The role of geothermal plants in the global energy and materials transition

Although geothermal technology and global capacity for power and heat are advancing, its role in the transition to sustainable energy systems remains notably underexplored. This review finds that many existing energy system models rely on simplified techniques that fail to adequately address the complexities of exploration uncertainties and nonlinear drilling costs. Current linear approaches tend to over- and underestimate drilling costs at lower (+420% at 1 km) and higher depths (−50% at 10 km), respectively. In addition, important factors such as life cycle environmental and social impacts are often overlooked. We synthesize key data sources and identify best modeling practices for geothermal plants, examining fixed versus variable drilling depths, as well as detailed cost functions. Crucially, we position geothermal energy within the broader energy-material nexus, emphasizing how geothermal systems can contribute not only to decarbonization but also to reducing pressure on critical raw material supply chains. Further innovations such as the flexibility of geothermal plants in load-following operation, and the potential for technological learning through policy support are identified as key game changers that could enhance the role of geothermal energy in future systems.