Recently, Manzela and co-authors [20,21] evaluated the performance of a domestic absorption refrigerator modified for hot gas intake provided by a commercial 1.6 l four cylinder automotive engine. The impact of adapting the absorption chiller on engine performance, chemical composition of the exhaust gases, and fuel consumption was evaluated. The authors showed that, in spite of the low coefficient of performance (approximately 0.05), it was possible to reduce the average temperature in the refrigerator to close to 5 C. Diverting exhaust gases to power an absorption refrigeration system does not cause a significant pressure drop in the exhaust flow, nor does it lead to an increase in the level of
carbon emissions [20]. The authors also demonstrated that performance of the absorption refrigeration system powered by exhaust gas energy is hampered by excessive heat transfer to the absorption system, which occurs for higher engine speeds [8,20,21]. In this situation, exhaust gas temperature is increased considerably so that the refrigerant leaving the generator in the absorption cycle overheats and condensation is not achieved in the condenser. As a consequence, the evaporator temperature is raised and refrigeration does not occur. This highlights the importance of properly managing the amount of recovered heat in cogeneration systems based on ICEs [22].