Carbon offsets rather than biofuels will be the main mechanism for reducing net greenhouse gas emissions in the fast-growing international aviation sector, according to a briefing paper released earlier this month by the International Council on Clean Transportation (ICCT).
The paper assesses likely carbon reduction initiatives under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), the International Civil Aviation Organization (ICAO)’s much-touted market-based mechanism for addressing aviation emissions.
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For Canadian and U.S. carriers, “the high expense of AJFs [alternative jet fuels] relative to the low projected cost of offsets in the near future makes it unlikely that CORSIA alone will drive high levels of fuel switching,” ICCT concludes. “While North America possesses a relatively high availability of the feedstocks to produce sustainable, low-carbon AJF than do other world regions, the fuel pathways remain constrained by feedstock availability, cost, and time it would take to commercialize an advanced AJF industry.”
To shift that assessment, ICCT adds, “the U.S. and Canada would likely need to implement supplementary policies that specifically incentivize AJF production, along with full life-cycle emissions accounting to ensure that GHG targets are met.”
In its own analysis of the report, Biofuels Digest points to design features of CORSIA that point the system toward less expensive carbon offsets, to the detriment of aviation biofuel development.
Based on projected demand growth and fuel efficiency gains, Canadian and U.S. international carriers would have to offset 250 megatonnes of CO2 through 2035, notes editor Jim Lane. That would translate into 50 billion gallons of a biofuel that cut emissions by 50%—in other words, 3.3 billion gallons beginning in 2020, or five billion beginning in 2025.
“The math outlines the challenge,” Lane writes. “Right now, advanced biofuels refineries that can make jet fuel are planned in the 10- to 75-million-gallon-per-year range, Wall Street isn’t exactly falling over itself to invest in them, and airlines have taken a very proactive position on signaling intent to purchase, so long as it doesn’t cost any more in dollar terms. Minimally, we’re looking at 35 refineries, maybe more. Needed soon.”
But Lane lists a series of economic factors—from competing demands for feedstock, to land tenure rules for biofuels—that will likely perpetuate the mismatch between supply and potential demand, rather than solving it.
Earlier this month, a feature article in Politico made a similar case: While biofuels may be the best decarbonization opportunity for international aviation, “the industry isn’t likely to adapt to them for several decades without more of a nudge,” wrote reporter Sara Stefanini.
“At least in the medium term, probably 20 to 30 years, we don’t see a viable option apart from using a liquid hydrocarbon fuel,” said Robert Boyd, manager of environment and alternative fuels at the International Air Transport Association (IATA). While biofuels could cut the industry’s carbon dioxide emissions by 80%, and are technically ready for prime time, Boyd said airlines would need stronger incentives to conduct research and reduce costs.
“Given we’re seeing quite rapid technological advances in battery technology and other methods for the ground-based sector to decarbonize, we feel there’s merit to incentivizing producers to supply aviation with renewable fuel,” he said.
Politico traces the European Commission debate over clean transport fuels, with emphasis shifting away from food crops in favour of woody crops, farm residues, waste, and other organic materials as potential feedstocks. A Commission proposal tabled last November would set a clean fuel target of 6.8% by 2030 for the transport sector as a whole, with at least 3.6% coming from advanced biofuels, and “every unit of biofuel that goes toward an aircraft or ship would be would be worth 1.2 units, making it an attractive way to meet the target,” Stefanini notes.
“The aviation industry likes this idea, but argues it’s not enough. Not only does the sector have fewer options for clean energy sources, but its strict safety standards limit the types of biofuels it can use,” she writes. “The answer, according to aviation and biofuels industry sources, is to give aviation an even greater incentive to account for its more limited options compared to the maritime industry—around 2.0 [units], according to one source.”