Interaction between energy transfers in an absorption machine

Abstract

In 1981 a Research Centre was set up at Marsaxlokk by joint Austrian and Maltese interests. The principal aim was to study in all its aspects the feasibility of using solar energy in domestic and industrial use leading to the production of the required plant here in Malta. One of the projects initiated was to use solar energy to power an ammonia/water refrigeration absorption machine of Austrian design. This would then be used in a cooling unit for food storage and preservation. The plant was accordingly set up but for some reason seems never to have been tested as no records of tests exist. For this reason, the new director of the Centre put forward an idea for a thesis involving the testing of this equipment. Originally, when accepting this project, the intention was to carry out tests to compare the performance of the system using two forms of heat source, namely waste heat from the exhaust of a diesel engine and hot water obtained from a bank of parabolic solar concentrators. This would then lead to the derivation of the machine coefficient of performance (COP) thereby enabling the economics of the plant to be evaluated vis-a-vis other, more conventional, refrigeration systems. Unfortunately, these intentions have had to be considerably modified due to a fact which at first was not appreciated fully, namely the very poor state of the machine. As will be explained later the work needed to bring the machine into working order took far longer than originally anticipated. When in August, after much improvisation, one bank of concentrators was brought to working order and the machine filled with ammonia/water solution it immediately developed a new fault before any tests could be made.