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  • 1.
    Abbas, Ghazanfar
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ashfaq, M.
    Chaudhry, M. Ashraf
    Khan, Ajmal
    Ahmad, Imran
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Electrochemical study of nanostructured electrode for low-temperature solid oxide fuel cell (LTSOFC)2014In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 38, no 4, p. 518-523Article in journal (Refereed)
    Abstract [en]

    Zn-based nanostructured Ba0.05Cu0.25Fe0.10Zn0.60O (BCFZ) oxide electrode material was synthesized by solid-state reaction for low-temperature solid oxide fuel cell. The cell was fabricated by sandwiching NK-CDC electrolyte between BCFZ electrodes by dry press technique, and its performance was assessed. The maximum power density of 741.87 mW-cm(-2) was achieved at 550 degrees C. The crystal structure and morphology were characterized by X-ray diffractometer (XRD) and SEM. The particle size was calculated to be 25 nm applying Scherer's formula from XRD data. Electronic conductivities were measured with the four-probe DC method under hydrogen and air atmosphere. AC Electrochemical Impedance Spectroscopy of the BCFZ oxide electrode was also measured in hydrogen atmosphere at 450 degrees C.

  • 2.
    Arjmand, Mehdi
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Liu, Longcheng
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Neretnieks, Ivars
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Exergetic efficiency of high-temperature-lift chemical heat pump (CHP) based on CaO/CO2 and CaO/H2O working pairs2013In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 37, no 9, p. 1122-1131Article in journal (Refereed)
    Abstract [en]

    The use of reversible chemical reactions in recuperation of heat has gained significant interest due to higher magnitude of reaction heat compared to that of the latent or sensible heat. To implement chemical reactions for upgrading heat, a chemical heat pump (CHP) may be used. A CHP uses a reversible chemical reaction where the forward and the reverse reactions take place at two different temperatures, thus allowing heat to be upgraded or degraded depending on the mode of operation. In this work, an exergetic efficiency model for a CHP operating in the temperature-level amplification mode has been developed. The first law and the exergetic efficiencies are compared for two working pairs, namely, CaO/CO2 and CaO/H2O for high-temperature high-lift CHPs. The exergetic efficiency increases for both working pairs with increase in task, TH, decrease in heat source, TM, and increase in condenser, TL, temperatures. It is also observed that the difference in reaction enthalpies and specific heats of the involving reactants affects the extent of increase or decrease in the exergetic efficiency of the CHP operating for temperature-level amplification.

  • 3. Fan, L.
    et al.
    He, C.
    Zhu, Binzhu
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Hubei University Wuhan, China.
    Role of carbonate phase in ceria-carbonate composite for low temperature solid oxide fuel cells: A review2016In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114XArticle in journal (Refereed)
    Abstract [en]

    Ceria-salt composites represent one type of promising electrolyte candidates for low temperature solid oxide fuel cells (LT-SOFCs), in which ceria-carbonate attracts particular attention because of its impressive ionic conductivity and unique hybrid ionic conduction behavior compared with the commonly used single-phase electrolyte materials. It has been demonstrated that the introduction of carbonate in these new ceria-based composite materials initiates multi new functionalities over single-phase oxide, which therefore needs a comprehensive understanding and review focus. In this review, the roles of carbonate in the ceria-carbonate composites and composite electrolyte-based LT-SOFCs are analyzed from the aspects of sintering aid, electrolyte densification reagent, electrolyte/electrode interfacial 'glue' and sources of super oxygen ionic and proton conduction, as well as the oxygen reduction reaction promoter for the first time. This summary remarks the significance of carbonate in the ceria-carbonate composites for low temperature, 300-600°C, SOFCs and related highly efficient energy conversion applications.

  • 4.
    Gao, Zhan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Mao, Zongqiang
    Wang, Cheng
    Huang, Jianbing
    Liu, Zhixiang
    Composite electrolyte based on nanostructured Ce0.8Sm0.2O1.9 (SDC) for low-temperature solid oxide fuel cells2009In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 33, no 13, p. 1138-1144Article in journal (Refereed)
    Abstract [en]

    Nanostructured Ce0.8Sm0.2O1.9 (SDC) is investigated for low-temperature solid oxide fuel cells based on SDC- 30 wt% (53 mol% Li2CO3:47 mol % Na2CO3) composite electrolyte in this work. SDC is prepared by the combined citrate and EDTA complexing method. X-ray powder diffraction shows that it forms a well-cubic fluorite structure after being sintered at 700 degrees C for 2 h. The particle is about 12 nm detected by the transmission electron microscopy. Conductivity for the composite is much higher than the pure SDC at comparable temperatures. A transition of ionic conductivity occurs at 450 degrees C for the composite electrolyte. The single cells are fabricated by a simple dry-pressing process and tested at 450-600 degrees C. A maximum power density of 900 mW cm(-2) and the open-circuit voltage of 0.92 V are achieved at 600 degrees C. The conduction mechanism has been discussed by comparing the conductivity of composite electrolyte under different conditions. AC impedance for single cell indicates that the electrochemical process involving cathode and anode reactions is the rate-limiting step.

  • 5. Gao, Zhan
    et al.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Development of Direct Methanol Low Temperature Fuel Cells from a Polygeneration, Perspective2011In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 35, p. 690-696Article in journal (Refereed)
  • 6.
    Gao, Zhan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Mao, Zongqiang
    Development of methanol-fueled low-temperature solid oxide fuel cells2011In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 35, no 8, p. 690-696Article in journal (Refereed)
    Abstract [en]

    Low-temperature solid oxide fuel cell (SOFC, 300-600 degrees C) technology fueled by methanol possessing significant importance and application in polygenerations has been developed. Thermodynamic analysis of methanol gas-phase compositions and carbon formation indicates that direct operation on methanol between 450 and 600 degrees C may result in significant carbon deposition. A water steam/methanol ratio of 1/1 can completely suppress carbon formation in the same time enrich H(2) production composition. Fuel cells were fabricated using ceria-carbonate composite electrolytes and examined at 450-600 degrees C. The maximum power density of 603 and 431 mW cm(-2) was achieved at 600 and 500 degrees C, respectively, using water steam/methanol with the ratio of 1/1 and ambient air as fuel and oxidant. These results provide great potential for development of the direct methanol low-temperature SOFC for polygenerations.

  • 7.
    Grönkvist, Stefan
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Sjödin, Jörgen
    Linköping Institute of Technology, Department of Mechanical Engineering, Division of Energy Systems.
    Westermark, Mats
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Models for assessing net CO2 emissions applied on district heating technologies2003In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 27, no 6, p. 601-613Article in journal (Refereed)
    Abstract [en]

    Methodologies to assess the effects of energy projects on global carbon dioxide emissions will be an important feature of a future international carbon dioxide trading system. In this paper, we present and discuss four different models for assessing the net carbon dioxide emissions resulting from a certain energy project. These models are applied to different district heating technologies. To judge the mitigation performance of a project, the amount of carbon dioxide released in kilograms is expressed per megawatt-hour of useful district heating produced. All the models consider the marginal change caused by the project on the electric power system. The different model perspectives are discussed, and it is shown that the choice of model is very critical for assessing the net carbon dioxide emissions from an energy project.

  • 8.
    Gunasekara, Samman Nimali
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Ignatowicz, Monika
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Chiu, Justin NingWei
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Martin, Viktoria
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Thermal conductivity measurement of erythritol, xylitol, and their blends for phase change material design: A methodological study2019In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 43, no 5, p. 1785-1801Article in journal (Refereed)
    Abstract [en]

    This work presents and discusses a detailed thermal conductivity assessment of erythritol, xylitol, and their blends: 25 mol% erythritol and 80 mol% erythritol using the transient plane source (TPS) method with a Hot Disk Thermal Constants Analyzer TPS‐2500S. Thereby, the thermal conductivities of xylitol, 25 mol% erythritol, 80 mol% erythritol, and erythritol were here found for respectively in the solid state to be 0.373, 0.394, 0.535, and 0.589 W m−1 K−1 and in the liquid state to be 0.433, 0.402, 0.363, and 0.321 W m−1 K−1. These obtained results are comprehensively and critically analyzed as compared to available literature data on the same materials, in the phase change materials (PCMs) design context. This study clearly indicates that these thermal conductivity data in literature have considerable discrepancies between the literature sources and as compared to the data obtained in the present investigation. Primary reasons for these disparities are identified here as the lack of sufficiently transparent and repeatable data and procedure reporting, and relevant standards in this context. To exemplify the significance of such transparent and repeatable data reporting in thermal conductivity evaluations in the PCM design context, here focused on the TPS method, a comprehensive measurement validation is discussed along various residual plots obtained for varying input parameters (ie, the heating power and time). Clearly, the variations in the input parameters give rise to various thermal conductivity results, where choosing the most coherent result requires a sequence of efforts per material, because there are no universally valid conditions. Transparent and repeatable data and procedure reporting are the key to achieve comparable thermal conductivity results, which are essential for the correct design of thermal energy storage systems using PCMs.

    The full text will be freely available from 2020-02-22 10:37
  • 9. Leung, Dennis Y. C.
    et al.
    Yang, Hongxing
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Novel studies on hydrogen, fuel cell and battery energy systems2011In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 35, no 1, p. 1-1Article in journal (Refereed)
  • 10.
    Li, Hailong
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Ji, Xiaoyan
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    A new modification on RK EOS for gaseous CO2 and gaseous mixtures of CO2 and H2O2006In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 30, no 3, p. 135-148Article in journal (Refereed)
    Abstract [en]

    To develop an equation of state with simple structure and reasonable accuracy for engineering application, Redlich-Kwong equation of state was modified for gaseous CO2 and CO2-H2O mixtures. In the new modification, parameter 'a' of gaseous CO2 was regressed as a function of temperature and pressure from recent reliable experimental data in the range: 220-750 K and 0.1-400 MPa. Moreover, a new mixing rule was proposed for gaseous CO2-H2O mixtures. To verify the accuracy of the new modification, densities were calculated and compared with experimental data. The average error is 1.68% for gaseous CO2 and 0.93% for gaseous mixtures of CO2 and H2O, Other thermodynamic properties, such as enthalpy and heat capacities of CO2 and excess enthalpy of gaseous CO2-H2O mixtures, were also calculated; results fit experimental data well, except for the critical region.

  • 11.
    Lu, Yuzheng
    et al.
    Southeast Univ, Sch Energy & Environm, Nanjing 210096, Jiangsu, Peoples R China.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Wang, Jun
    Southeast Univ, Sch Energy & Environm, Nanjing 210096, Jiangsu, Peoples R China.
    Zhang, Yaoming
    Southeast Univ, Sch Energy & Environm, Nanjing 210096, Jiangsu, Peoples R China.
    Li, Junjiao
    Bengbu Inst Business & Technol, Dept Comp Sci, Bengbu 233719, Anhui, Peoples R China.
    Hybrid Power Generation System of Solar Energy and Fuel Cells2016In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, International Journal of Energy Research, Vol. 40, no 6, p. 717-725Article in journal (Refereed)
    Abstract [en]

    This paper introduces the methods of integration of solar energy and low-temperature solid oxide fuel cells. On the one hand, we design the system that integrates the solar photovoltaic cells and fuel cells. On the other hand, solar energy is concentrated to heat up the fuel cell and supply the working temperature at hundreds Celsius degrees by Fresnel lens. Then the fuel conversion efficiency is increased because of gain from the solar energy. Moreover, integration of solar thermal energy power system with the fuel is a good method for resolving the instability of solar energy. CHP (combined heat and power) is another aspect to enhance the design hybrid system overall efficiency. Finally, we present a novel device but built on different scientific principle. It can convert solar energy and chemical energy of fuel to electric energy simultaneously within the same device to integrated solar cell and fuel cell from the device level.

  • 12.
    Raza, Rizwan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ahmad, M. Ashfaq
    Iqbal, Javed
    Akram, N.
    Gao, Zhan
    Javed, Sufyan
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ce-0.8(SmZr)(0.2)O-2-carbonate nanocomposite electrolyte for solid oxide fuel cell2014In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 38, no 4, p. 524-529Article in journal (Refereed)
    Abstract [en]

    A nanocomposite Zr/Sm-codoped ceria electrolyte coated with K2CO3/Na2CO3 was synthesized by a coprecipitation method. The electrochemical study of the two-phase nanocomposite electrolytes with carbonate coated on the doped ceria shows high oxygen ion mobility at low temperatures (300-600 degrees C). The interface between the two constituent phases was studied by electrochemical impedance spectroscopy. Ionic conductivities were also measured with electrochemical impedance spectroscopy. The morphology and structure of composite electrolyte were characterized using field-emission scanning electron microscopy and X-ray diffraction. The fuel cell power density is 700 mW cm(-2), and an open-circuit voltage of 1.00 V is achieved at low temperatures (400-550 degrees C). This codoped approach with a second phase provides a good indication regarding overcoming the challenges of solid oxide fuel cell technology.

  • 13. Riva, Fabio
    et al.
    Rocco, Matteo V.
    Gardumi, Francesco
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Bonamini, Giorgio
    Colombo, Emanuela
    Design and performance evaluation of solar cookers for developing countries: The case of Mutoyi, Burundi2017In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 41, no 14, p. 2206-2220Article in journal (Refereed)
    Abstract [en]

    Here, we propose an approach for supporting the design and performance evaluation phase of solar cooking technologies, to assess their eventual appropriateness for remote rural contexts, before proposing them for local field tests. The approach is based on (1) local context description and analysis, (2) design and construction of the solar cookers, and (3) thermodynamic performance evaluation. We used the approach to analyse 3 cookers for the area of Mutoyi, Burundi: a parabolic, a panel, and a box cooker. From phases 1 and 2, only panel and box cookers emerged as the technically viable solutions: They were sized, optimized, built, and tested. In phase 3, the thermodynamic evaluation indicated that the box cooker is inappropriate, since water does not reach high enough temperature. Instead, the panel cooker shows a Standardized Cooking Power of 46.85W and a stagnation temperature higher than 75 degrees C, which is able to bring the water to the boil when the environmental temperature is higher than 25 degrees C. The thermal efficiency of the cooker resulted equal to 8.13%, while the mean integral temperature T-m remained around 60 degrees C for all the lab test replicates, higher than the minimum internal temperature to cook legumes. The results of the procedure applied to the case study indicate that the panel cooker can be proposed for local field tests with local food and cooking practices, for assessing its final appropriateness on the field.

  • 14.
    Sakellari, Dimitra
    et al.
    KTH, Superseded Departments, Energy Technology.
    Lundqvist, Per Gunnar
    KTH, Superseded Departments, Energy Technology.
    Energy Analysis of a Low-Temperature Heat Pump Heating System in a Single-Family House2004In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 28, no 1, p. 1-12Article in journal (Refereed)
    Abstract [en]

     Energy costs and environmental concerns have made energy optimisation a viable option for buildings. Energy-efficient heating systems together with an effective use of buildings thermal mass and tightness have a significant impact on the energy requirement and on the possibility for sizeable running cost savings. In this study we use the simulation tool TRNSYS-EES to model and analyse the performance of a residential house and the low-temperature heating system that serves its thermal needs. The building is a single-family house with controlled ventilation and the chosen heating system is a hydronic floor heating system connected to an exhaust air heat pump. The aim of the simulation is to study the performance of the building, the heating system and the controls in an integrated manner. Overall, the results indicate that the energy efficiency issue implicates system design and system thinking concerns as well as techno-economic difficulties. Them controls and the choice of the operation mode are of a great importance.

  • 15. Song, Han
    et al.
    Dotzauer, Erik
    Thorin, Eva
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Techno-economic analysis of an integrated biorefinery system for poly-generation of power, heat, pellet and bioethanol2014In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 38, no 5, p. 551-563Article in journal (Refereed)
    Abstract [en]

    Bioethanol is an alternative to fossil fuels in the transportation sector. The use of pellet for heating is also an efficient way to mitigate greenhouse gas emissions. This paper evaluates the techno-economic performance of a biorefinery system in which an existing combined heat and power (CHP) plant is integrated with the production of bioethanol and pellet using straw as feedstock. A two-stage acid hydrolysis process is used for bioethanol production, and two different drying technologies are applied to dry hydrolysis solid residues. A sensitivity analysis is performed on critical parameters such as the bioethanol selling price and feedstock price. The bioethanol production cost is also calculated for two cases with either 10 year or 15 year payback times. The results show that the second case is currently a more feasible economic configuration and reduces production costs by 36.4%-77.3% compared to other types of poly-generation plants that are not integrated into existing CHP plants.

  • 16. Starfelt, Fredrik
    et al.
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Case study of energy systems with gas turbine cogeneration technology for an eco-industrial park2008In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 32, no 12, p. 1128-1135Article in journal (Refereed)
    Abstract [en]

    Eco-industrial parks (EIP) are clusters of industry corporations that collaborate with reusing waste and energy-efficient use of resources with no or minor impact on the environment. This paper presents a case study that examines the feasibility of using gas turbine technology in one industrial park, located in the Dongguan city of the Guangdong province in China. A model of a gas turbine-based combined heat and power (CHP) plant with a heat recovery steam generator for absorption cooling was developed and simulated. A steam-injected gas turbine has been selected in the system to increase electricity production and to generate steam. The study includes performance analysis of the cogeneration plant in terms of thermal efficiency, cost estimation, and greenhouse gas emission. The gas turbine-based cogeneration system has been compared with a baseline reference case that is defined as if all the energy to the industrial park is supplied from the local electricity grid. The results show that the gas turbine-based cogeneration system can reach a total efficiency of 58% and reduce CO, emissions with 12 700 tons per year. A sensitivity analysis on the costs of the system has also been made based on fuel costs and the interest rate, which shows that the investigated system is economically profitable at natural gas prices below 4.4 RMB m(-3) with fixed electricity prices and at electricity prices above 736 RMB MWh(-1) with fixed natural gas prices. The sensitivity analysis based on the interest rate showed that the proposed system is economically feasible with interest rates up to 16%.

  • 17.
    Welsch, Manuel
    et al.
    KTH.
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Hesamzadeh, Mohammad Reza
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Gallachoir, Brian O.
    Deane, Paul
    Strachan, Neil
    Bazilian, Morgan
    Kammen, Daniel M.
    Jones, Lawrence
    Strbac, Goran
    Rogner, Holger
    Supporting security and adequacy in future energy systems: The need to enhance long-term energy system models to better treat issues related to variability2015In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 39, no 3, p. 377-396Article in journal (Refereed)
    Abstract [en]

    As the shares of variable renewable generation in power systems increase, so does the need for, inter alia, flexible balancing mechanisms. These mechanisms help ensure the reliable operation of the electricity system by compensating for fluctuations in supply or demand. However, a focus on short-term balancing is sometimes neglected when assessing future capacity expansions with long-term energy system models. Developing heuristics that can simulate short-term system issues is one way of augmenting the functionality of such models. To this end, we present an extended functionality to the Open Source Energy Modelling System (OSeMOSYS), which captures the impacts of short-term variability of supply and demand on system adequacy and security. Specifically, we modelled the system adequacy as the share of wind energy is increased. Further, we enable the modelling of operating reserve capacities required for balancing services. The dynamics introduced through these model enhancements are presented in an application case study. This application indicates that introducing short-term constraints in long-term energy models may considerably influence the dispatch of power plants, capacity investments, and, ultimately, the policy recommendations derived from such models.

  • 18. Wetterlund, Elisabeth
    et al.
    Pettersson, Karin
    Magnusson, Mimmi
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Implications of system expansion for the assessment of well-to-wheel CO2 emissions from biomass-based transportation2010In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 34, no 13, p. 1136-1154Article in journal (Refereed)
    Abstract [en]

    In this paper we show the effects of expanding the system when evaluating well-to-wheel (WTW) CO2 emissions for biomass-based transportation, to include the systems surrounding the biomass conversion system. Four different cases are considered: DME via black liquor gasification (BLG), methanol via gasification of solid biomass, lignocellulosic ethanol and electricity from a biomass integrated gasification combined cycle (BIGCC) used in a battery-powered electric vehicle (BPEV). All four cases are considered with as well as without carbon capture and storage (CCS). System expansion is used consistently for all flows. The results are compared with results from a conventional WTW study that only uses system expansion for certain co-product flows. It is shown that when expanding the system, biomass-based transportation does not necessarily contribute to decreased CO2 emissions and the results from this study in general indicate considerably lower CO2 mitigation potential than do the results from the conventional study used for comparison. It is shown that of particular importance are assumptions regarding future biomass use, as by expanding the system, future competition for biomass feedstock can be taken into account by assuming an alternative biomass usage. Assumptions regarding other surrounding systems, such as the transportation and the electricity systems are also shown to be of significance. Of the four studied cases without CCS, BIGCC with the electricity used in a BPEV is the only case that consistently shows a potential for CO2 reduction when alternative use of biomass is considered. Inclusion of CCS is not a guarantee for achieving CO2 reduction, and in general the system effects are equivalent or larger than the effects of CCS. DME from BLG generally shows the highest CO2 emission reduction potential for the biofuel cases. However, neither of these options for biomass-based transportation can alone meet the needs of the transport sector. Therefore, a broader palette of solutions, including different production routes, different fuels and possibly also CCS, will be needed.

  • 19. Wolf, J.
    et al.
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Parametric study of chemical looping combustion for tri-generation of hydrogen, heat, and electrical power with CO2 capture2005In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 29, no 8, p. 739-753Article in journal (Refereed)
    Abstract [en]

    In this article, a novel cycle configuration has been studied, termed the extended chemical looping combustion integrated in a steam-injected gas turbine cycle. The products of this system are hydrogen, heat, and electrical power. Furthermore, the system inherently separates the CO2 and hydrogen that is produced during the combustion. The core process is an extended chemical looping combustion (exCLC) process which is based on classical chemical looping combustion (CLC). In classical CLC, a solid oxygen carrier circulates between two fluidized bed reactors and transports oxygen from the combustion air to the fuel; thus, the fuel is not mixed with air and an inherent CO2 separation occurs. In exCLC the oxygen carrier circulates along with a carbon carrier between three fluidized bed reactors, one to oxidize the oxygen carrier, one to produces and separate the hydrogen, and one to regenerate the carbon carrier. The impacts of process parameters, such as flowrates and temperatures have been studied on the efficiencies of producing electrical power, hydrogen, and district heating and on the degree of capturing CO2. The result shows that this process has the potential to achieve a thermal efficiency of 54% while 96% of the CO2 is captured and compressed to 110 bar.

  • 20.
    Yan, Jinyue
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Chou, S. K.
    Dahlquist, E.
    Recent progress in sustainable energy systems2013In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 37, no 15, p. 1937-1938Article in journal (Other academic)
  • 21.
    Yan, Jinyue
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Dahlquist, E.
    Malardalen Univ, IGEC III, Vasteras, Sweden..
    Yang, H.
    Hong Kong Polytech Univ, Hong Kong, Hong Kong, Peoples R China..
    Guest editorial for a special issue on green energy2008In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 32, no 12, p. 1065-1065Article in journal (Other academic)
  • 22. Zhe, Yuan
    et al.
    Qizhao, Lin
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Thermodynamic analysis of ITSOFC co-generation system fueled by ethanol2011In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 35, no 12, p. 1025-1031Article in journal (Refereed)
    Abstract [en]

    Solid oxide fuel cell (SOFC) is a true multi-fuel energy conversion device that produces electricity directly from fuel through electrochemical reactions. In this paper, the performance of intermediate temperature SOFC (ITSOFC) fueled by ethanol was analyzed. The exhaust gas of SOFC has high value in use. So SOFC is integrated into a hybrid system with other power system for co-generations. Based on a mathematical model of ITSOFC, the steady-state model of each designed system was presented. Results show that a co-generation system can achieve high efficiency. The research on SOFC fueled by ethanol is useful for the application of new and renewable energy. The results of this research can be useful in design and application for SOFC in co-generations.

  • 23.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Applications of hydrofluoride ceramic membranes for advanced fuel cell technology2000In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 24, no 1, p. 39-49Article in journal (Refereed)
    Abstract [en]

    New types of materials, hydrofluoride-alumina ceramic composites containing one hydride component, CaH2, have been studied for fuel cell applications. Excellent fuel cell performances were achieved for a peak power density of 180 mW cm(-2) at 300 mA cm(-2), and a short-circuit current density near 1000 mA cm(-2). In fuel cell measurements the conductivity and ionic transport properties of the hydrofluoride-based electrolytes have also been investigated. During fuel cell operation, water was often observed at the cathode (air side), indicating that proton conduction occurs in these electrolyte materials. The experiments show an interesting chance for the future development of innovative fuel cell technology for commercialization.

  • 24.
    Zhu, Bin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Next generation fuel cell R&D2006In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 30, no 11, p. 895-903Article in journal (Refereed)
    Abstract [en]

    The material innovations and developments can play a key role in realizing solid oxide fuel cell (SOFC) commercialization. However, it seems missing in the long SOFC R&D strategy. Recent R&D. on innovative ceria-based composites (CBCs) make a breakthrough and open a new research subject on low-temperature (300-600 degrees C) SOFCs. Low temperatures create many freedoms to develop next generation fuel cell technology for commercialization.

  • 25.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Solid oxide fuel cell (SOFC) technical challenges and solutions from nano-aspects2009In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 33, no 13, p. 1126-1137Article in journal (Refereed)
    Abstract [en]

    The classical (over 100 years) oxygen ion conductor and theory for solid oxide fuel cells (SOFCs) have met critical challenges, which are caused by the electrolyte material, the heart of the SOFC. Ionic conductivity of 0.1 S cm(-1) as a basic requirement limits conventional SOFC electrolyte material, yttrium stabilized zirconia (YSZ) functioning at ca. 1000 degrees C. Such high temperature prevents SOFC technology from commercialization. Design and development of materials functioning at low temperatures are therefore a critical challenge. State of the art of the nanotechnology remarks a great potential for SOFCs. Through a review of typical SOFC electrolyte materials and analysis of the ionic conduction theory as well as constrains and disadvantages in single-phase materials, the need for design, development and theory of new materials are obvious. Our approach is to design and develop two-phase materials and functionalities at interfaces between the constituent phases in nanotech-based composites, that is nanocomposites. The nano- and composite technologies can realize superionic conduction by constructing the interfaces as 'ion highways'. Manipulation of the interphases of the nanocomposites can overcome SOFC challenges and thus enhance and improve material conductivity and FC performance at significantly lower temperatures (300-600 degrees C).

  • 26.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Bai, X. Y.
    Chen, G. X.
    Yi, W. M.
    Bursell, Martin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Fundamental study on biomass-fuelled ceramic fuel cell2002In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 26, no 1, p. 57-66Article in journal (Refereed)
    Abstract [en]

    Recent development in the advanced intermediate temperature (400 to 700degreesC) ceramic fuel cell (CFC) research brings up feasibility and new opportunity to develop innovative biomass-fuelled CFC technology. This work focuses on fundamentals of the biomass-fuelled CFCs based on available biofuel resources through thermochemical conversion technologies. Both real producer gas from biomass gasification and imitative compounded gas were used as the fuel to operate the CFCs in the biomass CFC testing station. The composition of the fuel gas was varied in a wide range of practices of the present conversion technology both in KTH and Shandong Institute of Technology (SDIT), CFC performances were achieved between 100 and 700 mW cm(-2) at 600-800degreesC corresponding to various gas compositions. A high performance close to 400 mW cm(-2) was obtained at 600degreesC for the gas with the composition of H-2 (50 per cent) + CO (15 per cent) + CO2 (15 per cent) + N-2 (20 per cent) and more than 600 mW cm(-2) for the H-2 (55 per cent) + CO (28 per cent) + CO2 (17 per cent) at 700degreesC. This paper presents the experimental results and discusses the fundamentals and future potentiality on the biomass fuelled CFCs.

  • 27.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Lund, Peter
    Aalto Univ, Dept Engn Phys, Sch Sci, FI-00076 Espoo, Finland..
    Advanced fuel cells: from materials and technologies to applications2011In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 35, no 12, p. 1023-1024Article in journal (Other academic)
1 - 27 of 27
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