Deployment strategy for energy infrastructures on a regional scale: an economic and environmental optimisation approach

The general context is "Design and optimisation of multi-vector energy systems on a territorial scale".
More specifically, the aim is to develop new methods for studying trajectories for reducing the overall environmental impact (underlying LCA) of a territory while controlling costs in various applications, for example:
- Opportunity to develop infrastructures (e.g. H2 network, or heat network) to enhance decarbonisation, by expanding new uses of energy where these infrastructures exist or will exist, while reducing the overall environmental impact for given uses.
- Based on these studies, study the impact of centralising or decentralising production and consumption resources,
- Taking into account the long-term dynamic of investments, with the compromise of renovating/replacing installations at a given moment, in order to reduce the overall environmental impact for given uses.
Possible applications for hydrogen infrastructures have been identified or are being identified

Raw earth soil, an age-old material with new emerging uses

Raw earth materials, which have found multiple uses for millennia, now offer considerable potential for helping to adapt to the changing climate, thanks to their natural ability to regulate heat and water, as well as their low-CO2 production and shaping. However, scientific advances are still needed to get a more precise understanding of these materials, up to the nanometric scale.

This thesis focuses on the link between the mechanical properties of raw earth soil materials and their nanostructure, emphasizing the roles of confined water, ions and organic substances. Two approaches, based on the expertise on nanoporous media developed at CEA, Saclay and Marcoule, will be followed: the analysis of old materials using spectroscopic and radiation scattering methods, and the development of a screening protocol to identify physicochemical parameters important for durability. This research, which ultimately aims to optimize the formulation of raw earth materials, will be carried out in collaboration with architects specialists in the field.

Advanced modeling of Gas Diffusion Layers for Fuel Cells: ink impregnation and drying, 3D phase distribution, and effective properties

In the frame of advanced H2 solutions for the energy transition, the Proton Exchange Membrane Fuel Cell (PEMFC) is a relevant solution for the production of low-carbon electrical energy. The European Project DECODE proposes to develop a fully digital chain of design tools, including raw material properties, manufacturing and assembly of the different components, to predict the performance of such ‘virtual’ stack. This will help reducing the development cost and time of improved materials/components suitable for different applications in the future.
The component considered in this thesis is the Gas Diffusion Layer (GDL), which is a combination of a fibrous microporous substrate and of a micro/nano porous layer (MPL for microporous layer). The work will be split into different steps: a) based on (real or virtual) 3D images of the substrate, simulation of the hydrophobic and MPL coating and drying to derive the 3D distribution of the components (fibers, hydrophobicity and MPL); b) simulation of single and two-phase transport properties of the GDL to supply inputs to upper scale performance models; c) sensitivity analysis of the main manufacturing processes (ink properties, drying parameters…)