Hybrid systems based on gas turbine combined cycle for trigeneration of power, cooling, and freshwater: A comparative techno-economic assessment

Abstract

The objective of this study is to develop and thoroughly evaluate several feasible hybrid trigeneration configurations based on a gas turbine combined cycle (GTCC) for generating electricity, freshwater, and cooling. Six hybrid configurations are developed by integrating different desalination and chiller systems to the GTCC. Desalination systems include multi effect distillation (MED) and reverse osmosis (RO) with pressure exchanger (PEX) and chiller systems include double effect and half effect water-lithium bromide absorption chillers (DEABC and HEABC) and a vapor compression chiller (VCC) with different working fluids. The specific goal is to identify the optimal hybridization scheme and parameters among different configurations. The economic results show that implementation of RO is more economical than a hybrid MED-RO system in which the power cycle’s condenser is replaced by a MED. Also, the use of DEABC is more economical than a HEABC and a VCC. The results demonstrate that configuration 1 in which GTCC with the wet cooling tower is integrated with DEABC and RO is the most economical configuration. For this system, the levelized costs of electricity, water, and cooling (LCOE, LCOW, LCOC) are $0.0648/kWh, $0.7219/m3 and $0.0402/ton-hr, respectively, of which LCOE and LCOC are not the lowest values among different configurations.