Biogas fueled combined cooling, desalinated water and power generation systems

This paper designs a novel biogas fueled combined cooling, fresh water and power (CCWP) generation system, and investigates its performance under extremely-hot summer days. In this tri-generation system, biogas is used as clean resource to reduce emissions and consumption of fossil fuels. Six electrical chillers are used for cooling demand supply of a benchmark building located in Ahwaz, Iran. In addition, expected required power of chillers and building is supplied either by gas turbine cycle or by main grid (If total power consumed by chillers and electrical equipment is larger than output power of gas turbine, building owner pays for purchasing electricity from local power system to satisfy not-supplied demand). A low-grade waste heat is extracted from the flue gases for preheating purpose and closed-air open-water humidification dehumidification (HDH) desalination process. In addition, a mixed integer non-linear programming problem is solved to minimize an objective function composed of daily electricity cost, total capital investment, operation and maintenance cost of CCWP generation system considering all operational limitations of gas turbine cycle, chillers, HDH process, and strategic cooling and electrical demand response programs (DRPs). If ambient air decreases, gas turbine power and mas flow rate of potable water will be increased due to lower compressor power and higher absolute humidity of air, respectively. Application of DRPs reduces total electricity cost from 31.2$ to 16.4$. Utilization of biogas and waste heat recovery of flue gases with no need to combustion of fossil fuels results in emission reduction. Hence, this tri-generation plant is called a net-zero emission system. (C) 2019 Elsevier Ltd. All rights reserved.