Supercritical Carbon Dioxide Cycle Research Articles

Thermodynamic Analysis and Optimization of Binary CO2-Organic Rankine Power Cycles for Small Modular Reactors

Small nuclear power plants are a promising direction of research for the development of carbon-free energy in isolated power systems and in remote regions with undeveloped infrastructure. Improving the efficiency of power units integrated with small modular reactors will improve the prospects for the commercialization of such projects. Power cycles based on supercritical carbon dioxide are an effective solution for nuclear power plants that use reactor facilities with an initial coolant temperature above 550 °C. However, the presence of low temperature rejected heat sources in closed Bryton cycles indicates a potential for energy saving. This paper presents a comprehensive thermodynamic analysis of the integration of an additional low-temperature organic Rankine cycle for heat recovery to supercritical carbon dioxide cycles. A scheme for sequential heat recovery from several sources in S-CO2 cycles is proposed. It was found that the use of R134a improved the power of the low-temperature circuit. It was revealed that in the S-CO2 Brayton cycle with a recuperator, the ORC add-on increased the net efficiency by an average of 2.98%, and in the recompression cycle by 1.7–2.2%. With sequential heat recovery in the recuperative cycle from the intercooling of the compressor and the main cooler, the increase in efficiency from the ORC superstructure will be 1.8%.

Thermodynamic and exergy assessment of a biomass oxy-fuel combustion with supercritical carbon dioxide cycle under various recycle flue gas conditions

The ongoing development of second-generation oxy-fuel combustion system with higher oxygen concentration have presented a potential pathway for efficient biomass utilization. It also signified the meticulous role of recycled flue gas in altering the combustion behaviour in the combustor. Accordingly, investigation into different recirculation modes focusing on recycle ratio, wet/dry conditions, and excess oxygen ratio are conducted with an indirect supercritical power cycle integrated biomass oxy-fuel combustion system. Energy and exergy analyses, as well as composition of flue gas produced are presented. Energy and exergy efficiencies increased with reducing recycle ratio, with respective highest efficiency of 31.33% and 44.37% obtained at excess oxygen ratio of 1.01 and recycle ratio of 0.5 under wet condition. Investigation of CO2 and H2O concentration in produced flue gas depicted a separated stage profile under dry recycle condition, different from the slight diverging profile observed under wet condition when the recycle ratio varied. Concentration of NOx and SOx increased with decreasing recycle ratio and are generally higher under dry condition. Selective exergy analyses of the proposed power cycle presented highest exergy loss in the combustor, followed by the air separation unit, heat exchanger, CO2 compression and purification unit, and turbine generator. Based on the obtained result, wet recycle flue gas enhanced the combustion performance in the combustor but slightly impaired the convective heat transfer in the heat exchanger. The performance of proposed biomass power cycle is optimized at low recycle ratio of 0.5 under wet recycle condition.

Can injecting additional green hydrogen result in environmentally friendly solar-biomass integration? Comprehensive comparison and multi-objective optimization

The present work proposes an innovative system for decarbonizing the energy mix and accelerating the worldwide green transition process. The system is driven by a biomass digester integrated with the supercritical carbon dioxide cycle for power generation and a multi-effect desalination unit for drinkable water production. At the heart of this concept is additional hydrogen injection through a proton exchange membrane electrolyzer based on photovoltaic panels. The suggested innovative model's techno-environmental, sustainability, and economic aspects are assessed and compared with a similar system without hydrogen injection. Then, a comparative multi-criteria optimization is applied to find the most optimal conditions from various facets based on the genetic algorithm with machine learning techniques. Afterward, the system’s performance at different optimal conditions is analyzed and compared by evaluating the most significant techno-economic, environmental, and sustainability indicators. The parametric assessment comparing different models indicates that the proposed novel model, including increased hydrogen injection, surpasses the basic system in terms of performance efficiencies, emissions, and energy costs. In the first optimization scenario, the proposed method demonstrates robustness by achieving higher water production of 1456 kg/s, a lower total cost of 118 $/h, and a higher net power of 1.1 MW than the design condition. When considering the sustainability index, energy cost, and emission metric as the optimization objective, their values are altered from 0.81 to 0.85, 92.5 $/MWh to 89.7 $/MWh, and 64.2 kg/MWh to 53.6 kg/MWh. The results further show that when prioritizing the sustainability index, energy cost, and emission as objectives, all components perform better from the energy conversion quality aspect compared to the scenario where water production, total cost, and net power are the optimization objectives. Finally, it is observed that the combustion chamber and solar panels are the worst components from the irreversibility aspect because of the highest exergy destruction rate.

Supercritical carbon dioxide cycle thermodynamic and exergoeconomic improvements using a bidirectional coupling strategy

Supercritical carbon dioxide (SCO2) combined cycle power system, one of the potentially effective ways to achieve energy grade utilization of the medium and high-temperature heat sources, is vulnerable to ambient temperatures as the system performance is susceptible to the compressor inlet temperature. So far, most studies have been focused on the system performance analysis and optimization under ideal operation conditions while the mitigation of unfavorable ambient temperature is missed. In this work, a bidirectionally-coupled system is proposed to reduce the compressor inlet temperatures in the original SCO2 cycle power system so that the adverse effects of ambient temperature are alleviated. The proposal utilizes the low-grade waste heat in a SCO2 recompression reheat Brayton cycle (i.e., topping cycle) to drive an absorption refrigeration cycle (i.e., bottoming cycle) which in turn precools the compressor inlet of the topping cycle. The thermodynamic and exergoeconomic analyses have been conducted for the proposed bidirectionally-coupled combined SCO2 RRBC and ARC system, with the attention to the effects of ambient temperatures on the system performance. Our results show that the combined SCO2 RRBC and ARC system increases the energy efficiency relative to the standalone cycle power system by over 5% at the ambient temperatures of 303.15 K or above, while the exergy efficiency improves by 1.124%–3.574%. In terms of the exergoeconomic factor, the combined SCO2 RRBC and ARC system also exhibits superiority against standalone cycle power system. The current work proves that a conventional recuperated SCO2 cycle system can be improved both thermodynamically and economically by coupling it to an absorption refrigeration cycle, despite of the additional upfront costs for the components. The discovery could further promote the commercial application of the SCO2 cycle power systems in new generation plants.

Chemical looping combustion-driven cooling and power cogeneration system with LNG cold energy utilization: Exergoeconomic analysis and three-objective optimization

This study conducts thermodynamic and exergoeconomic analyses for a novel chemical looping combustion-driven cooling and power cogeneration system consisting of a supercritical carbon dioxide cycle, an air cycle, an organic Rankine cycle, and a liquid natural gas regasification process. Comprehensive parametric analyses are performed to investigate the impact of design variables on the proposed system's performance metrics, including electrical efficiency (ηel), exergy efficiency (ηex), and total product unit cost (cp,tot). A three-objective optimization is implemented to obtain the optimal system performance. The results underscore that the two reactors exhibit the highest exergy destruction of 17.29 MW, followed by the condenser's exergy destruction of 6.50 MW. The two reactors, expander, gas turbine, and condenser are the most important components within the system, and evaporator 1 and condenser need to be given more attention from exergoeconomic aspects. An optimum split ratio exists to maximize system performance by optimizing the conditions of the recycled stream into the fuel reactor. Optimization results reveal that ηel, ηex, and cp,tot cannot be simultaneously optimal and are 52.68%, 40.72%, and 27.43 $/GJ, respectively, after weighing. Moreover, the weighed performance of the proposed system outperforms those of similar systems despite employing components with lower design efficiencies.

Waste oxy-fuel combustion integrated with supercritical CO2 cycle and high-temperature electrolysis technologies for e-methanol production: A feasibility analysis

The municipal solid waste (MSW) oxy-fuel incineration power plant based on the supercritical carbon dioxide (sCO2) cycle integrated with high-temperature electrolysis technology has been developed with the aim of compensating the energy penalties of air separation unit (ASU), reducing the carbon emission and producing renewable methanol by CO2 hydrogenation process. Results shows that the suitable excess oxygen ratio, flue gas circulation ratio and methanol synthesis temperature are 1.1, 0.74 and 240 °C, respectively. The thermal efficiency of proposed system reaches 74.83%, above the that of traditional MSW incineration power plant. In addition, environmental analysis shows that the carbon retention index (CRI) is 97.76%, and the goal of near zero carbon emission can be achieved. Economic analysis demonstrates that the levelized cost of methanol (LCOM) of proposed system is 728.40 $/t, which is more than double the current market price of methanol. However, with the technological breakthrough and expansion of market scale in the further, e-methanol shows economic competitiveness when the cost of water electrolysis unit is reduced to 40 M$/250 MW and carbon emission credit is higher than 70 $/t. This work is innovative, and provides a high-efficiency and sustainable MSW disposal and energy recovering scheme for e-methanol production.

Proposal and simulation of a geothermal-driven water electrolysis unit integrated with a CO2 methanation process toward a novel sustainable framework

This paper presents a novel multigeneration structure powered by geothermal energy, featuring a geothermal power plant, water electrolyzer unit, methanation reactor, fuel and utility production unit, supercritical-carbon dioxide cycle, and both high-temperature and low-temperature organic Rankine cycles. Simulated in Aspen HYSYS software and analyzed from energy, exergy, economic, and environmental (4E) perspectives, the process, under base operating conditions, is capable of producing 20,940 kW of power, 620.70 kg/h of hydrogen, 4,913 kg/h of oxygen, 12.35 kg/s of domestic hot water, 5.293 kg/s of chilled water, and 2.659 kg/s of carbon dioxide with over 99% mole purity. Efficiency assessments reveal energy, exergy, and electrical efficiencies of 10.69%, 48.53%, and 3.73%, respectively, with a total unit product cost of $3.11/GJ and a net present value of $67.40 million. The water electrolyzer unit, with an 88.94% exergy efficiency and a 10% contribution to total system irreversibility, is identified as the most efficient subsystem. The geothermal power plant accounts for the highest system irreversibility at 61%, while the combustor in the fuel and utility production unit contributes 11,250 kW of irreversibility. Environmentally, the system operates with zero emissions and significantly reduces annual CO2 emissions compared to coal, oil, biomass, and natural gas power plants by 453.14 × 106, 576.80 × 106, 111.92 × 106, and 344.10 × 106 kg, respectively.

Control of supercritical CO2 Brayton cycle for fast and efficient load variation processes

The supercritical carbon dioxide (S-CO2) cycle is considered a promising power conversion system due to its high efficiency and flexibility. This work presents a dynamic model of a 600 MWe S-CO2 recompression Brayton cycle (RBC) and validates it at both component and system levels. To ensure the safety and stability of the S-CO2 RBC during wide-load operation, some necessary control strategies are designed, including minimum pressure and temperature control, split ratio control, turbine inlet temperature control, and anti-surge control. Moreover, an innovative valve-inventory joint control method is proposed, coupled with an improved inventory tank layout, to achieve both fast and efficient load variation processes. Compared to the control strategy before improvement, the ramp-up and ramp-down rates are significantly increased by 2.65 and 2.24 times, respectively. In addition, the values of key parameters suitable for wide-load operation of the S-CO2 RBC are determined to maximize the cycle efficiency under off-design conditions. The results show that the split ratio should be dynamically adjusted to determine the optimal value that varies with the load, which can improve the cycle efficiency by a maximum of 1.13 %. Finally, the dynamic performance of the S-CO2 RBC is studied during load ramp changes and real-time microgrid load, and the variations in heat exchange, pressure, temperature, and mass flow rate of key components are revealed. Comparative analysis with previous literature demonstrates that the proposed control method provides a wider load regulation range, an increase of 7.78 % in cycle efficiency, and a reduced maximum generation frequency deviation of 0.696 Hz. There is no overpressure or compressor surge risk, and the maximum temperature change rate is only 1.3 ℃·min−1.

Techno-Economic Analysis of the Optimum Configuration for Supercritical Carbon Dioxide Cycles in Concentrating Solar Power Systems.

There is a general agreement among researchers that supercritical carbon dioxide (sCO2) cycles will be part of the next generation of thermal power plants, especially in concentrating solar power (CSP) plants. While certain studies focus on maximizing the efficiency of these cycles in the hope of achieving a reduction in electricity costs, it is important to note that this assumption does not always hold true. This work provides a comprehensive analysis of the differences between minimizing the cost and maximizing the efficiency for the most remarkable sCO2 cycles. The analysis considers the most important physical uncertainties surrounding CSP and sCO2 cycles, such as turbine inlet temperature, ambient temperature, pressure drop and turbomachinery efficiency. Moreover, the uncertainties related to cost are also analyzed, being divided into uncertainties of sCO2 component costs and uncertainties of heating costs. The CSP system with partial cooling (sometimes with reheating and sometimes without it) is the cheapest configuration in the analyzed cases. However, the differences in cost are generally below 5% (and sometimes neglectable), while the differences in efficiency are significantly larger and below 15%. Besides the much lower efficiency of systems with simple cycle, if the heating cost is low enough, their cost could be even lower than the cost of the system with partial cooling. Systems with recompression cycles could also achieve costs below systems with partial cooling if the design's ambient temperature and the pressure drop are low.

Thermodynamic and economic analysis of a novel design for combined waste heat recovery of biogas power generation and silicon production

A novel hybrid system based on a combination of a gas turbine cycle, a supercritical carbon dioxide cycle, and an organic Rankine cycle is devised for power generation. Based on the joint layout proposed in this study, the collaborative and efficient utilization of biogas from anaerobic digestion and flue gas from industrial silicon production can be realized. The clean biogas harvested from anaerobic digestion is exploited by a gas turbine, and the resulting hot exhaust gas is then combined with the flue gas from industrial silicon production to power the supercritical carbon dioxide cycle. Addition, the organic Rankine cycle is added as the bottom cycle in the supercritical carbon dioxide cycle to further improve the waste heat utilization efficiency. Energy, exergy, and economic analysis are performed to assess the system's performance and feasibility, the energy and exergy efficiencies are calculated as 43.61 % and 51.07 %, only 4.09 years are needed to recoup the initial investment of the design, and the net present value is as high as 136,864.14 k$.

Optimization of a wavy-channel compact solar receiver with supercritical carbon dioxide

The compact solar receiver stands out as a promising solar absorber for the direct supercritical carbon dioxide cycle, and the wavy channel exhibits notable comprehensive performance owing to its excellent heat transfer capabilities and relatively low flow resistance. However, there exists considerable room for improvement in performance through the optimization of geometric parameters in wavy channels. In this paper, the amplitude and the period of the wavy channel are optimized by a coupled response surface method with multi-objective genetic algorithm, with objectives of maximizing the heat transfer coefficient and minimizing the friction factor. Results indicated that smaller period or larger amplitude enhances heat transfer but also increases flow resistance. Through the non-dominated sorting genetic algorithm and k-means clustering method, five representative optimal solutions were identified. The optimal result, characterized by a period of 15.07 mm and an amplitude of 1.73 mm, was selected based on the highest comprehensive heat transfer factor under identical pump power, reaching 1.213. This solution demonstrated high comprehensive performance across a wide range of working conditions. The optimization results are not only valuable for the design of compact solar receivers but also hold significant potential for application in other compact heat exchangers, such as printed circuit heat exchangers.

Optimizing Energy Recovery from Marine Diesel Engines: A Thermodynamic Investigation of Supercritical Carbon Dioxide Cycles

Optimizing Energy Recovery from Marine Diesel Engines: A Thermodynamic Investigation of Supercritical Carbon Dioxide Cycles

Thermodynamic Modelling, Technical and Operational Issues of Supercritical Carbon Dioxide Power Generation Cycles for Industrial Applications: A Literature Review

Future electricity production systems will be able to harness the power of supercritical carbon dioxide (S-CO<sub>2</sub>) as it moves through thermal cycles. It serves the same goal as sources of energy such as fossil fuels, nuclear power, solar power, and the recovery of waste heat (or surplus heat from industrial processes). When the heat source temperature is between 350°C and 800°C, CO<sub>2</sub> as a working fluid exhibits excellent thermal efficiency. Its novel technological benefits over conventional steam Rankine cycles, such as the use of small turbo gear and compact heat exchangers, have captured the attention of scientists. It has excellent operational flexibility and may induce significantly cheaper energy costs. Aligned with these goals, this paper presents a panoramic work, exploring the current state of the art of S-CO<sub>2</sub> power generation, with a particular emphasis on the technical and operational perplexities. After providing a comprehensive overview of the thermodynamic principles that underpin this study, the foundation is established for an engaging discourse on the continuous research and development of supercritical carbon dioxide (S-CO<sub>2</sub>) cycles in power generation. Upon delving into the thermodynamic facets of CO<sub>2</sub> that propel this investigation, the spotlight is cast upon dissecting the existing state of research and development of S-CO<sub>2</sub> cycles in power generation before transitioning into encapsulating the principal domains of application and noteworthy thermodynamic modelling inquiries of S-CO<sub>2</sub> cycles. The present advancements and hurdles within the primary application areas are succinctly summarized, while future research trends are identified.

Thermodynamic and exergoeconomic evaluation of coal and biomass co-gasification as solid oxide fuel cell feed coupled with supercritical carbon dioxide and organic Rankine cycle

Coal-biomass cogeneration technology can not only diversify energy supply, but improve the combustion characteristics of coal and enhance system performance. This work developed a power generation system for co-gasification of coal and biomass to supply solid oxide fuel cell, and coupled with a dual system of supercritical carbon dioxide cycle and organic Rankine cycle to achieve energy cascade utilization. A comprehensive thermodynamic analysis was conducted to evaluate and optimize this system more intuitively. Constrained optimization algorithms elucidated the optimal parameters, identifying an oxygen-to-fuel mass ratio of 0.48 and a steam-to-fuel ratio of 0.18. These conditions led to a higher gasification temperature and optimal syngas yield. And sensitivity analysis on three biomass types confirms that dry and carbon-rich biomass is ideal for system doping. With a 20% doping amount, the system achieves 59.18% maximum thermal efficiency and 2.43 kg/MWh net carbon emission, outperforming the single fuel cell system by 11.14% and 4.79% respectively. The discount rate has the greatest impact on system costs in economic analysis, with a 30% fluctuation causing system costs to vary by about 14.31%. In addition, the exergy and exergoeconomic analyses identify cost formation, propose efficiency measures, and enhance cost-effectiveness.

An innovative S–CO2 recompression Brayton system and its thermodynamic, exergoeconomic and multi-objective analyses for a nuclear spacecraft

An innovative layout of a recompression supercritical carbon dioxide (S–CO2) cycle for nuclear spacecraft was proposed in this work. Thermodynamic and exergoeconomic analysis of the innovative cycle have been performed to study the effect of essential operating parameters on the split ratio, maximum operating pressure ratio, minimum operating temperature, maximum operating temperature, and compressor C4 inlet pressure based on the first and second laws of exergoeconomics and efficiency. Finally, the innovative power cycle is optimized with high efficiencies, low cost and lightweight. The results show that the optimization progress is based on the thermodynamic and exergoeconomics method; the minimum operating temperature can significantly improve efficiencies and reduce circular investment cost; then after the multi-objective optimization progress, the thermal efficiency (ηth), exergy efficiency (ηex) and mass of Brayton turbomachinery unit (MBTU) improved by 2.71 %, 3.69 %, and 2.8 %; total capital cost rate (total) and levelized cost of electricity (LCOE) reduced by 0.88 % and 4.55 %, respectively.

Thermodynamic evaluation of a state-of-art poly-generation system fueled by natural gas and biomass for cooling, power, and hot water generation

The principal objective of this study was to conduct a thorough examination of the thermodynamic aspects of an innovative combined poly-generation facility, encompassing cooling load, hot water, and power generation cycles, powered by a combination of natural gas and biomass. A distinctive feature was the incorporation of syngas into natural gas to enhance overall plant performance. The plant design comprised three key subsystems: a gasification and combustion chamber, a double-effect absorption chiller, and a supercritical carbon dioxide cycle. Energy and exergy analyses were employed to systematically evaluate the thermodynamic behavior of the plant. The outcomes revealed that the exergy and energy efficiencies, along with the net power output, were determined to be approximately 35 %, 78 %, and 7422 kW, respectively. Additionally, the produced hot water and the coefficient of performance (COP) of the absorption chiller were estimated at around 14.71 kg/s and 1.209. Notably, the gasifier and combustion chamber emerged as the least efficient components of the system, primarily due to their elevated rates of exergy destruction. Furthermore, comprehensive parametric investigations were conducted to elucidate the influence of key variables on plant performance. The analysis indicated that variations in gasification temperature positively impacted the thermodynamic performance of the plant. Moreover, an increase in combustion pressure led to a notable enhancement in the net power output of the facility.

New procedure for an optimal design of an integrated solar tower power plant with supercritical carbon dioxide and organic Rankine cycle and MED-RO desalination based on 6E analysis

In this paper, an innovative structure for the production of electricity and freshwater in Kangan Port, located in southern Iran and close to the Persian Gulf, is developed and analyzed. Heliostat collectors are employed in this process to provide the necessary thermal energy in the supercritical carbon dioxide (S-CO2) cycle, the organic Rankine cycle (ORC) and desalination unit. Additionally, implementing the current multi-effect desalination (MED) processes unit with the reverse osmosis (RO) system as well as employing the sun's thermal collector field to enhance the system's achievement and propose the best plan for the unit that operates has been looked into. ASPEN HYSYS software, Meteonorm package, and MATLAB programming are used to simulate the proposed system. Concurrently, this integrated power plant exhibits the capacity to simultaneously generate 117 kg/s of freshwater and yield 25.14 MW of power. The integrated structure has a thermal efficiency of 36% and a overall exergy efficiency of 31.99. Exergy study reveals that heat exchanger 8 and turbine 3 experience the most exergy destruction. To recover lost heat and produce additional electricity, organic Rankine cycle are used. Investigations are done on seven organic fluids in the ORC unit. The system is better understood from several views with the assistance of energy, exergy, exergoeconomic, exergoenvironmental, emergoeconomic, and emergoenvironmental (6E) analyses. In this regard, m-file codes in MATLAB programming for 6E analyses are developed. The generated code's thermodynamic simulation is accurately compared to ASPEN HYSYS software. Additionally, sensitivity analysis depending on the primary parameters is carried out. For a thorough study of each component, advanced exergy-based analysis linked to avoidable/endogenous and unavoidable/exogenous segments is carried out. The objective functions and chosen variables are optimized using a genetic algorithm. The best organic fluid in terms of thermodynamics is n-hexane and the ideal organic fluid from an economic and environmental standpoint stands R-113. The overall system's cost rate and environmental impact are obtained at 0.1679 $/s and 0.000545 pts/s, respectively.

Comparative analysis of supercritical CO2–ORC combined cycle for gas turbine waste heat recovery based on multi-objective optimization

To efficiently recover the waste heat of the gas turbine, this study introduces six innovative types of compound combined cycles, and proposes a multidimensional optimization method for the optimal cycle. In the combined cycle, the supercritical carbon dioxide cycle is used in the top cycle and the organic Rankine cycle is used in the bottom cycle. The working medium used in the organic Rankine cycle is the innovative mixture cyclopentane/R365mfc. Firstly, a parametric study is carried out for the proposed combined cycle to investigate the effects of system operating parameters on exergy efficiency, area per unit power output (APR) of the heat exchanger, and the levelized energy cost (LEC). The results show that the optimal values of objective function correspond to different systematic operating parameters. Secondly, the multi-objective optimization based on the genetic algorithm is used to obtain the optimal systematic parameters, and the six proposed composite combined cycles are optimized respectively. The comparison results show that the composite supercritical carbon dioxide regenerative cycle-organic Rankine simple cycle has the optimal performance parameters, and its exergy efficiency, APR and LEC are 55.68 %, 0.115 m2/kW and 4.23 cent/(kW·h), respectively. The layout of the composite cycle is that the supercritical carbon dioxide regenerative cycle and the organic Rankine simple cycle are used to recover the high temperature and low temperature of the gas turbine exhaust gas, while the organic Rankine simple cycle recovers the cooling heat of the supercritical carbon dioxide regenerative cycle. Finally, the superiority relative of the proposed combined system to the other cycles is also verified. This study has determined that the proposed combined system is appropriate for the waste heat recovery of gas turbines, with the advantages of deep utilization of waste heat, high efficiency, high compactness, and low cost.

Development and assessment of a novel integrated system powered by parabolic trough collectors for combined power, heating and freshwater production

Abstract Hybrid solar-based integrated systems represent a viable solution for countries with abundant solar radiation, as they provide energy needs in an environmentally friendly way, offering a sustainable and economically advantageous energy solution that utilizes a free source of energy. Therefore, this research offers a thermodynamic evaluation of a novel integrated system driven by solar energy that aims to produce power, heating and freshwater. The integrated system consists of a parabolic trough collector that uses CO2 as its working fluid and implements the supercritical carbon dioxide cycle to generate power and heating. The integrated system also includes an adsorption desalination system with heat recovery between the condenser and evaporator, which employs a cutting-edge material called an aluminium fumarate metal–organic framework to produce fresh water. For the modelling of a novel system, an engineering equation solver, which is considered a reliable tool for thermodynamic investigations, is employed. The effectiveness of an integrated system is evaluated using a mathematical model and different varying parameters are examined to ascertain their influence on thermal and exergy efficiency, specific daily water production and gained output ratio. The results revealed that the parabolic trough collector achieved a thermal efficiency of 67.2% and an exergy efficiency of 41.2% under certain conditions. Additionally, the thermal efficiencies for electrical and heating were obtained 24.68% and 9.85%, respectively. Finally, the specific daily water production was calculated, showing promising results and an increase from 7.1 to 12.5 m3/ton/day, while the gain output ratio increased from 0.395 to 0.62 when the temperature of hot water increased from 65°C to 85°C, under the selected conditions.

Design and analysis of an innovative biomass-powered cogeneration system based on organic flash and supercritical carbon dioxide cycles

Technological advancements play a significant role in increasing energy demand. As societies progress, new technologies emerge, and they often require additional energy resources to operate. Therefore, it is important to design an efficient power system that can achieve higher performance. Additionally, considering the environmental aspect of the designed system is another crucial criterion for power system design. The current investigation proposes a renewable-based co-generation system for the production of power and heating load. The proposed system consists of several subsystems, including a municipal solid waste-driven gas turbine cycle, a supercritical CO2 cycle, and a high-temperature organic flash cycle. The system's performance is analyzed using energy, exergy, economic, and environmental approaches. Double-objective and triple-objective optimizations are applied to determine the optimum state of the system. The results indicate that the system can produce a net power of 8.21 MW and a heating load of 5.81 MW. This translates to energy and exergy efficiencies of 75.8 % and 41.21 % respectively, with a levelized CO2 emission of 0.518 t/kWh at the base-case. Furthermore, the system's payback period is estimated to be approximately 1.97 years, resulting in a net profit of 10.7 M$. In the parametric study, it was found that the gas turbine's inlet temperature has a significant impact on the system's performance indexes. Ultimately, the system achieves an exergy efficiency of 43.18 % and a levelized CO2 emission of 0.457 t/kWh at the optimum state. In conclusion, the proposed renewable-based co-generation system offers a promising solution for achieving higher performance, environmental sustainability, and economic viability in the design of efficient power systems. In conclusion, the proposed renewable-based co-generation system offers a promising solution for achieving higher performance, environmental sustainability, and economic viability in the design of efficient power systems.