Analysis of LNG cold energy utilization and regasification process for a gas turbine power plant integrated with a novel polygeneration process

Abstract

In the presented study, a polygeneration process is presented. This process consists of a gas turbine cycle, an internal trigeneration unit, an internal cogeneration unit, a proton exchange membrane electrolyzer, and a seawater desalination unit. This configuration is evaluated using thermodynamic, economic, and environmental analyses, and the outcomes are compared with similar examinations. The problem addressed is the enhancement of energy efficiency and reduction of carbon emissions in gas turbine power plants. This is crucial for improving sustainability and economic viability in power generation. Thermodynamic evaluation indicates that the energy efficiency, exergy efficiency, electrical efficiency, thermal efficiency, energy usage factor, and primary energy saving for the proposed process are 84 %, 76.09 %, 36.25 %, 39.91 %, 76.16 %, and 41.43 %, respectively. The system demonstrated a low CO2 emission intensity of 0.14 kgCO2/kWh. Key outputs include 2638.57 kg/s of hot water, 145.44 kg/s of chilled water, 1.12 kg/s of hydrogen, 8.89 kg/s of oxygen, 145.2 kg/s of fresh water, and 732300 kW of power. Economic analysis revealed a positive net present value with the total unit cost of the product at 6.104 USD/GJ and the cost of energy at 0.042 USD/kWh. The novelty of this work lies in its extensive heat recovery network, significantly enhancing thermodynamic efficiency and minimizing carbon emissions. The proposed system does not have any indirect CO2 emissions, making it environmentally superior to other methods. This integrated polygeneration process not only improves energy efficiency and environmental performance but also provides a sustainable and economically attractive solution for future power generation and resource production.