Competitiveness of district cooling in energy efficient supermarkets

Abstract: This thesis concerns utilization of district cooling in supermarkets. Today, district cooling isprimarily used in hotels, hospitals, offices and computer centrals. This study investigates thepossibility to expand the range of customers to also include supermarkets. The studied useincludes comfort cooling as well as condenser cooling. Condenser cooling implies increasingthe COP of a chiller by decreasing its condensation temperature. Chillers are inevitable sincethe temperature levels of chilled and frozen food are too low to directly use the districtcooling.The aim of the thesis is to determine the highest possible price of district cooling thesupermarket owner is willing to pay in order to connect the supermarket to the district coolingnetwork.Two different reference supermarkets are analysed, one representative for a supermarkettoday and one representative for a future supermarket. The major difference is the energyefficiency of the display cabinets.Four different system designs are investigated, using district cooling for both comfort coolingand condenser cooling, not using district cooling at all, using district cooling only for comfortcooling and finally, using district cooling only during the warm part of the year.The results show that the prices charged for district cooling are in general too high to makedistrict cooling competitive in a typical supermarket today. In the typical supermarket in thefuture it is more favourable. Using district cooling in the future reference supermarket forboth comfort cooling and condenser cooling implies an annual demand of 331 MWh and acompetitive price of 216 SEK/MWh. Using district cooling only when the outdoortemperature exceeds 10 °C implies a demand of 210 MWh/year and a competitive price of290 SEK/MWh and using district cooling only for comfort cooling implies a demand of 80MWh/year and a competitive price of 599 SEK/MWh.The typical future supermarket is fully possible to design at the present day, this woulddecrease the energy demand substantially and make district cooling competitive.