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Nishith B Desai - One of the best experts on this subject based on the ideXlab platform.

  • optimization of waste heat based Organic Rankine Cycle powered cascaded vapor compression absorption refrigeration system
    Energy Conversion and Management, 2017
    Co-Authors: Bhavesh Patel, Nishith B Desai, Surendra Singh Kachhwaha
    Abstract:

    Abstract In this paper, the thermo-economic optimization of the waste heat based Organic Rankine Cycle powered cascaded vapor compression-absorption refrigeration system is presented. Organic Rankine Cycle with dry Organic working fluid is used as a power generating Cycle to provide input to the vapor compression refrigeration system. Moreover, the high temperature Organic working fluid at the expander outlet is used to supply thermal need of the vapor absorption refrigeration system. The present system achieves low temperature cooling efficiently. However, initial capital cost and complexity are the practical limitations for the present system. The energetic efficiency of the present system for only cooling mode and cogeneration mode (cooling and heating) are calculated to be 22.3% and 79%, respectively. It may be noted that the extra heat available, apart from the thermal energy requirement of the vapor absorption system, is taken as process heat in the cogeneration mode. The simple payback period and break-even point are calculated (for the base case) to be 5.26 years and 4.22 years, respectively. The system size and annualized cost are optimized, using nonlinear programming based on conjugated directions method, to make the system potentially attractive for the industrial sector. Optimization results reveal that the annualized cost of the present system is decreased by about 12% compared to the base case. Moreover, the simple payback period and break-even point are reduced to 4.50 years and 3.48 years, respectively. The results of comparative economic study, between the present and stand-alone vapor compression refrigeration systems, show that the higher value of electricity price and the lower value of discount rate are favorable for the selection of the present system.

  • thermo economic analysis of a novel Organic Rankine Cycle integrated cascaded vapor compression absorption system
    Journal of Cleaner Production, 2017
    Co-Authors: Bhavesh Patel, Nishith B Desai, Surendra Singh Kachhwaha, Vaibhav Jain, Nanji J Hadia
    Abstract:

    Abstract Integration of thermal systems improves the energy efficiency and reduces the carbon emissions. In this paper, a novel trigeneration system, which integrates the Organic Rankine Cycle and vapor compression–absorption cascade refrigeration Cycle is proposed. The cascade refrigeration system combines the advantages of the conventional stand-alone vapor compression system and vapor absorption refrigeration system. The energetic and rational efficiencies of the proposed system, with n-pentane as an ORC working fluid, are calculated as 79.02% and 46.7%, respectively. Effects of variation in different operating parameters as well as Organic working fluid on energetic and exergetic efficiencies have been studied. The coefficient of structural bond analysis demonstrates that the evaporator and cascade condenser operating temperature significantly affects the system performance. The proposed trigeneration system powered by waste heat is independent of the grid supply; however, a stand-alone vapor compression refrigeration system requires about 19.15 kWe to meet the equivalent cooling demand. The decision of selection between the stand-alone system and the proposed trigeneration system is influenced by the compressor capacity of stand-alone vapor compression refrigeration system, cost of unit electricity, compressor runtime, cost of Organic Rankine Cycle power block, and cost of vapor absorption system. Based on the condition of equality of the annualized cost of the stand-alone system and proposed trigeneration system, a methodology for selection between these two configurations, called selection diagram, is also presented in this paper. The selection diagram gives quick suggestion about the optimal configuration at the initial design stage. The economic analysis reveals that the simple payback period and breakeven point for the proposed hybrid system are 6.2 years and 4.9 years, respectively.

  • thermo economic analysis and selection of working fluid for solar Organic Rankine Cycle
    Applied Thermal Engineering, 2016
    Co-Authors: Nishith B Desai, Santanu Bandyopadhyay
    Abstract:

    Abstract Organic Rankine Cycle (ORC), powered by line-focusing concentrating solar collectors (parabolic trough collector and linear Fresnel reflector), is a promising option for modular scale. ORC based power block, with dry working fluids, offers higher design and part-load efficiencies compared to steam Rankine Cycle (SRC) in small-medium scale, with temperature sources up to 400 °C. However, the cost of ORC power block is higher compared to the SRC power block. Similarly, parabolic trough collector (PTC) system has higher optical efficiency and higher cost compared to linear Fresnel reflector (LFR) system. The thermodynamic efficiencies and power block costs also vary with working fluids of the Rankine Cycle. In this paper, thermo-economic comparisons of Organic Rankine and steam Rankine Cycles powered by line-focusing concentrating solar collectors are reported. A simple selection methodology, based on thermo-economic analysis, and a comparison diagram for working fluids of power generating Cycles are also proposed. Concentrating solar power plants with any collector technology and any power generating Cycle can be compared using the proposed methodology.

Ibrahim Dince - One of the best experts on this subject based on the ideXlab platform.

  • exergy and exergoeconomic analyses and optimization of geothermal Organic Rankine Cycle
    Applied Thermal Engineering, 2013
    Co-Authors: Rami Salah Elemam, Ibrahim Dince
    Abstract:

    Abstract This paper presents thermodynamic and economic analyses on a novel-type geothermal regenerative Organic Rankine Cycle based on both energy and exergy concepts. An optimization study is also performed based on the heat exchangers total surface area parameter. Parametric studies are performed to investigate the effect of operating parameters, and their effects on the system energetic and exergetic efficiencies and economic parameters are investigated. The energy and exergy efficiency values are found to be 16.37% and 48.8%, respectively, for optimum operating conditions at a reasonable rejection temperature range of the geothermal water from 78.49 °C to 116.2 °C. The mass flow rates of the Organic fluid, cooling water and provided geothermal water are calculated for a net out power of 5 MW e .

  • comparative performance analysis of low temperature Organic Rankine Cycle orc using pure and zeotropic working fluids
    Applied Thermal Engineering, 2013
    Co-Authors: S Aghahosseini, Ibrahim Dince
    Abstract:

    In this paper, a comprehensive thermodynamic analysis of the low-grade heat source Organic Rankine Cycle (ORC) is conducted and the Cycle performance is analyzed and compared for different pure and zeotropic-mixture working fluids. The comparative performance evaluation of the Cycle using a combined energy and exergy analysis is carried out by sensitivity assessment of the Cycle certain operating parameters such as efficiency, flow rate, irreversibility, and heat input requirement at various temperatures and pressures. The environmental characteristics of the working fluids such as toxicity, flammability, ODP and GWP are studied and the Cycle CO2 emission is compared with different fuel combustion systems. R123, R245fa, R600a, R134a, R407c, and R404a are considered as the potential working fluids. Results from this analysis provide valuable insight into selection of the most suitable working fluids for power generating application at different operating conditions with a minimal environmental impact.

Bhavesh Patel - One of the best experts on this subject based on the ideXlab platform.

  • optimization of waste heat based Organic Rankine Cycle powered cascaded vapor compression absorption refrigeration system
    Energy Conversion and Management, 2017
    Co-Authors: Bhavesh Patel, Nishith B Desai, Surendra Singh Kachhwaha
    Abstract:

    Abstract In this paper, the thermo-economic optimization of the waste heat based Organic Rankine Cycle powered cascaded vapor compression-absorption refrigeration system is presented. Organic Rankine Cycle with dry Organic working fluid is used as a power generating Cycle to provide input to the vapor compression refrigeration system. Moreover, the high temperature Organic working fluid at the expander outlet is used to supply thermal need of the vapor absorption refrigeration system. The present system achieves low temperature cooling efficiently. However, initial capital cost and complexity are the practical limitations for the present system. The energetic efficiency of the present system for only cooling mode and cogeneration mode (cooling and heating) are calculated to be 22.3% and 79%, respectively. It may be noted that the extra heat available, apart from the thermal energy requirement of the vapor absorption system, is taken as process heat in the cogeneration mode. The simple payback period and break-even point are calculated (for the base case) to be 5.26 years and 4.22 years, respectively. The system size and annualized cost are optimized, using nonlinear programming based on conjugated directions method, to make the system potentially attractive for the industrial sector. Optimization results reveal that the annualized cost of the present system is decreased by about 12% compared to the base case. Moreover, the simple payback period and break-even point are reduced to 4.50 years and 3.48 years, respectively. The results of comparative economic study, between the present and stand-alone vapor compression refrigeration systems, show that the higher value of electricity price and the lower value of discount rate are favorable for the selection of the present system.

  • thermo economic analysis of a novel Organic Rankine Cycle integrated cascaded vapor compression absorption system
    Journal of Cleaner Production, 2017
    Co-Authors: Bhavesh Patel, Nishith B Desai, Surendra Singh Kachhwaha, Vaibhav Jain, Nanji J Hadia
    Abstract:

    Abstract Integration of thermal systems improves the energy efficiency and reduces the carbon emissions. In this paper, a novel trigeneration system, which integrates the Organic Rankine Cycle and vapor compression–absorption cascade refrigeration Cycle is proposed. The cascade refrigeration system combines the advantages of the conventional stand-alone vapor compression system and vapor absorption refrigeration system. The energetic and rational efficiencies of the proposed system, with n-pentane as an ORC working fluid, are calculated as 79.02% and 46.7%, respectively. Effects of variation in different operating parameters as well as Organic working fluid on energetic and exergetic efficiencies have been studied. The coefficient of structural bond analysis demonstrates that the evaporator and cascade condenser operating temperature significantly affects the system performance. The proposed trigeneration system powered by waste heat is independent of the grid supply; however, a stand-alone vapor compression refrigeration system requires about 19.15 kWe to meet the equivalent cooling demand. The decision of selection between the stand-alone system and the proposed trigeneration system is influenced by the compressor capacity of stand-alone vapor compression refrigeration system, cost of unit electricity, compressor runtime, cost of Organic Rankine Cycle power block, and cost of vapor absorption system. Based on the condition of equality of the annualized cost of the stand-alone system and proposed trigeneration system, a methodology for selection between these two configurations, called selection diagram, is also presented in this paper. The selection diagram gives quick suggestion about the optimal configuration at the initial design stage. The economic analysis reveals that the simple payback period and breakeven point for the proposed hybrid system are 6.2 years and 4.9 years, respectively.

Surendra Singh Kachhwaha - One of the best experts on this subject based on the ideXlab platform.

  • optimization of waste heat based Organic Rankine Cycle powered cascaded vapor compression absorption refrigeration system
    Energy Conversion and Management, 2017
    Co-Authors: Bhavesh Patel, Nishith B Desai, Surendra Singh Kachhwaha
    Abstract:

    Abstract In this paper, the thermo-economic optimization of the waste heat based Organic Rankine Cycle powered cascaded vapor compression-absorption refrigeration system is presented. Organic Rankine Cycle with dry Organic working fluid is used as a power generating Cycle to provide input to the vapor compression refrigeration system. Moreover, the high temperature Organic working fluid at the expander outlet is used to supply thermal need of the vapor absorption refrigeration system. The present system achieves low temperature cooling efficiently. However, initial capital cost and complexity are the practical limitations for the present system. The energetic efficiency of the present system for only cooling mode and cogeneration mode (cooling and heating) are calculated to be 22.3% and 79%, respectively. It may be noted that the extra heat available, apart from the thermal energy requirement of the vapor absorption system, is taken as process heat in the cogeneration mode. The simple payback period and break-even point are calculated (for the base case) to be 5.26 years and 4.22 years, respectively. The system size and annualized cost are optimized, using nonlinear programming based on conjugated directions method, to make the system potentially attractive for the industrial sector. Optimization results reveal that the annualized cost of the present system is decreased by about 12% compared to the base case. Moreover, the simple payback period and break-even point are reduced to 4.50 years and 3.48 years, respectively. The results of comparative economic study, between the present and stand-alone vapor compression refrigeration systems, show that the higher value of electricity price and the lower value of discount rate are favorable for the selection of the present system.

  • thermo economic analysis of a novel Organic Rankine Cycle integrated cascaded vapor compression absorption system
    Journal of Cleaner Production, 2017
    Co-Authors: Bhavesh Patel, Nishith B Desai, Surendra Singh Kachhwaha, Vaibhav Jain, Nanji J Hadia
    Abstract:

    Abstract Integration of thermal systems improves the energy efficiency and reduces the carbon emissions. In this paper, a novel trigeneration system, which integrates the Organic Rankine Cycle and vapor compression–absorption cascade refrigeration Cycle is proposed. The cascade refrigeration system combines the advantages of the conventional stand-alone vapor compression system and vapor absorption refrigeration system. The energetic and rational efficiencies of the proposed system, with n-pentane as an ORC working fluid, are calculated as 79.02% and 46.7%, respectively. Effects of variation in different operating parameters as well as Organic working fluid on energetic and exergetic efficiencies have been studied. The coefficient of structural bond analysis demonstrates that the evaporator and cascade condenser operating temperature significantly affects the system performance. The proposed trigeneration system powered by waste heat is independent of the grid supply; however, a stand-alone vapor compression refrigeration system requires about 19.15 kWe to meet the equivalent cooling demand. The decision of selection between the stand-alone system and the proposed trigeneration system is influenced by the compressor capacity of stand-alone vapor compression refrigeration system, cost of unit electricity, compressor runtime, cost of Organic Rankine Cycle power block, and cost of vapor absorption system. Based on the condition of equality of the annualized cost of the stand-alone system and proposed trigeneration system, a methodology for selection between these two configurations, called selection diagram, is also presented in this paper. The selection diagram gives quick suggestion about the optimal configuration at the initial design stage. The economic analysis reveals that the simple payback period and breakeven point for the proposed hybrid system are 6.2 years and 4.9 years, respectively.

H Spliethoff - One of the best experts on this subject based on the ideXlab platform.

  • experimental study of an orc Organic Rankine Cycle and analysis of r1233zd e as a drop in replacement for r245fa for low temperature heat utilization
    Energy, 2016
    Co-Authors: S Eyere, C Wieland, A Vandersickel, H Spliethoff
    Abstract:

    The Organic Rankine Cycle can be applied to convert low temperature heat to electrical power using Organic working fluids. Recently, a new generation of working fluids has been introduced with almost no Ozone Depletion Potential and significantly smaller Global Warming Potential, compared to currently used refrigerants. R1233zd-E is a promising low-GWP (global warming potential) alternative to R245fa, a widely used fluid in ORC (Organic Rankine Cycle) systems. This paper analyzes the applicability of the new fluid as drop-in replacement for R245fa in existing systems and compares system parameters such as Cycle efficiency and power output. To this end, the influence of the process parameters mass-flow rate, condensation temperature and expander rotational speed is investigated experimentally for both fluids. The test rig used has an electrical heater as a heat source and a scroll compressor as an expander. As a conclusion, R1233zd-E can be used as a substitute for R245fa in existing ORC systems. In addition to the advantage of having a much smaller GWP, the use of R1233zd-E may lead to higher thermal efficiencies. Comparing the highest achieved thermal efficiency, R1233zd-E performs 6.92% better than R245fa. However, comparing the maximal gross power output, R245fa performs 12.17% better than R1233zd-E.

  • effect and comparison of different working fluids on a two stage Organic Rankine Cycle orc concept
    Applied Thermal Engineering, 2014
    Co-Authors: Dominik Meinel, C Wieland, H Spliethoff
    Abstract:

    This paper presents Aspen Plus (V7.3) simulations of a two-stage Organic Rankine Cycle concept with internal heat recovery. The proposed system is compared to state-of-the-art processes with four different working fluids distinguished by the slope of the saturated vapor curve in the corresponding Tes-diagram. The heat source is defined as exhaust gas (490 C and 1 bar) from an internal combustion engine, which is fired with biogas from a biomass digestion plant. In a first consideration the exhaust gas outlet is constrained to 130 C to stay above the acid dew point (study 1). In a second study the pinch point of the exhaust gas heat exchanger is set to 10 K. For wet and isentropic fluids the thermodynamic efficiencies of the two-stage Cycle exceed the corresponding values of reference processes by up to 2.25%, while the recuperator design benefits dry fluids compared to the two-stage concept.

  • energetic and economic investigation of Organic Rankine Cycle applications
    Applied Thermal Engineering, 2009
    Co-Authors: Andreas Schuster, Sotiriοs Karellas, E Kakaras, H Spliethoff
    Abstract:

    The use of Organic working fluids for the realization of the so called Organic Rankine Cycle (ORC) has been proven to be a promising solution for decentralized combined heat and power production (CHP). The process allows the use of low temperature heat sources, offering an advantageous efficiency in small-scale applications. This is the reason why the number of geothermal and biomass fired power plants based on this technology have been increased within the last years. The favourable characteristics of ORC make them suitable for being integrated in applications like solar desalination with reverse osmosis system, waste heat recovery from biogas digestion plants or micro-CHP systems. In this paper, the state of the art of ORC applications will be presented together with innovative systems which have been simulated in a process simulation environment using experimental data. The results of the simulation like efficiencies, water production rates or achievable electricity production cost will be presented and discussed.