of Aviation, said the ICF study set out to answer three simple questions: is there enough feedstock to produce the SAF required, how much will it cost, and where will it come from?
The size of the challenge is significant, said Cserep, and about 400 million tonnes (around 500 billion litres) of SAF will be required by 2050, representing an increase of 8000% from last year’s SAF production. But the ICF report shows that this can be done, she stated, mapping the pathway to achieve the projected quantities of SAF needed by 2050, including feedstock availability, number of production facilities and the total investment cost that will be required.
The projected volume of SAF by 2050 will depend on the extent that technologies such as hydrogen and electric aircraft can deliver emission reductions in the sector. Between 5,000 and 7,000 SAF production facilities will be required to deliver these volumes at a total infrastructure investment cost of $1-1.5 trillion dollars over 30 years. Put into perspective, explained Cserep, the annual investment cost will only be about 6% of historical annual investment in the oil and gas sector.
The regional distribution of feedstocks and SAF production forms a key part of the report as the nature of the feedstock dictates that production will take place closer to the sources of feedstock, making SAF production a more distributed energy source through all regions, unlike oil and gas which is highly concentrated in a few countries. The benefits of SAF also lie in its ability to create jobs, with 23 people employed today for every $1 million invested in bioenergy. SAF production at these levels will be able to sustain up to 14 million jobs in the collection and processing of the feedstock, with 90% of the jobs across the supply chain, said Cserep.
Feedstock availability is a prerequisite for SAF production. The WEF-CST report published earlier this year also analysed feedstock availability for SAF production, but did not take competing uses of feedstocks for bioenergy and other applications into account, according to Alastair Blanshard, Senior Manager and Sustainable Aviation Lead at ICF and the lead author on the ICF study.
As a result, the WEF-CST analysis concluded feedstock availability was not a limitation for SAF production and that enough biogenic feedstocks were available worldwide to produce about 500 million tonnes (621 billion litres) of SAF by 2050. In contrast, the ICF study built on bioenergy feedstock analysis by the IEA and Energy Transitions Commission to calculate that biogenic feedstocks will only be able to deliver about half of SAF requirements by 2050. Feedstocks assessed in the ICF report were limited based on sustainability and excluded crops such as vegetable oils, corn, sugarcane and others in keeping with the sector’s sustainability goals, explained Blanchard.
Under the most aggressive SAF deployment scenario, SAF can be delivered in three main phases (see graph below), Cserep told the ATAG Forum. The HEFA (Hydroprocessed Esters and Fatty Acids) process, which uses waste lipids, is the only commercial pathway today and is in a rapid scale-up phase. However, HEFA will become feedstock constrained, limiting it to less than 10% of total SAF production by 2050. The next two decades will be dominated by advanced feedstocks, such as municipal solid waste (MSW) and forest residues, and using technologies such as alcohol-to-jet (AtJ), Fischer-Tropsch (FT) and others. PtL technology is expected to start producing significant volumes after 2035. Although this technology does not require biogenic feedstocks, Blanshard estimates it will require eight TWh of renewable electricity to deliver projected 2050 volumes, which alongside electricity to charge battery and hybrid aircraft, is likely to be just under 10% of all renewable electricity.
The high cost of SAF is considered a significant obstacle for airlines. “The perception of cost is always the first stumbling block,” commented Blanshard. However, the ICF analysis demonstrates SAF production prices will decrease in all feedstock and technology combinations, driven by technology advances, economies of scale and increased carbon efficiency. When including the value of carbon, the fuel price is expected to be between $760-$900 per tonne of SAF by 2050, well within the historical range of fossil fuel.
The report did not address the policies required to achieve this level of SAF production, and analysis was based on a simplified policy environment with a global price on carbon, said Blanshard. Most thinking today is unfortunately based on volumes of fuel, rather than percentage carbon abated, he stated.
Significant policy developments have been taking place recently, including proposals for SAF blending mandates in Europe and the UK, and a SAF blenders tax credit in the USA. The proposed EU mandate is a volumetric mandate, whereas the UK mandate proposal prioritises carbon emissions savings through a GHG emissions scheme issuing credits proportional to the kilograms of CO2e saved. The US blenders tax credit and the California Low Carbon Fuel Standard similarly rewards greater carbon intensity reductions, spurring many companies in the US to target net zero SAF and even negative carbon intensity through measures such renewable electricity, green hydrogen and carbon capture and storage.
While the ICF report capped carbon intensity at a 100% reduction, negative carbon intensity SAF should be able to reduce the volumes required by 2050.
Top image: Shell