by Mark Carter
But don’t be misled. These new fuels are not sustainable. Nowhere are the tonnes of CO2 emissions they can reduce or need to reduce stated. Their use will therefore greenwash growing fossil fuel emissions from Australian aviation.
‘Sustainable’ Aviation Fuels
‘Sustainable’ Aviation Fuels come either as biofuels or as e-fuels. Biofuels are hydrocarbons made from bio-crops (such as sugar, corn and canola) and bio-waste (such as pig fats or tallow, and oils including soybean oil and used cooking oil). E-fuel is a synthetic hydrocarbon made from hydrogen (extracted from water) and carbon (sourced from industrial production waste streams such as ammonia and ethanol production, or from CO2 produced via biomass combustion, or from Direct Air Capture technologies) using electricity.
They ain’t sustainable
Deployment of SAF will be damaging, very expensive, too slow to support timely reductions in aviation emissions let alone making them ‘net zero by 2050’, and require a profligate use of renewable energy and tax payer funds. The US Institute for Policy Studies says “There is currently no realistic or scalable alternative to kerosene-based fuels that would meet current aviation needs, let alone the industry’s projections of future growth.”
Too damaging: Monoculture SAF feedstock cropping damages biodiversity, takes land from food cropping, and prevents nature-based carbon sequestration. Australian IPCC climate scientist Brendan Mackey says “Large-scale SAF deployment could undermine global climate efforts.”
Very expensive: SAF production costs are two to seven times higher than those for jet diesel. Airlines will incur the cost of modifying aircraft fuelling systems to burn 100% SAF. Aengus Kelly, CEO of AerCap, the world’s number one aircraft leasing company, says “If governments want airlines to burn sustainable aviation fuel, they’re going to need to devote extraordinary sums of taxpayers’ money to make it happen.”
Too slow: Low demand for, and poor supply of SAF feedstock are likely to prevent the manufacture in Australia of enough SAF to meet total fuel demand — even by 2050. Qantas has a target to replace only 10% of its jet diesel fuel with SAF by 2030, and by 2050 almost half the fuel it burns will still be jet diesel. Federal Infrastructure and Transport Minister, Catherine King, has spruiked in parliament, canola and tallow as new low carbon liquid fuel feedstocks, despite a CSIRO/Boeing study suggesting they could replace at most 11% of domestic jet fuel demand in 2025. The UK government projects e-fuel providing only 3.5% of Britain’s aviation fuel demand by 2040. To manufacture enough biofuel to provide for Australia’s aviation needs would likely require the conversion to feedstock cropping of an area in the order of that needed to grow Australia’s total wheat crop — around 11 million hectares. Willie Walsh, Director-General of the International Air Transport Association, says “We believe that 5% of SAF in 2030 is exceedingly ambitious [and] won’t be achieved everywhere in the world.” And, by abandoning its 2030 emissions target recently, Air New Zealand would appear to agree.
Inefficient use of renewable electricity: Aviation’s reliance on e-fuels in the long term — to reach net zero 2050 — could require 9% of global renewable electricity in 2050. E-fuel’s demand for renewable electricity at this level would likely deprive other sectors of renewables that could deliver greater decarbonising.
Inefficient use of financial resources: The $1.7 billion Australian taxpayer investment in low carbon liquid fuels that deliver minimal emissions cuts, on top the existing annual $1.6 billion concessional fuel tax subsidy of the aviation industry, takes funding away from greater emissions reductions in other sectors.
Burning SAF won’t reduce fossil fuel emissions
Even if these constraints on the supply of SAF did not exist, burning SAF will not cut fossil fuel emissions from Australian aviation, despite its promotion by the government, industry and media as ‘sustainable’, and ‘ecofriendly’.
The same amount of CO2 is emitted burning biofuels as jet diesel, not less. Graham Warwick, Aviation Week executive editor for technology, says “The big problem with bio-based SAF is you’re not reducing emissions … you’re still pumping CO2 out of the tailpipe of the engine.”
CO2 emissions from biofuels can only be said to be less than those from jet diesel if we enter a time-warp. Here the CO2 drawn down months or years earlier in growing the biofuel feedstock, is subtracted from the in-flight CO2 emissions. Graham Warwick, Aviation Week executive editor for technology says of the industry’s 80% emissions reduction claim for SAF, that “It’s not a physical reduction, it’s an accounting reduction.”
In reality CO2 emissions reductions are half those often claimed for SAF, since biofuels and e-fuel must be blended 50:50 with fossil jet diesel to be used in the existing global airline fleet.
Just like with fossil jet diesel, burning biofuels and e-fuels create non-CO2 emissions that are twice as warming as CO2 alone.
With the number of flights growing 4% annually, any marginal reduction in emissions actually resulting from burning SAF will be more than countered by the extra emissions from increased flights.
The IPCC says “limiting warming to around 1.5°C requires global greenhouse gas emissions to peak before 2025 at the latest, and be reduced by 43% by 2030”. It is evident that Australian aviation emissions cannot align with this Net Zero 2050 pathway.
Climate context
But even if Australian aviation emissions could align with a Net zero emissions by 2050 pathway, that won’t prevent 2ºC of warming, let alone 1.5ºC.
On the net zero emissions by 2050 path that our government is pursuing, warming will pass 2ºC well before 2050. Continuing emissions, aviation included, have already pushed global warming just short of the 1.5ºC Paris limit. For an acceptable likelihood of preventing warming of 2ºC, and the civilisation-devastating consequences of the multiple tipping points thereby triggered, aviation emissions, like all emissions, need to be cut to near absolute zero at emergency speed.
But that ain’t all. The CO2 already in the atmosphere has made our climate unsafe. At 427 parts per million (ppm), it previously raised global sea levels 10 metres and pushed warming to 3ºC. To have a chance of returning warming to a safe level (below 1ºC), rapid sequestration of carbon is needed to cut the 427ppm to under 350ppm. So using carbon drawdown or sequestration to excuse new emissions — the very basis of the SAF time warp scam — is clearly not on.
Cutting aviation emissions effectively
The only effective way currently available for emissions reductions from aviation to align with the 2015 Paris Agreement limits, is through a dramatic reduction in the number flights — an action not seriously addressed in the government’s transport emissions reduction roadmap.
Government policies that would enable this action include:
- Capping aviation fossil fuel emissions. A cap could be managed by redefining airport capacity — currently defined as the total number of flights allowable — as the total allowable emissions from departing flights. The cap could be airport specific or a total for all Australian airports. The cap would reduce each year to near zero by 2030. Renewables powered short haul flights would not be constrained.
- Mandating the counting of all emissions in annual Australian aviation emissions totals, including those from departing international flights, Scope 3 emissions, and non-CO2 emissions.
- Banning the use of carbon offsets in the calculation of aviation emissions.
- Halting taxpayer funding of biofuels.
- Ending aviation subsidies by raising the aviation fuel excise tax 900% to equal that on other transport fuels.
Halting the promotion of aviation emissions by banning airline advertising and frequent flyer schemes, by mandating tickets include per passenger emissions for that flight, by penalising greenwashing, and by halting airport expansions.
