District heating assisted ejector cycle refrigeration plant for process cooling and air-condition purposes

In this paper, a demonstration plant situated in Denmark using a district heating assisted high performance ejector as compression device and water as refrigerant will be discussed. Starting with some basic ejector theory leading to the practical aspects of ejector refrigeration, an actual demonstration plant being built at this moment will be presented. Finally, an economical and environmental comparison of a traditional absorption plant and an ejector plant both using surplus production district heating as energy source will be discussed. Based on data from the ejector manufacturer and a Danish standard air-condition load profile, calculations show an expected weighted yearly average COP of 1.38 on the demonstration plant. Using this COP as reference for ejector plants, the lifetime cost level comparisons made on eight plants at capacities between 75 and 7800 kW show that at capacities above 400 kW, a well-designed ejector cycle cooling plant is the economically and environmentally best solution of all three.