Comparative analysis of scenarios of data center waste heat utilization for district heating networks of different generations

The growth of global telecommunication infrastructure offers significant opportunities for harnessing data center waste heat. This study focuses on analyzing and comparing several scenarios — business as usual (BAU), data center waste heat recovery (WH), and WH complemented by a shallow borehole thermal energy storage addressing the mismatch between heat demand and waste heat production (WH + BTES) — under various district heating (DH) temperatures representing different generations of DH networks. The north campus in Göttingen serves as a case study. We used a customized Python model, incorporating the pygfunction package and a regression-based heat pump model, to assess the thermal response factors (g-functions) of geothermal borehole fields and to perform the analysis. The results demonstrate that around 70 % of the considered heating and cooling demand can be covered in the WH scenario and additionally about 20 % in the WH+BTES scenario. Currently, the WH scenario is economically most promising, while the WH+BTES scenario allows for higher CO₂ savings. The sensitivity analysis further indicates that storing waste heat could become economical if the BTES capital cost were reduced by 35 % and the ratio of DH price to electricity price increased to 2.5 times the current value. For the WH scenario, the range of marginal waste heat prices was determined using Monte Carlo simulations. The average values obtained are 48, 56, 90, 93 €/MWh_wh for the DH design supply temperatures of 120, 95, 70, 48 °C, respectively. Thus, low-temperature district heating operators can expect larger profits if waste heat prices are constant for all network temperatures.