Multi-Parametric Analysis of a District Cooling System Integrated with Energy Storage Technologies: A Case Study of a University Campus in Northern Europe

Abstract District cooling (DC) has emerged as a highly relevant pathway for reducing carbon emissions and enhancing energy efficiency. However, DC systems face operational challenges such as load variation and fluctuating electricity prices. Integrating energy storage technologies with DC systems offers a promising solution. Although several studies have been reported in literature, the potential of thermal energy storage (TES) for DC applications remains underexplored. This study aims to assess the feasibility of DC systems integrated with energy storage technologies, considering multiple parameters from technical, economic, and environmental domain. Data collection was conducted in the context of a university campus, depending on system alternatives and boundary conditions. Three system configurations (SC) were formulated to assess the impact of integrating energy storage: a typical DC plant (base case, BC), a typical DC system coupled with cold TES (SC1), and a DC system coupled with cold TES and electrical storage (SC2). At the system level, the observed energy efficiency ratios (EER) were 4.79 (BC), 4.78 (SC1), and 4.67 (SC2). This slight decline is attributed to the increased electricity consumption when energy storage is integrated. The economic assessment showed discounted payback periods of 7 years (BC), 5 years (SC1), and 6 years (SC2). While hybrid energy storage (thermal and electrical) reduced operational expenses, it increased investment and maintenance costs. Significant emission reductions were not achieved, as electricity remained the primary energy source in all configurations. The lowest and highest specific cooling emissions were found for BS (33.6 kgCO2/MWh) and SC2 (37.1 kgCO2/MWh), respectively. These findings are expected to strengthen the wider adoption of innovative DC solutions in the cities of Northern Europe.