This paper presents the thermodynamic and hydrodynamic feasibility of the application of the ammonia water absorption system for heat or cold transportation over long distance. A model of a long-distance heat energy transportation system is built and analyzed, and it shows satisfactory and attractive results. When a steam heat source at the temperature of 120 degrees C is available, the user site can get hot water output at about 55 degrees C with the thermal COP of about 0.6 and the electric COP of about 100 in winter, and cold water output at about 8 degrees C with the thermal COP of about 0.5 and the electric COP of 50 in summer. A small-size prototype is built to verify the performance analysis. Basically the experimental data show good accordance with the analysis results. The ammonia-water absorption system is a potential prospective solution for the heat or cold transportation over long distance. Copyright (C) 2009 John Wiley & Sons, Ltd.