Multigeneration Plant Research Articles

Development and modeling of power, hydrogen and freshwater production based on a novel double-flash geothermal power plant

In this article, a novel geothermal energy-assisted multigeneration plant is proposed and analyzed from the thermodynamic, economic, and environmental perspectives. In the design of the geothermal power system, a transcritical Rankine cycle, which employs CO2 as the working fluid (tCO2-RC), a Kalina cycle (KC), a hydrogen generation sub-plant, and a desalination unit are considered. The reverse osmosis (RO) desalination process is used for freshwater production, while the proton exchanger membrane (PEM) electrolyzer is utilized for hydrogen generation. In addition, parametric analyses are conducted to ascertain the impacts of the temperature of the geothermal source, mass flow rate, and flash chamber pressure on system performance. According to the results, the plant's overall energetic and exergetic efficiencies are determined to be 8.6 % and 34.9 %, respectively where the net power production is calculated as 3317.94 kW, and the system's total irreversibility is found to be 5852.88 kW. Furthermore, the hourly H2, O2, and freshwater generation amounts are 8.5 kg, 49.1 kg, and 9.3 m3, respectively. Finally, the levelized energy cost (LEC) and sustainability index of the system are found to be 0.128 USD/kWh and 0.215.

Optimization and exergoeconomic analyses of water-energy-carbon nexus in steel production: Integrating solar-biogas energy, wastewater treatment, and carbon capture

The steel industry is one of the hard-to-abate sectors for decarbonization, and direct electrification is not possible or economically infeasible. This study investigates the application of the Water-Energy-Carbon nexus in the steel industry through a multi-generation plant, addressing the industry's demands for water, energy, and alternative fuel. The proposed multi-generation plant consists of parabolic trough solar collectors, an organic Rankine cycle, urban wastewater treatment, carbon capture, anaerobic digestion combined with heat and power, a proton exchange membrane electrolyzer, and a steelmaking plant. Thermodynamic and exergoeconomic analyses are conducted to investigate the system's efficiency and economic performance. A sensitivity analysis is conducted to identify the optimal links between nexus resources, followed by a multi-dimensional evaluation and multi-objective optimization. The results showed that under base conditions, the plant can annually produce 900 ktons of steel, 105 GWh of net power, 430.1 tons of water, and 517 tons of hydrogen, while preventing 34.7 ktons of CO2 emissions. The exergy efficiency and unit exergy cost of the products are 46.1% and 57.8 $/GJ, respectively. Under optimized conditions, the plant achieves a maximum net annual power output of 160 GWh, an exergy efficiency of 46.9%, and a minimum unit exergy cost of 51.4 $/GJ.

Energy and environmental assessment of a novel multigeneration plant powered by infectious medical waste

This study highlights the energy and environmental impacts of a multigeneration system for infectious medical waste -to-energy (IMWtE). Thermal performance and life cycle assessment (LCA) are investigated via the energy conservation, ReCiPe method, SimaPro database, and situation of environmental issues in Thailand and worldwide. A lifespan of 20 y is considered in this study. The energy results show that the multigeneration system can produce a net power of 15.80 kWe from an organic Rankine cycle (ORC), 4.62 kW of cooling power from an absorption chiller, and 13.21 kW of heating power from a drying room. An overall system efficiency of 13.40% is directly driven from an infectious medical waste (IMW) of 81.98 kg/s. According to the LCA results, the construction phase has the highest emissions (81%), followed by the operation phase (6%) and the landfill (1%). The recycling process reduces the environmental impact by 12%. The total lifetime midpoint impact is 3.88E-01 kg emission-eq/kWh. The endpoint includes 4.33E-07 DALY/kWh of human health, 1.50E-06 Species·y/kWh of ecosystem, and 3.81E-03 USD/kWh of resources. The LCA single score is approximately 6.08E+02 Pt/lifespan or 5.63E-04 Pt/kWh.

Process arrangement and multi-aspect study of a novel environmentally-friendly multigeneration plant relying on a geothermal-based plant combined with the goswami cycle booted by kalina and desalination cycles

In this study, a novel trigeneration system for cooling, heating, freshwater, and electricity generation, driven by geothermal energy is evaluated from thermodynamics, thermoeconomic, and environmental perspectives. To gain a better understanding of the system's performance, energy and exergy analyses are conducted, and the outcomes are compared with other studies. The proposed structure includes a single-flash geothermal plant, a water desalination unit, the Goswami power and cooling cycle, and the Kalina power cycle. This analysis is conducted using Aspen HYSYS software, and the results demonstrated that the single-flash geothermal plant has the highest irreversibility (48 %), and the major sources of irreversibility among all equipment are the heat exchangers, contributing to 68 % of the total exergy destruction rate. Additionally, it is observed from the thermodynamic analysis results that the energy and exergy efficiencies and the total unit cost of products of the proposed process are 32.28 %, 51.71 %, and 5.66 $/GJ, respectively. According to the results, the production rate of the products is cooling (24.8 m3/h), steam (27.44 m3/h), domestic hot water (209.7 m3/h), fresh water (45.02 m3/h), and electric power (16260 kW). The environmental analysis shows that the new process has zero CO2 emission and can save an annual consumption of petroleum equal to 4325160 L, and when compared to the power plants with natural gas and oil as fuel, CO2 emissions are prevented equal to 5691000 kg/year and 13804740 kg/year, respectively.

Advances in zero liquid discharge multigeneration plants: A novel approach for integrated power generation, supercritical desalination, and salt production

In light of the escalating worldwide demand for energy and water resources, the imperative for developing sustainable multigeneration systems has gained prominence in recent research and development. This study aims to investigate the feasibility and performance of a novel multigeneration plant operating at supercritical conditions to simultaneously generate freshwater, power, and dry salt as a by-product while eliminating liquid discharge. This approach offers a promising solution to address the interconnected challenges of energy and water sustainability. The theory contends that combining supercritical desalination with power generation increases energy efficiency and water production rates, surpassing conventional systems. Therefore, a model is developed employing a supercritical once-through boiler capable of supplying the necessary heat duty required for steam generation from the integrated desalination plant, producing power. Additionally, multiple heat exchangers and flash separators are implemented, enhancing freshwater productivity and obtaining dry salt, eliminating the need for brine waste disposal. A thorough sensitivity analysis is conducted utilizing a robust model developed on Aspen HYSYS to ascertain the optimal operational parameters of the proposed plant. The findings of this study underscore the potential of concurrent production of 1.65 million m3/year of freshwater, 302.5 GWh of electricity, and 64,845 ton/year of dry salt for 0.38 $/m3, 0.07 $/kWh, and 0.02 $/kg, respectively. In conclusion, this research highlights the prospects of revolutionary progress in multigeneration systems for sustainable development.

An innovative geothermal based multigeneration plant: Thermodynamic and economic assessment for sustainable outputs with compressed hydrogen

In the net-zero emissions strategy adopted to struggle global warming and environmental difficulties, the effective utilization of clean energy sources is important. In this framework, geothermal sources are an important renewable energy sources and offer many advantages. In the developed new research, a geothermal energy-supported combined configuration is considered and proposed for sustainable hydrogen, power, freshwater, hot water, and drying. In this system, an exhaustive thermodynamic examination, -energy, exergy efficiency, and exergy destruction-, as well as an economic analysis are carried out. This newly designed configuration comprises a flash-geothermal circuit, a transcritical CO2 fluid Rankine plant (tRC), a dryer, a multi-effect desalination (MED) component, and a Proton exchange membrane (PEME) and hydrogen storage units. In light of the analysis outcomes, the power generation load of the system is 1587 kW and the hydrogen quantity is calculated 0.00223 kg/s. In addition, the thermodynamic performance indicators, which are energetic and energetic performance of the tRC are determined as 10.91% and 41.68%. Moreover, the energetic efficiency of the modeled configuration is determined to be 23.18%, whereas the exergetic performance indicator is found to be 28.57%. Regarding the economic cost evaluations, the total cost of this model is calculated as 171.5 $/h.

Thermodynamic and environmental performance of a Kalina-based multigeneration cycle with biomass ancillary firing for power, water and hydrogen production

The performance of a Kalina-based multigeneration cycle for power, water, and hydrogen production is investigated from thermo-environmental, sustainability, and thermo-economic perspectives. The plant comprises a gas turbine (GT), Kalina cycle (KC), and vapor absorption system (VAS) as the bottoming cycle and an integrated domestic water heater and proton-electron membrane (PEM) electrolyzer for hydrogen production. The system's models were simulated with Engineering Equation Solver (EES) codes. The results indicate a net energy efficiency of 53.48% and exergy efficiencies of 50.05 %, with an additional 30,178 kW of products from the bottoming cycles. The GT contributed approximately 85.81 % of the overall exergy destruction. The system's exergo-thermal index (ETI) stood at 1.713, with the GT only having an ETI of 2.106. Similarly, the exergetic sustainability index (ESI) of the multigeneration plant was not greater than 2.04. The exergoeconomic analysis shows a low average energy cost from the GT, estimated at 0.836 $/GJ, compared to the Kalina subsystem, which stood at 6.53 $/GJ. The thermodynamic and cost evaluation of the system demonstrates substantial benefits from the plant, which kept the hydrogen production rate at 0.1524 kg/hr.

A fuel gas waste heat recovery-based multigeneration plant integrated with a LNG cold energy process, a water desalination unit, and a CO2 separation process

Development of the multigeneration plants based on the simultaneous production of water and energy can solve many of the current problems of these two major fields. In addition, the integration of fossil power plants with waste heat recovery processes in order to prevent the release of pollutants in the environment can simultaneously cover the environmental and thermodynamic improvements. Besides, the addition of a carbon dioxide (CO2) capturing cycles with such plants is a key issue towards a sustainable environment. Accordingly, a novel waste heat recovery-based multigeneration plant integrated with a carbon dioxide separation/liquefaction cycle is proposed and investigated under multi-variable assessments (energy/exergy, financial, and environmental). The offered multigeneration system is able to generate various beneficial outputs (electricity, liquefied CO2 (L-CO2), natural gas (NG), and freshwater). In the offered system, the liquified natural gas (LNG) cold energy is used to carry out condensation processes, which is a relatively new idea. Based on the results, the outputs rates of net power, NG, L-CO2, and water were determined to be approximately 42.72 MW and 18.01E+03, 612 and 3.56E+03 kmol/h, respectively. Moreover, the multigeneration plant was efficient about 32.08% and 87.72%, respectively, in terms of energy and exergy. Economic estimates indicated that the unit product costs of electricity and liquefied carbon dioxide production, respectively, were around 0.0466 USD per kWh and 0.0728 USD per kg-CO2. Finally, the total released CO2 was about 0.034 kg per kWh. According to a comprehensive comparison, the offered multigeneration plant can provide superior environmental, thermodynamic, and economic performances compared to similar plants. Moreover, there was no need to purchase electricity from the grid.

Comprehensive analysis and optimization of a low-carbon multi-generation system driven by municipal solid waste and solar thermal energy integrated with a microbial fuel cell

Abstract In this article, a novel multi-generation plant is addressed and assessed from the energy, exergy, exergoenvironmental and exergoeconomic points of view. The multi-generation plant is composed of two main units: one unit for energy production and another unit for carbon capture and methanol synthesis. Biomass fuel, solar energy and seawater are the main nutrients in the plant. Steam, Brayton, organic Rankine and Kalina cycles have been employed to generate electricity. A linear Fresnel collector-driven solar farm is considered as an auxiliary heat source. In addition, an integrated desalination unit based on a multi-effect desalination unit, a microbial fuel cell and a reverse osmosis unit has been installed in the multi-generation plant. The proposed structure for the offered multi-generation plant is designed under a new configuration and layout that had not been reported in the publications. From the outcomes, the multi-generation plant can produce 69.6 MW of net electricity, 0.53 kg/s of methanol, 0.81 kg/s of oxygen gas, 73.8 kg/s of fresh water and ~0.015 kg/s of hydrogen gas. Under such performance, the offered multi-generation plant can be 51.72 and 27.5% efficient from the points of view of energy and exergy, respectively. Further, the total cost rate and environmental impact of the plant are ~3378 US$/h and 294.1 mPts/s, respectively. A comparative analysis is developed to exhibit the superiority of the planned multi-generation plant. A five-objective optimization is also developed to achieve the optimum design data and outcomes of the plant.

Multi-aspect analysis and optimization of biomass-fueled multi-generation plant

Biomass fuels are an interesting renewable energy, which represents a higher performance, especially their integrated mode with the solid oxide fuel cell. This integration provides a higher thermodynamic performance along with a lower environmental impact. Hence, the current paper proposes an innovative multi-generation consisting of biomass-fueled solid oxide fuel cell combined with a gas turbine cycle. This integration's wasted heat is harnessed via a steam Rankine cycle, a double-effect refrigeration cycle, and a proton exchange membrane electrolyzer. Furthermore, the heat loss of the steam Rankine cycle is utilized to drive an organic Rankine cycle. The energy, exergy, economic, and environmental approaches are implemented to attain the designed scheme's performance. Five multi-objective optimization scenarios are applied to assess a proper optimal operating mode. The results showed that the gasifier is the main source of exergy destruction, with a value of 597.4 kW. Also, the increment of cell number in the fuel cell and gasification temperature reduces both thermodynamic and economic performances. At the optimal state, the deigned configuration’s exergy efficiency and payback period are attained about 60.03% and 1.45 years.

Development and performance analysis of a solar-powered multigeneration plant with a reheat CO2 cycle for sustainable outputs

Development and performance analysis of a solar-powered multigeneration plant with a reheat CO2 cycle for sustainable outputs

Design and analysis of a novel multigeneration plant utilizing geothermal energy

Design and analysis of a novel multigeneration plant utilizing geothermal energy

Thermodynamic and exergoenvironmental assessment of an innovative geothermal energy assisted multigeneration plant combined with recompression supercritical CO2 Brayton cycle for the production of cleaner products

The current study examines a novel multigeneration plant that uses geothermal energy to produce clean and sustainable products. The process includes a re-compression supercritical Brayton power plant (re-sBC), an ejector cooling unit (EJCS), a humidifier dehumidifier desalination (HDH) unit, a Proton-Exchange Membrane (PEM) process, and a hot water preparation unit. The designed plant is able to generate hot water, cooling, power, hydrogen, and freshwater using the geothermal source. In the current paper, the thermodynamic analysis, CO2 emission assessment, and exergoenvironmental index evaluation are executed to determine the system efficiency and the association between the system and the environment. A thorough parametric examination is fulfilled, to show how the system indicators impact efficiency and generated products. According to analysis data, the proposed multigeneration plant is able to generate 1278 kW of heating load, 229.6 kW of refrigeration capacity, and 109.5 kW of net power rate. Additionally, the capacity of the freshwater is 0.1188 kgs−1 and the hydrogen is 0.001317 kgs−1. This developed system emits a total of 117 tonnes of CO2 emissions per year for these useful outputs. In conclusion, the energetic and exergetic performance of the suggested MG plant are 14.09 % and 23.35 %, respectively.

An innovative study on a geothermal based multigeneration plant with transcritical CO2 cycle: Thermodynamic evaluation and multi-objective optimization

Renewable energy-sourced integrated plants are among the novel and interesting technologies for production of the clean and effective beneficial multiple commodities. Also, these technologies are one of the main motivations for overcoming environmental troubles. The newly designed geothermal-based multigeneration plant deals with clean and sustainable power, hydrogen, cooling, and heating generation and then comprehensive thermodynamic and economic analyses. This system is driven by a geothermal source that includes a transcritical CO2 based Rankine cycle, an ejector cooling cycle, a hydrogen generation and compression unit, and a domestic hot water preparation unit. Here, a comprehensive mathematical modeling is discussed that are energy and exergy efficiency methods along with economic cost evaluation. Furthermore, to define the optimal working conditions, a multiobjective optimization method is fulfilled based on the relationship between the developed multigeneration system's cost and exergy efficiency. Additionally, a comprehensive parametric assessment is implemented to describe how effects of various indicators on the developed model’s efficiency. In outlook of these outcomes, it is crystal clear that the quantity of clean power and hydrogen generation rate is 1283 kW and 0.009374 kgs−1, respectively. The energy and exergy efficiencies of the developed MG cycle are figured as 27.60% and 22.56%, at 152 ℃ geothermal source temperature. the optimal plant total cost rate is computed as 80.48 $h−1. Finally, it is concluded that this proposed system's performance and cost rates are compatible and applicable.

Development of a new multi-generation system integrated with the S-Graz and Cu-Cle cycles for ammonia, hydrogen and power generation

A new multi-generation plant incorporated with the ammonia synthesis reactor, a Cu-Cl cycle, and a S-Graz cycle plus a gas turbine cycle for electricity, hydrogen as well as ammonia production recommended and dissected from exergy, energy, exergoeconomic, exego-environmental, and environmental (5E) aspects, in this research. Furthermore, to investigate the effect of input variables on the plant function criteria, exhaustive sensitivity evaluations were carried out and disputed in detail. The exergy and energy yields, the products ‘sum unit cost, the cost rate of environmental penalty as well as the emission rate of the offered poly-generation plant have been 41.16%, 45.57%, 369.6 $/GJ, and 0.0001319, respectively. Besides, the plant provided the net power output, hydrogen, and, ammonia of 151488 kW, 0.2199 kg/s, and 1.884 kg/s, sequentially. Also, the whole exergy destruction rate of the plant was computed at about 128.289 MW. Finally, the sensitivity investigations resulted that increasing the hydrogen molar flow rate and high-temperature turbine (HTT) inlet temperature had a positive effect on the techno-eco-environmental performances of the system.

Performance Evaluation of a Novel Multigeneration Plant of Cooling, Power, and Seawater Desalination Using Supercritical CO2 Partial Cooling, ME-TVC Desalination, and Absorption Refrigeration Cycles

Multigeneration systems have gained popularity and approval from scientific minds due to the enhancements these systems bring to total energy utilization efficiency. The use of waste heat from different thermodynamic cycles ensures deceleration of environment pollution. In this paper, a newly conceptualized poly-generation system combining power, cooling and desalination is proposed. Despite the high efficiency generated by the next generation supercritical CO2 (sCO2) Brayton cycles, the pre-coolers (cooling components) of the power block experience a substantial amount of low-grade energy loss. Utilizing this energy loss to increase thermal efficiency further has been the driving force behind this research. The proposed system has three subsystems which are sCO2 Partial cooling cycle with reheat for power generation, followed by a ME-TVC (multi-effect desalination-thermal vapor compression) cycle for producing fresh water and finally an absorption refrigeration cycle (ARC) to provide refrigeration effect. The waste heat from precoolers of sCO2 partial cooling cycle are being utilized by the desalination plant and refrigeration cycle for enhanced system performance. A comprehensive mathematical model is developed and a parametric assessment is performed. The parametric investigation focuses on the primary performance parameters, namely net power output, freshwater yield, energy utilization efficiency, coefficient of performance, and gain output ratio, to assess the multi-generation system's performance across various operational scenarios. The variables that are optimized are turbine inlet temperature of the sCO2 cycle, temperature difference of the generator and the evaporating temperature of the absorption cycle, the number and temperature of the effects of the desalination system. The results show that the greatest energy efficiency of the developed system is up to 70%. The 1st law energy efficiency is termed as Energy Utilization Factor (EUF) in the present work. This term adheres to the logic of the first law of thermodynamics by relating the total energy outputs to the system (work plus refrigeration capacity and heat supplied to the desalination plant) to the total energy input. Using the default parameters, the COP of the ARC is 0.667 and the EUF of the combined system is 59%. Both of these values are higher when compared to previous combined cycles found in literature.

Design and optimization of a multi-level wasted heat recovery system for a natural gas-based gas turbine cycle; comprehensive exergy and economic analyses

The increasing demand for power and the imperative of harnessing wasted heat to optimize power systems have motivated this current study. The main goal is conceptualizing an innovative multi-generation plant fueled by natural gas, which ingeniously integrates four distinct cycles: steam Rankine, absorption power, ejector refrigeration, and proton exchange membrane electrolyzer. This integration is synergistically coupled with a gas turbine to elevate overall system performance significantly. The investigation extends to the thorough examination, including the system's energy, exergy, and economic attributes, facilitating an all-encompassing assessment of the newly conceived plant's efficiency. Through a meticulous parametric inquiry, the study scrutinizes the influence of various parameters on the operational prowess of the system. Moreover, the quest for optimum performance unfolds through a multi-objective optimization process conducted across three distinct scenarios. Regarding the outcomes, at the base operating conditions, the novel system exhibits the capacity to yield 3,896.6 kW of net power, additionally generating a cooling load of 77.7 kW and producing 0.22 kg/h of hydrogen. Notably, it attains an exergy efficiency of 47.1 %, with the combined unit cost of products and a commendable payback period measuring at 9.16 $/GJ and 1.4 years, respectively, under baseline conditions. The preeminent role in exergy destruction is attributed to the gas turbine cycle, accounting for 88.59 % of the total, while the highest share of the total investment cost is allocated to the turbines. The pinnacle of optimal performance is realized in a state wherein the system achieves its zenith in terms of efficiency and output, reflecting the culmination of meticulous design and analysis.

Development and assessment of a novel multigeneration plant combined with a supercritical CO2 cycle for multiple products

Multigenerational energy conversion plants are one of the most promising solutions for tackling environmental challenges and making efficient use of energy sources. In this regard, a newly designed multigeneration plant integrated with a methane-based Brayton cycle, a steam Rankine cycle, a supercritical CO2-based Brayton cycle, a multi-effect desalination process, a PEM unit, a domestic water heater process, and two thermoelectric generators is integrated, proposed and analyzed. The thermodynamic and environmental assessments of the developed paper are conducted and examined with energy and exergy efficiencies as well as CO2 emission rate. Similarly, a parametric study is executed and reported, by the way, to define the impact of the various significant factors on the developed plant's efficiency. In the end, the CO2 emission rate is determined and compared according to different energy conversion plants. In light of the analysis results, the net power, hydrogen, and freshwater production capacities of the reference study are calculated to be 1336 kW, 0.002004 kgs−1, and 0.954 kgs−1, respectively. Additionally, it is found that the developed study's energetic and exergetic performances are 55.76% and 52.17%. According to emission analysis results, the multigeneration system emits 272.2 kg/MWh less CO2 emissions than the single energy conversion system.

Development and analysis of geothermal energy-based low-grade heat utilization in an integrated form for multigeneration with hydrogen

Multigeneration systems offer more effective solutions compared to other conventional energy production systems. Also, geothermal energy plays a crucial role in changing fossil-based energy infrastructure to a renewable source. In this piece of scientific work, a novel geothermal energy-based multigeneration plant for generating power, fresh water, liquid hydrogen, heat, cooling and hot water is designed and investigated for possible implementation. In the design of the present system, a Kalina cycle is integrated into multigeneration plant, along with liquid hydrogen production subsystem, freshwater production subsystem, thermoelectric generator, domestic water heater, and organic Rankine cycle with a vapor compression refrigeration subsystem. According to the thermodynamic analyses performed here, energetic and exergetic efficiencies of the present multigeneration system are obtained as 46.87% and 44.13%, respectively. The total exergy destruction rate of the presently developed plant is 20,947 kW, in which the highest exergy destruction rate is observed for the Kalina cycle with about 5800 kW. Furthermore, the highest exergy efficiency occurs in the liquid hydrogen production plant as 54.17%. Moreover, eight key parameters affecting the multigeneration plant efficiency are investigated for evaluation.

Exergo-economic and exergo-environmental evaluations and multi-objective optimization of a novel multi-generation plant powered by geothermal energy

An innovative multi-generation energy system is proposed to generate simultaneous power, drinking water, cooling, heating, and H2. The aimed plant comprised of an absorption chiller, a heat pump unit, a reverse osmoses unit, a double flash cycle, and a proton exchange membrane. The devised system is surveyed comprehensively based on the thermodynamic, thermo-economic, and exergoenvironmental indicators for offering an in-depth assessment of the plant. Besides, multi-objective optimization has been employed in the proposed system. The net proportions of output work, unit cost, thermal and exergetic efficiencies, and H2, and purified water production of the system are 99.25 kW, 124 $/GJ, 24.4%, 32.1%, 1.218 kg/h, and 0.9662 kg/s, separately. The outcomes related to thermodynamic and thermo-economic evaluations demonstrate that the greatest amount of total cost rate occurred in the first employed turbine. Owing to the findings of the parametric study, by increasing geothermal temperature, exergoenvironmental parameters are reduced, and with increasing the pressure of FT1, cooling load and energetic efficiency increase while SUCP, net output work, and exergetic efficiency decrease dramatically.