Extended paper

Extended paper#

Numerical optimization of aviation decarbonization scenarios: balancing traffic and emissions with maturing energy carriers and aircraft technology

Ian Costa-Alves1,2, Nicolas Gourdain1, François Gallard2, Anne Gazaix2, Yri Amandine Kambiri1,3, Thierry Druot3

1 Aerodynamics, Energetics and Propulsion Department, ISAE-SUPAERO, Toulouse, France — 2 Multidisciplinary Optimization Competence Center, IRT Saint Exupéry, Toulouse, France — 3 Conceptual Airplane Design and Operations, ENAC, Toulouse, France

Note

This section is the web version of the companion paper, published as: Costa-Alves I., Gourdain N., Gallard F., Gazaix A., Kambiri Y.-A., Druot T. (2026). Numerical optimization of aviation decarbonization scenarios: balancing traffic and emissions with maturing energy carriers and aircraft technology. Applied Energy, 412, 127631. doi:10.1016/j.apenergy.2026.127631. The LaTeX sources are kept in the repository under docs/paper/latex_src/.

Abstract#

Despite being considered a hard-to-abate sector, aviation’s emissions will play an important role in long-term climate mitigation of transportation. The introduction of low-carbon energy carriers and the deployment of new aircraft in the current fleet are modeled as technology-centered decarbonization policies, while supply constraints in targeted market segments are modeled as demand-side policies. Shared Socioeconomic Pathways (SSPs) are used to estimate trend-mitigation traffic demand and to limit the sectoral consumption of electricity and biomass. Mitigation scenarios are formulated as optimization problems, and three applications are demonstrated: no-policy baselines, single-policy optimization, and scenario-robust policies. Results show that the choice of energy carrier is highly dependent on assumptions regarding aircraft technology and the background energy system. Across all SSP-based scenarios, emissions peak by around 2040, but achieving alignment with the Paris Agreement requires either targeted demand management or additional low-carbon energy supply. The use of gradient-based optimization within a multidisciplinary framework enables the efficient resolution of these nonlinear, high-dimensional problems while reducing implementation effort.

Highlights#

  • Optimization framework links SSP scenarios with detailed aircraft technology;

  • Fleet replacement and demand saturation leads to emissions peak around 2040;

  • Impact of alternative aircraft requires extending analysis beyond 2050;

  • Respecting +2°C carbon budgets requires demand caps or extra energy availability;

  • Policy optimization was prohibitive without speedups from numerical methodology.

Keywords: Multidisciplinary Optimization; Low-carbon fuels; Aircraft design; Integrated Assessment Models; Shared Socioeconomic Pathways

../_images/graphical_abstract.png

Fig. 1 Graphical abstract.#

Acronyms#

AD

Automatic Differentiation

ASK

Available Seat Kilometers

ATJ

Alcohol-to-Jet

BtL

Biomass-to-Liquid

EIS

Entry-Into-Service

FD

Finite Differences

FT

Fischer-Tropsch

GAM

Generic Airplane Model

GDP

Gross Domestic Product

HEFA

Hydroprocessed Esters and Fatty Acids

IAM

Integrated Assessment Model

IPCC

Intergovernmental Panel on Climate Change

JIT

Just-In-Time

LH2

Liquid hydrogen

MDO

Multidisciplinary Optimization

PtL

Power-to-Liquid

RCP

Representative Concentration Pathway

RPK

Revenue Passenger Kilometers

SAF

Sustainable Aviation Fuel

SSP

Shared Socioeconomic Pathways

TLAR

Top Level Aircraft Requirements

The mathematical symbols used throughout the models are collected in the nomenclature.

Code availability#

All the scripts and data required to reproduce the results from this work are openly available in iancostalves/noads.

Acknowledgements#

Gratitude is extended to the Conceptual Airplane Design and Operations (CADO) team at École Nationale de l’Aviation Civile (ENAC), to the Aviation, Climate, Environment (ACE) group at ISAE-SUPAERO, and to the Institute for Sustainable Aviation (ISA) for their support, assistance, and fruitful discussions. The Generic Aircraft Design Model (GAM), provided by the CADO team, was essential for enabling modeling and analysis of alternative aircraft designs. The AeroMAPS platform, developped by ISAE-SUPAERO and ISA, was reponsible for laying the groundwork upon which this research was built. Special thanks to Pascal Roches, Nicolas Monrolin, Thomas Planès, Scott Delbecq, Antoine Salgas, Florian Simatos, Laurent Joly, and Xavier Carbonneau for their sharp insights, support, and collaboration.

Also, the authors thank the Multidisciplinary Optimization Competence Center at IRT Saint Exupéry, for their availability and support with the methodological developments that preceded this research. Special thanks to Matthias De Lozzo, and Antoine Dechaume for their aid with repository maintenance and thorough code reviews.

CRediT authorship contribution statement#

Ian Costa-Alves: Writing – original draft, Writing – review & editing, Conceptualization, Data curation, Investigation, Methodology, Software, Validation, Visualization.

Nicolas Gourdain: Writing – original draft, Writing – review & editing, Conceptualization, Methodology, Funding acquisition, Project administration, Supervision.

François Gallard: Writing – original draft, Writing – review & editing, Conceptualization, Methodology, Software, Supervision.

Anne Gazaix: Writing – review & editing, Conceptualization, Funding acquisition, Project administration, Supervision.

Yri-Amandine Kambiri: Writing – review & editing, Software, Validation.

Thierry Druot: Writing – review & editing, Conceptualization, Software, Supervision, Validation.

Funding sources#

This work was supported by the Occitania region, ISAE-SUPAERO, and IRT Saint Exupéry.