General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
2026-40978
Description de l'unité
I-Tésé is the research institute in energy economics of the French Alternative Energies and Atomic Energy Commission (CEA), France's largest government-funded research and technology organization[(RTO). Based at the Paris-Saclay and Grenoble sites, I-Tésé aims to develop a systemic view of the economics and sustainability of energy system transformation, an essential perspective for achieving carbon neutrality. Affiliated with the CEA's Energy Division, the Institute brings together experts who conduct research on the techno-economics of energy systems, and supports energy-related studies across various CEA units working on diverse technological pathways (nuclear, PV, hydrogen, storage and flexibility solutions, etc.). The Institute provides foresight and analysis to guide the organization's energy research strategy. It develops models and analytical methods for the CEA's techno-economic community and facilitates the capitalization and sharing of knowledge. Through cross-disciplinary programs and projects, it collaborates with other CEA research institutes as well as with industrial and institutional partners. I-Tésé fosters a vision of the world in which the combination of socio-economic and technological approaches maps out potential pathways to carbon neutrality.
Position description
Category
Environment and climate science
Contract
Internship
Job title
Climate impact of the development of methane and hydrogen pathways towards 2050 H/F
Subject
Mitigating greenhouse gas emissions at the global scale opens the way to alternative energy carriers, among which two gaseous vectors stand out: methane and hydrogen. A particular attention should be paid to the fact that methane is a potent greenhouse gas about 30 times stronger than CO2 and H2 is also a Short-Lived Climate Forcer about 12 times stronger that CO2 (100-year Global Warming Potential, GWP100-basis). While methane is generally regarded as a transition fuel – lower-carbon than coal or oil at the point of combustion, and able to draw on existing transport and storage infrastructure – the role hydrogen might play over the coming decades remains the subject of active research. The internship aims to assess the climate impact of contrasted deployment trajectories for methane and hydrogen towards 2050, by coupling a prospective energy-system model with a reduced-complexity climate model.
Contract duration (months)
6
Job description
The assessment of the climate impact of differentiated deployment pathways for methane and hydrogen through to 2050 will be based on the use of an energy model and a climate model—two tools that play complementary roles:
– with the global energy-system model KiNESYS, the work will build a set of differentiated long-term deployment scenarios spanning a range of socio-economic settings and energy and environmental policy contexts. The technology-rich representation makes it possible to vary the scale and timing of methane and hydrogen use, the production mix (grey, blue, green), and the associated infrastructure, and to derive consistent emissions trajectories for the carriers and their value chains;
– these trajectories will then be fed into the reduced-complexity climate model ACC2 (LSCE). ACC2 calculates global-mean temperature changes based on emissions for a variety of greenhouse gases – such as CO2 and methane – and related gases that can indirectly affect the climate via chemical reactions – such as pollutants and hydrogen. ACC2 has been used for various policy applications and assessments. It accounts for major processes in the global Earth system, comprising (i) carbon cycle, (ii) atmospheric chemistry, and (iii) physical climate modules. The atmospheric chemistry module is highly parameterized and based on sensitivity analyzes using several Chemistry Transport Models, representing interactions between methane, hydroxyl radical, ozone, and pollutants.
A central methodological step is the consistent representation of methane and hydrogen leakage across the two models, and the integration of hydrogen’s indirect forcing into the climate component. The expected outcome is a differentiated assessment of how a gas economy affects warming, together with an analysis of the sensitivity of the results to leakage rates, to the green / blue / grey production mix, and to the chosen time horizon – elements that are decisive for distinguishing scenarios that deliver a clear climate benefit from those that do not.
Work programme
1. Literature review on the direct and indirect climate impacts of methane and hydrogen and on leakage rates along the value chains;
2. Completion of the KiNESYS database with methane and hydrogen leakage rates;
3. Design of contrasted deployment scenarios with KiNESYS (with I-Tésé team);
4. Estimation of hydrogen impacts on climate using ACC2 and emission metrics (with LSCE team);
5. Impact assessment and sensitivity analysis (all).
Methods / Means
Python, GAMS
Applicant Profile
– Engineering or university student (Master’s / final year);
– Background in energy / environmental economics or in climate science;
– Skills in climate modelling and/or prospective (scenario) modelling; comfort with quantitative work (Python, GAMS, data handling).
Position location
Site
Saclay
Job location
France, Ile-de-France
Location
Saclay
Candidate criteria
Prepared diploma
Bac+5 - Master 2
Recommended training
energy / environmental economics or in climate science
Requester
Position start date
01/09/2026