The Empa campus features a district heating and cooling system. Three networks operating at high, medium, and low temperatures are present.
A BTES system comprising 144 boreholes 100m deep, is currently under construction. The BTES plumbing can be dynamically changed, either in a configuration with eight in-series circuits including 18 GHXs each, or a configuration of all the GHXs connected in parallel (Figure 2). The ground heat exchangers (GHXs) are of double-U type, with the outer ones made of PE-100 RC and the inner ones made of PE-100RT to withstand higher temperature loads. Each one of the in-series circuits is instrumented with energy meters, measuring the HTF flow and inlet and outlet temperature from the field. Thirteen BTES boreholes will also be equipped with fiber-optic cables to measure the ground temperature with a 2 m spatial resolution. The ground temperature measurement will be undertaken in three radial directions.