Jet Fuels Neutralized With DACCS More Cost-Efficient Than SAF, New Analysis Shows

Jet Fuels Neutralized With DACCS More Cost-Efficient Than SAF, New Analysis Shows - Carbon Herald
Source: Ip-sutdio via Shutterstock

As sustainable aviation fuels are becoming a significant part of the decarbonization strategies of the sector, a new analysis is looking into their cost efficiency, revealing interesting facts. According to research by Robert Höglund (carbon removal expert) and Sandilya Sivaraju (Chemical Engineer from Upenn with a strong background in researching electrofuels), continued fossil jet fuel use, neutralized with permanent carbon removal, is likely to be a more cost and resource-efficient alternative for aviation than electrofuels. 

The analysis published in Marginal Carbon compares the costs of SAF with the cost of continued use of fossil jet fuel whose emissions from burning the fuel has been removed via direct air capture and storage (DACCS). 

The calculations show that a net zero flight in 2050 using SAF comes at $645 while a flight using jet fuel with carbon removal comes at around $433. The higher competitiveness of the jet fuel + DACCS scenario stems from the large energy requirements of electrofuels – seven times higher than the BAU+DACCS scenario.

Credit: Marginal Carbon

The analysis also explores the prices of bio-jet fuels. The results show that they are also cheaper than electrofuels. The cheapest HEFA (Hydroprocessed Esters and Fatty Acids) bio-fuel is lower in price compared to the BAU+DACCS approach in many scenarios, however, it is not able to meet the demand from the aviation sector to replace traditional jet fuel due to feedstock constraints. 

Relevant: New Report Charts A Path For Carbon Removal And Emission Reductions

Building out the needed zero emissions electricity capacity for the production of electrofuels turns out to be the largest constraint. The analysis shows that even with increased efficiency, electrofuels would require 9,000-10,500 kWh per tonne of CO2. Replacing just a third of current aviation fuel with electrofuels would demand over 2500 TWh per year – equivalent to 10% of global electricity consumption. For comparison, neutralizing these emissions via DACCS would require only 410 TWh.

“Emission reductions stemming from expensive alternative fuels with huge energy needs are not inherently better than carbon removal,” the research highlights. 

The analysis leads to the conclusion that certain industries like aviation might require a higher percentage of emissions to be neutralized via carbon dioxide removal than what the general SBTi net zero targets suggest, as they recommend CDR compensation to only up to 10% of emissions. 

Relevant: Releases A Carbon Removals Purchase Calculator

Suggestions are put forward for decision makers to consider cost-efficiency of different alternatives when making plans for net zero aviation. Three concrete policy proposals are put forward:

  • To include permanent carbon removal into the aviation credit scheme CORSIA, demanding it to reach 100% of credits by 2050. 
  • To develop specific SBTI sector targets for aviation.
  • To include permanent CDR credits in the EU SAF mandates.
1 comment
  1. If you were to actually use science to determine the aforementioned ‘science based targets’ you will see that the energy balance of DACCS is terrible – it uses over 2.5MWh of energy to extract 1 tonne of carbon from the atmosphere. If this 2,5MWh energy is produced from renewables then this capacity is much better utilised to directly replace fossil energy sources and will achieve greater reductions in atmospheric CO2 than using the same energy to suck CO2 back out of the air after its been released. Also the widespread deployment of DACCS is highly unlikely, since the required energy, infrastructure and poor efficiency of extraction mean that massive amounts of capacity would be required to even make a small dent in global emissions.

    Therefore the comparison of SAF with DACCS is a moot point. SAF will not be able to meet the full challenge of decarbonising aviation, but DACCS is also not a viable route. Renewable energy globally should be used to directly reduce the carbon emissions of the energy sector as a whole, not co-opted to highly energy inefficient processes such as DACCS or production of e-fuels. Stop looking at siloed emissions from narrowly defined sectors and use the available technology where it can have the most impact on reducing overall global carbon emissions, don’t waste it by directing it towards satisfying the marketing requirements of one sector.

Leave a Reply

Your email address will not be published. Required fields are marked *

Related Posts
Translate »