Utilizing Underground Spaces for Sustainable Energy Infrastructure: A Feasibility Study in Zurich's Inner-City

This feasibility study explores the utilization of underground spaces for energy infrastructure in Zurich's inner city, focusing on the expansion of the district heating network. The proposed shift from the Selnau substation to alternative underground sites aims to integrate multifunctional, resilient infrastructure. Key solutions include a centralized cavern concept in the University district of Zurich and reusing existing underground structures like the decommissioned Letten Tunnel for seasonal heat storage. The study evaluates multiple underground options, prioritizing sustainability, urban resilience, and efficient resource use. The findings recommend further investigation into cavern-based heating systems, offering Zurich a pathway to an innovative, future-proof energy network, without taking away publicly used surface spaces.