Aviation Decarbonizaton Forum Presentations, February 2019

On February 12, 2019, at the Hotel AC Montreal, ICSA hosted the Aviation Decarbonization Forum—an exclusive event for ICAO Council members, permanent representatives, and their advisers to receive the most comprehensive, up-to-date information about how aviation can reduce its climate impact. The event followed the Chatham House Rule.

The key insights of the event were the following:

Target setting to address aviation’s climate impact

  • There are clear benefits for policy makers to aim at preventing warming above 1.5°C versus 2°C.
  • There is limited potential for offsetting given that there will be little opportunity to outsource emissions reductions to other sectors in a more carbon constrained world.
  • When policy makers set a long-term emissions pathway for a sector (like aviation), a bottom-up or top-down approach can be taken. They can also be taken together.
  • In the analysis presented by Dr. Cames, the ATAG 2050 target would lead to emissions 29% higher than they need to be for aviation to align itself with a 2°C pathway (the RCP2.6 pathway). Thus, this target is not aligned with the temperature goals of the Paris Agreement.
  • Contrary to much of the media coverage of the IMO GHG strategy, it not only has a long-term 2050 target (70% lower CO2 intensity from 2008 levels by 2050) but also a mid-term target (40% lower CO2 intensity from 2008 levels by 2030. This could be instructive for how ICAO might think about setting a long-term goal.

 

Developing more efficient aircraft

  • Among transport modes, aviation is uniquely sensitive to weight effects, limiting the solution space.
  • Baseline new aircraft fuel efficiency improvement is 1 to 1.5% per year, plus operational efficiencies on top. The challenge is to accelerate the 2% per year current trend to 3%+ recognizing the need to protect safety, certification delay, high risk of investment failure, among others.
  • Electric aircraft are coming for general aviation and regional flights. Hybrid electrics are more likely for most commercial flights. Drop-in alternative fuels for the existing fleet will also be important for the sector.
  • Further efficiency gains through advanced configurations–blended wing body, truss based wing, distributed propulsion, etc.–are important but will require substantial R&D support. Some approaches could be paired to hydrogen. Smaller jumps–folding wingtips, re-engines with geared turbofan, etc.–are already underway.
  • There is no technology silver bullet: We need an “all of the above” approach for more GHG efficient aviation. This includes faster incremental improvements, much more R&D, accelerated fleet renewal, “drop-in” alternative fuels, better procedures (e.g. climate optimized routing), compensation (CORSIA and beyond), stronger incentives (legislation + societal pressure), and limiting and even reversing growth, preferably soon.

 

Sustainable alternative fuels

  • Dr. Malins noted that reaching 100% alternative fuels for aviation will be massively challenging and costly.
  • Dr. Malins noted that CORSIA will create very small additional incentive for SAF usage by airlines.

Bio-based

  • The Energy Transitions Commission’s view that waste is the only sustainable source of biofuel feedstock.
  • Panelists noted that biofuels for aviation or any sector is certainly not an efficient use of biomass on the whole; however, one panelist pointed out that there are many factors at play in determining whether a biofuel can be or is “sustainable” including location, water constraints, etc.

Power-to-liquids (PtL)

  • PtL could cost more than two times that if it is coming from air capture. But when one considers a full accounting of costs and considers the impacts of climate change on human societies.
  • PtL has some clear environmental sustainability advantages over biofuels–namely a considerably lower water footprint and lower land demand by a (conservatively estimated) factor of eight.
  • Fast action is needed to realize the promise of PtL. No other solution would use a good amount of existing infrastructure that employs sustainable renewables for air transport.
  • Business aviation may be where we start with PtL. Remote airports might potentially be good candidates to supply with this fuel, given costs of transporting fuel to these places.
  • We also might think about more pilots and investments in areas where renewable electricity is cheap–e.g. 2 cents/kWh in Mexico. Dubai could be another place.  
  • We need to pay more and invest in this technology.
  • As for policy, perhaps a feed-in tariff scheme could work to encourage production.

 

Non-CO2 effects

  • Dr. Grewe noted that while aerosol impact on clouds is still uncertain, we can still calculate that, overall, aviation contributes about 5% of manmade global warming. More than 50% of this warming is due to CO2 and some of it due to other non-CO2 climate forcers.
  • Optimizing flight paths to avoid climate-sensitive areas could substantially reduce the climate impact of aviation at low cost increase, even as this will have some impact on air traffic patterns.
  • New methods are almost here that will help policy makers and others account for non-CO2 effects on a flight-by-flight basis and converting these into a CO2 equivalent.

 

Please see below for a full agenda of the event, a non-attributional summary of the event, and the speakers’ presentations:

Full agenda

Summary of the 2019 Aviation Decarbonization Forum

Speaker presentations:

Overview of the IPCC Special Report Global Warming of 1.5°C (Dr. Heleen de Coninck, Associate Professor, Innovation Studies, Environmental Science Department, Radboud University, Faculty of Science)

The Global Decarbonization Challenge and Aviation within It: Where Are We Now, Where are we going? What should aviation’s fair share of these emissions reductions be and how does this compare to ATAG’s 2050 aspirational target? (Dr. Martin Cames, Head of Energy & Climate Division, Oko Insitut)

Unlocking greater near-term efficiency, while transitioning to the next generation of planes “There is no quick fix” (Dr. Joris Melkert, TU Delft, Aerospace Engineering)

Alternative Fuels: Flightpath to 2050? (Dr. Chris Malins, Cerulogy)

Why We Need Power-to-Liquid-Based Fuel Solutions for a Sustainable Future of Aviation
(Dr. Harry Lehmann, General Director, Environmental Planning and Sustainability Strategies, Federal Environment Agency (UBA), Germany)

Addressing non-CO2 effects of aviation (Dr. Volker Grewe, Professor, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen and Chair for Climate Effects of Aviation, Delft University of Technology.)

“Mission Possible: Reaching net-zero for aviation (& other hard to abate sectors) by mid-Century”, (presented by Adam Klauber, representing the Energy Transitions Commission (ETC)