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The Kalina cycle is well-known for its innovative energy conversion optimization, utilizing various working fluids such as butane, freon, isobutane, and pentane to evaluate efficiency and performance. This research explores the interaction of fluids in the Kalina cycle to enhance heat recovery by utilizing heat from road infrastructure. Our research focuses on analyzing thermodynamic intricacies and fluid dynamics to provide insights for improving sustainable energy technologies and enhancing heat utilization in various industrial applications. The performance of working fluids in the Kalina cycle has a notable impact on power generation or consumption, which can differ depending on the equipment configurations. One interesting observation is that certain cycles showed a net energy gain at the turbine, particularly the ammonia cycle running at 75 % working fluid, which generated a total net power of −1030.6048 kW. Two freon cycles were compared in terms of net power output: the pure freon cycle produced −125.493 kW, whereas the freon cycle with 90 % freon generated −375.1616 kW. Finally, the pentane cycle with a 50 % efficiency yielded a net power output of −137.6613 kW. This study offers a thorough understanding of how working fluids perform in the Kalina cycle, which can help improve energy conversion processes and promote sustainable energy solutions.

This study proposes a novel methodology for optimizing the Kalina Cycle System-34, providing new insights into the existing literature on the cycle. The research highlights the cycle's key variables and identifies the most critical parameters that require improvement while proposing a practical and effective optimization method. The effects of parameters on thermal and exergy efficiency were quantified using Taguchi and ANOVA methods. The study focuses on critical parameters such as evaporator outlet temperature, turbine inlet pressure, ammonia concentration, turbine efficiency, and pump efficiency. The optimal values of these parameters were determined within specified ranges. Furthermore, the study employed the L25 orthogonal array to create case scenarios that reduced the computational cost of the Kalina cycle. The best-case scenario was not included in the 25 cases in the orthogonal array, which significantly reduced computational costs. The results showed that the system's thermal efficiency increased to 16.2 %, and exergy efficiency increased to 27.8 %, with the case conditions for the best case being an evaporator outlet temperature of 120 °C, ammonia concentration of 0.9, turbine inlet pressure of 40 bar, turbine efficiency of 0.9, and pump efficiency of 0.8.

ABSTRACTDemand for electricity and cooling is increasing due to population growth, which in turn increases pollution. Renewable energy sources are gaining popularity due to their lower levels of pollution. Resource utilisation efficiency is an important factor in maximising the efficiency of low-temperature heat sources. In this study, a vapour absorption cooling cycle and a Kalina power cycle were merged. At the economiser, heat is recovered from the heat exchanger and divided into two basic solution streams. The high-pressure flow passes through the boiler evaporator to produce wet steam, while another stream is throttled to an intermediate pressure. The thermal efficiency of the cycle improves with increasing separator temperature, separator pressure, concentration, and heat recovery temperature, but there is an optimal separator temperature for resource utilisation capacity. Increasing separator pressure and heat recovery temperatures improves resource utilisation efficiency. The proposed cycle has a better temperature match in the heating process. The resource utilisation efficiency of the present cycle is 31.13%, which is 90.63% higher than the reference study.

This research presents a novel, eco-efficient hybrid system designed for the simultaneous production of power, oxygen, and methanol. It utilizes energy from coke plants and incorporates state-of-the-art waste heat recovery processes (WHRPs). The system effectively merges electricity and methanol production with WHRPs, improving both environmental sustainability and economic feasibility in industrial energy transformation. It consists of a fuel reforming and combustion unit, a waste heat recovery unit, a unit for hydrogen gas production through water electrolysis, and a methanol synthesis module. This configuration enables the production of 12.72 MW of electricity, 0.51 kg/s of oxygen, and 0.53 kg/s of methanol, achieving an energy productivity of 46.8 % and an exergy efficiency of 85.13 %. The economic analysis indicates competitive costs of $0.099 per kWh for electricity and $0.56 per kg for methanol. The system surpasses current technologies in thermodynamic efficiency, operational and product costs, and reduced CO2 emissions, demonstrating its potential as a sustainable and economically sound solution for industrial energy challenges. It supports global sustainability initiatives and fits within the circular economy concept.

This paper presents a novel multigeneration system that utilizes ammonia as the primary fuel for marine vessel applications. The system integrates and thermodynamically investigates various components, including solid oxide fuel cells (SOFC), gas turbines (GT), proton exchange membrane fuel cells (PEMFC), organic Rankine cycle (ORC), steam Rankine cycle (SRC), Kalina cycle (KC), and waste heat boiler (WHB). The primary objective of the integration strategy is to recover waste heat from the SOFC and harness the power generated by the PEMFC, resulting in improved thermal efficiency, reduced vessel startup time, and enhanced environmental sustainability. Mathematical models have been developed to facilitate the examination of the system’s thermodynamic performance. Comprehensive thermodynamic modeling employing energy and exergy analysis methods is employed to evaluate the effectiveness of both the proposed system and its subsystem. Moreover, the exergy destruction of all system components and integrated subsystems is quantified to provide a comprehensive understanding of their impact. The projected system exhibits an energy efficiency of 60.69% and an exergy efficiency of 57.50%. The waste heat recovery combined systems generate 1634.46 kW, accounting for 30.07% of the total power output of the integrated SOFC system. The performance of the system was analyzed through parametric studies, where different values of current density, distribution ratio (β) (from 0.1–0.4), and δ parameter (from 0–0.5) were examined. The findings revealed that increasing the current density led to a decrease in energy and exergy efficiency, despite an overall rise in the power output of the cogeneration system. Moreover, the waste heat boiler is capable of providing 1081 kg/h of superheated steam at 162 °C and 405 kPa to fulfill the heating requirements of marine lubricating oil, devices, and accommodation for seafarers on board the ship.

This article introduces a novel multiple-cycle generation system for efficient heat recovery at high and low temperatures. The system is modeled and optimized using the M2EP analysis method (mass, energy, exergy, and performance) and the particle swarm optimization algorithm. The multigeneration system produces electricity, cold, domestic hot water, and biogas by utilizing Kalina cycles, diffusion–absorption refrigeration machines, and high-performance heat exchangers by harnessing waste heat from cement kiln exhaust gases. The Kalina cycle is employed for electricity generation, wherein the H2O+NH3 mixture, heated by hot water, circulates through heat exchangers. Downstream of the Kalina cycle, the refrigeration machine generates cold by evaporating the strong solution of the H2O+NH3 mixture. Hydrogen circulates in the diffusion–absorption refrigerator (DAR) circuit, facilitating the exchange between the evaporator and the absorber. The domestic hot water and biogas production systems operate at lower temperatures (around 45 °C). The simulation results for the Kalina cycle indicate an electrical energy production of 2565.03 kW, with a release of usable energy (residual gases) estimated at 7368.20 kW and a thermal efficiency of 22.15%. Exergy destruction is highest at heat exchanger 1, accounting for 26% of the total. A coefficient of performance of 0.268 and an evaporator temperature of 10.57 °C were obtained for the DAR cycle. The absorber contributes the most to energy exchanges, comprising 37% of the entire circuit. Summarizing the potential for valorizing waste heat from cement kilns, this article lays the foundation for future research.

The present study introduces a novel tri-generation system that is highly efficient and cost-effective, employing a supercritical CO2 (sCO2) Brayton cycle as the primary mover and harnessing the cooling potential from liquefied natural gas (LNG) as a heat sink. This innovative system simultaneously provides electricity, cooling, and hydrogen. By capitalizing on the substantial temperature difference between the high-temperature sCO2 power cycle and the low-temperature LNG cold source, an integrated combination of the Kalina cycle (KC) and organic Rankine cycle (ORC) is utilized. Additionally, the system incorporates a proton exchange membrane electrolyzer (PEME) and an absorption refrigeration cycle (ARC) to create a highly efficient trigeneration system. The system is rigorously evaluated through energy, exergy, and exergoeconomic analyses, which are critical for assessing performance. Additionally, this study conducts a parametric investigation to elucidate the impact of key parameters on system performance. Furthermore, optimization is performed using a genetic algorithm (GA), with the objective of maximizing energy and exergy efficiencies or minimizing the overall product cost. Results from the baseline scenario demonstrate impressive energy and exergy efficiencies of 54.38 % and 59.46 % respectively, along with a low total product unit cost of 11.642 ($/GJ), outperforming existing benchmarks in the literature. The system also provides substantial net power output, cooling capacity, and hydrogen production rates of 276.71 MW, 60.19 MW, and 176.25 kg/h, respectively. This combination of high performance and cost-effectiveness makes the proposed system a versatile choice, underscoring its significance in sustainable and environmentally friendly energy solutions.

This paper presents an innovative trigeneration system designed for efficient power, cooling, and hydrogen production. It combines a supercritical carbon dioxide (sCO2) power cycle with a Kalina cycle (KC) and an ammonia-water-based absorption refrigeration cycle (ARC), all integrated with a PEM electrolyzer (PEME) unit. The system optimally utilizes waste heat from the sCO2 power cycle to enhance power generation through the KC and provide cooling via the ARC. Additionally, it leverages the PEME system and KC-generated power for eco-friendly hydrogen production. Mathematical models, thermodynamic, and exergoeconomic analyses were performed, including parametric studies, optimization, and comparative analyses. The results indicate that the reactor experiences the highest exergy destruction rate, while components in the bottoming cycles exhibit lower exergy destruction. From an exergoeconomic perspective, the reactor and sCO2 turbine are ranked as the first and second most significant components. Under the optimal conditions, the system achieved a 9.76 % increase in exergy efficiency and a 6.63 % reduction in total product unit cost. The system also provides substantial net power output, cooling capacity, and hydrogen production rates of 261.74 MW, 123.95 MW, and 176.328 kg/h, respectively. These findings highlight the system's significant thermodynamic and economic advantages, making it a promising choice for diverse user needs.

In this study, renewable energy sources including a high-temperature solar parabolic trough collector and geothermal water integrated with a modified Kalina cycle, a combined ORC-EJR cycle, an electrolyzer, an RO desalination unit, and a domestic water heater. SiO2 and TiO2 nanoparticles dissolved in Therminol VP1 are applied as the working fluid of the solar collector. A comparative analysis of introduced working fluids is performed from energy, exergy as well as cost analysis point of view to evaluate their efficiencies. Solar irradiation, ambient temperature, and collector inlet temperature were the parameters investigated to discover their effects on energy and exergy efficiency, solar collector outlet temperature, hydrogen production rate, and freshwater production rate. The highest generated outlet temperature of the solar collector outlet was 693.8 K obtained by Therminol VP1/SiO2 nanofluid. The maximum energy and exergy efficiencies of the proposed system were 36.69 % and 17.76 %, respectively. Moreover, it is found that by increasing the solar collector inlet temperature, the hydrogen production rate decreases while the water production rate increases.

In this proposed study, hydrogen and power generation by low-temperature geothermal energy supported Kalina cycle is thermodynamically investigated with an energy and exergy efficiencies approaches. This combined plant includes a Kalina cycle and a PEM electrolysis for power and hydrogen generation. The key purpose of this paper is to generate power and hydrogen in an environmentally benign way. Furthermore, environmental impact analysis is discussed to investigate the carbon dioxide emission that will be released if the power and amount of hydrogen obtained are produced with natural gas. As coming to the examination results, the energy and exergy performance of the overall plant 7.94% and 37.64%, respectively. Also, the net power and hydrogen production rates are computed as 100.5 kW and 0.0001191 kgs-1.

In this study, it is proposed to generate electrical energy by recovering the waste heat of an annealing furnace (AF) in an iron and steel plant using combined cycles such as steam Rankine cycle (SRC), organic Rankine cycle (ORC), Kalina cycle (KC) and transcritical CO2 cycle (t-CO2). Instead of releasing the waste heat into the atmosphere, the waste heat recovery system (WHRS) discharges the waste heat into the plant’s low-temperature oxygen line for the first time, achieving a lower temperature and pressure in the condenser than conventional systems. The waste heat of the flue gas (FG) with a temperature of 1093.15 K from the reheat furnace was evaluated using four different cycles. To maximize power generation, the SRC input temperature of the proposed system was studied parametrically. The cycles were analyzed based on thermal efficiency and net output power. The difference in SRC inlet temperature is 221.6 K for maximum power output. The proposed system currently has a thermal efficiency and total power output of 0.19 and 596.6 kW, respectively. As an environmental impact, an emission reduction potential of 23.16 tons/day was achieved. In addition, the minimum power generation cost of the proposed system is $0.1972 per kWh.

In this study, the partial alteration of fuel consumption of combined cycle power plants was investigated and analyzed using an innovative model. This system is applicable using the fuel derived from the biomass gasification process. For this purpose, energy modeling of an advanced gasification system to supply a share of the gas fuel was fulfilled. The results demonstrated that by considering the reasonable capacities for the design, up to 10 % of natural gas fuel could be replaced with syngas. In addition, heat recovery of the plant stack in the Kalina low-temperature cycle enhanced the total efficiency by up to 1.7 %. Therefore, the competitive advantage of the proposed cycle was enhanced compared to conventional power generation systems. A parametric study of the components affecting the integrated cycle performance including alternative biomass fuels, moisture content of biomass fuel, steam-to-biomass ratio, and equivalence ratio of the gasifier was performed, and the permissible values of each factor were obtained. Thus, by utilizing the proposed approach, it is possible to gradually substitute the consumed fossil fuels of power plants with renewable resources to achieve the objectives of sustainable energy development.

This paper provides an overview of various studies on the Kalina cycle and their applications. The century-old Rankine cycle is the foundation for modern power facilities. However, a modified Rankine cycle known as the Kalina cycle has proven to be more efficient than the conventional Rankine cycle and may be able to provide the additional power required for medium- and low-temperature sources and residual heat recovery. Comparing the effectiveness of the Kalina cycle and the Rankine cycle in converting electrical energy from low-temperature sources, Kalina cycle seems more suitable for low temperature power generation.

Abstract This study has attempted to compare two thermodynamic cascade cycles, which in this paper are presented as Systems A and B. System A was consisted of a steam Rankine cycle (SRC) as a top cycle and an organic Rankine cycle (ORC) as a bottom cycle. System B was consisted of the same SRC as the top cycle and a Kalina cycle as the bottom cycle. The comparison of both systems has been made by changing a number of parameters. The chosen parameters for this comparison were bottom cycle mass flow rate, aperture area of the collector, top cycle condensing pressure, and bottom cycle turbine inlet and outlet pressures. Also, a short economic evaluation has been made between two proposed cascade cycles (Systems A and B). The result indicated that the Kalina cycle shows superiority over the ORC as the bottom cycle in a solar‐driven SRC. Furthermore, it was determined that the most effective parameters on the overall efficiency of the systems are the condensing pressure of the top cycle and the outlet pressure of the bottom cycle turbine. Also, among the chosen parameters, the outlet pressure of the bottom cycle turbine had the highest effect on the efficiency of the bottom cycles. Considering the economic aspect, the results showed that the levelized costs of energy for both systems are quite equal at 0.011 ($/kWh).

Abstract This study investigates a coupled system combined by a LiBr/H2O absorption refrigeration cycle and a Kalina cycle, to recover waste heat from a hydrate-based CO2 capture process. The optimal system operation has been obtained. Payback time, Return on investment, Net present value and Discounted cash flow rate of return are selected as the evaluation indicators for a comprehensive economic analysis. Cash flow patterns are obtained for different discounted interest rates and electricity prices. Exergy analysis is conducted and the exergy loss of each component is calculated. Results show that in comparison with the individual Kalina cycle, the net electricity generation is increased by around 45%. The highest thermal efficiency of this coupled system is 16.78%. Payment balance can be achieved with a payback time of 6 years. The purchase price of heat exchanger occupies the largest capital investment. Exergy efficiency of this system is obtained as 36.89%. Major system irreversibility occurs in heat transfer processes of heat exchangers and the largest exergy loss is found in generators of both subcycles. Reducing the heat transfer irreversibility and the size of heat exchangers are greatly encouraged in future efforts.

In the present research, a Kalina cycle has been analyzed from the energy, exergy, economic and exergoeconomic points of view. In this cycle, the water-ammonia solution is used as the working fluid. Firstly, the mass balance, energy, and exergy equations are solved, then the initial cost and exergy destruction cost have been calculated using the cost balance equations in different components. Finally, the optimization of solar Kalina's performance in terms of target functions, i.e., total cost rate and exergy efficiency, has been performed. To this end, a relationship between design parameters and target functions is derived using the neural network algorithm; then, the multiobjective optimization of the cycle is performed using the particle swarm optimization (PSO) algorithm. The results show that total work, net irreversibility, and total exergy efficiency in the base case are 296.2kW, 3671kW, and 0.0738, respectively. The exergoeconomic analysis indicates that the total cost rate was 366$h, and it was found that the solar collector and Kalina evaporator have respectively the maximum cost rate. The parametric analysis has been performed in terms of energy, exergy, and exergoeconomic to examine the effect of turbine's inlet temperature and pressure, and ammonia content on the cycle performance. The optimization results indicate that exergy efficiency and total cost rate are 0.08824, and 318.58$h, respectively. This represents an 19.5% increase in the exergy and a 12.95% reduction in cost rate compared to the base case.

This study presents the energy, exergy, and economic evaluation of recovering energy from a modified Kalina power-cooling system to provide heating and hydrogen. An ORC is employed to use the waste heat of the Kalina cycle, and the generated power is transmitted to a PEM electrolyzer for hydrogen production. Furthermore, the waste heat of the separator outlet is recovered through a new heat exchanger to provide heating. The results show that the proposed system can produce 317 kW power, 714.7 kW cooling, 50.3 kW heating, and 4.491 kg/h hydrogen. Moreover, the exergoeconomic analysis indicates that the PEM electrolyzer, the cascade heat exchanger, and the vapor generator have the highest cost rate among the system components. Additionally, a parametric study was performed on the system to investigate the variation of some key parameters, including the maximum operating pressure, separator II pressure, ammonia mass fraction in a basic solution, and pinch point temperature difference in the cascade heat exchanger for the thermodynamic and economic performance of the system.

Refrigeration and power are the most desirable requirements in commercial places and offices. Goswami cycle is one of the solutions to generate power and refrigeration simultaneously with less pollution. In the Goswami cycle, the power and refrigeration streams are connected in series, the refrigeration output is limited in a series arrangement. In the present study, parallel streams are proposed to improve the performance of the cycle. In the Goswami cycle, the saturated vapour is enriched for power and refrigeration. In the present study, the saturated vapour is used for the power generation, the saturated liquid is flashed to the intermediate pressure, and the generated wet vapours are enriched for refrigeration processes. It is observed that power generation is increasing with an increase in dryness fraction and the fall in basic solution concentration, whereas the refrigeration effect is growing with the fall in dryness fraction and increase in basic solution concentration. The modified cycle is consistently generating higher output than the conventional cycle. The thermal efficiency of the Kalina flash cycle is 29.05% higher and the exergy efficiency is 5.61% lesser than the Goswami cycle.

In recent years, attentions are focused on the application of cutting-edge reactors to utilize the remarkable virtues such as safety and also higher thermal efficiency. Sodium-cooled fast reactors (SFRs) are midst the promising types of fourth generation reactors for their non-reacting behavior and packed configurations, which are considered as heat source of various thermodynamic systems. Accordingly, nitrogen Brayton cycle could be devised as power conversion system (PCS) of the mentioned sodium cooled reactors, due to its simple arrangement. In present study, proposing the topping system of nitrogen Brayton cycle as a power generation system which is driven by the sodium reactor system, Kalina and heat pump cycles, as bottoming cycles, were designed to increase the performance of the overall system by integration with topping system. Subsequently, energy, exergy and exergoeconomic analyses were carried out to examine the reliability of the proposed system. The results displayed that under operating conditions, thermal efficiency, exergetic efficiency of the proposed system are 34% and 62%, respectively. Furthermore, using the exergy point of view, it was revealed that steam generator heat exchanger, SGHX, is the foremost cause of exergy destruction. Also, in order to attain an inclusive insight over the system, a parametric analysis was conducted. Therefore, investigating the influence of alterations in key features of the overall cycle, several optimum working conditions, such as optimal basic concentration of ammonia in Kalina cycle, optimal turbines (I&II) expansion ratio and low-pressure compressor pressure ratio etc., were derived.

The roller kiln is characterized by significant heat losses mainly caused by flue gas and cooling gas accounting for 70%. In this study, four novel power cycles including a basic organic Rankine cycle (BORC), a regenerative organic Rankine cycle (RORC), a Kalina cycle11 (KC11) and a Kalina cycle 34 (KC34) with the parallel double-evaporator (PD) configuration are proposed for dual-level waste heat recovery for a roller kiln. To identify the superiority system, the recommended power cycles are assessed and compared from an integrated thermodynamic and economic perspective. The impacts of the basic operating parameters on net power output, exergy efficiency, electricity production cost and savings to investment ratio are discussed. Meanwhile, the single-, bi- and three-objective optimizations are conducted and the optimal solutions are compared. The results indicated that for the considered optimization models, PDKC34 achieved the highest net power output of 211.06–224.45​ kW and thermal efficiency of 20.02–21.20%, PDBORC had the best economic performance on electricity production cost of 0.0875–0.0932 $/kWh, payback period of 5.709–6.210 year and savings to investment ratio of 2.191–2.335 while PDRORC with R-141b possessed the best exergy efficiency of 45.11–49.17%. On the whole, the four thermodynamic cycles contributed to the best thermodynamic performance in the maximizing net power output model while these had the best economic performance in the minimum EPC model. Besides, the evaporation unit had the highest impact on exergy destruction and total investment cost among all components for the studied optimization models.

In this investigation, a solar-driven multi-generation plant is developed and studied through exergy assessment. The developed integrated system is designed to provide power, cooling, freshwater, and hot water for an industrial complex. The designed layout consists of solar parabolic trough collectors as the main driver which can provide the driving temperature of 220 °C at its maximum output, a combination of Kalina cycle and ejector refrigeration to produce cooling load and power for the industrial complex, and multi-effect distillation unit to generate freshwater. Exergy assessment shows that collectors are the most destructive equipment in the designed layout. The exergy efficiency of the solar parabolic trough collectors reaches to 49.36%. The total exergy efficiency of the presented system achieves up to 25.92%. The designed system provides 32.27 kW of power, 156.3 kW of cooling, 4.907 m3/h of freshwater, and 1.449 m3/h of hot water at 61.4 °C. Additional assessments show that vapor generator pressure is a key factor on the output performance of the presented system. It has been shown that the total exergy efficiency of the system decreases by increasing the vapor generator pressure. The economic assessment illustrates that the investment return period and the prime cost of the product are 3.958 years and 1.773 US$/m3 freshwater, respectively.

A novel strategy is presented for the utilization of the excess steam released into the atmosphere from the vent valve of a geothermal power plant. In particular, three possible approaches are considered: dry-steam cycle, binary cycle, and Kalina cycle. Thermodynamic models of these different power cycles are defined accordingly. The simulations are carried out using Aspen HYSYS®, used to solve the corresponding mass and energy balance equations. The feasibility and advantages of the different approaches are discussed from different points of view, i.e., energy, net power, and overall efficiency. Moreover, exergy analysis is used to identify the location, magnitude, and origin of thermodynamic inefficiencies. Economic aspects are also considered in terms of electricity or levelized electricity generating cost (LEGC) for the three considered cycles. Performances are quantified in terms of Capacity Factor (CF), the ratio between the actual power produced by the generator in a given period and the maximum output power that can be achieved according to the design capacity. The environmental impact is also considered.

This study proposes a design of a trigeneration plant for the usage of Periwinkle Lifestyle Estate in Lagos State Nigeria. The proposed system would provide electricity, heating and freshwater requirements for residential buildings from a renewable energy source. Concentrated photovoltaic solar thermal (CPV/T) collector is used to generate the electricity and provides the required amount of thermal energy to the multistage flash desalination plant and Kalina cycle due to its high electrical and thermal effectiveness. The EES is used to model the tri-generation system by solving the governing equations with an interconnected structure, while TRNSYS and HOMER software was also used to collect the solar data for the case study area. The combined trigeneration structure can produce 0.6412 kg/s of freshwater, 1520.25 kW of electricity generation, and 91.57 kW of heat required for the district heating application, for the usage of Periwinkle lifestyle estate Lagos State Nigeria. The designed system can serve as an alternative to producing high-quality freshwater for drinking and irrigation, reliable and steady electricity and heating services during the winter season, without pollution.

Natural gas-fired combined cycle plants are nowadays one of the most efficient and environmentally friendly energy complexes. High energy efficiency and low specific emissions are achieved primarily due to the high average integral temperature of heat supply in the Brayton–Rankine cycle. In this case, the main sources of energy losses are heat losses in the condenser of the steam turbine plant and heat losses with the exhaust gases of the waste heat boiler. This work is related to the analysis of the thermodynamic and economic effects in the transition from binary to trinary cycles, in which, in addition to the gas and steam–water cycles, there is an additional cycle with a low-boiling coolant. A method for the feasibility study of a waste heat recovery unit for trinary plants is proposed. The schematic and design solutions described will ensure the increased energy and economic performance of combined cycle power plants. Based on the results of the thermodynamic optimization of the structure and parameters of thermal schemes, it was found that the use of the organic Rankine cycle with R236ea freon for the utilization of the low-grade heat of a trinary plant’s exhaust gases operating from a GTE-160 gas turbine makes it possible to achieve a net electrical efficiency of 51.3%, which is a 0.4% higher efficiency for a double-circuit combined cycle gas turbine plant and a 2.1% higher efficiency for a single-circuit cycle with similar initial parameters. On the basis of the conducted feasibility study, the parameters and characteristics of the heat exchangers of the regenerative system of the waste heat recovery unit are substantiated. The use of plain fin-and-tube heat exchangers in the regenerative system of the utilization cycle is the most promising solution. It was found that the level of allowable pressure loss in the regenerator of 10 kPa and the degree of regeneration of 80% allow for maximum economic efficiency of the waste heat recovery unit.

This study aims at the proposal of a novel waste heat recovery system to recover the waste heat of the gas turbine cycle. Thus, a novel power generation system is devised based on the gas turbine cycle and Kalian cycle. To evaluate the performance of the system, the energy, exergy, and environmental analysis is carried out. Also, the sensitivity analysis is performed to assess the effect of different parameters on the system’s performance criteria, including net output power, thermal efficiency, exergetic efficiency, and Levelized total emission. Using genetic algorithm, the optimization process is performed in different scenarios. Based on the optimization results, the TEOD (Thermal efficiency optimization design) mode can result in the optimum performance as it leads to increment of thermal efficiency and exergy efficiency by 46.11% and 47.24%, respectively. Also, the LTE value is decreased to 60113 kg kW−1. Among all components of the system, the combustion chamber is contributed to the highest value of the exergy destruction rate by 27141 kW, where the exergy destruction rate of the Kalina subsystem is followed the combustion chamber by the value of 6932 kW.

This work presents energy, exergy, and thermoeconomic analysis of an advanced Kalina power generation system. In every key component of the proposed system, cost-balance and auxiliary equations are typically developed which is solved efficiently through MATLAB coding. The cost-effectiveness of the entire system is assessed by the determination of thermoeconomic variables for the individual components. The energy analysis of the advanced Kalina cycle system (AKCS) proves marginal improvement to the medium temperature heat recovery Kalina cycle system (KCS). The relative cost difference in HE5, turbine, HE6, and condenser are quite larger than other components of AKCS emphasizing more focus on these components is required. The low values of HE5 (11.77 %) and pump1, P1(13.33 %) insist that the performance of these two components has to be improved by capital investment into a better and improved design. The energy performance maximizes at operating conditions of 45 bar turbine inlet pressure, 72–74 °C separator inlet temperature, 0.94 ammonia concentration at the condenser and 0.83 separator inlet concentration. The thermoeconomic performance minimizes at operating conditions of 30 bar turbine inlet pressure, 68 °C separator inlet temperature, 0.89 ammonia concentration at the condenser and 0.79 separator inlet concentration.

In this paper, a novel thermal driven supercharging system for downsizing of a turbocharged diesel engine is proposed. Furthermore, Kalina cycle has been used as waste heat recovery system to run the mounted supercharging system. The waste heat of air in engine exhaust and intake pipes is converted to cooling and mechanical power by Kalina cycle. The mechanical power produced by Kalina cycle is transferred to an air compressor to charge extra air to the engine for generating more power. This feature can be used for downsizing the turbo-charged heavy duty diesel engine. In addition, the heat rejected from engine intercooler is transferred to Kalina cycle vapor generator component, and part of engine exhaust waste heat is also used for superheating Kalina working fluid before entering engine. Then, first and second law analysis are performed to assess the operation of the engine in different conditions. Moreover, an economic model is provided for the Kalina cycle which is added to engine as supplementary component. Finally, simple payback and Net present value methods are used for economic evaluation of the added supplementary system. According to the results, mounting the novel waste heat driven air charging system has resulted in increment of air mass flow rate which leads to extra power generation (between 9 kW and 25 kW). The payback period and profitability index of the project are approximately 3.81 year and 1.26, consecutively.

As an alternative to the conventional steam Rankine Cycle, Kalina Cycle has witnessed a growing interest over the past years for high-temperature applications (A working fluid temperature of 500°C at the turbine inlet). However, the possibility of implementing an additional multi-phase expander on the weak ammonia-water solution loop of the Kalina cycle was hardly analyzed in the available literatures. In this research, two novel Kalina cycles (Kalina cycle-12A and Kalina cycle-12B) have been presented by integrating a multi-phase expander in addition to the turbine installed downstream of the Kalina evaporator. For Kalina cycle -12A, this additional multi-phase expander is positioned downstream of the Kalina separator and on the weak ammonia-water solution loop for Kalina Cycle-12B. A detailed mathematical model based on the thermodynamic laws has been developed to solve and optimize the Kalina Cycles. The influence of critical decision parameters, specifically the ammonia concentration on working fluid and evaporation pressure, were investigated. The optimization was performed based on the objective to maximize the net power output from the multi-phase expander under steady-state operating conditions. When the performance of the proposed Kalina cycles was compared with the conventional Kalina Cycle-12, both of them demonstrated superior performance, i.e., net power output and peak thermal efficiency increased by a maximum value of 3.23% for the proposed Kalina Cycle-12A cycle and 3.94% for the proposed Kalina Cycle-12B cycle. In terms of second law efficiency, Kalina Cycle-12A is 3.68 percent more efficient than Kalina Cycle-12, while Kalina Cycle-12B is 4.04 percent more efficient. Furthermore, 2nd law analysis also reveals, maximum destruction of exergy occurs at the condensers of the cycles.

Small temperature difference power generation technology using a combined heat pump cycle and a Kalina cycle is predicted to reduce greenhouse gas emissions and the use of fossil fuels. It has been reported that an absorption heat pump cycle can be used as a chiller unit in the Kalina cycle to improve thermal efficiency and create an efficient cogeneration system. However, most of these studies have been performed for power generation systems of several tens of kW class or larger; there have been no studies on small temperature difference power generation systems. There is also no research on the application of absorption heat pump cycles to improve the quality of the heat sources of these systems. In this paper, we propose an integrated system that comprises an absorption heat pump cycle and Kalina cycle for small temperature difference power generation to lower the temperature requirements of the heat source. We evaluate its power generation performance and economic efficiency. The results show that our proposed integrated system can improve power generation performance by up to 81% compared to the conventional Kalina cycle, and is also more economical than the conventional Kalina cycle when applied to heat sources above 353 K.

The radial-outflow turbine has advantages due to its liquid-rich gas adaptability when applied in the Kalina ammonia-water cycle system. However, the operational conditions of the turbine often deviate from its design values due to changes of the heat source or the cooling conditions, and such deviates may deteriorate the flow behavior and degrade the turbine performance. To enhance the turbine efficiency at complex conditions for flexible running of the Kalina cycle system, a multipoint design optimization method is developed: the flexible operating has been defined by three critical, dimensionless parameters, which cover a wide range in a 3D operating space; the representative off-design points are identified to define the objective function; and adaptive optimization methods are integrated to permit optimization searching using limited CFD callings. The developed multipoint design method is adopted to improve the turbine performance under complex operating conditions. The obtained results demonstrate that the application of the developed multipoint optimization method effectively eliminates the flow separation at various operating conditions; thus, the turbine off-design performance has been comprehensively improved.

In each touristic city waste management system has to overcome the impact of visitors. Dubrovnik, famous as popular touristic destination, particularly notices tourists visiting city. Therefore potential impact of waste management in touristic cities, such as Dubrovnik, is presented. The paper includes estimation of yearly waste production by inhabitants and tourists visiting those city. Waste digestion is a method for biogas production. On the basis of the preceding estimation combined-cycle installation generating heat and electricity is proposed. The model combines Brayton cycle with low temperature Kalina model based on Rankine cycle. Literature analysis presents state of the art in this field. The simulation is prepared in Cycle-Tempo. Numerical analyses lead to technical issues, which have to be taken into consideration during waste utilization with such installation. Thus benefits and threats are discussed. The presented analysis assesses the maximal electric gain, which subsequently should consider waste preparation and purification

Combined systems for power production and thermally activated cooling have a high potential for improving the efficiency and utilisation of thermal systems. In this regard, various configurations have been proposed and are comprehensively reviewed. They are primarily based on absorption systems and the implementation of multiple levels of complexity and flexibility. The configuration of the absorption power and cooling combined cycle proposed herein has wide commercial applicability owing to its simplicity. The configuration of the components is not new. However, the utilisation of aqueous salt solutions, the comparison with ammonia chiller and with absorption power cycles, the focus on parameters that are important for real-life applications, and the comparison of the performances for constant heat input and waste heat recovery are novel. The proposed cycle is also compared with a system based on the organic Rankine cycle and vapour compression cycle. An investigation of its performance proves that the system is suitable for a given range of boundary conditions from a thermodynamic standpoint, as well as in terms of system complexity and technical feasibility. New possibilities with regard to added power production have the potential to improve the economics and promote the use of absorption chiller systems.

The Kalina cycle (KC) has been recognized as one of the most efficient conversion systems of low-grade heat sources. The Kalina flash cycle (KFC) is a recently proposed novel cycle which is equipped with an additional flash process to the KC. In this study, the exergy performance of KC and KFC driven by a low-grade heat source are investigated comparatively. The dependence of the exergy destruction at each component as well as the system’s exergy efficiency on ammonia concentration, separator pressure and, additionally, flash pressure for KFC, are systematically investigated. Results showed that KFC can be optimized with respect to flash pressure on the base of exergy efficiency, and the component where largest exergy destruction occurs varies for different separator pressure and ammonia fraction in both systems. It is also shown that the maxima of net power production and exergy efficiency in KFC with optimal flash pressure are superior to those in KC.

The article presents an assessment of the potential for using low enthalpy geothermal resources for electricity generation on the basis of the Małopolskie Voivodeship (southern Poland). Identification the locations providing the best prospects with the highest efficiency and possible gross power output. Thermodynamic calculations of power plants were based on data from several geothermal wells: the Bańska PGP-1, Bańska IG-1, Bańska PGP-3 and Chochołów PIG-1 which are working wells located in one of the best geothermal reservoirs in Poland. As the temperature of geothermal waters from the wells does not exceed 86 °C, considerations include the use of binary technologies—the Organic Rankine Cycle (ORC) and Kalina Cycle. The potential gross capacity calculated for existing geothermal wells will not exceed 900 kW for ORC and 1.6 MW for Kalina Cycle. In the case of gross electricity, the total production will not exceed 3.3 GWh/year using the ORC, and will not exceed 6.3 GWh/year for the Kalina Cycle.

The Kalina cycle (KC) has been considered one of the most efficient systems for harvesting low grade heat since its proposal and various modifications have been proposed. Recently, Kalina based power and cooling cogeneration cycles (KPCCCs) have attracted much attention and many studies have been conducted. In this paper, a cogeneration cycle of power and absorption refrigeration based on the Kalina cycle system 11 (KCS-11) is proposed. The cycle combines a KC and aqua-ammonia absorption refrigeration cycle (ABR) with once through configuration. Compared to the stand-alone KC, the proposed cycle showed significantly higher energy efficiency—as high as 60%—without the use of rectifier, superheater or subcooler. Parametric analysis showed that the ammonia fraction, separator pressure and source temperature have a significant impact on the system performance including mass flow rates, heat transfers, power generation, cooling capacity, energy efficiencies and optimum ammonia fraction for the maximum energy efficiency.

Liquid air energy storage (LAES) is a promising energy storage technology in consuming renewable energy and electricity grid management. In the baseline LAES (B-LAES), the compression heat is only utilized in heating the inlet air of turbines, and a large amount of compression heat is surplus, leading to a low round-trip efficiency (RTE). In this paper, an integrated energy system based on LAES and the Kalina cycle (KC), called KC-LAES, is proposed and analyzed. In the proposed system, the surplus compression heat is utilized to drive a KC system to generate additional electricity in the discharging process. An energetic model is developed to evaluate the performance of the KC and the KC-LAES. In the analysis of the KC subsystem, the calculation results show that the evaporating temperature has less influence on the performance of the KC-LAES system than the B-LAES system, and the optimal working fluid concentration and operating pressure are 85% and 12 MPa, respectively. For the KC-LAES, the calculation results indicate that the introduction of the KC notably improves the compression heat utilization ratio of the LAES, thereby improving the RTE. With a liquefaction pressure value of eight MPa and an expansion pressure value of four MPa, the RTE of the KC-LAES is 57.18%, while that of the B-LAES is 52.16%.

The use of a Kalina cycle (KC) with a superheater to recover waste heat from an internal combustion engine (ICE) is described in this paper. The thermodynamic and economic analyses are performed for KC. The results indicate that using KC with a superheater is a feasible method to recover waste heat from ICE. The maximum thermal efficiency of KC is 46.94% at 100% ICE percentage load. The improvement of thermal efficiency is greater than 10% at all ICE loads, and the maximum improvement of thermal efficiency is 21.6% at 100% ICE load. Both the net power output and thermal efficiency of the KC subsystem increase with ICE percentage load and ammonia mass fraction. A lower turbine inlet pressure leads to a higher net power output of KC and a greater improvement of thermal efficiency when the ammonia mass fraction of the mixture is greater than 0.34. In the paper, if the same KC, which uses the largest capital investment, is used at different ICE loads, the payback period decreases with ICE load and ammonia mass fraction. In addition, both longer annual operation times and lower interest rates lead to shorter payback periods. However, it is worth noting that the payback period will be longer than the ICE’s lifetime if the ICE load is low and the annual operation time is too short.

Ocean Thermal Energy Conversion (OTEC) using non-azeotropic mixtures such as ammonia/water as working fluid and the multistage cycle has been investigated in order to improve the thermal efficiency of the cycle because of small ocean temperature differences. The performance and effectiveness of the multistage cycle are barely understood. In addition, previous evaluation methods of heat exchange process cannot clearly indicate the influence of the thermophysical characteristics of the working fluid on the power output. Consequently, this study investigated the influence of reduction of the irreversible losses in the heat exchange process on the system performance in double-stage Rankine cycle using pure working fluid. Single Rankine, double-stage Rankine and Kalina cycles were analyzed to ascertain the system characteristics. The simple evaluation method of the temperature difference between the working fluid and the seawater is applied to this analysis. From the results of the parametric performance analysis it can be considered that double-stage Rankine cycle using pure working fluid can reduce the irreversible losses in the heat exchange process as with the Kalina cycle using an ammonia/water mixture. Considering the maximum power efficiency obtained in the study, double-stage Rankine and Kalina cycles can improve the power output by reducing the irreversible losses in the cycle.

The compressed air energy storage (CAES) system, considered as one method for peaking shaving and load-levelling of the electricity system, has excellent characteristics of energy storage and utilization. However, due to the waste heat existing in compressed air during the charge stage and exhaust gas during the discharge stage, the efficient operation of the conventional CAES system has been greatly restricted. The Kalina cycle (KC) and organic Rankine cycle (ORC) have been proven to be two worthwhile technologies to fulfill the different residual heat recovery for energy systems. To capture and reuse the waste heat from the CAES system, two systems (the CAES system combined with KC and ORC, respectively) are proposed in this paper. The sensitivity analysis shows the effect of the compression ratio and the temperature of the exhaust on the system performance: the KC-CAES system can achieve more efficient operation than the ORC-CAES system under the same temperature of exhaust gas; meanwhile, the larger compression ratio can lead to the higher efficiency for the KC-CAES system than that of ORC-CAES with the constant temperature of the exhaust gas. In addition, the evolutionary multi-objective algorithm is conducted between the thermodynamic and economic performances to find the optimal parameters of the two systems. The optimum results indicate that the solutions with an exergy efficiency of around 59.74% and 53.56% are promising for KC-CAES and ORC-CAES system practical designs, respectively.