Cost Of Steam Research Articles

Performance evaluation of a steam generation system using a novel semi-open heat pump for waste heat recovery in dyeing industry

In order to reduce the steam cost of dyeing industries, a steam generation system with a novel semi-open heat pump is proposed in this paper. It can recover the heat of high temperature wastewater and steam condensate simultaneously. With the use of natural refrigerant, water that is the same medium as the steam, part of the compressed steam out of the heat pump compressor can be compressed continuously by another compressor to reach the usage requirement of dyeing processes, making the steam generation system more concise. Besides, high efficiency contact condenser and water-injected twin screw steam compressor are used for the energy efficiency enhancement. Mathematic models are established and solved for the performance evaluation of the whole steam generation system. Firstly, influence of the heat pump design parameters is analyzed for performance optimization. Afterwards, performance comparison is carried out between the new steam generation system and a conventional steam generation system using heat pump with R245fa. Finally, the economic benefits by using the steam generation system in a dyeing process are discussed. Results show that the proposed system always outperforms the conventional system in thermal and economic performances. Optimal evaporation temperature exits to obtain the maximum economic benefits. With the use of novel semi-open heat pump, specific power consumption for steam generation can be as low as 188 kW h/t. By recovering the heat of 1 t/h waste water at 85 °C, the new system can generate 0.064 t saturated steam (150 °C) and about $1.02 economic benefit can be yielded, demonstrating its great development and application value.

Study on steam energy efficiency enhancement, cost management and CO2 emissions in the food industry

Malaysia's energy intensity per unit GDP has been increasing since the 1990s, leading to the government's efforts to promote energy efficiency via policies and initiatives such as Energy Performance Contracting (EPC). Additionally, the industrial sector in Malaysia consumed 28 % of total final energy in 2018, placing it as the country's second-largest final energy consumer [1]. This case study focuses on improving energy efficiency in the steam system of an existing plant in the food industry in Malaysia. This work was performed in collaboration with a local Energy Service Company (ESCO) to study the existing steam system, recognize its process requirements and constraints and consequently propose and evaluate retrofit opportunities. These opportunities were evaluated across 3 performance parameters (power output or energy savings, cost savings and CO2 emissions savings). Simulations were performed using the Steam System Modeler Tool (SSMT). The study found that Combined Heat and Power (CHP) was not feasible due to a combination of low steam pressure and flowrate available in the system. However, the study also found that improving condensate recovery coupled with condensate flashing from the high pressure to low pressure header offered the highest increments in overall performance.

Study on the Economic Operation of a 1000 MWe Coal-Fired Power Plant with CO2 Capture

The flexible operation of carbon capture units is crucial for the economic performance of coal-fired power plants equipped with CO2 capture systems. This paper aims to investigate the impact of electricity, CO2, and fuel prices on the economic operation of such plants. A novel economic optimization model is proposed, integrating a static model of the carbon capture system with a particle swarm optimization algorithm. A new concept, the CO2 boundary price, is introduced as a key metric for determining the operating conditions of CO2 capture units. The CO2 boundary price rises when the power load decreases due to the decline in power generation efficiency, and it also increases with rising fuel prices, as the cost of steam for CO2 capture increases. Additionally, when the objective is to meet power load demand, CO2 prices have a great influence on the operation of CO2 capture units, assuming fixed coal and electricity prices. However, when the primary goal is to maximize plant profitability, the system’s operational conditions are strongly influenced by the relative prices of electricity and CO2. The proposed optimization model and the uncovered price-effect mechanisms provide valuable insights into the economic operation of carbon capture power plants.

Nonlinear dynamics of a membrane reactor for hydrogen production: Multiplicity of equilibrium solutions and inhibition effects

Membrane reactors for the production of hydrogen are interesting devices that allow for the decentralized production of pure hydrogen while reducing the energy cost of the traditional steam reforming process. The performance of these systems is strongly dependent on the permeability and selectivity of the membrane employed for the separation of the produced hydrogen. Several studies have shown that the actual rate of hydrogen permeation is lower than the one that would be expected based on studies of membrane permeability carried out with pure hydrogen. This difference has been attributed to the competitive adsorption of other species, specifically CO, on the membrane surface. Here we show that this phenomenon could also lead to steady state multiplicity and analyze the dynamics of membrane reactors in the presence of competitive adsorption by CO. Emphasis has been placed on the effect of temperature and gas composition on possible multistable behavior. The results have been interpreted in terms of a transition between kinetics- and permeation-controlled regimes, in which the behavior of the reactor is limited, respectively, by the rate of the chemical reactions or the rate of hydrogen permeation.

Comparative analysis of multi-effect evaporators in an ammonium acetate concentration process for L-methionine production

The process of treating an acetic acid aqueous solution generated during L-methionine production with ammonia and recovering a highly concentrated ammonium acetate aqueous solution using a multi-effect evaporator process was studied. The electrolyte non-random two-liquid model was applied to calculate the activity in the electrolyte solution, and the Hayden-O’Connell model was used to consider the dimerization reaction of acetic acid in the vapor phase. The dissociation equilibrium constant of acetic acid was modeled based on experimental values, and all other thermodynamic property models and parameters were used as implemented in the Aspen Plus software. Economic evaluation was carried out with various sensitivity tests, considering the loss of acetic acid and ammonia, as well as the steam cost. Evaporator operation was found to be more economical when the molar ratio of acetic acid to ammonia was equal, feed concentration was high, feed flow rate was low, and evaporator temperature was low. These results were confirmed in actual plant operations, with significant correlations between the feed flow rate and evaporator temperature. Our findings have significant implications for the development of sustainable and economical L-methionine production methods that enable the recycling of ammonium acetate.

Automated steam engine technology for eco-printing batik: Empowering community economies

This community service initiative aimed to empower batik artisans in Pamekasan and Pacet villages by enhancing their economic prospects. The team disseminated automated steam engine technology for eco-printing batik to expedite the production process. The activities involved training in various aspects, including eco-printing, automated steam engine usage, cost calculation, and product branding. The outcomes revealed the unique appeal of eco-printing batik motifs, which have become a trend among environmental enthusiasts and fashionistas. The technology dissemination also streamlined the production process, allowing for 18 rolls of fabric to be steamed simultaneously, ultimately reducing production costs. Additionally, batik artisans gained the ability to determine product prices and market their creations through e-commerce platforms.

Evaluating the feasibility of direct contact membrane distillation and nanofiltration in ground water treatment through a techno-economic analysis

This study delves into the realm of water treatment by conducting a comprehensive techno-economic evaluation of direct contact membrane distillation (DCMD) and nanofiltration (NF) processes. While previous research has explored the technical aspects of membrane distillation (MD) and nanofiltration, there remains a notable gap in economic analyses. Our research aims to bridge this gap by assessing the financial feasibility of employing MD and NF technologies for water desalination. Specifically, we scrutinize the performance of hydrophobic microporous flat sheet membranes crafted from polytetrafluoroethylene (PTFE) supported by non-woven polypropylene (PP) in desalinating brackish water through DCMD and NF processes. By varying operating conditions such as flow rate and feed temperature, we evaluate the membrane's efficacy. Employing an analytical model based on heat and mass transfer equations, we predict process performance across diverse scenarios. Our model demonstrates a high level of accuracy, with flux predictions deviating by less than 10% when utilizing the Knudsen-molecular mechanism model. Furthermore, through a detailed design and economic analysis of industrial-scale units for both processes, we reveal that the cost of permeated water is lower with NF compared to DCMD. Specifically, our calculations indicate a water cost of 1.34 USD/m3 for DCMD at a feed temperature of 65 °C with an 80% recovery rate, positioning it as a competitive option among conventional desalination methods. Notably, our financial assessment highlights that steam cost constitutes the primary expense in DCMD operations, contingent upon heating value and fuel prices. Noteworthy findings suggest that natural gas emerges as the most cost-effective fuel for steam production in a DCMD plant. This study underscores the economic viability and potential cost efficiencies associated with NF over DCMD in water treatment applications.

Simulation of single-effect and triple-effect evaporator for fruit juice concentration using Aspen HYSYS

Abstract One of the most popular methods of fruit juice preservation is concentration since it offers a variety of advantages, like decreased volume, weight, packing, simpler transportation and handling, and a longer shelf life. The present paper studied the evaporation of fruit juice in single- and triple-effect evaporators using Aspen HYSYS software. The amount of juice was 3000 kg/h, and its concentration was raised from 10 to 50 °Brix. Four evaporator layouts were estimated and optimized: single-effect, modified single-effect, forward triple-effect, and triple-effect in parallel. It is a study of the effect of the temperature of saturated steam (120–300 °C) used to concentrate the juice and the pressure of the product (15–50 kPa) on the mass flow rate of steam required, economy, and overall heat transfer coefficient times area (UA) of the evaporator. The best operating conditions for each type of evaporation system were 15 kPa of the product’s pressure for all types of evaporators, 192, 240, 182, and 210 °C of the single-effect, modified single-effect, forward triple-effect, and parallel triple-effect, respectively. These operating conditions are equivalent to the steam required, economy, UA, and steam cost as follows: for each type, they were (3075, 338.4, 1224, and 1100 kg/h), (0.78, 7.1, 1.96, and 2.15), (40,182, 74,505, 539,987, 152,173 kJ/°C h), and (12.68 × 103, 12.76 × 103, 12.65 × 103, and 12.73 × 103 $/h), respectively.

Simultaneous optimization of crude oil refinery vacuum distillation column and corresponding ejector system

A vacuum distillation unit (VDU) is a relatively complex crude oil refining process that usually overlooked in researches. A detailed review of the corresponding literature reveals that most of the limited existing researches focus on either the study of the vacuum tower alone or its vacuum creating ejector system. For the first time, the combination of VDU tower and corresponding ejectors are studied in this article by resorting to coupling of Aspen-HYSYS simulation software with Ansys-FLUENT computational fluid dynamic. Both simulations were initially validated by using two sets of experimental and industrial data, borrowed from literature.Optimization of an industrial unit improved its process economics by boosting the heavy vacuum gasoil production around 38% and reducing the less valuable cut of vacuum residue by 28%, which increases the overall earnings of the optimal VDU column economics over 140 MM$/year. Furthermore, sensitivity analysis of the VDU ejector system revealed that the primary steam cost does not depend on the corresponding temperature, while, it rapidly rises, when the motive fluid pressure increases. The overall simulation results of the VDU tower and corresponding ejector system concluded that the lower primary steam pressures are more favorable both from operational and economical standpoints.

Model Based Optimization of Energy Consumption in Milk Evaporators

This work explores five falling film evaporator (FFE) simulation approaches combined with energy consumption minimization strategies, namely Mechanical Vapor Recompression and Thermal Vapor Recompression (MVR and TVR, respectively). Global system analysis and advanced dynamic optimization strategies are then investigated to minimize steam consumption, the cost of steam, and the total annualized cost and to maximize product yield. The results indicate that higher TVR discharge pressures, or MVR compression ratios, along with higher feed temperatures, enhance evaporation but increase operational costs. The most economical option includes three evaporator effects with TVR to achieve 50% product dry mass content. However, for a 35% dry mass content, MVR becomes cost-effective with an 11% reduction in unit electricity prices or a simultaneous 7% drop in electricity prices and a 5% increase in gas-based steam prices. Furthermore, switching from milk powder production to milk concentrates leads to an annual cost reduction ranging from 10.8 to 44%. Additionally, a forecasted 20% (or more) reduction in biomass-based steam cost can lead to lower annual expenditure compared with the nominal NG-based steam case. Regarding the total annualized cost, for a new plant design, optimization strategies lead to a 9–45% reduction in the total cost depending on the case under consideration.

Thermo-Economic Analysis of Gas Turbine Combined Multistage Flash (MSF) Desalination Cycle

Over the past few decades, the growth of the earth’s population has increasingly contributed to global warming, and increased demand for fresh water on top of a need for a greater power supply. This paper will analyze the integration of a combined- gas turbine with intercooler and a multi-stage flash (MSF) desalination plant for the simultaneous generation of electricity and supply of water and improved performance. The paper will also examine the calculation of the production cost and the capital cost of the MSF desalination plant. The thermo-economic analysis of the study was conducted using the IPSEpro software system. Also, exergy losses of the gas turbine and MSF desalination unit were also calculated. The desalination plant uses the exhaust gases from the gas turbine, as a form of thermal energy, and discharges to feed the seawater heater. A portion of the desalinated water is used to cool the compressed air in the intercooler heat exchanger. Results indicate the improvement in the gas turbine’s performance when desalinated water is used for the intercooler between compressor stages, as the power output increased by 59% over the the simple gas cycle and found decrease with an increase in the ambient temperature. The desalinated water cost was calculated to be $1.7 per cubic meter after determining the optimal configuration and operating conditions. A decrease in steam cost by 36% was observed when the waste heat from the gas turbine was used as the source of thermal energy. Part of this reduction can be explained by the observation that the desalination plant’s pumps consume part of the power generated by the gas turbine.

Technical-Economic Analysis of Energy Efficiency Solutions for the Industrial Steam System of a Natural Gas Processing Plant

Steam, which is primarily employed as a heat transfer medium in process plants, is one of the most widely utilized energy carriers in the industrial sector. One of the factors that affects the cost of steam is how well the condensate collection, steam supply, and return systems of industrial steam systems perform. In a case study, the steam systems of a natural gas processing plant were simulated. The amount of demineralized water loss and, consequently, the identification of various solutions to improve the system were analyzed. The whole steam system was simulated using the MEASUR software platform (v 1.2), and by placing the operational information of the steam system, it was possible to create a baseline for the system, model saving solutions, and finally, provide a technical and economic evaluation of the solutions. Due to the high loss of steam condensate in the SRU steam system (more than 3000 kg per hour), solutions to improve the energy efficiency of the SRU steam system in the form of a maximum recovery of steam condensate (replacement of defective steam traps, redesign of the low-pressure condensate collection network, and high-pressure waste condensate collection) were evaluated with two price assumptions of current energy prices and real prices (the energy saving value of one cubic meter of natural gas is equal to 13 cents). The results show that, for current prices, the investment return period will be between 11.8 and 3.8 months. Moreover, in the main steam system of the refinery (unit 9200), there are three solutions: replacing and repairing defective steam traps, installing an expansion turbine instead of a steam pressure relief valve (PRV), and other solutions (including increasing boiler efficiency, automatic control of the boiler, and energy recovery boiler blowdown) under two price assumptions, the current and real prices of natural gas and demineralized water, were evaluated, and the modeling results show that the investment return period for each of the above solutions at the current prices is 10.2, 186, and 13.3, respectively. The investment return period is based on assuming real fuel and BFW prices are equal to 2.0, 37.6, and 1.7, respectively.

Exergoeconomic assessment of a cogeneration pulp and paper plant under bi-operating modes

In the current study, the exergoeconomic analysis of a cogeneration pulp and paper plant under bi-operating modes at different environment temperatures of 290, 295, 305, 310, and 320 K was investigated. Two operating modes of the cogeneration system, i.e., a hybrid operating mode using a power boiler and a recovery boiler and a singular operating mode using a power boiler only, were considered. Natural gas was utilized as the main fuel in the power boiler, while black liquor with heavy fuel oil was employed in the recovery boiler. The total capital investment, total operating, exergy, unit exergy, and exergy destruction costs for each operating mode were evaluated. The results indicated that the total capital investment cost was 3420.27 $/h, and the total capital investment and the operation and maintenance costs in the hybrid and singular modes were 5853.27 and 6226.67 $/h, respectively. As well, the unit exergy cost and the exergy cost of steam introduced by the power boiler were 39.31 $/MWh and 2503.69 $/h, respectively. Where these values for the recovery boiler were 34.69 $/MWh and 554.30 $/h, respectively. Furthermore, the exergy destruction costs at an environment temperature of 320 K for the power and recovery boilers were 1436.6 and 213.63 $/h, respectively. In the hybrid mode, the soda at a 10% concentration was recovered, with a rate of 32 t per hour desired for the cooking process in the pulp mill. In addition, the use of black liquor as a bio-fuel in the recovery boiler saved 14% of the consumption of natural gas.

Multi-aspect study of an innovative glycerol-fed polygeneration model involving combined power cycles, chilled water unit, desalination, and methanol synthesis

The current paper presents an innovative model for a polygonation purpose based on glycerol steam reforming for the first time. This model uses an innovative thermal integration, wherein the flue gas leaving the reforming unit as well as the output syngas are considered for producing electricity, low-pressure steam, chilled water, freshwater, and methanol. This model consists of glycerol steam reforming unit, transcritical-carbon dioxide (CO2) cycle, chilled water unit, water desalination unit, steam power plant, and methanol production unit. This system was simulated using the Aspen HYSYS program, and its performance under steady-state operating circumstances was assessed using a thorough 4E analysis. The total exergy and energy efficiency are found to be 68.81 % and 35.57 %, respectively, according to the exergetic and energetic analyses. Moreover, the total rate of exergy destruction is measured at 202841 kW. Considering the environmental aspect, the system exhibits a total CO2 emission of 154,306.82 kg/h and a CO2 footprint of 0.1943 kgCO2/kgMeOH. Besides, the economic analysis exhibits that the methanol production unit has the maximum capital cost (38,298,289 $) among the equipment, contributing to 82 % of the total value. In addition, the production cost of electricity, low-pressure steam, chilled water, freshwater, and methanol is obtained at 0.088 $/kWh, 0.4 $/kgsteam, 0.026 $/kgCW, 0.12 $/kgFW, and 0.214 $/kgMeOH, respectively.

Life cycle assessment and shadow cost of steam produced by an industrial-sized high-temperature heat pump

Heat pumps are considered to be a promising technology to mitigate industrial emissions from steam provision. In this work, an existing scale-up framework for generating life-cycle inventory data for residential heat pumps was tested if applicable to large-scale high-temperature heat pumps. The benchmark was experimental data from existing machinery. It was found that the scaling framework underestimated the total mass; thus, a new scaling framework was developed and was applied to data obtained from a test run of a commercially available high-temperature pump. A full life cycle assessment was performed by comparing two different steam pressure levels, 2 and 5-bar, produced by the high-temperature heat pump to relevant benchmarks, such as steam from a fossil fuel-driven steam boiler. Although greenhouse gas emissions were reduced by as much as 98% in the best-case scenario, other midpoint categories exhibited a more mixed result in which sometimes the heat pumps were favorable and at other times the benchmarks had a lower impact. An unexpected finding was that the working fluid and its leakage did not have a significant contribution to the global warming potential but it was almost solely responsible for the ozone depletion potential. Recommendations were derived on how to further improve the environmental impact of high-temperature heat pumps. Ultimately, the life cycle impact assessment results were converted into shadow price to allow for a comparison between different areas of protection and to give policymakers an estimate of the total externalized cost of the technology.

Operating Modes Optimization for the Boiler Units of Industrial Steam Plants

The free market forces energy-intensive industrial enterprises to continuously compete. A possible competitive advantage for such enterprises is reducing the finished products cost. This may be achieved by reducing the share of energy in this cost, including by rationalizing the use of energy resources. This study develops a system for the automated analysis and calculation of feasible boiler unit loads, defined according to the criterion of the minimum cost of live steam in a separate steam plant pipeline. The calculations consider the balance limit on the steam, the boiler unit’s wear and tear, performance specifications, and economic indicators of fuel consumption in the calculation. The software also defines the optimal fuel mix composition when forecasting the operating modes of the power plant boiler units in real-time mode. The calculation algorithm is based on the dynamic programming technique combined with the sequential equivalenting method, which ensures the convergence of calculations. When a steam plant model is developed, much attention is paid to the thermal scheme and technical and economic specifications of boiler units. In the system, the boiler models are set as a table containing the ratio between the boiler unit’s steam capacity and energy consumption while considering the cost of a ton of live steam with the specified parameters. The key economic effect of implementing the system is determined by reducing the fuel cost due to its rational redistribution between the power plant boiler units. Implementing the system allows the reduction of energy costs by 1.4%.

Green steam for sustainable extraction of essential oils using solar steam generator: A techno-economic approach

Essential oils are natural volatiles extracted using steam. Steam generation is an energy-intensive process and is invariably based on fossil fuels, briquettes or biomass. Based on the volumes of essential oil extracted, it can be considered as significant contributor to greenhouse gases. Though a lot of work is reported on essential oil extraction and characterisation, method for quantification of exact steam requirement and means for achieving it through sustainable source is not much reported.Through this study, steam requirement of 750 g/ml of Betel leaf volatile oil extracted and quantification of energy requirements for the extraction process is determined. For adoption of sustainable and clean energy source, opto-geometric optimisation and concentrating solar collectors (CSC) area calculation are carried out. The design of three CSC, namely, Linear Fresnel Reflector (LFR), parabolic dish collector (PDC) and parabolic trough collector (PTC), resulted in 78 m2, 122 m2 and 138.87 m2 of area to meet the steam requirement of the process.Adoption of CSC technologies for steam generation and replacing the prevalent technology needs detailed analysis and techno-economic comparison. This paper also focuses on cost-benefit analysis, taking into account CAPEX, OPEX, life-span, return on investment, levelized energy (steam) cost and the profitability index of net present value, payback period and internal rate of returns to check the economic feasibility of renewable energy. Analysis indicates that the cost associated with unit steam generation through CSC over the specified period is lower than a briquette-based steam generation. On adopting this sustainable technology for betel leaf oil extraction, even if the initial cost seems to be high, the payback period of LFR and PTC are 1.10 and 2.45 years, respectively. Based on this study, CSCs can provide a sustainable green solution for the extraction of essential oils.

Exergetic assessment and exergoeconomic diagnosis of a sugarcane plant in northeastern Brazil

The increase in industrial needs increased the demand for fuels, electricity and the growth of climatic effects. This study performs an exergoeconomic evaluation in a sugar, ethanol and electricity production plant located in the Northeast of Brazil. The objective is to identify thermoeconomic inefficiencies, exergy destruction and efficiencies, determine the costs of exergy flows and a step by step of exergoeconomic diagnosis using the SPECO method. The results show the greatest inefficiencies presented in boiler 1 (48 MW, 28%), boiler 2 (43 MW, 25%) and boiler 3 (31 MW, 18%). The production of steam costs R$63.88 for each GJ of energy. The total cost of exergy destruction in the boilers is R$3,808 per hour of operation which means about 84% of all exergy destroyed in the plant. The exergoeconomic diagnosis concludes that the equipment that needs optimisation primarily is the deaerator (5,904% rk) and the condenser (1,674% rk).

Kondenstopların Enerji Verimliliğine Etkileri ve Enerji Maliyet Analizi: Bir Tekstil Firması Örneği

Buharı kullanan ve buhar hatlarının yoğun olduğu çeşitli endüstriyel tesislerde, kondenstoplar enerji verimliliği için oldukça önemli ekipmanlardır. Çalışmamızda kondestopların çeşitleri, kullanım özellikleri ve uygulamada karşılaşılan aksaklıklar (montaj, ebatları, malzeme uygunluğu, çalışma şartları) bakımından en çok görülen kondenstop problemleri anlatılmaktadır. Genel kondenstop problemlerinin oluşum nedenleri, bakım ve onarım için yapılması ve dikkat edilmesi gerekenler ayrıntılı açıklanmaktadır. Bir endüstriyel tesisin buhar hatlarının kayıp ölçümü ve kondenstopların enerji kayıp maliyetleri hesaplanarak, ekonomik önemleri de gösterilmektedir. Analizler sonucunda, 105 kondenstop olan fabrikanın kondenstoplardan bir yıllık enerji kayıp maliyetinin 561,384 USD olduğu, bakım ve tamir işlemlerinden sonra 93,287 USD düştüğü tespit edilmiştir.

Hydrogen production and separation in fuel-rich operated HCCI engine polygeneration systems: Exergoeconomic analysis and comparison between pressure swing adsorption and palladium membrane separation

Hydrogen is one of the most important base chemicals and discussed as a future energy carrier for power and heat generation, as well as energy storage. Producing hydrogen at low costs and low CO2 emissions is thus of increasing importance. This study addresses the thermodynamics and economics of hydrogen, power, and heat generation by partial oxidation of methane in fuel-rich operated homogeneous charge compression ignition (HCCI) engines. Therefore, a python model of two different process concepts with different hydrogen separation technologies was developed and analyzed: pressure swing adsorption (PSA) and palladium membrane separation. The operating conditions of the engine and the separation were evaluated by conducting a global sensitivity analysis. The most suitable engine operating parameters were found at an equivalence ratio of 2, an intake temperature of 200 °C, a rotational speed of 1500 1/min, and a compression ratio of 22. In direct comparison, PSA consistently yielded better results than the palladium membrane, and low feed pressures were favorable. Subsequently, the uncertainty of economic input values was investigated and the power and hydrogen costs evaluated. In the PSA case, the electricity and hydrogen costs were found in a range of 44.2 €/MWh to 97.6 €/MWh and 2.7 €/kg to 7.2 €/kg, respectively, with an overall exergetic efficiency of 68.3%. Therefore, the proposed polygeneration system provides electricity at competitive costs and hydrogen at costs similar to a small-scale steam reforming plant at comparable efficiencies. Further scaling up of the engine could provide hydrogen at the cost of large-scale steam reforming, making the proposed concept a promising alternative.