Supercritical Carbon Dioxide Power Cycle Research Articles

500℃ 터빈 입구 조건의 수백 kWe급 초임계 이산화탄소 발전시스템 테스트루프 개발 연구

한국에너지기술연구원에서는 바이오매스 및 폐열과 같은 분산 전원에 적합한 수백 kWe급 초임계 이산화탄소 발전사이클 테스트루프를 개발 중에 있다. 터빈 2기, 압축기, 복열기 2기, 연소배가스 이용 히터로 구성된 120kWe 용량의 이중 브레이튼 사이클을 개발하였으며, 목표 터빈 입구 조건은 500℃/135bar이다. 미캐니컬 씰과 틸팅패드 베어링으로 구성된 충동형 축류 터보-발전기는 2017년에 이미 제작, 시험을 성공적으로 완료하였다. 다음 단계로 드라이가스씰(DGS)이 적용된 원심형 압축기를 개발하였으며, 버너와 쉘앤튜브 열교환기로 구성된 650℃의 연소배가스 이용 히터를 제작하고, ASME 기준에 따라 배관 설계를 진행하였다. 전체 테스트루프는 올해 완성 및 운전을 목표로 하고 있다.

Calcium-based composites for direct solar-thermal conversion and thermochemical energy storage

Calcium-Looping (CaL) is considered as a promising process for thermochemical energy storage in the 3rd generation Concentrated Solar Power plants using a supercritical carbon dioxide power cycle. Here we propose, for the first time, a novel strategy to directly absorb solar energy using calcium-based composite thermochemical energy storage (TCES) materials. The main novelty lies in the binary metallic element doping of the calcium-based raw materials to enhance their direct interactions with solar radiation photons for light capturing. In particular, the use of the metallic element doping is to form high light-absorbing material for addressing the unfavorable intrinsic optical absorption properties of the calcium carbonate for photon management. A simple and facile sol-gel method was used to synthesize the CaO composites doped with Mn and Fe. Such binary metallic element doping into the calcium-based materials not only boosted the solar absorption but also improved the cycling stability of the TCES material in the integrated CaL-CSP system. The synthetic composites were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The effects of thermochemical cycling on the microstructures and properties of TCES material were investigated. Furthermore, the underlying mechanisms were discussed. The results indicated that the enhancement of the optical absorption for the composites originated from metal oxides of Fe and Mn with high light-absorbing ability. The synergistic effects of small grain size and the reinforced skeleton structures could impede agglomeration and collapse of the composites, thereby improving the cycling stability.

Thermal performance and economic analysis of supercritical Carbon Dioxide cycles in combined cycle power plant

A closed-loop, indirect, supercritical Carbon Dioxide (sCO2) power cycle is attractive for fossil-fuel, solar thermal and nuclear applications owing to its ability to achieve higher efficiency, and compactness. Commercial Gas Turbines (GT’s) are optimised to yield maximum performance with a conventional steam Rankine cycle. In order to explore the full potential of a sCO2 cycle the whole plant performance needs to be considered. This study analyses the maximum performance and cost of electricity for five sCO2 cascaded cycles. The plant performance is improved when the GT pressure ratio is considered as a design variable to a GT to optimise the whole plant performance. Results also indicate that each sCO2 Brayton cycle considered, attained maximum plant efficiency at a different GT pressure ratio. The optimum GT pressure ratio to realise the maximum cost reduction in sCO2 cycle was higher than the equivalent steam Rankine cycle. Performance maps were developed for four high efficient cascaded sCO2 cycles to estimate the specific power and net efficiency as a function of GT turbine inlet temperature and pressure ratio. The result of multi-objective optimisation in the thermal and cost (c$/kWh) domains and the Pareto fronts of the different sCO2 cycles are presented and compared. A novel sCO2 cycle configuration is proposed that provides ideal-temperature glide at the bottoming cycle heat exchangers and the efficiency of this cycle, integrated with a commercial SGT5-4000F machine in lieu of a triple-pressure steam Rankine cycle, is higher by 1.4 percentage point.

Optimal allocation of heat exchangers in a Supercritical carbon dioxide power cycle for waste heat recovery

Supercritical carbon dioxide (sCO2) power cycles have attracted attention because of their high efficiency and flexibility in various temperature heat sources including low-temperature waste heat applications. In waste heat applications, the size of the heat exchangers is an important issue because of the trade-off between performance and installation cost. For the optimal design of an sCO2 cycle for waste heat recovery, a thermodynamic model for the basic cycle and the preheating cycle was constructed. The heat exchangers were then modeled by a finite volume analysis under the fixed total UA value, with the equivalent conductance representing the size of the heat exchanger. The net power and thermal efficiency of the cycle were calculated. The results of the optimization confirmed that the application of the preheater improves the performance of the basic cycle, and an optimum point of the split ratio exists. From the simulation, with an increase in the turbine inlet temperature (TIT), the thermal efficiency improves, but the net power does not always increase. Instead, a close linearity between the optimum CO2 split ratio (ϕ) and the turbine inlet temperature was found at the maximum net power, even under different turbine inlet pressures and total UA values. From these results, the configuration of heat exchangers for waste heat applications can be planned appropriately to operate at the maximum net power.

Comparative energy, exergy and exergo-economic analysis of solar driven supercritical carbon dioxide power and hydrogen generation cycle

Parabolic dish solar collector system has capability to gain higher efficiency by converting solar radiations to thermal heat due to its higher concentration ratio. This paper examines the exergo-economic analysis, net work and hydrogen production rate by integrating the parabolic dish solar collector with two high temperature supercritical carbon dioxide (s-CO2) recompression Brayton cycles. Pressurized water (H2O) is used as a working fluid in the solar collector loop. The various input parameters (direct normal irradiance, ambient temperature, inlet temperature, turbine inlet temperature and minimum cycle temperature) are varied to analyze the effect on net power output, hydrogen production rate, integrated system energetic and exergetic efficiencies. The simulations has been carried out using engineering equation solver (EES). The outputs demonstrate that the net power output of the integrated reheat recompression s-CO2 Brayton system is 3177 kW, whereas, without reheat integrated system has almost 1800 kW net work output. The overall energetic and exergetic efficiencies of former system is 30.37% and 32.7%, respectively and almost 11.6% higher than the later system. The hydrogen production rate of the solarized reheat and without reheat integrated systems is 0.0125 g/sec and 0.007 g/sec, accordingly and it increases with rise in direct normal irradiance and ambient temperature. The receiver has the highest exergy destruction rate (nearly 44%) among the system components. The levelized electricity cost (LEC) of 0.2831 $/kWh with payback period of 9.5 years has proved the economic feasibility of the system design. The increase in plant life from 10 to 32 years with 8% interest rate will decrease the LEC from (0.434-0.266) $/kWh. Recuperators have more potential for improvement and their cost rate of exergy is higher as compared to the other components.

Investigation on steady aerodynamic performance of a S-CO2 compressor with different diffusers in solar power system

Research on solar power system has become a hot spot recently. The supercritical carbon dioxide (S-CO2) power cycle has been widely used in the solar power system with excellent advantages of high efficiency and small device size. Centrifugal compressor plays an important role in the S-CO2 power cycle. The design of a centrifugal compressor is completed according to the requirements of thermal design in this paper. The differences of three kinds of diffusers on the steady aerodynamic performance are further investigated based on the designed model. Finally, the influence of diffuser blade number on the performance is discussed. The results show that the centrifugal compressor with wedge-shaped diffuser holds the best performance under the design and off-design conditions. The diffuser blade number has significant influence on the aerodynamic performance. The current design and performance analysis of centrifugal compressor could provide important reference value for further application of centrifugal compressor in solar power system.

A thermodynamic analysis of a solar hybrid coal-based direct-fired supercritical carbon dioxide power cycle

Efficient utilization of coal for power generation with carbon capture as well as development of solar hybrid system are being aggressively researched currently. To advance the utilization of solar energy and achieve zero emission for coal-based power generation more efficiently, a novel direct-fired, oxy-combustion supercritical carbon dioxide power cycle integrated with the solar-driven coal gasification was proposed. In the proposed system, the concentrated solar energy is utilized for coal gasification, and then the produced syngas is combusted with high-purity oxygen to drive a semi-closed supercritical carbon dioxide power cycle with intensive heat recuperation and near-zero carbon emission. Detailed analytical models based on energy and material balance were developed and the overall system thermodynamic performance were determined by the process simulation. Results showed that, at the designate point, the proposed system can save 29.9% of coal consumption and the net system energy efficiency and exergy efficiency soar to 43.4% and 44.6%, respectively; and the annualized coal saving can reach 10.46 kilo tonnes with the annual solar-to-electricity efficiency at 16.9%. The proposed concept may provide a new approach to advancing solar-coal hybridization power generation with near-zero emission.

Computational investigations on convective flow and heat transfer of turbulent supercritical CO2 cooled in large inclined tubes

Considering the gap between the demanded expertise for the design of A-frame heat exchanger bundles used in advanced supercritical carbon dioxide (sCO2) power cycles and the limited relevant research work, computational research on cooling turbulent sCO2 flows in various inclined tubes with diameter of 20mm has been performed in this paper. The AKN low-Reynolds number k-ε turbulence model was used and validated against the experimental measurements published in literature for sCO2 heat transfer in large pipes. Using the examined RANS model, the details of turbulent sCO2 flow and heat transfer were presented, where various inclination angles, flow directions and heat fluxes were issued. The results demonstrate that the AKN model gives good consistency with the test results. The buoyant force affects the flow characteristics of turbulent sCO2, which can be decomposed into two components. The mainstream-parallel buoyancy trends to deform the velocity and turbulence distributions of bulk sCO2 flows, while the other component that is perpendicular to mainstream is to induce a secondary flow and generate the asymmetrical flow fields. Turbulent sCO2 flow features are determined based on the combined effect of both components. The heat transfer coefficient distributions were displayed based on the simulations. At Tb>Tpc, the forced convection is dominant and the heat transfer coefficients of various geometries do not change much. At Tb<Tpc, the buoyancy effect grows and the heat transfer coefficients differentiate between various orientations, which gets more pronounced with rising heat flux. However, compared with the influence of buoyancy on heat transfer performance exhibited in small tubes in literature, the heat transfer coefficients of turbulent sCO2 flows are less sensitive to the buoyancy, even at moderate/low mass fluxes.

Design and Analysis of S-CO2 Cycle and Radial Turbine for SOFC Vehicle Waste-Heat Recovery

Solid oxide fuel cell (SOFC) vehicles are considered to have broad prospects for development, and the high operating temperature of SOFC results in great potential for waste-heat recovery. Many concepts for utilizing waste heat of SOFC have been suggested and studied, and most of them directly couple an SOFC to a gas turbine, which require the SOFC to operate at an elevated pressure and make the system less flexible and thus harder to operate. In recent years, with the development of turbine and heat exchanger technology, the supercritical carbon dioxide (S-CO2) power cycle has raised widespread attractions for the waste recovery. This study explores the potential of S-CO2 Brayton cycle to realize waste-heat recovery for an SOFC vehicle. The SOFC can operate at atmospheric pressure, and the hybrid system is easier to operate than the directly coupled systems. In this paper, a simple recuperated S-CO2 Brayton cycle is proposed and the key component, radial inflow turbine is designed and focused. The flow state of the designed turbine is analyzed in detail based on computational fluid dynamics (CFD) numerical simulation. Five cases with different impeller tip clearances are numerically simulated to study its influence on the turbine performance. In addition, off-design performance analysis of the radial inflow turbine is conducted considering the temperature fluctuation of SOFC in practical applications.

Measurement of methane autoignition delays in carbon dioxide and argon diluents at high pressure conditions

The directly fired supercritical carbon dioxide (sCO2) power cycle has high efficiency while allowing nearly complete carbon dioxide (CO2) capture. The operating conditions of sCO2 power cycle (100–300 bar) combustors are dramatically different from conventional gas turbine combustors. However, combustion properties such as autoignition delay are not well understood at these conditions. This study reports methane autoignition delay measurements for diluted carbon dioxide environments at 100 and 200 bar and at temperatures within the range of 1139–1433 K using a high pressure shock tube. To study the effect of CO2 on ignition, similar experiments are conducted at 100 and 200 bar by replacing carbon dioxide with argon. The experimental data is then compared with calculations using different chemical kinetics models. For the conditions of this study, predictions of the Aramco Mech 2.0 show the overall best agreement with experimental measurements, while predictions of the GRI 3.0 kinetic model have the largest (by a factor of 3) deviation with experiments. Sensitivity and reaction pathway analyses reveal that methyl (CH3) recombination to form ethane (C2H6) and oxidation of CH3 to form methoxide (CH3O) are the most important reactions controlling the ignition behavior at temperatures greater than approximately 1250 K. However, at temperatures below approximately 1250 K, an additional reaction pathway for methyl radicals is found through CH3+O2+M = CH3O2+M which leads to formation of methyldioxidanyl (CH3O2). This reaction pathway plays a distinct role in dictating the ignition trends at lower temperature conditions.

Capital Cost Assessment of Concentrated Solar Power Plants Based on Supercritical Carbon Dioxide Power Cycles

Previous work by the authors has shown that broader analyses than those typically found in literature (in terms of operating pressures allowed) can yield interesting conclusions with respect to the best candidate cycles for certain applications. This has been tested for the thermodynamic performance (first and second laws) but it can also be applied from an economic standpoint. This second approach is introduced in this work where typical operating conditions for concentrated solar power (CSP) applications (current and future generations of solar tower plants) are considered (750 °C and 30 MPa). For these, the techno-economic performance of each cycle is assessed in order to identify the most cost-effective layout when it comes to the overnight capital cost (OCC). This analysis accounts for the different contributions to the total cost of the plant, including all the major equipment that is usually found in a CSP power plant such as the solar field and thermal energy storage (TES) system. The work is, thus, aimed at providing guidelines to professionals in the area of basic engineering and prefeasibility study of CSP plants who find themselves in the process of selecting a particular power cycle for a new project (set of specifications and boundary conditions).

Thermodynamic analysis of a novel oxy-combustion supercritical carbon dioxide power cycle integrating solar-driven coal gasification

To advance the utilization of both coal resources and solar energy, a novel oxy-combustion supercritical carbon dioxide (sCO2) power cycle with solar-driven coal gasification integration was proposed and analyzed. In the proposed system, the concentrated solar energy is utilized for coal gasification to produce syngas for oxy-combustion to drive sCO2 power cycle with near-zero emission and the heat from air separation and hot syngas is recovered for coal drying, steam generation and sCO2 heating in a cascade way. Through introducing solar heat for coal gasification, the raw coal consumption is reduced and the oxygen production process can be eliminated, leading to a higher net system efficiency. The oxy-combustion power cycle can also be simplified owing to the better matching between the process waste heat and the steam generation for gasification. Detailed thermodynamic analysis showed that, the proposed system can save 28.3% of coal consumption with the net efficiency improvement of 1.6 percentage points, compared with the reference system. The solar-to-electricity efficiency can also reach as high as 23.3%.

Supercritical carbon dioxide power cycle design and configuration optimization to minimize levelized cost of energy of molten salt power towers operating at 650 °C

This analysis investigates the design, cost, and performance of the simple, recompression, and partial-cooling configurations of the supercritical carbon dioxide power cycle integrated with a molten salt power tower concentrating solar power system. This paper uses a steady-state model to design each cycle with varying amounts of recuperator conductance to understand performance and cost trade-offs. The recompression cycle can achieve a higher thermal efficiency than the partial-cooling cycle, and the partial-cooling cycle achieves a higher thermal efficiency than the simple cycle. The partial-cooling cycle is the most expensive cycle because it requires more total turbomachinery capacity. However, the partial-cooling cycle has the largest temperature range of heat input. This feature leads to cheaper two-tank thermal energy storage, higher receiver efficiencies, and lower mass flow rates in the power tower. Crucially, the lower mass flow rates significantly reduce pump electricity consumption relative to the recompression-cycle system. Consequently, this study finds that the power tower system integrated with the partial-cooling cycle is both cheaper and generates more net electricity than systems integrated with the other two cycles. Finally, this paper presents a parametric study on the air-cooler approach temperature and shows that small approach temperatures can improve cycle efficiency and increase the temperature range of heat input, which can lead to smaller optimal approach temperatures than may be expected.

Thermo-economic assessment of biomass gasification-based power generation system consists of solid oxide fuel cell, supercritical carbon dioxide cycle and indirectly heated air turbine

This study energetically, exergetically and economically analyses a hybrid electricity generation system. The proposed system is a combination of a biomass gasifier, a solid oxide fuel cell module, an indirectly heated air turbine and a supercritical carbon dioxide power cycle. Influences of major designing and operating plant parameters, viz. current density of the solid oxide fuel cell, pressure ratio of the air compressor, turbine inlet temperature of the CO2 gas turbine, on the performance of the proposed system have been examined. The proposed system exhibits the highest first law efficiency of 51% at the current density of 2000 A/m2 and cell temperature of 1123 K, air compressor pressure ratio of 4.4, CO2 gas turbine inlet pressure and temperature of 10.14 MPa and 423 K. At this aforesaid condition, the proposed system exhibits a second law efficiency of 45%. It is found that the highest amount (40.70%) of exergy destruction takes place at the biomass gasifier, followed by the solid oxide fuel cell (20.05%). The economic analysis predicts that the minimum achievable levelized unit cost of electricity is 0.095 $/kWh.

Investigation of leakage reinjection system for supercritical CO2 power cycle using heat pump

Supercritical carbon dioxide power cycle (sCO2) has recently attracted a great deal of interest owing to its compact size and potential for achieving high efficiency over a wide temperature range. However, several challenges still need to be overcome before the sCO2 cycle can be commercialized. One such challenge is leakage at the rotor components. The present paper discusses an innovative heat-pump application that can be used for leakage reinjection. The unique consideration of this leakage supplement system for the supercritical CO2 cycle stems from the high energy density of sCO2 and the high rotational speeds seen in turbomachinery. This paper proposes a heat-pump system that collects CO2 leakage at the turbine and liquefies this gas at the evaporator. The liquefied CO2 is then pressurized to the high pressure required for the main power generating cycle, and subsequently heat from the heat-pump working fluid is transferred to the CO2 in the heat-pump condenser. This heat-pump system offers superior compression performance over conventional methods of reinjection. Thermodynamic analysis reveals that the performance of the heat-pump system is sensitive to the saturation temperature of CO2 in the evaporator and superheating at the heat-pump's compressor inlet. Then, the genetic algorithm optimization module in MATLAB is used to optimize the system for net power consumption. Various heat-pump working fluids are investigated; R290 (Propane) delivers the best performance at 38.9% reduction in net power compared to a base case.

Design and dynamic modeling of printed circuit heat exchangers for supercritical carbon dioxide Brayton power cycles

Due to the unique geometries and hydraulics of printed circuit heat exchangers and rapidly changing properties of supercritical carbon dioxide, the effective design and rating of printed circuit heat exchangers is an essential requirement for their use in supercritical carbon dioxide power cycles. In this study, one-dimensional design and dynamic models have been developed in Aspen Custom Modeler for printed circuit heat exchangers utilized in printed circuit heat exchangers Brayton power cycles. The design model is used to determine the optimal geometry parameters by minimizing the metal mass. The dynamic model is used to predict transient behavior and can be easily implemented into system-level models developed in Aspen Plus Dynamics for cycle performance evaluations. In these models, the heat transfer coefficient and friction factor are calculated using data reported by Heatric, a prominent printed circuit heat exchanger manufacturer. Both models are validated by comparing with the data from a small-scale exchanger used in the 100 kWe facility operated by the Naval Nuclear Laboratory, and then applied to design and simulate low- and high-temperature recuperators for a 10 MWe supercritical carbon dioxide indirect recompression closed Brayton cycle, which is of interest to the U.S. Department of Energy. The designs and dynamic responses of the printed circuit heat exchangers are compared with conventional shell-and-tube exchangers and microtube shell-and-tube exchangers for the same applications. The simulation results indicate that the proposed printed circuit heat exchangers have fast dynamic responses due to their small metal masses and high heat transfer coefficients compared with the conventional shell-and-tube exchangers. Even though the metal masses of the designed PCHEs are slightly higher than those of the microtube shell-and-tube exchangers, the printed circuit heat exchangers are still promising candidates for heat recuperation because of their mature manufacturing procedures and abundant laboratory and industrial operating experience.

Analysis of a recompression supercritical carbon dioxide power cycle with an integrated turbine design/optimization algorithm

A cycle simulation code with integrated turbine design/optimization algorithm has been developed and utilized for the analysis/optimization of ≈10MWe recompression supercritical carbon dioxide Brayton cycle. Integrated turbine design and optimization code computes the turbine design engaging the meanline design calculations as a function of received inlet conditions from the main cycle simulation code. Moreover embedded turbine code optimizes the turbine geometric by minimized the losses with in the turbine using response surface optimization methodology and returns turbine geometry and performance parameters to main code. In order to capture the swift variation in thermophysical properties of SCO2 in the supercritical region, cycle design point code and embedded turbine codes are linked with NIST REFPROP program. Integrated turbine design/optimization code was validated using 3D Reynolds-Averaged-Navier-Stokes calculations. Response surface methodology was tested by comparing the 3D computation results for the turbine baseline and optimized designs. Finally recompression supercritical carbon dioxide Brayton cycle was analyzed under various conditions of cycle's minimum temperature, minimum pressure, and pressure ratio and split mass fraction. On the basis of the results it is recommended to use proposed model for more realistic and accurate modeling cycle design point analysis.

A thermo-economic methodology to select sCO2 power cycles for CSP applications

The interest in Supercritical Carbon Dioxide (sCO2) power cycles has grown exponentially in the last decade, thanks to distinctive features like the possibility to achieve high thermal efficiencies at intermediate temperature, small footprint and adaptability to a wide variety of energy sources. In the present work, the potential of this technology is studied for Concentrated Solar Power applications, in particular Solar Tower systems with Thermal Energy Storage.Further to a previous thorough sensitivity analysis of twelve sCO2 cycles assessing the impact of turbine inlet temperature and pressure ratio on thermal efficiency, specific work, solar share and temperature rise across the solar receiver, the present paper investigates the features of two of these cycles in more detail. The most important conclusions of this section are that: a) the peak values of these thermodynamic figures of merit are obtained at different pressure ratios; b) specific work and temperature rise across the receiver seem to follow parallel trends whilst this is not the case for thermal efficiency; c) for a given turbine inlet temperature, higher pressure ratios increase the temperature rise across the receiver strongly, but the effect on thermal efficiency is uncertain as this can either increase or decrease, depending on the cycle considered.A deeper analysis of thermal efficiency and receiver temperature rise is therefore mandatory, given that these parameters have a very strong effect on the capital cost of CSP power plants. On one hand, a higher thermal efficiency implies a smaller solar field, the largest contributor to the plant capital cost; on the other, the temperature rise across the receiver is inversely proportional to the size of the thermal energy storage systems, as it is also the case for state of the art steam turbine based CSP plants. In order to quantify these trends, an economic analysis is developed using an in-house code and the open-source software System Advisor Model to evaluate the trade-offs between these two effects. As a result, the Overnight Capital Cost is estimated at some 5000 $/kW, with the individual contributions of solar field, thermal energy storage and power block being given in the paper.

High-Temperature Oxidation of Commercial Alloys in Supercritical CO2 and Related Power Cycle Environments

The oxidation behavior of several Fe and Ni commercial alloys was evaluated in high-temperature environments expected in next-generation supercritical carbon dioxide power cycles. The alloys were exposed to pure CO2 at 0.1 and 20 MPa and to CO2 containing H2O, O2, with and without SO2 at 0.1 MPa, at temperatures of 550°C (Fe alloys) and 700–750°C (Ni alloys). For comparison, the alloys were also exposed to air and supercritical steam. Low-Cr ferritic Fe alloys formed Fe-rich oxides leading to high oxidation rates in pure CO2, while high-Cr austenitic Fe alloys formed Cr-rich oxides leading to low oxidation rates. H2O and O2 impurities had negligible effect on the oxidation behavior of all Fe alloys. The addition of SO2 had negligible effect on the oxidation of ferritic Fe alloys, but significantly enhanced the rate for austenitic Fe alloys, where S in the oxide and underlying alloy contributed to the transition from Cr-rich to Fe-rich oxide growth. Ni alloys formed Cr-rich oxides and showed low oxidation rates in all CO2-containing environments which were very similar to those obtained in air and supercritical steam. Little or no effect of pressure was observed for any of the alloys exposed to pure CO2.

Optimal feed flow sequence for multi-effect distillation system integrated with supercritical carbon dioxide Brayton cycle for seawater desalination

Abstract Multi-effect distillation is often integrated with a Rankine power cycle for cogeneration (simultaneous production of power and desalinated water). Such integration increases the condenser operating pressure for the Rankine cycle (and increases the heat-rejection temperature) to produce desalinated water, resulting in decreased power-plant efficiency. The supercritical carbon dioxide Brayton cycle has a higher efficiency compared to the Rankine cycle. The waste heat rejected from supercritical carbon dioxide Brayton cycle is at sufficiently hot temperature to have feasible energy integration with multi-effect distillation system. The paper introduces the novel concept of cogeneration without being a parasitic load to the power cycle. For the illustrative example considered, integrating 4-effect distillation system with a 115 MWe power plant can produce 3041 m3 of distillate per day at 1.06 $/m3, at a constant power plant efficiency of 49.2%. The pattern in which feed enters the desalination system often dictates its energy consumption. The two most commonly used feed configurations for multi-effect distillation system are parallel/cross feed and forward feed. With steam as a heat source (i.e., a latent heat source), parallel/cross feed is the most energy-efficient feed configuration. The other objective of this paper is to identify the optimal feed flow configuration for multi-effect distillation system integrated with a supercritical carbon dioxide power cycle (i.e., a sensible heat source). For the simplified network, forward feed is the best feed configuration, which yields a 7.5% increase in distillate production at 2.6% reduced distillate cost. Additionally, different methods for reducing the brine discharge are studied, which can help to achieve zero liquid discharge. Result show increasing the maximum brine concentration gives superior results compared to brine recycling. The system modelling is done using the principle of process integration, and an analytical methodology for cogeneration is derived.