Thermoeconomic and environmental analyses of a low water consumption combined steam power plant and refrigeration chillers-Part 2: Thermoeconomic and environmental analysis

Ifaei, P.,Ataei, A.,Yoo, C. Pergamon 2016 Energy Conversion and Management Vol. No.

The present paper is the continuation of Part 1 of a comprehensive study on new low water consumption combined steam power plants (SPP) and refrigeration chillers. Environmental, exergy, and thermoeconomic analyses of the steam power plant with natural draft wet cooling tower (SPP-NDWCT) as the base system, combined vapor compression refrigeration and the base system (VCR-SPP-NDWCT), and combined absorption heat pump and the base system (ABHP-SPP-NDWCT) are developed. The exergy analysis is conducted to analyze and compare the systems from an exergetic point of view and the thermoeconomic analysis is done to obtain the unit cost of the water loss in the systems' cooling towers. The environmental analysis is also carried out to obtain the annual environmental revenue of the saved water compared to the annual economic and environmental costs caused by consuming more fuel in the ABHP-SPP-NDWCT system. The results demonstrated that the NDWCT exergy loss, exergy destruction and total cost value decreased by 12%, 10.7% and 1.8% in ABHP-SPP-NDWCT system, respectively. Thus, the ABHP-SPP-NDWCT system could replace the conventional SPP-NDWCT system in regions where the environmental- economic value of water is higher than 1.081$/l.

Multi-scale smart management of integrated energy systems, Part 1: Energy, economic, environmental, exergy, risk (4ER) and water-exergy nexus analyses

Ifaei, Pouya,Safder, Usman,Yoo, ChangKyoo Pergamon 2019 Energy Conversion and Management Vol. No.

<P><B>Abstract</B></P> <P>A holistic analytical approach is proposed to study the performance of fossil fuel burning integrated energy conversion systems considering energetic, economic, exergetic, environmental and risk (4ER) aspects in a framework. For this, life cycle assessment is conducted to study environmental impacts while other analyses are performed using the algebraic thermo-mathematical programming. The hazardous risks are also investigated using a hazard and operability approach. The external hot and cold utilities are also studied using a novel water-exergy nexus (WExN) analysis. Accordingly, two configurations are developed that integrate a Rankine cycle (RC) and an ejector refrigeration cycle (ERC) for two purposes: power and cooling co-generation (CGS) and power generation (MGS). Water losses in both systems are studied considering three cold utilities and two fossil fuel cycles using the WExN analysis, and the performance of the CGS and the MGS are compared employing several organic fluids. The results showed that the MGS had greater energetic and exergetic efficiencies, better environmental performance, and less hazardous risk impacts compared to the CGS employing almost all working fluids. The smallest exergy loss in the cooling system was 3.90 MW and 7.94 MW in the MGS allocating R123 and the CGS using R718, respectively.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A comprehensive analysis for evaluating energy conversion systems is described. </LI> <LI> A novel water-exergy nexus analysis is employed to evaluate hot and cold utilities. </LI> <LI> A mathematical program is developed to model two integrated energy systems. </LI> <LI> According to 4ER, power generation was preferred to power/cooling cogeneration. </LI> <LI> Allocating steam caused less risks and costs but great water losses in cold utility. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A systematic approach of bottom-up assessment methodology for an optimal design of hybrid solar/wind energy resources – Case study at middle east region

Ifaei, Pouya,Karbassi, Abdolreza,Jacome, Gabriel,Yoo, ChangKyoo Elsevier 2017 Energy conversion and management Vol.145 No.-

<P><B>Abstract</B></P> <P>In the current study, an algorithm-based data processing, sizing, optimization, sensitivity analysis and clustering approach (DaSOSaCa) is proposed as an efficient simultaneous solar/wind assessment methodology. Accordingly, data processing is performed to obtain reliable high quality meteorological data among various datasets, which are used for hybrid photovoltaic/wind turbine/storage/converter system optimal design for consequent sites in a large region. The optimal hybrid systems are consequently simulated to meet hourly power demand in various sites. The solar/wind fraction and net present cost of the systems are then used as the technical and economic clustering variables, respectively. The clustering results are finally used as input to obtain novel hybrid solar/wind GIS maps. Iran is selected as the case study to validate the proposed methodology and detail its applicability. Ten minute annual global horizontal radiation, wind speed, and temperature data are analyzed, and the optimal, robust hybrid systems are simulated for various sites in order to classify the country. The generated GIS maps show that Iran can be efficiently clustered into four technical and five economic clusters under optimal conditions. The clustering results prove that Iran is mainly a solar country with approximately 74% solar power fraction under optimum conditions. A macroeconomic evaluation using DaSOSaCa also reveals that the nominal discount rate is recommended to be greater than 20% considering the current economic situation for the renewable energy sector in Iran. An environmental analysis results show that an average 106.68tonCO<SUB>2</SUB>-eq/year is produced for such hybrid systems application in Iran during a cradle to grave life cycle. Thus, Iran energy sector can be eminently promoted to an environmentally efficient stage with regard to the proposed classification plan and economic considerations.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Proposing DaSOSaCa flowchart as a novel hybrid solar/wind assessment approach. </LI> <LI> Calculating four key parameters to generate synthetic wind hourly data for Iran. </LI> <LI> Proposing technical and economic hybrid solar/wind GIS maps of Iran. </LI> <LI> Revising renewable energies management plans of Iran by macroeconomic evaluation. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Thermoeconomic and environmental analyses of a low water consumption combined steam power plant and refrigeration chillers - Part 1: Energy and economic modelling and analysis

Ifaei, P.,Rashidi, J.,Yoo, C. Pergamon ; Elsevier Science Ltd 2016 Energy conversion and management Vol.123 No.-

Two novel configurations are proposed to replace the conventional Rankine cycle based steam power plants (SPP) with natural draft wet cooling towers (NDWCT) as cooling units. Closed feedwater heater unit of the base SPP-NDWCT system is eliminated in order to combine a vapor compression refrigeration (VCR) and an absorption heat pump (ABHP) with the base SPP-NDWCT system. Both VCR-SPP-NDWCT and ABHP-SPP-NDWCT systems are integrated to decrease the NDWCT load which could result in water losses decrease. In part one of the presented two-part paper, model-based energy and economic analyses are performed to compare systems performance and applicability. The temperature difference at pinch point and temperature difference between the hot and cold sides of the heat exchangers which were used for systems integration in VCR-SPP-NDWCT, and the absorber pressure and temperature in ABHP-SPP-NDWCT system are studied using parametric analysis procedure. A water-fuel management strategy is also introduced for the ABHP-SPP-NDWCT system according to the influence of the absorber pressure changes on system water and fuel consumption. In part 2, environmental and thermoeconomic analyses are performed to complete a comprehensive study on designing steam power plants. The results of part 1 showed that water losses and total annual costs decreased by 1-18% and 0-4.7% for the ABHP-SPP-NDWCT system but increased by 11% and 60% for the VCR-SPP-NDWCT system, respectively.

A renewable energies-assisted sustainable development plan for Iran using techno-econo-socio-environmental multivariate analysis and big data

Ifaei, Pouya,Karbassi, Abdolreza,Lee, Seungchul,Yoo, ChangKyoo Elsevier 2017 Energy conversion and management Vol.153 No.-

<P><B>Abstract</B></P> <P>In the present study, sustainable development is investigated in Iran using renewable energies-assisted Techno-Econo-Socio-Environmental Multivariate Analysis (TESEMA) as a novel holistic approach. Accordingly, six annual hourly consumption variables, reported by Iran’s power industry from 2011 to 2017, are predicted using seven dynamic and intelligent models. Consequently, technical and economic variables are obtained by an optimal design of hybrid solar, wind, and biogas systems at 53 sites in Iran. Thirteen social variables are studied using a technique for order-preference by similarity to an ideal solution (TOPSIS) and six hazardous air pollutants are reported in Iran using a geographic information systems interpolation tool. Then, four major TESEMA variables are used in multivariate statistical analyses to reduce the big data diversity. Principal component analysis (<I>PCA</I>) is performed to find a linear model among the variables, and <I>K</I> nearest neighborhood (<I>KNN</I>) algorithm is used to cluster the sites according to the modeling results. A partial least square-based regression is conducted to investigate any correlation between major variables of TESEMA and population density in Iran. Finally, TESEMA development index (<I>DI</I>) and facial graphs are proposed as novel numerical and graphical sustainable development monitoring techniques, respectively. The results show that <I>DNN</I> is the best model to predict demand load in Iran (<I>RMSE</I> = 73.15%). Since <I>DI</I> varies in a wide range from 0 to 248.83 and the population density is significantly correlated with TESEMA variables (<I>R</I> <SUP>2</SUP> = 91.86%), the current centralistic policies should be revised in Iran to reach sustainable development. Thus, a four-cluster management strategy accompanied by smart monitoring can efficiently lead to sustainable development in Iran.</P> <P><B>Highlights</B></P> <P> <UL> <LI> TESEMA is proposed as a novel green energy-assisted sustainable development plan. </LI> <LI> A hybrid solar/wind/biogas optimal design algorithm is proposed. </LI> <LI> Techno-economic-socio-environmental big-data matrices are constructed for Iran. </LI> <LI> Facial graphs are proposed as a novel graphical approach for development monitoring. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

An optimal renewable energy management strategy with and without hydropower using a factor weighted multi-criteria decision making analysis and nation-wide big data - Case study in Iran

Ifaei, Pouya,Farid, Alireza,Yoo, ChangKyoo Elsevier 2018 ENERGY Vol.158 No.-

<P><B>Abstract</B></P> <P>In the present study, an optimal renewable energy management strategy (REMS) is proposed as a sustainable policy for non-fossil fuel-based centralistic energy policies. Accordingly, the demand load data and weather big datasets were analyzed using neural networks and analysis of variance, respectively. Biogas generation was modeled using a BSM2 dynamic model, and the available hydropower was evaluated in the form of a techno-economic assessment. A hybrid solar PV/wind turbine/biogas generator/hydroturbine/battery/inverter system was simulated as a gauge unit using the processed data to evaluate the potential of all renewable energies in Iran. The results were used to cluster Iran into various classes based on optimal green energy potential using a <I>K</I>-means algorithm. A factor analysis (FA) was performed using a big matrix consisting of 13 social, economic, environmental, and technical variables in all of Iran's provinces. Factor score coefficients were then employed in a mature multi-criteria decision making analysis technique to determine the order preference for an ideal solution (TOPSIS). These details were used to inform the REMS. The optimal hybrid renewable energy maps were generated and were combined with the FA-TOPSIS results to produce an action plan proposal. The results show that FA can explain 99% of the variance in the big data matrix. Iran can be efficiently clustered into five classes, while a four-stage action plan can assure sustainable development.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Optimal solar/wind/biogas/hydropower and solar/wind/biogas maps are drawn for Iran. </LI> <LI> A renewable energy management strategy is detailed using the FA-TOPSIS approach. </LI> <LI> A big decision making matrix is constructed including 13 key variables in Iran. </LI> <LI> A flexible action plan is proposed for a practical sustainable development in Iran. </LI> </UL> </P>

지속가능 에너지생산 및 기후변화적응을 위한 다양한 신재생에너지 자원들의 최적 평가 기법 개발

Pouya Ifaei,Usman Safder,ChangKyoo Yoo 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.12

Prediction of Korean electricity consumption using sequential neural networks

Pouya Ifaei,Amir Saman Tayerani Charmchi,Changkyoo Yoo 대한환경공학회 2020 대한환경공학회 학술발표논문집 Vol.2020 No.11

Availability and reliability analysis of integrated reverse osmosis - forward osmosis desalination network

Safder, Usman,Ifaei, Pouya,Nam, KiJeon,Rashidi, Jouan,Yoo, ChangKyoo Desalination Publications 2018 Desalination and Water Treatment Vol.109 No.-

Multi-objective optimization and flexibility analysis of a cogeneration system using thermorisk and thermoeconomic analyses

Safder, Usman,Ifaei, Pouya,Yoo, ChangKyoo Elsevier 2018 Energy conversion and management Vol.166 No.-

<P><B>Abstract</B></P> <P>In the present study, an optimal power and freshwater cogeneration system is proposed to meet the global requirements sustainably. A Rankine cycle (RC), an organic Rankine cycle (ORC) and a reverse osmosis (RO) module are integrated to form the proposed system. The performance of the system is investigated using thermo-mathematical models allocating seven organic fluids in the bottoming ORC. A novel evolutionary algorithm-based multi-objective optimization approach is applied using thermorisk and thermoeconomic analyses. Thus, an optimal configuration is determined at both global and local scales. Finally, a flexibility analysis is performed to the optimal configuration considering probable uncertainties in the market. The optimization results showed that the total accidental risk impact and the total product cost rate improved by 2.49–48.73% and 5.67–62.41%, respectively, depending on the employed organic fluid. The highest exergetic efficiency and the minimum specific power consumption were obtained as 52.74% and 4.111 kWh/m<SUP>3</SUP>, allocating R245fa in the optimal system. The system enjoying R123 had the widest flexibility range without any increases in the optimum total product costs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A cogeneration system is optimized decreasing thermoeconomic and thermorisk impact. </LI> <LI> The system’s flexibility is analyzed investigating the uncertainties of the market. </LI> <LI> Various cases are studied with respect to the properties of working organic fluids. </LI> <LI> The cost product rate and specific risk improved by 62.41% and 48.73%, respectively. </LI> <LI> The highest exergetic efficiency was obtained to be 52.74% using R245fa. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>