Yonathan Hutagalung
From High-Temperature to Low-Temperature Geothermal
Yonathan “Hary” Hutagalung came to ISE from Indonesia with a background in geology and experience studying geothermal systems. After completing a BSc in Geology at the University of Canterbury in New Zealand, Hary had primarily focused on high-temperature geothermal resources. His studies at the Iceland School of Energy gave him the opportunity to broaden that perspective and explore how lower-temperature resources can also contribute to sustainable energy systems.
Exploring thermogeology in Slovenia
During his MSc studies, Hary participated in the International Summer School on Thermogeology in Ljubljana, Slovenia. The programme combined lectures, fieldwork and site visits focused on shallow and low-temperature geothermal energy. It introduced Hary to technologies for geothermal heating, resource utilisation and the operation of systems that differ considerably from the high-temperature geothermal environments he had previously studied.
One of the experiences included visiting a project where an existing gas well had been repurposed for geothermal energy production.For Hary, studying low-temperature resources offered a different perspective on geothermal development. Coming from Indonesia and having studied in New Zealand, both places strongly associated with high-temperature geothermal systems, the experience demonstrated how geothermal energy can also be used in regions without volcanic, high-temperature resources.
Building a broader geothermal perspective
The international experience complemented Hary’s studies at ISE and helped broaden his understanding of how geology, technology and local resource conditions shape geothermal development. His MSc thesis continued that subsurface focus by investigating the modelling of permeable aquifers associated with contact zones between basaltic lava flows. Together, his studies in Iceland, field experience in Slovenia and previous geological training illustrate how an existing specialisation can expand during graduate study into a broader understanding of geothermal energy systems.