How EPFL will make the most of its carbon emissions

By supporting a large-scale research project for carbon capture, utilization and storage, EPFL will shrink its carbon footprint while giving a boost to emerging technology.
The EPFL demonstrator aims to capture CO2 emissions at source and value them. © iStock

Truly sustainable systems are those that are win-win, based on a long-term circular economy approach. Such systems could, for example, cut CO2 emissions by capturing it at the source and then reusing it to produce energy carriers, commodity chemicals for value-added products, or building materials, or storing it underground. These types of systems don’t yet exist – but EPFL has all the skills to make them happen. That's why the School’s Solutions4Sustainability initiative is supporting the creation of a demonstrator in Valais and the development of technology that’s ready to be scaled up.

To achieve carbon neutrality and thus mitigate climate disruption, we must reduce the amount of CO2 in the atmosphere. We can curtail carbon emissions by making greater use of renewable energy, but we also need to "clean" the air of the gigatons of CO2 that have already been emitted. Here, the solution lies in carbon capture, utilization and storage (CCUS) systems. Technology is emerging in all three of these areas, and it’ll be essential to give it a boost so that new systems can be put to industrial and economically viable use.

That’s the goal of SusEcoCCUS – an EPFL project that aims to create a circular, sustainable economy leveraging CCUS. In concrete terms, engineers will build a pilot-scale demonstrator capable of capturing and processing up to one metric ton of CO2 per day. The project kicked off last fall and will be funded to the tune of CHF 9 million over 6 years. It involves 11 EPFL research groups spread across three campuses (Valais, Lausanne, and Neuchâtel) and three schools (School of Basic Sciences, School of Engineering, and School of Architecture, Civil and Environmental Engineering).

The proposed CCUS demonstrator at the site of Enevi waste incineration plant near the EPFL Valais campus. 2024 EPFL/MCV CC-BY-SA 4.0

The first aspect of the project is carbon capture. The idea is to collect CO2 at the source – in this case at the Enevi incineration plant in Uvrier, Valais. Starting this year, the plant will heat EPFL Valais-Wallis’ I17 building in Sion through a district heating network. By capturing CO2 emitted from smoke stacks, the project will shrink EPFL’s carbon footprint, in line with its 2030 Climate and Sustainability Strategy. The capture process combines two technologies for which EPFL is at the cutting edge: graphene membranes that filter CO2, developed by Prof. Kumar Agrawal's research group, and sponges that can retain the filtered molecules, developed by Prof. Wendy Queen. The captured CO2 will be stored in liquid form for a range of end uses. SusEcoCCUS will also include research on improved technology for carbon capture directly from the air.

Conditions for large-scale deployment

The second aspect is carbon conversion and use. Jan Van Herle's research group, which specializes in electrolysis, has developed renewable-energy-powered electrolysers that can break down water molecules into oxygen and hydrogen. This clean hydrogen is then combined with CO2 to produce synthetic gases such as methane that can be transported, stored, and injected into existing natural gas grids. A small demonstrator will also be built to show how CO2 can be used to produce ethylene, a gas that forms the basis of a number of plastics.

The third aspect is carbon storage. Engineers at Prof. Lyesse Laloui's Soil Mechanics Laboratory are carrying out extensive research on CO2 sequestration. They will develop a unique, one-meter-long test bed for the geological storage of CO2, in order to assess short- and long-term storage capabilities.

Last but not least, SusEcoCCUS will explore how this kind of technology can be incorporated into production processes and life-cycle analyses. For example, Prof. François Maréchal’s research group, working in association with Marina Micari, will study the conditions for large-scale deployment of this technology as part of the energy transition, and Sascha Nick at EPFL’s Laboratory of Environmental and Urban Economics will examine the economic and financial aspects of CCUS. The project will also include an educational aspect, as students will be directly involved in the experimentation process.