4E Analysis of Power and Water Cogeneration Plant based on Integrated MED-TVC and RO Desalination Units

In this study, optimization of Qeshm power and water desalting cogeneration plant has been investigated. The objective functions are related to maximizing exergetic efficiency and minimization of exergoeconomic and exergoenvironmental parameters. Also, the integration of RO desalination with the existing plant has been evaluated based on these analyses. This plant includes two MAPNA 25 MW gas turbines, two heat recovery steam generators, and two MEDTVC desalination units. Thermodynamic modeling and simulation of the plant have been performed in MATLAB software. The thermodynamic simulation verified by Thermoflex software and plant data with high accuracy. Also, the computer code has been developed to perform exergetic, exergoeconomic and exergoenvironmental analysis. Multi-Objective Genetic Algorithm (MOGA) has been applied to find optimum objective functions and decision variables based on exergetic, exergoeconomic and exergoenvironmental parameters. Results show that in the optimum plant overall exergetic efficiency of the plant has been increased by 27.78%, and total exergetic cost and total exergoenvironmental impacts have been decreased by 0.93% and by 0.89%.

In this paper, full repowering of a 320 MW steam power plant was investigated in Bandar Abbas. Due to unavailability of natural gas in the winter, LNG, Diesel, and Heavy fuel were examined as alternative fuels. The energetic, exergetic, exergoeconomic, and exergoenvironmental (4E) analyses were performed for old and repowered cases. The exergoenvironmental analyses were done based on the Life Cycle Assessment in SimaPro software. The net power, fuel consumption, costs, and environmental impacts were calculated by considering different fuels for each season. To better demonstrate the plant performance, the exergy destruction level (EDL) and the exergy cost destruction level (ECDL) were defined and applied as EDL/ECDL. To perform this analysis, a computer program was developed that could predict the base cycle and repowered cycle behaviors for different operating conditions with relative errors of less than 1.85%. Results demonstrated a 16% increase in the overall cycle efficiency, a 12% decrease in the methane consumption, and a 3% elevation in the net power using the LNG fuel.

Energy, exergy, exergoeconomic and exergoenvironmental analyses of a hybrid renewable energy system with hydrogen fuel cells

In this paper, freshwater production through multi-effect desalination (MED), multistage flash (MSF), reverse osmosis (RO), hybrid (MED-RO), and hybrid (MSF-RO) units have been investigated based on environmental impacts associated with life cycle assessment (LCA) modelling tool and exergoenvironmental analysis. The integration of Qom combined cycle as a real case study with selected desalination plants has been studied. In this regard, thermodynamic simulation has been performed in computer code with high accuracy. Furthermore, computer code has been developed to perform exergy, exergoeconomic, and exergoenvironmental analyses. Results show; the environmental impact rate associated with the integrated combined cycle with the MED unit decreased by 23% compared to the stand-alone power plant. Also, in the integration of combined cycle with MSF, RO, MED-RO, and MSF-RO, it has been found that 25%, 60%, 27%, and 25% decrease can be obtained in the environmental impact rates, respectively.

4E dynamic analysis of a water-power cogeneration plant integrated with solar parabolic trough collector and absorption chiller

Herein, a comparative energetic and life‐cycle assessment (LCA) study is performed on coal and natural gas‐based combined heat and power cogeneration plants. Different types of power plants, including gas turbine, steam turbine, and combined‐cycle plants, are considered. Three types of LCA methodologies, including CML 2001, TRACI, and ReCiPe, are used to analyze the life‐cycle environmental impacts of each plant. The coal‐based cogeneration plant is found to entail the comparatively lowest life‐cycle energy efficiency of 43.6%, and the natural gas‐based combined‐cycle cogeneration plant is found to have the highest efficiency of 59.6%. Furthermore, the coal‐based life cycle is also found to entail the highest life‐cycle environmental impacts comparatively. According to CML 2001, it entails a global‐warming potential of 0.229 kg CO2eq MJ−1 and an acidification potential of 7.03E‐4 kg SO2eq MJ−1. The natural gas‐fired boiler‐type cogeneration plant is observed to have a comparatively higher toxicity and eutrophication potential of 2.72E‐4 kg DCBeq MJ−1 and 2.78E‐5 kg PO4eq MJ−1, respectively. The lowest overall life‐cycle environmental impacts comparatively are found to be associated with the natural gas‐based combined‐cycle cogeneration plant.

In this article, a new procedure was introduced for the optimal design of utility system in process industries. This method was based on the development of the R-curve concept and a new cogeneration targeting through estimating costs, environmental impacts, exergoeconomic, and exergoenvironmental analyses. In the exergoenvironmental analysis, the environmental impacts obtained by life cycle assessment are apportioned to the exergy streams pointing out the main system components with the highest environmental impact and possible improvements associated with these components. Moreover, exergoenvironmental variables are calculated, and an exergoenvironmental evaluation is carried out. In this regard, correlations for estimating the environmental impacts of cogeneration system have been introduced. In addition, the powerful and accurate cogeneration targeting method was applied. Also, the new graphic representations have been proposed. These curves are based on cost estimation, environmental impacts, and exergoenvironmental analysis. In addition, the optimal design of site utility was carried out in Iran LNG cogeneration plant, in which the usefulness of this method was clearly demonstrated.

Energy, exergy, exergoeconomic, and exergoenvironmental analysis of an innovative solar-geothermal-gas driven polygeneration system for combined power, hydrogen, hot water, and freshwater production

Exergoenvironmental analysis of bioenergy systems: A comprehensive review

Comparative analysis of different cost allocation methodologies in LCA for cogeneration systems

Energy, exergy, exergoeconomic, and exergoenvironmental (4E) analysis of a new bio-waste driven multigeneration system for power, heating, hydrogen, and freshwater production: Modeling and a case study in Izmir

Amidst the current global pursuit for access to energy by all as well as energy transition, the actual performance of existing power plants, particularly in developing countries, has often attracted little interest in scientific research. This study evaluated the performance of selected power plants in Uganda using the techno-economic performance assessment model based on actual operational data of hydropower, solar photovoltaic, cogeneration, and thermal power plants for the period 2010–2021. The analysis revealed that the average combined capacity factors are 19.8%, 22.9%, 18.4% and 58.6%, respectively, for thermal power plants, co-generation power plants, solar power plants and hydropower power plants. Furthermore, the levelised cost of electricity for the selected power plants’ financial performance is found to be lower than the retail price for a unit of electricity in Uganda. Overall, the study revealed that the real-life techno-economic performance of the selected power plants in Uganda agrees with the globally expected performance ranges.

Consolidating exergoeconomic and exergoenvironmental analyses using the emergy concept for better understanding energy conversion systems

Exergoenvironmental analysis concerning the wood chips and wood pellets production chains

Conventional and advanced exergy-exergoeconomic-exergoenvironmental analyses of an organic Rankine cycle integrated with solar and biomass energy sources