ASME 2018 12th International Conference on Energy Sustainability最新文献

{"title":"A Dynamic Model Incorporating the Effects of the Ion Diffusion and Side Reactions for the Vanadium/Air Redox Flow Battery","authors":"Yu Shi, Jiyun Zhao","doi":"10.1115/ES2018-7120","DOIUrl":"https://doi.org/10.1115/ES2018-7120","url":null,"abstract":"The vanadium/air redox flow battery working performance will be affected by many factors, including the quality of the membrane used and the working conditions. The crossover rate of vanadium ions for the membrane can determine the capacity due to the ion diffusion and the side reactions. The high reaction temperature for the VARFB also influence the diffusion coefficient. Based on Fick’s Law, by using Arrhenius Equation to predict the temperature effect, and take into consider that the mass balance for each reacting ions and reaction temperature, the dynamic modelling on capacity decay can be developed. Then by using Nernst Equation, the voltage change of VARFB can also be calculated. This dynamic model will predict the concentration change of the battery as a function of time, after benchmarking with the experimental data, this model can compare the performance of the battery with a different order of diffusion coefficient membranes in different working condition. This model can also predict the contacting V2+ concentration to the electrode and catalyst to monitor the working efficiency.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130279435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Parasitic Absorption in Back Contact of CdTe Solar Cells","authors":"Joshua Smay, Ola Rashwan, James Then, Darien Perez","doi":"10.1115/ES2018-7533","DOIUrl":"https://doi.org/10.1115/ES2018-7533","url":null,"abstract":"Thin film solar cells (TFSC) differ from the conventional wafer solar cell panels in that they are a fraction of the thickness, hence they boast reduced material costs, lighter weight, and possible flexibility. To improve their light-trapping and absorption efficiency, manufacturers currently use nanometer scale texturing. When manufacturing nano textured thin film solar cells in the substrate configuration, the back reflector is also textured. It has been observed that a textured back reflector leads to parasitic light absorption in silicon solar cells. This occurrence reduces the back reflector effectiveness, and thus reduces absorption in the absorber layer and overall efficiency. However, there is little to no similar research done for thin film (CdTe/CdS) solar cells devices. In this work, wave optical analyses of thin film CdTe/CdS solar cells with and without nano texturing on the metal back reflectors were simulated using ANSYS ANSOFT High Frequency Structural Simulator (HFSS). The optical analyses yielded percentage absorptions for unit cells with four absorber thicknesses range between 250- to 1000 nm, with and without a textured back reflector over six wavelengths range from 360nm to 860 nm, and with 3 different back contact metals (Au, Ag, and Al). It was noted that the textured back contacts show a substantial increase in the absorption in the active CdTe layer in the infrared range. Additionally, back reflector texturing increases the parasitic absorption in the metal back reflector layer as well, especially with ultrathin absorber layer. It was also found that additional parasitic absorption due to a textured back reflector has less of an impact on absorption as the active absorber thickness increases to 500 nm, 750 nm, or 1000 nm. Finally, silver (Ag) as back contact outperforms both aluminum (Al) and gold (Au). This finding might be crucial to solar cell manufacturers because it could possibly be an overlooked factor in achieving higher efficiencies for relatively thin cells.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126242185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Potential for Integrating Solar Thermal Energy in Both Centralized and Decentralized Systems in Egypt","authors":"R. Imam, M. Yassin","doi":"10.1115/ES2018-7465","DOIUrl":"https://doi.org/10.1115/ES2018-7465","url":null,"abstract":"There is an increasing need for the integration of renewable energy into the energy sector in Egypt. As the electricity subsidies are residing for consumers in Egypt, electricity prices are increasing. This increase in energy prices can be mitigated by the integration of renewable energy technologies. One of the most promising renewable energy technologies that will help stabilize the energy situation in Egypt, is Solar Thermal Energy. Solar Thermal Energy has a great potential in Egypt due to the availability and intensity of direct irradiance in Egypt. Therefore, Egypt has an amazing opportunity as a developing country to start perusing solar thermal technologies; these technologies include decentralized and centralized technologies. Decentralized technologies are targeted more for regular consumers and centralized technologies are targeted more for power generation and industries.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128856147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of Hydro-Turbines in Wastewater Treatment Plants (WWTPs)","authors":"Ahmad I. Abbas, M. Qandil, M. Al-Haddad, Mandana S. Saravani, R. Amano","doi":"10.1115/ES2018-7349","DOIUrl":"https://doi.org/10.1115/ES2018-7349","url":null,"abstract":"Wastewater treatment plants (WWTPs) are a significant energy consumer, yet there are several opportunities of implementing on-site power generation systems. Within the treatment process, the high flow rate of effluent is produced and discharged to a nearby water body by gravity. Thus, hydro turbines can be utilized to generate power in such application due to a difference in elevation and high flow rate. This paper presents a case study of introducing a hydro turbine in wastewater treatment plant in Wisconsin and evaluating the power output in addition to determining the energy savings. The wastewater treatment plant considered in this study has an effluent flow rate of 190 MGD (million gallons per day) and elevation difference of 3 meters (10 feet) between the final stage of treatment and the discharge point. Based on the aforementioned parameters; hubless rim-drive Kaplan type hydro turbine (RDT) is the optimal choice to be used in such application. The RDT is designed and optimized by using in-house code. A computational fluid dynamics (CFD) software is applied to evaluate the performance of the proposed model, and the system is simulated through HOMER software to validate the results generated by the CFD. The expected savings is estimated to be 1,564 MWh/year.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134100445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parametric Experiments of Water Transport Characteristic in Nafion® Membrane","authors":"Jaemin Son, Sangseok Yu","doi":"10.1115/ES2018-7304","DOIUrl":"https://doi.org/10.1115/ES2018-7304","url":null,"abstract":"In a PEMFC (Proton electrolyte membrane fuel cell), water transport mechanism inside the membrane is very important in performance and durability of whole fuel cell stack. Diffusion of water through the membrane is governed by humidity conditions of outer layers and the humidity conditions of gases depend on temperature, pressure and operating pressures. Since those parameters are varied non-linearly, it is necessary to investigate water transport mechanism by concentration difference between both sides of membrane.\u0000 In this study, water contents of Nafion® membrane is measured in terms of relative humidity, temperatures, and operating pressure. Water diffusion is also measured at different pressures in both sides. Test chamber is designed to fix membrane in the middle of chamber and the membrane separates chambers in two spaces. Parametric study is conducted to measure the water contents of membranes in terms of temperatures 30°C, 50°C, 70°C, 90°C and 0 to 100% relative humidity. When the water diffusivity is calculated by measured data, the water concentrations in both sides are determined by harmonic averages of inlet and exit water humidity. Additionally, water flux is also investigated in terms of both sides humidity, operating pressure and temperatures. As a result, the water diffusion coefficient was explained by the operating temperature and the relative humidity and operating pressures.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"202 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132967293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Novel Solar Photoelectrochemical Tandem Reactor With a Perforated Photocathode for Simultaneous Hydrogen Production and Waste Water Treatment","authors":"Michael Wullenkord, C. Jung, O. Smirnova, C. Sattler","doi":"10.1115/ES2018-7187","DOIUrl":"https://doi.org/10.1115/ES2018-7187","url":null,"abstract":"Hydrogen generation in solar photoelectrochemical reactors could provide an important contribution to future energy regimes by storing intermittent renewable energy in a versatile energy vector. Using waste water as electron donor potentially facilitates economic operation. Here, organic contaminants instead of water are oxidised at the anode and two products of value are obtained simultaneously: hydrogen and clean water. Three different reactor concepts were compared in terms of ohmic losses. Based on the results of the simplified analysis a novel planar and scalable solar reactor with an aperture area of 368 cm2 was developed. It features a perforated photocathode and a non-perforated photoanode, both cold gas sprayed, in tandem arrangement and accepts electrolyte temperatures of up to 80°C. Confirmed by ray-tracing simulations the slit design of the photocathode allows homogeneous illumination of the two involved photoelectrodes with DLR’s test platform SoCRatus (Solar Concentrator with a Rectangular Flat Focus). The photocathode compartment and the photoanode compartment are separated by a membrane. Thus, the membrane being located in the optical path has to show sufficiently high transparency for solar light, particularly in the UV-Vis range. A 1,418 h aging study was performed in order to assess the optical performance of a Nafion™ membrane N1110 exposed to an aqueous mixture at 80°C, which contained 10 vol.-% methanol as a model substance for organic contaminants and sulfuric acid to adjust pH 3. It could be verified that the membrane maintains high transparency in the considered wavelength region from 280 nm to 1,100 nm which suggests the feasibility of the reactor concept. The design electrolyte flow of 2.5 l/min through each of the two reactor chambers practically allows isothermal operation on the SoCRatus under 17.5-fold concentrated irradiation. The inlet and outlet geometry of the reactor aims at uniform flow patterns, a low pressure drop as well as effective product gas transport and was optimised for automatic manufacturing. Reference electrodes and temperature sensors are incorporated directly in the reactor body for extended analysis and operation options. The parts of the reactor ensure compatibility with a wide range of waste waters and involved chemicals as well as mechanical stability. Moreover, they are resistant to light exposure and weathering.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123520110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Simple EAM Potential for Hydrogen-Selective Palladium Based Membranes for Biomass Derived Syngas Processing","authors":"I. Hijazi, Yang Zhang, Robert Fuller","doi":"10.1115/ES2018-7369","DOIUrl":"https://doi.org/10.1115/ES2018-7369","url":null,"abstract":"Biomass offers the potential to economically produce hydrogen via gasification from an abundant and renewable feedstock. When hydrogen is produced from a biomass gasifier, it is necessary to purify it from syngas streams containing components such as CO, CO2, N2, CH4, and other products. Therefore, a challenge related to hydrogen purification is the development of hydrogen-selective membranes that can operate at elevated temperatures and pressures, provide high fluxes, long operational lifetime, and resistance to poisoning while still maintaining reasonable cost. Palladium based membranes have been shown to be well suited for these types of high-temperature applications and have been widely utilized for hydrogen separation. Palladium’s unique ability to absorb a large quantity of hydrogen can also be applied in various clean energy technologies, like hydrogen fuel cells. In this paper, a fully analytical interatomic Embedded Atom Potential (EAM) for the Pd-H system has been developed, that is easily extendable to ternary Palladium based hydride systems such as Pd-Cu-H and Pd-Ag-H. The new potential has fewer fitting parameters than previously developed EAM Pd-H potentials and is able to accurately predict the cohesive energy, lattice constant, bulk modulus, elastic constants, melting temperature, and the stable Pd-H structures in molecular dynamics (MD) simulations with various hydrogen concentrations. The EAM potential also well predicts the miscibility gap, the segregation of the palladium hydride system into dilute (α) and concentrated (β) phases.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115722763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EnergyPlus Integration Into Co-Simulation Environment to Improve Home Energy Saving Through Cyber-Physical Systems Development","authors":"J. Singer, Thomas P. Roth, Chenli Wang, Cuong Nguyen, Hohyun Lee","doi":"10.1115/ES2018-7295","DOIUrl":"https://doi.org/10.1115/ES2018-7295","url":null,"abstract":"This paper presents a co-simulation platform which combines a building simulation tool with a Cyber-Physical Systems (CPS) approach. Residential buildings have a great potential of energy reduction by controlling home equipment based on usage information. A CPS can eliminate unnecessary energy usage on a small, local scale by autonomously optimizing equipment activity, based on sensor measurements from the home. It can also allow peak shaving from the grid if a collection of homes are connected. However, lack of verification tools limits effective development of CPS products. The present work integrates EnergyPlus, which is a widely adopted building simulation tool, into an open-source development environment for CPS released by the National Institute of Standards and Technology (NIST). The NIST environment utilizes the IEEE High Level Architecture (HLA) standard for data exchange and logical timing control to integrate a suite of simulators into a common platform. A simple CPS model, which controls local HVAC temperature set-point based on environmental conditions, was tested with the developed co-simulation platform. The proposed platform can be expanded to integrate various simulation tools and various home simulations, thereby allowing for co-simulation of more intricate building energy systems.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117059066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling, Development and Preliminary Testing of a 2 MW PEM Fuel Cell Plant Fueled With Hydrogen From a Chlor-Alkali Industry","authors":"S. Campanari, G. Guandalini, J. Coolegem, J. T. Have, P. Hayes, A. Pichel","doi":"10.1115/ES2018-7340","DOIUrl":"https://doi.org/10.1115/ES2018-7340","url":null,"abstract":"The chlor-alkali industry produces significant amounts of hydrogen as byproduct and an interesting benefit can be obtained by feeding hydrogen to a PEM fuel cell unit, whose electricity and heat production can cover part of the chemical plant consumptions. The estimated potential of such application is up to 1100 MWel installed in the sole China, a country featuring a large presence of chlor-alkali plants.\u0000 This work presents the modeling, development and first experimental results from field tests of a 2 MW PEM fuel cell power plant, built within the European project DEMCOPEM-2MW and installed in Yingkou, China as the current world’s largest PEM fuel cell installation. After a preliminary introduction to the market potential of PEM Fuel cells in the chlor-alkali industry, it is first discussed an overview of project’s MEA and fuel cell development for long life stationary applications, focusing on the design-for-manufacture process and the high-volume manufacturing route developed for the 2MW plant.\u0000 The work then discusses the modeling of the power plant, including a specific lumped model predicting FC stack behavior as a function of inlet streams conditions and power set point, according to regressed polarization curves. Cells performance decay vs. lifetime reflects long-term stack test data, aiming to evidence the impact on overall energy balances and efficiency of the progression of lifetime. BOP is modeled to simulate auxiliaries consumption, pressure drops and components operating conditions. The model allows studying different operational strategies that maintain the power production during lifetime, minimizing efficiency losses; as well as to investigate the optimized operating setpoint of the plant at full load and during part-load operation.\u0000 The last section of the paper discusses the experimental results, through a complete analysis of the plant performance after plant startup, including energy and mass balances and allowing to validate the model. Cumulated indicators over the first nine months of operations regarding energy production, hydrogen consumption and efficiency are also discussed.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125677699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biogas Potentials Evaluation of Household Wastes in Johannesburg Metropolitan Area Using the Automatic Methane Potential Test System (AMPTS) II","authors":"Prof Kevin N. Nwaigwe, A. Agarwal, E. E. Anyanwu","doi":"10.1115/ES2018-7553","DOIUrl":"https://doi.org/10.1115/ES2018-7553","url":null,"abstract":"A work on biogas potentials evaluation of household wastes in Johannesburg metropolitan area using the Automatic Methane Potential Test System (AMPTS) II is presented. The AMPTS II consists of three units — the sample incubation unit, CO2 absorption unit and the gas volume measuring device. Organic fraction of wastes collected from households within Johannesburg metropolis were sorted, ground and prepared into slurry by mixing with water. Microcrystalline cellulose powder with 3.5% loss on drying and 0.28g/cc density was used as control substrate while anaerobic sludge collected from a functional biogas reactor was used as inoculum. Anaerobic sludge was classified as sample A, household waste containing mainly non-food waste was labelled sample B, sample C was microcrystalline cellulose used as positive control while household waste composing of mainly food waste was classified as sample D. Each sample was fed into a 50 mL bottle reactor in triplicates and stirred in a clockwise direction continuously for 5 minutes with a pulse interval of 1 minute at a set temperature of 37°C for 30 days retention time. NaOH solution was prepared into solution following standard procedure and mixed with a prepared 0.4 % Thymolpthalein solution. The resultant solution was poured into the 100 mL bottles of the CO2 unit. Produced biogas was measured through water displacement in the volumetric bath and values read off through a data-logger connected to a laptop. Results indicated biochemical methane potential (BMP) of 69–800 NmL/gvs and biogas composition with more than 50% methane before CO2 fixing and over 80% after CO2 fixing. Given that the average amount of waste generated per person per day in South Africa is over 0.7 kg, there is huge potentials for biogas production from household wastes in Johannesburg.","PeriodicalId":298211,"journal":{"name":"ASME 2018 12th International Conference on Energy Sustainability","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131130575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}