District Cooling Using Absorption Chiller for a Network

One of the challenges for implementing this approach is to have the certain temperature requirements that have to befulfilled. The district cooling supplies chilled water at 6 °C and returning water at 12 -16 °C. The district heatingcompany desires to have the returning hot water temperature to be as low as possible, as it give benefits in term of lesspump work, and energy recovery for the condensation process at central heating plant. Furthermore, the requirement of6/12 °C is important to maximize the amount of cold distributed per unit volume of water pump. Having analyzed thepotential of absorption cooling driven by district heating, the main objective of this paper is to examine the temperaturedifference (cool-off) of the hot water circuit at input of 70 °C in the decentralized absorption cooling system driven bydistrict heating network with outgoing and returning chilled water respectively at 6 °C and 12 °C. The results of thesimulation show that the COP value decreases as the cool-off increases. The analysis is done with zero-order model that is able to predict theminimum heat input temperature needed to drive the absorption system at nominal COP. It shows that the larger the cool-off, the higher theheat input temperature needed to avoid the decreasing of COP.

Keywords:

district cooling , Absorption chiller , NH3-H2O , Thermal Driven Cooling (TDC)