Geothermal energy: It's time we try something new

With years of experience in the industry, Brice Lecampion joined ENAC as a tenure track professor in June. With him comes a unique set of skills and experience in the engineering of deep wells, notably hydraulic fracturing and well cementing. Heading ENAC’s Geoenergy Laboratory (GEL), Lecampion will use numerical simulations and laboratory experiments to study the propagation of fluid-driven fractures in underground environments, pushing the envelope in terms of the fidelity with which they replicate structural properties of rock formations.

“After ten years in the industry, I’m excited to be coming back to academic research, where you are given more time to devote yourself to longer term projects,” says Lecampion. Trained as a geophysicist and mechanical engineer at the Universite Paris VI and the Ecole Polytechnique in France, Lecampion went on to spend a decade as a researcher and project manager in the industry, where he was involved in managing projects related to the development of new technologies for CO2 storage as well as unconventional oil and gas reservoirs.

“At ENAC, my work will focus on the injection and extraction of fluids for geo-energy applications, such as geothermal energy harvesting, carbon dioxide geological storage, or conventional fossil fuel production,” he says. With a grant from the Swiss National Science Foundation, he will initially seek to better understand the propagation of fractures in anisotropic rocks. “Even today, fracking is studied as a process that takes place in an isotropic medium. That assumes that directionality doesn’t matter. In other words, whichever direction they go, the cracks will always spread in the same way. In reality, however, directionality does matter. The problem today is that there is still little knowledge on how things change in an anisotropic medium.”

Better models of how cracks spread underground under fluid injection will help ensure the safety of hydraulic fracturing and increase the efficiency of the approach. At the same time, it will be able to guide the development of new technologies, for example in the field of geothermal energy extraction. “For thirty years, we have been applying the same approach to deep geothermal energy harvesting, with little to show for it: worldwide only a handful of projects so far are economically viable.” And sometimes, he says, they lead to earthquakes, triggered by the water that is constantly injected into the wells at a high pressure.

“It’s time we try something new. What if instead we developed an approach that works at lower injection pressure by first creating an engineered fluid pathway by hydraulic fracturing the rock between two parallel horizontal wells?” he asks. The high temperatures four to five kilometers below the surface and the crystalline structure of the rock are two obstacles for the current technologies that would have to be overcome before being able to apply this approach in or around Switzerland. But if it works, it would contribute to achieving Switzerland’s target of meeting 7% of its electricity needs using geothermal energy by 2050.

Lecampion’s arrival in the faculty coincides with that of Marie Violay, an expert in experimental research towards the development of deep geothermal energy harvesting, who recently joined ENAC as a tenure track professor in experimental rock mechanics. Together with Lyesse Laloui and Jean-François Molinari, they will form a new pole of expertise in geo-engineering and geomechanics.