Energy, exergy, and environmental analysis of meeting cooling demand of a ship with waste heat recovery

Waste heat recovery for meeting the air conditioning demand of a ship is reported. An absorption refrigeration system is proposed. Water-LiBr is used as the working pairs for this purpose. A steady-state energy, exergy, and environmental analysis is done to compare the proposed system with the conventional system. Exhaust gases of auxiliary engines are used to vaporize high-pressure water. High-pressure steam is employed as a heat source for the generator of the absorption system. The results show that exhaust gases of the auxiliary engine as a permanent heat source suffice for the generator of the absorption system. For tropical conditions, the required power for the absorption system is much lower than that for the conventional system. (Ẇdemand\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\dot{\Big(W}}_{\mathrm{demand}} $$\end{document} for the absorption system is 0.02, while it is 88.28 for the conventional system). The second law of thermodynamics shows a 31% lower total irreversibility in the proposed system versus the conventional system. The use of the absorption system causes a USD 45,078 saving in the yearly penalty cost of CO2 emission.