Pub Date : 2026-03-20DOI: 10.1016/j.enconman.2026.121370
Shiyang Teng, Dou An, Xun Chen, Huan Xi
{"title":"Multi-parameter optimization of Tesla turbine for small-scale ORC systems: an experimentally validated general predictive framework","authors":"Shiyang Teng, Dou An, Xun Chen, Huan Xi","doi":"10.1016/j.enconman.2026.121370","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121370","url":null,"abstract":"","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"6 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147496136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-17DOI: 10.1016/j.enconman.2026.121365
Lin Chen, Lingzhi Zhu, Haiqiao Wei
Apart from the well-established infrastructures, ammonia can be synthesized through a green process and serves as a green fuel. Co-combustion with methanol (another green fuel) has been proven to be a simple and efficient solution to overcome the poor combustion performance of ammonia. This study proposes a new approach to enhance ammonia combustion by combining spark-ignited (SI) combustion with following methanol spray combustion (SISC). Its combustion and flame characteristics are optically studied at an engine speed of 1000 RPM. The results show that ammonia addition can promote ammonia SI combustion, however, the combustion initiation timing remains nearly unchanged when the methanol ratio exceeds 10%. Namely, an early spark timing is still required to ensure a stable combustion. The SISC mode enables the decoupling of methanol’s promotional effects on early- and late-stage combustion, while simultaneously achieving a significant enhancement of late-stage combustion. At a high methanol ratio of 15%, the SISC mode can further improve the combustion efficiency by 5.4% (IMEP, from 5.71 bar to 6.02 bar). However, the early combustion of SISC gets worse, which reduces the combustion efficiency in cases with a low methanol ratio. Flame images confirm that the SISC mode weakens the early flame (less fuel), and strengthens the late flame during the spray. Besides, the methanol spray flame can superimpose on the former SI flame at a high speed of 50 m/s. As a result, the flame intensity can be significantly enhanced during the late combustion, which is the main reason for the improved combustion efficiency at a high methanol ratio. As for the nitrogen-based emissions, both the NH3 and NOX can be reduced by the SISC mode.
{"title":"Enhancing ammonia combustion by combining SI combustion with following methanol spray combustion","authors":"Lin Chen, Lingzhi Zhu, Haiqiao Wei","doi":"10.1016/j.enconman.2026.121365","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121365","url":null,"abstract":"Apart from the well-established infrastructures, ammonia can be synthesized through a green process and serves as a green fuel. Co-combustion with methanol (another green fuel) has been proven to be a simple and efficient solution to overcome the poor combustion performance of ammonia. This study proposes a new approach to enhance ammonia combustion by combining spark-ignited (SI) combustion with following methanol spray combustion (SISC). Its combustion and flame characteristics are optically studied at an engine speed of 1000 RPM. The results show that ammonia addition can promote ammonia SI combustion, however, the combustion initiation timing remains nearly unchanged when the methanol ratio exceeds 10%. Namely, an early spark timing is still required to ensure a stable combustion. The SISC mode enables the decoupling of methanol’s promotional effects on early- and late-stage combustion, while simultaneously achieving a significant enhancement of late-stage combustion. At a high methanol ratio of 15%, the SISC mode can further improve the combustion efficiency by 5.4% (IMEP, from 5.71 bar to 6.02 bar). However, the early combustion of SISC gets worse, which reduces the combustion efficiency in cases with a low methanol ratio. Flame images confirm that the SISC mode weakens the early flame (less fuel), and strengthens the late flame during the spray. Besides, the methanol spray flame can superimpose on the former SI flame at a high speed of 50 m/s. As a result, the flame intensity can be significantly enhanced during the late combustion, which is the main reason for the improved combustion efficiency at a high methanol ratio. As for the nitrogen-based emissions, both the NH<ce:inf loc=\"post\">3</ce:inf> and NO<ce:inf loc=\"post\">X</ce:inf> can be reduced by the SISC mode.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"48 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-17DOI: 10.1016/j.enconman.2026.121342
Aslı Akyol Inada, Devrim Aydin, Saffa Riffat
In the last decade, low-grade thermochemical energy storage systems have been gaining interest due to their long-term heat storage potential and high energy storage density. Despite the advantageous aspects of this heat storage method, previously investigated fixed-bed reactors suffer from low heat and mass transfer performance and offer limited process control. In order to overcome these challenges, a new multi-layer moving bed reactor was designed, manufactured, and tested in this study. The proposed reactor consists of reaction and storage sections where eight independent sorption beds have freedom of movement between the two sections. Such a design enables a modular concept, where each sorption bed could be charged or discharged individually, while the remaining sorption beds are stored inside their own hermetically insulated chambers. In the system, two different sizes of pumice stones, namely PM1 and PM2, were used as the host matrix, and three different thermochemical materials were synthesized by impregnation of the LiCl-CaCl2 mixture and CaCl2 as salts into pumice. During the experiments, comparative analyses of different materials, short-cycle full-system analyses, long-cycle energy density analyses, and multi-bed performance analyses have been performed. Additionally, the impact of air velocity was investigated. The evaluations were performed based on the First and Second Laws of Thermodynamics. Study results demonstrated that each sorption bed provides an average heat output between 0.58 and 1.07 kW depending on the inlet air conditions and the composition of thermochemical material. According to the study results, the energy storage density of the system was obtained as 189.7 kWh/m3 with the use of PM2-CaCl2. On the other hand, 4.2 m/s was found as the most optimal air velocity, proving the highest average heat output during the discharging process and the highest moisture desorption rate per unit of heat consumed during the charging process. A linear correlation between the air absolute humidity difference and the air temperature lift for the discharging process was also obtained, which could provide useful insights for the performance prediction of thermochemical energy storage systems.
{"title":"Experimental study of a novel multi-layer moving bed reactor for low-grade thermochemical energy storage","authors":"Aslı Akyol Inada, Devrim Aydin, Saffa Riffat","doi":"10.1016/j.enconman.2026.121342","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121342","url":null,"abstract":"In the last decade, low-grade thermochemical energy storage systems have been gaining interest due to their long-term heat storage potential and high energy storage density. Despite the advantageous aspects of this heat storage method, previously investigated fixed-bed reactors suffer from low heat and mass transfer performance and offer limited process control. In order to overcome these challenges, a new multi-layer moving bed reactor was designed, manufactured, and tested in this study. The proposed reactor consists of reaction and storage sections where eight independent sorption beds have freedom of movement between the two sections. Such a design enables a modular concept, where each sorption bed could be charged or discharged individually, while the remaining sorption beds are stored inside their own hermetically insulated chambers. In the system, two different sizes of pumice stones, namely PM1 and PM2, were used as the host matrix, and three different thermochemical materials were synthesized by impregnation of the LiCl-CaCl<ce:inf loc=\"post\">2</ce:inf> mixture and CaCl<ce:inf loc=\"post\">2</ce:inf> as salts into pumice. During the experiments, comparative analyses of different materials, short-cycle full-system analyses, long-cycle energy density analyses, and multi-bed performance analyses have been performed. Additionally, the impact of air velocity was investigated. The evaluations were performed based on the First and Second Laws of Thermodynamics. Study results demonstrated that each sorption bed provides an average heat output between 0.58 and 1.07 kW depending on the inlet air conditions and the composition of thermochemical material. According to the study results, the energy storage density of the system was obtained as 189.7 kWh/m<ce:sup loc=\"post\">3</ce:sup> with the use of PM2-CaCl<ce:inf loc=\"post\">2</ce:inf>. On the other hand, 4.2 m/s was found as the most optimal air velocity, proving the highest average heat output during the discharging process and the highest moisture desorption rate per unit of heat consumed during the charging process. A linear correlation between the air absolute humidity difference and the air temperature lift for the discharging process was also obtained, which could provide useful insights for the performance prediction of thermochemical energy storage systems.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"17 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigates the economic feasibility and profitability of large-scale biomethane production through anaerobic digestion (AD) at plant capacities of 10, 20, and 40 GWh, using grass silage and cattle slurry as feedstocks. A robust deterministic and probabilistic modelling approach was employed to evaluate essential financial indicators, including Levelized Cost of Biomethane (LCOB), Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PBP). Sensitivity analysis observed at changes in the costs of grass silage (±30%) and biomethane (±50%). A Monte Carlo simulation with 10,000 iterations assessed at uncertainty by figuring out mean values, the chance of a positive NPV, and Conditional Value at Risk (CVaR). The results show that there is a good link between scale and financial performance. The cost of capital expenditures (CAPEX) ranged from €2.9 million for 10 GWh to €7.9 million for 40 GWh. As the scale of the plant grew, the cost of modifications and grid connections went down. The 40 GWh AD plant exhibited the strongest performance, achieving an NPV of approximately €22.2 million, an IRR of 30%, an LCOB of 0.079 €/kWh (≈ €0.79/Nm3), and a payback period of 3.2 years, whereas the 10 GWh plant delivered a lower IRR of 16% and a longer payback period of 6.7 years. A probabilistic investigation confirmed that larger investments are more resilient, with the probability of a positive NPV rising from 81% to 92%.
{"title":"Probabilistic techno-economic assessment of large-scale anaerobic digestion plants for biomethane production: de-risking biomethane futures","authors":"Shivali Sahota, Cathal Geoghegan, Cathal O’Donoghue","doi":"10.1016/j.enconman.2026.121316","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121316","url":null,"abstract":"This study investigates the economic feasibility and profitability of large-scale biomethane production through anaerobic digestion (AD) at plant capacities of 10, 20, and 40 GWh, using grass silage and cattle slurry as feedstocks. A robust deterministic and probabilistic modelling approach was employed to evaluate essential financial indicators, including Levelized Cost of Biomethane (LCOB), Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PBP). Sensitivity analysis observed at changes in the costs of grass silage (±30%) and biomethane (±50%). A Monte Carlo simulation with 10,000 iterations assessed at uncertainty by figuring out mean values, the chance of a positive NPV, and Conditional Value at Risk (CVaR). The results show that there is a good link between scale and financial performance. The cost of capital expenditures (CAPEX) ranged from €2.9 million for 10 GWh to €7.9 million for 40 GWh. As the scale of the plant grew, the cost of modifications and grid connections went down. The 40 GWh AD plant exhibited the strongest performance, achieving an NPV of approximately €22.2 million, an IRR of 30%, an LCOB of 0.079 €/kWh (≈ €0.79/Nm<ce:sup loc=\"post\">3</ce:sup>), and a payback period of 3.2 years, whereas the 10 GWh plant delivered a lower IRR of 16% and a longer payback period of 6.7 years. A probabilistic investigation confirmed that larger investments are more resilient, with the probability of a positive NPV rising from 81% to 92%.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"114 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-17DOI: 10.1016/j.enconman.2026.121366
Ali Khadir, Eunkyung Jang, Domenico Santoro, Ahmed Al-Omari, Christopher Muller, Katherine Y. Bell, Wayne Parker, Elsayed Elbeshbishy, George Nakhla
This study compares integrated thermal hydrolysis-anaerobic digestion (THP-AD) with the IntensiCarbTM (IC) vacuum-enhanced AD (IC-AD) of mixed primary and secondary sludges under identical organic loading rates (OLR) of 8–8.7 kgCOD/m3·d and solids retention times (SRT) of 18–20 d. IC-AD achieved a stable methane yield of 0.22 L-CH4/gCODfed (55% COD destruction), while THP-AD produced < 0.1 L-CH4/gCODfed and failed due to the toxicity of high ammonia (>3.3 gN/L) and propionate (>2.8 g/L) accumulation when using both acclimatized and unacclimatized THP biomass. The IC-AD reduced digester ammonia by 49%-56% via ex-situ vacuum application whereas in THP-AD, ammonia accumulated. Off-line batch tests showed acetate, butyrate and propionate degradation rates were 2.3–2.7 times higher in IC-AD than THP-AD. Ammonia inhibition batch tests showed methane production rate reductions of 27% in IC and 58% in THP at 2–4 g-ammonia/L, highlighting the higher inhibition threshold of the IC biomass. The microbial communities showed distinct differences: IC-AD was dominated by Firmicutes with enriched Petrimonas and Syntrophomonas, while THP-AD was dominated by Bacteroidota with enriched Corynebacterium and Syntrophomonas. Methanogen counts were 6.2 times higher in the IC-AD due to the presence of high-growth-rate acetoclastic Methanosarcinaceae while hydrogenotrophic Methanobacteriaceae were the most abundant methanogen in the THP-AD. In offline tests with acetate, the biomass-specific methane production rate in the IC-AD was 8.4 times higher, suggesting that the acetoclastic pathway associated with Methanosarcinaceae provided superior process performance to the hydrogenotrophic Methanobacteriaceae pathway. Overall, when operated at similar loadings IC-AD outperformed THP-AD, achieving stable methane production and enriched beneficial microbial communities while also recovering ammonia as an additional value-added product.
{"title":"Enhanced methane production and ammonia inhibition mitigation in intensified anaerobic digestion of high nitrogen biosolids: ex-situ vacuum stripping versus thermal hydrolysis","authors":"Ali Khadir, Eunkyung Jang, Domenico Santoro, Ahmed Al-Omari, Christopher Muller, Katherine Y. Bell, Wayne Parker, Elsayed Elbeshbishy, George Nakhla","doi":"10.1016/j.enconman.2026.121366","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121366","url":null,"abstract":"This study compares integrated thermal hydrolysis-anaerobic digestion (THP-AD) with the IntensiCarb<ce:sup loc=\"post\">TM</ce:sup> (IC) vacuum-enhanced AD (IC-AD) of mixed primary and secondary sludges under identical organic loading rates (OLR) of 8–8.7 kgCOD/m<ce:sup loc=\"post\">3</ce:sup>·d and solids retention times (SRT) of 18–20 d. IC-AD achieved a stable methane yield of 0.22 L-CH<ce:inf loc=\"post\">4</ce:inf>/gCOD<ce:inf loc=\"post\">fed</ce:inf> (55% COD destruction), while THP-AD produced < 0.1 L-CH<ce:inf loc=\"post\">4</ce:inf>/gCOD<ce:inf loc=\"post\">fed</ce:inf> and failed due to the toxicity of high ammonia (>3.3 gN/L) and propionate (>2.8 g/L) accumulation when using both acclimatized and unacclimatized THP biomass. The IC-AD reduced digester ammonia by 49%-56% via ex-situ vacuum application whereas in THP-AD, ammonia accumulated. Off-line batch tests showed acetate, butyrate and propionate degradation rates were 2.3–2.7 times higher in IC-AD than THP-AD. Ammonia inhibition batch tests showed methane production rate reductions of 27% in IC and 58% in THP at 2–4 g-ammonia/L, highlighting the higher inhibition threshold of the IC biomass. The microbial communities showed distinct differences: IC-AD was dominated by <ce:italic>Firmicutes</ce:italic> with enriched <ce:italic>Petrimonas</ce:italic> and <ce:italic>Syntrophomonas</ce:italic>, while THP-AD was dominated by <ce:italic>Bacteroidota</ce:italic> with enriched <ce:italic>Corynebacterium</ce:italic> and <ce:italic>Syntrophomonas</ce:italic>. Methanogen counts were 6.2 times higher in the IC-AD due to the presence of high-growth-rate acetoclastic <ce:italic>Methanosarcinaceae</ce:italic> while hydrogenotrophic <ce:italic>Methanobacteriaceae</ce:italic> were the most abundant methanogen in the THP-AD. In offline tests with acetate, the biomass-specific methane production rate in the IC-AD was 8.4 times higher, suggesting that the acetoclastic pathway associated with <ce:italic>Methanosarcinaceae</ce:italic> provided superior process performance to the hydrogenotrophic <ce:italic>Methanobacteriaceae</ce:italic> pathway. Overall, when operated at similar loadings IC-AD outperformed THP-AD, achieving stable methane production and enriched beneficial microbial communities while also recovering ammonia as an additional value-added product.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"87 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This manuscript presents a techno-economic assessment of a waste-to-energy-based tri-generation energy system using an integrated energy, exergy, and economic (3E) framework. This is a particularly crucial approach for waste-to-energy incineration power plants, where exergy destruction in the components, especially in the incinerator, hinders their development and practical application. A systematic strategy based on sensitivity analysis has been suggested and adopted in this manuscript through a case study, using a multi-objective optimization tool to preserve the economic viability of waste-to-energy incineration power plants while maintaining their exergy efficiency at its maximum level. The MSW cost rate was chosen as the key input parameter for conducting the sensitivity analysis and thus take into account the uncertainties. A hybrid thermodynamic approach combining finite-time thermodynamics (FTT) and conventional irreversible thermodynamics has been designed to jointly model an innovative multigenerational energy system based on waste-to-energy (W-to-E) incineration technology. The combined-cycle power plant integrates a single-effect Heating, Ventilation, Air Conditioning and Absorption Refrigeration (HVAC-AR) system powered by a Latent Heat Thermal Energy Storage (LHTES) system capable of simultaneously providing electricity, heating, and cooling. The FTT is formulated as a Linear Programming Problem (LPP) to optimally allocate HVAC-AR thermal conductance, while the overall system is optimized using an Evolutionary Multi-Objective Optimization (EMOO) algorithm to explore the trade-off between exergy efficiency and total product cost. A case study, conducted under typical conditions in southern Brazil, shows that the system achieves an exergy efficiency of 13.27% and a total production cost of $13.82/h. The optimization procedure identifies operating conditions that increase exergy efficiency by 3.18% and electricity production by 6%, while adjusting component-level cost contributions. Sensitivity analysis indicates an upper MSW price limit of $41/ton for the multi-generation energy system to remain cost-competitive with local electricity tariffs.
{"title":"Techno-economic analysis based on energy, exergy and economic (3E) assessment and multi-objective optimization of multi generation energy system: case study of a tri-generation power plant with LHTES integrated using W-to-E incineration technology","authors":"A.F.I. Mamadou, M.O.K. Idrissou, B.R. Sanoussi, J.V.C. Vargas","doi":"10.1016/j.enconman.2026.121290","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121290","url":null,"abstract":"This manuscript presents a techno-economic assessment of a waste-to-energy-based tri-generation energy system using an integrated energy, exergy, and economic (3E) framework. This is a particularly crucial approach for waste-to-energy incineration power plants, where exergy destruction in the components, especially in the incinerator, hinders their development and practical application. A systematic strategy based on sensitivity analysis has been suggested and adopted in this manuscript through a case study, using a multi-objective optimization tool to preserve the economic viability of waste-to-energy incineration power plants while maintaining their exergy efficiency at its maximum level. The MSW cost rate was chosen as the key input parameter for conducting the sensitivity analysis and thus take into account the uncertainties. A hybrid thermodynamic approach combining finite-time thermodynamics (FTT) and conventional irreversible thermodynamics has been designed to jointly model an innovative multigenerational energy system based on waste-to-energy (W-to-E) incineration technology. The combined-cycle power plant integrates a single-effect Heating, Ventilation, Air Conditioning and Absorption Refrigeration (HVAC-AR) system powered by a Latent Heat Thermal Energy Storage (LHTES) system capable of simultaneously providing electricity, heating, and cooling. The FTT is formulated as a Linear Programming Problem (LPP) to optimally allocate HVAC-AR thermal conductance, while the overall system is optimized using an Evolutionary Multi-Objective Optimization (EMOO) algorithm to explore the trade-off between exergy efficiency and total product cost. A case study, conducted under typical conditions in southern Brazil, shows that the system achieves an exergy efficiency of 13.27% and a total production cost of $13.82/h. The optimization procedure identifies operating conditions that increase exergy efficiency by 3.18% and electricity production by 6%, while adjusting component-level cost contributions. Sensitivity analysis indicates an upper MSW price limit of $41/ton for the multi-generation energy system to remain cost-competitive with local electricity tariffs.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"57 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-16DOI: 10.1016/j.enconman.2026.121319
Marcus Ringström, Henrik Ekström, Lisa Kylhammar, Göran Lindbergh, Rakel Wreland Lindström
The mechanical properties of gas diffusion layers (GDLs) in proton exchange membrane fuel cells (PEMFCs critically govern compression-dependent transport phenomena that control local performance and durability. This work presents a systematic, self-consistent characterization of orthotropic mechanical behavior, through-plane (TP) thermal and electrical conductivities, in-plane (IP) gas permeability, and structural properties for five commercial GDLs—wet-laid carbon papers (Toray TGP-H-060 with 5 and 30 wt% PTFE; SGL 29BA uncoated; SGL 28BC MPL-coated) and one hydroentangled non-woven (Freudenberg H23C7)—measured under controlled compressive loads (0.5–3 MPa). Additional GDL materials are benchmarked against literature data.
{"title":"Comprehensive ex-situ characterization of the compression-dependent properties of gas diffusion layers in PEM fuel cells","authors":"Marcus Ringström, Henrik Ekström, Lisa Kylhammar, Göran Lindbergh, Rakel Wreland Lindström","doi":"10.1016/j.enconman.2026.121319","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121319","url":null,"abstract":"The mechanical properties of gas diffusion layers (GDLs) in proton exchange membrane fuel cells (PEMFCs critically govern compression-dependent transport phenomena that control local performance and durability. This work presents a systematic, self-consistent characterization of orthotropic mechanical behavior, through-plane (TP) thermal and electrical conductivities, in-plane (IP) gas permeability, and structural properties for five commercial GDLs—wet-laid carbon papers (Toray TGP-H-060 with 5 and 30 wt% PTFE; SGL 29BA uncoated; SGL 28BC MPL-coated) and one hydroentangled non-woven (Freudenberg H23C7)—measured under controlled compressive loads (0.5–3 MPa). Additional GDL materials are benchmarked against literature data.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"94 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147464768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-16DOI: 10.1016/j.enconman.2026.121363
Seok Jun Moon, Hokyu Moon, Namil Her, Kyoung-O Kang, Namkyu Lee
For fusion power plants like Korean Demonstration Power Plant (K-DEMO) to contribute to carbon neutrality, achieving sufficient net electricity generation is essential. This goal is challenged by the thermal limitations of current structural materials, which constrain the helium blanket coolant outlet temperature to approximately 500 ℃, and by large auxiliary power demands. This means that if the temperature limit is broken, a higher operating temperature will be possible to enhance the thermal efficiency of balance of plant for energy conversion. For this reason, a necessary strategy requires a data-driven comparison of the primary power conversion system candidates for the nuclear fusion power plant at the conceptual design stage, such as the steam Rankine and helium Brayton cycles, above 500 ℃. This study conducts a comprehensive thermodynamic analysis to provide data-driven design guidance for the K-DEMO balance of plant for energy conversion as a function of blanket outlet temperature. Steady-state models of each cycle coupled to a helium-cooled primary heat transfer system were developed and validated against reference plant data. The results confirm the Rankine cycle’s thermodynamic superiority at the current K-DEMO reference temperature. The Brayton cycle’s efficiency markedly increases with temperature, although it only exceeds the baseline Rankine system at moderate temperatures and the high-performance advanced ultra-supercritical Rankine cycle at considerably higher temperatures. These findings establish the Rankine cycle as the more advantageous option for near-term designs, positioning the Brayton cycle as a long-term alternative that is contingent on significant advancements in high-temperature materials.
{"title":"Conceptual comparison of Rankine and helium Brayton cycles for future Korean DEMO fusion power plant","authors":"Seok Jun Moon, Hokyu Moon, Namil Her, Kyoung-O Kang, Namkyu Lee","doi":"10.1016/j.enconman.2026.121363","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121363","url":null,"abstract":"For fusion power plants like Korean Demonstration Power Plant (K-DEMO) to contribute to carbon neutrality, achieving sufficient net electricity generation is essential. This goal is challenged by the thermal limitations of current structural materials, which constrain the helium blanket coolant outlet temperature to approximately 500 ℃, and by large auxiliary power demands. This means that if the temperature limit is broken, a higher operating temperature will be possible to enhance the thermal efficiency of balance of plant for energy conversion. For this reason, a necessary strategy requires a data-driven comparison of the primary power conversion system candidates for the nuclear fusion power plant at the conceptual design stage, such as the steam Rankine and helium Brayton cycles, above 500 ℃. This study conducts a comprehensive thermodynamic analysis to provide data-driven design guidance for the K-DEMO balance of plant for energy conversion as a function of blanket outlet temperature. Steady-state models of each cycle coupled to a helium-cooled primary heat transfer system were developed and validated against reference plant data. The results confirm the Rankine cycle’s thermodynamic superiority at the current K-DEMO reference temperature. The Brayton cycle’s efficiency markedly increases with temperature, although it only exceeds the baseline Rankine system at moderate temperatures and the high-performance advanced ultra-supercritical Rankine cycle at considerably higher temperatures. These findings establish the Rankine cycle as the more advantageous option for near-term designs, positioning the Brayton cycle as a long-term alternative that is contingent on significant advancements in high-temperature materials.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"10 11 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147464765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-16DOI: 10.1016/j.enconman.2026.121147
Saeid Hassankhani Dolatabadi, Haris Ishaq, Curran Crawford
The maritime sector is under mounting pressure to decarbonize, with international shipping responsible for nearly 3% of global greenhouse gas (GHG) emissions. However, the industry faces substantial uncertainty regarding viable next-generation marine fuel pathways, and existing studies largely lack scenario-based assessments that reflect divergent policy and market priorities. In this context, this study applies a multi-criteria decision analysis (MCDA), operationalized through the TOPSIS method, across 19 decision attributes grouped into four categories (environmental, economic, technical readiness, and operability) under three policy-relevant scenarios: balanced, climate-led, and cost-led. The framework evaluates energy transition pathways for international shipping aligned with mid-century climate goals, focusing on leading alternative fuels (ammonia, methanol, hydrogen, and biodiesel). Fuel performance and attributes importance assumptions for the 2050 horizon are synthesized from a broad range of academic and industry sources and assessed within the defined scenarios. Ranking outcomes are further examined using Monte Carlo (MC) simulations that explicitly distinguish uncertainty in future fuel performance from uncertainty in policy and stakeholder priorities. The results show that fuel rankings are highly sensitive to both scenario framing and uncertainty structure, with no single fuel consistently dominating across perspectives. Hydrogen performs best under climate-led priorities, biodiesel dominates under cost-led conditions, and ammonia and methanol emerge as competitive options under balanced scenarios. The TOPSIS results reveal clear rank reversals across scenarios. In the balanced scenario, ammonia ranks first, followed by methanol and hydrogen, with biodiesel ranking last. Under the climate-led scenario, hydrogen emerges as the top-ranked fuel, followed by ammonia and methanol, while biodiesel consistently ranks lowest. In contrast, the cost-led scenario favors biodiesel as the leading option, followed by ammonia and methanol, with hydrogen ranking last. MC sensitivity analyses indicate that these rankings are robust but not deterministic. Rankings are relatively stable under weight-only uncertainty, more sensitive to uncertainty in fuel performance scores, and most variable when uncertainty in both scores and weights is combined. Category-level uncertainty analysis further shows that economic and operability attributes exert the greatest influence on ranking outcomes, while technical readiness and environmental attributes play a more limited role in differentiating fuels at the 2050 horizon.
{"title":"Scenario-based multi-criteria evaluation of alternative fuels for international marine transportation","authors":"Saeid Hassankhani Dolatabadi, Haris Ishaq, Curran Crawford","doi":"10.1016/j.enconman.2026.121147","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121147","url":null,"abstract":"The maritime sector is under mounting pressure to decarbonize, with international shipping responsible for nearly 3% of global greenhouse gas (GHG) emissions. However, the industry faces substantial uncertainty regarding viable next-generation marine fuel pathways, and existing studies largely lack scenario-based assessments that reflect divergent policy and market priorities. In this context, this study applies a multi-criteria decision analysis (MCDA), operationalized through the TOPSIS method, across 19 decision attributes grouped into four categories (environmental, economic, technical readiness, and operability) under three policy-relevant scenarios: balanced, climate-led, and cost-led. The framework evaluates energy transition pathways for international shipping aligned with mid-century climate goals, focusing on leading alternative fuels (ammonia, methanol, hydrogen, and biodiesel). Fuel performance and attributes importance assumptions for the 2050 horizon are synthesized from a broad range of academic and industry sources and assessed within the defined scenarios. Ranking outcomes are further examined using Monte Carlo (MC) simulations that explicitly distinguish uncertainty in future fuel performance from uncertainty in policy and stakeholder priorities. The results show that fuel rankings are highly sensitive to both scenario framing and uncertainty structure, with no single fuel consistently dominating across perspectives. Hydrogen performs best under climate-led priorities, biodiesel dominates under cost-led conditions, and ammonia and methanol emerge as competitive options under balanced scenarios. The TOPSIS results reveal clear rank reversals across scenarios. In the balanced scenario, ammonia ranks first, followed by methanol and hydrogen, with biodiesel ranking last. Under the climate-led scenario, hydrogen emerges as the top-ranked fuel, followed by ammonia and methanol, while biodiesel consistently ranks lowest. In contrast, the cost-led scenario favors biodiesel as the leading option, followed by ammonia and methanol, with hydrogen ranking last. MC sensitivity analyses indicate that these rankings are robust but not deterministic. Rankings are relatively stable under weight-only uncertainty, more sensitive to uncertainty in fuel performance scores, and most variable when uncertainty in both scores and weights is combined. Category-level uncertainty analysis further shows that economic and operability attributes exert the greatest influence on ranking outcomes, while technical readiness and environmental attributes play a more limited role in differentiating fuels at the 2050 horizon.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"212 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-16DOI: 10.1016/j.enconman.2026.121360
Evangelos Bellos
High-temperature heat pumps (HTHPs) are high-potential technologies for the decarbonization of low- and medium-temperature industrial heating processes. The conventional HTHPs can deliver heat up to 150-160°C, while the process heat production at higher temperatures is a challenge that has attracted a lot of research in the last year. The goal of this work is to conduct a detailed investigation of different configurations of supercritical CO2 reverse Brayton HTHPs, aiming to determine the most efficient and promising designs. This analysis investigates different process heat production from 150°C up to 250°C, while the HTHPs are driven by low-grade waste heat in the range of 50–120°C. This work is performed with developed mathematical thermodynamic models in Engineering Equation Solver, which are verified with literature data. According to the results of this analysis, the recompression is a proper solution for low heating production temperatures (mainly at 150°C), while at higher heating production temperatures, the Reheating with an internal heat exchanger has to be selected. The application of the internal heat exchanger enhances the coefficient of performance up to 8.13% and the exergy efficiency up to 6.54%. For the typical case with source temperature at 100°C, the average COP enhancement is found at 3.9% with internal heat exchanger, at 12.5% with Reheating with internal heat exchanger and at 15.5% with Double reheating with internal heat exchanger compared to the Simple cycle.
{"title":"A comparative thermodynamic analysis of different supercritical CO2 reverse Brayton high temperature heat pumps","authors":"Evangelos Bellos","doi":"10.1016/j.enconman.2026.121360","DOIUrl":"https://doi.org/10.1016/j.enconman.2026.121360","url":null,"abstract":"High-temperature heat pumps (HTHPs) are high-potential technologies for the decarbonization of low- and medium-temperature industrial heating processes. The conventional HTHPs can deliver heat up to 150-160<ce:hsp sp=\"0.25\"></ce:hsp>°C, while the process heat production at higher temperatures is a challenge that has attracted a lot of research in the last year. The goal of this work is to conduct a detailed investigation of different configurations of supercritical CO<ce:inf loc=\"post\">2</ce:inf> reverse Brayton HTHPs, aiming to determine the most efficient and promising designs. This analysis investigates different process heat production from 150<ce:hsp sp=\"0.25\"></ce:hsp>°C up to 250<ce:hsp sp=\"0.25\"></ce:hsp>°C, while the HTHPs are driven by low-grade waste heat in the range of 50<ce:hsp sp=\"0.25\"></ce:hsp>–120<ce:hsp sp=\"0.25\"></ce:hsp>°C. This work is performed with developed mathematical thermodynamic models in Engineering Equation Solver, which are verified with literature data. According to the results of this analysis, the recompression is a proper solution for low heating production temperatures (mainly at 150<ce:hsp sp=\"0.25\"></ce:hsp>°C), while at higher heating production temperatures, the Reheating with an internal heat exchanger has to be selected. The application of the internal heat exchanger enhances the coefficient of performance up to 8.13% and the exergy efficiency up to 6.54%. For the typical case with source temperature at 100<ce:hsp sp=\"0.25\"></ce:hsp>°C, the average COP enhancement is found at 3.9% with internal heat exchanger, at 12.5% with Reheating with internal heat exchanger and at 15.5% with Double reheating with internal heat exchanger compared to the Simple cycle.","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"39 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147464766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：