Switzerland has considerable capacity for carbon storage and a bright future in geothermal energy. These are the two main findings presented in Innosuisse's final report on the 2013-2020 Energy Funding Programme, in the chapter on geothermal energy. Lyesse Laloui, a full professor in civil engineering at EPFL, is the chapter's author and the head of a research group on this topic.
When the Swiss government decided to phase out nuclear power in the wake of the Fukushima accident on 11 March 2011, it also launched a major nationwide research program to explore alternative energy sources, with the goal of fully replacing the country's nuclear power with renewable energy by 2050. Some CHF 250 million in funding was deployed to develop and implement a comprehensive strategy. The nationwide research program entailed setting up eight Swiss Competence Centers for Energy Research (SCCERs) to explore seven energy-related topics. Universities and research institutes from across the country, in association with around 900 businesses and public-sector organizations, conducted 1,500 research projects through these Centers between 2013 and 2020. Innosuisse was commissioned to evaluate the results of the projects, and it issued its final report on 22 July 2021.
As part of this nationwide research program, EPFL led the effort in the area of geothermal energy, which included assessing Switzerland's potential for carbon storage and for deep and shallow geothermal energy. What are the main conclusions?
Carbon storage in Switzerland
"The research we've done over the past eight years shows that there's enough underground capacity in Switzerland to store large amounts of CO2, primarily in the Swiss Plateau, from Fribourg to Zurich," says Prof. Laloui. "In fact, the carbon storage process would be easier than burying nuclear waste." His team of experts estimates that 50-700 million tons of CO2 could be stored in Switzerland's soil. These would mainly be emissions from the construction industry (cement and steel production), the biochemicals industry and agriculture. "Of the 40 million tons CO2-eq emitted in Switzerland each year, some 12 million could potentially be stored underground. That means the country could become carbon-neutral, or even achieve negative emissions, for 70 years," says Prof. Laloui. However, he also points out that reaching this goal would require that today's greenhouse gas emitters decarbonize their production chains.
Over 20% share of shallow geothermal energy by 2035
Prof. Laloui's research on shallow geothermal energy indicates that there's considerable potential for this type of renewable resource. "The Swiss government had set a target of having 11% of the energy used for its buildings' heating and cooling systems come from geothermal energy by 2035. Our work shows that this percentage could easily be doubled," he says. With regard to deep geothermal energy - that is, natural heat located one to three kilometers underground - EPFL conducted a study with the Geneva Canton public utility which found that if heat accumulated during the summer was stored below Lake Geneva, it could be used to warm up some of the Canton's buildings during the winter.
The EPFL study also looked at the scope for using geothermal energy to generate electricity. For now, Prof. Laloui and his team see that as something that could be an option in the future. "Many researchers have looked at how rocks can be fractured without triggering seismic movements, but more research is still needed. We'll surely be able to do it one day, but we're not there yet."
Prof. Laloui believes a lot of important findings have come out of these years of intensive research. Switzerland now ranks among Europe's top centers of excellence in geothermal energy, and the joint effort by 250 scientists across the country has been highly effective. He now hopes that the research will be taken further. "I strongly encourage the Swiss government to set up a national research center on geothermal energy and carbon storage in order to leverage the discoveries we've already made and keep our solid skills in this area within the country."
