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  • 3851. Zheng, H.
    et al.
    Wang, C.
    Liu, Qingming
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration. Guangdong University of Technology, China.
    Tian, Z.
    Fan, X.
    Thermal performance of copper foam/paraffin composite phase change material2018In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 157, p. 372-381Article in journal (Refereed)
    Abstract [en]

    Phase change materials are promising options for thermal energy storage and thermal energy devices. However, their low thermal conductivity lowers their charging and discharging rate. In this paper, copper foam was utilized to enhance the thermal performance of the paraffin. A visible experimental device was built to investigate the melting behavior of paraffin with and without copper foam. The effect of the heating position on the thermal performance of copper foam/paraffin composite phase change material (CPCM) was also discussed. The heat transfer characteristics including solid-liquid interface development, temperature distribution and wall temperature of the heater were tested and recorded. In addition, a numerical model was established using one-temperature volume averaging method to analyze the melting process of the CPCM. The experimental results showed that the total melting time of the CPCM was 20.5% shorter than that of pure paraffin, and the CPCM heated at the top melted slowest and reached the biggest temperature difference in the three heating conditions, so the effect of natural convection on the melting process of the CPCM could not be neglected. A two dimensional numerical simulation was also performed to analyze the melting behavior of CPCM, and the numerical results were well consistent with the experimental data.

  • 3852. Zheng, M.
    et al.
    Guccione, Salvatore
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Politecnico di Torino, Italy.
    Fontalvo, A.
    Coventry, J.
    Pye, J.
    Exergy analysis of the impact of a heat exchanger on performance of an integrated sodium-salt CSP plant2022In: SOLARPACES 2020: 26th International Conference on Concentrating Solar Power and Chemical Energy Systems, AIP Publishing , 2022, Vol. 2445Conference paper (Refereed)
    Abstract [en]

    High-temperature receivers are critical for third-generation (Gen3) Concentrating Solar Power (CSP) technology to achieve high system efficiencies, and play the role of converting concentrated sunlight into heat. In this paper, two CSP systems with different working fluids in the receiver are examined in order to achieve identical supply of heat to the power block: a direct high-temperature chloride salt system and an indirect high-temperature sodium receiver with an associated heat exchanger to heat the same chloride salt. The presented numerical model indicates that the indirect sodium-salt system has a 4.37% higher exergy efficiency than the direct chloride salt system. The exergy destruction in the added sodium-salt heat exchanger was only 0.54%, which did not outweigh the performance benefits gained from using a sodium receiver, when compared to the direct salt case with no heat exchanger. Even at lower DNIs, the better heat-transfer characteristics of the sodium are responsible for its improved performance compared to salt in the receivers.

  • 3853. Zheng, Yifeng
    et al.
    Xia, Chen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Dong, Wenjing
    Li, Junjiao
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Scaling up and characterization of engineering single-layer fuel cells2016In: Energy Technology, ISSN 2194-4288, Vol. 4, no 8, p. 967-972Article in journal (Refereed)
    Abstract [en]

    Single-layer fuel cells (SLFCs) are the product of recent advances in low-temperature solid-oxide fuel cell (SOFC) research and development. Conventional three-layer materials comprising an anode, an electrolyte, and a cathode have been replaced by one-layer materials that can integrate all of the functions of fuel cell anodes, electrolytes, and cathodes into one function. Excellent performance, simple technology, and ultra-low cost have increased the potential of SLFCs for commercialization. Therefore, methods should be developed to scale up this innovative and advanced SOFC technology for engineering use and further commercial applications. This work reports the scaling up of an SLFC through powder material preparation, pulp preparation and tape casting, cold-press shaping, hot pressing, and final surface reduction to fabricate 6cmx6cm engineering cells with an active area of 25cm(2). Each SLFC delivers approximately 10W of power at 525-550 degrees C. The performance of the device is comparable with or even better than that of conventional SOFCs. A maximum output power of 12.0W (0.48Wcm(-2)) is obtained from the 6cmx6cm SLFC at 550 degrees C. This study develops a scaling-up technology that uses tape casting and hot pressing to enhance the commercial uses of SLFC.

  • 3854.
    Zhong, Yifeng
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Hydrogen Fuel Cell Lifetime Simulation in Marine Applications2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Maritime transportation emits about 3% of global greenhouse gas, International Maritime Organization (IMO) aims to reduce shipping’s emissions by 50% with respect to 2008 levels. Proton exchange membrane fuel cells (PEMFCs) are considered among the most promising clean technologies for decarbonizing the maritime sector. One of the challenges for commercial application of PEMFCs is their limited durability. The purpose of this thesis was to assess the most significant degradation mechanisms and operating conditions of the PEMFC in marine applications, including membrane and catalyst layer degradation during idle, start-stop cycles, and dynamic load cycles, and to build a model to forecast the lifetime.A semi-empirical approach was developed to evaluate the PEMFC lifetime through a 2D COMSOL model. The model takes into account the empirical relationships for membrane conductivity loss and electrochemical surface area (ECSA) decay as functions of cycling numbers, aging process, and idling time. The 2D model has been validated with the experimental data in the literature and are also compared with a previous 1D model. The polarization curves show the voltage output against current density, lifetime is evaluated using a 10% voltage reduction criterion at the current density 0.6 A/cm2.An improved ECSA degradation model with variable load levels increases the lifetime of the ferry in Case 5 from 5500 hours to 7500 hours. Load cycling and idling cause the most severe degradation, but the impact can be reduced by a hybrid system with battery supplement and onshore charging. The lifetime of the ferry in Case 5 has been significantly further improved from 7500 hours to 22500 hours, which is comparable to the 20000-hour lifetime of commercial products for marine applications. Furthermore, membrane thickness effect analysis showed that fuel cells with thinner membranes (such as NR211) have better performance before degradation due to higher proton conductivity, but degrade faster during load cycling due to hydrogen crossover. The results of this research can be extended to help optimize fuel cell, stack and power system designs to avoid worst-case operating conditions and thereby limit fuel cell degradation.

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  • 3855. Zhou, Hui-Ling
    et al.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Tang, Bao-Jun
    Qu, Shen
    Optimal timing for carbon capture retrofitting in biomass-coal combined heat and power plants in China2021In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 293, article id 126134Article in journal (Refereed)
    Abstract [en]

    Industrial decision-makers may wonder about the optimal timing for investing in carbon capture retrofitting in co-firing power plants, faced with uncertain benefits from upcoming China's carbon trading market and potential cost reductions derived from technology innovation. The decision on investment timing relates to the so-called waiting value, considering multiple uncertainties and trade-offs. This article applies a real options-based framework, adapted to deal with the waiting value in the context of multiple uncertainties of carbon market, technical improvements and biomass availability. The problem is solved through an efficient simulation method. The results suggest that the optimal retrofit timing for CCS (carbon capture and storage) in a co-firing CHP will be the year 2033 considering a basic scenario, in which the carbon price is 98 CNY/tonCO(2) (14.5 USS/tonCO(2)) in 2025, the growth rate and volatility are 5% and 7% respectively, and technical improvements are expected every six years and result in a cost reduction of 50%. In addition, we examine the effects of different sub-dimensions in the carbon market and technical improvement on anticipating the retrofit timing. The conclusions of this article provide decision-makers with strategies of adjusting the investment timing in response to their different expectations of market and technology developments. Further practical applications require judgments of future trends made by decision-makers and extensive data of specific cases.

  • 3856.
    Zhou, Yang
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Comparison of Chinese Green Building Standard with Western Green Building standards2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With rapid economic growth and urbanization in China, the Chinese building sector now accounted for a large amount of its energy usage and pollution. In order to minimize the environmental effect, the Ministry of Urban and Rural Development (MOHURD) has set a goal that 30% of all new constructed buildings will be green by 2020.

    This report reviews the Three Star System, the Chinese green building standard developed by the government agency MOHURD in order to promote and regulate green buildings in China. The study is done by comparing the Three Star System with two of its western equivalents, BREEAM and LEED. The technical manual of each standard is studied and compared, results from various researches within the area is also featured in the report.

    The finding of this report is that Three Star System is necessary to fulfill Chinas unique situation with a building sector that consist of high rates of new construction, although the standard is necessary it still need improvement in technical detail and user-friendliness to be at the same level as LEED and BREEAM. Some suggestion are proposed in the report for further development of the Three Star System 

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  • 3857. Zhu, B.
    et al.
    Lund, P. D.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. COMSATS Institute of Information Technology, Pakistan .
    Ma, Y.
    Fan, L.
    Afzal, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Patakangas, J.
    He, Y.
    Zhao, Y.
    Tan, W.
    Huang, Q. -A
    Zhang, J.
    Wang, H.
    Schottky junction effect on high performance fuel cells based on nanocomposite materials2015In: Advanced Energy Materials, ISSN 1614-6832, E-ISSN 1614-6840, Vol. 5, no 8, article id 1401895Article in journal (Refereed)
    Abstract [en]

    A novel fuel cell device based on integrating the Schottky junction effect with the electrochemical principle is designed, constructed, and verified through experiments. It is found that the Schottky junction has a significant effect on the greatly enhanced device performance, and the fuel cell device incorporating the Schottky junction effect reaches a power output of 1000 mW cm-2 at 550 C.

  • 3858.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Nanocomposites for Advanced Fuel Cell Technology2011In: Journal of Nanoscience and Nanotechnology, ISSN 1533-4880, Vol. 11, no 10, p. 8873-8879Article in journal (Refereed)
    Abstract [en]

    NANOCOFC (Nanocomposites for advanced fuel cell technology) is a research platform/network established based on the FP6 EC-China project www.nanocofc.org. This paper reviews major achievements on two-phase nanocomposites for advanced low temperature (300-600 degrees C) solid oxide fuel cells (SOFCs), where the ceria-salt and ceria-oxide composites are common. A typical functional nanocomposite structure is a core-shell type, in which the ceria forms a core and the salt or another oxide form the shell layer. Both of them are in the nano-scale and the functional components. The high resolution TEM analysis has proven a clear interface in the ceria-based two-phase nanocomposites. such interface and interfacial function has resulted in superionic conductivity, above 0.1 S/cm at around 300 degrees C, being comparable to that of conventional SOFC YSZ at 1000 degrees C. Against conventional material design from the structure the advanced nanocomposites are designed by non-structure factors, i.e., the interfaces, and by creating interfacial functionalities between the two constituent phases. These new functional materials show indeed a breakthrough in the SOFC materials with great potential.

  • 3859.
    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, 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).

  • 3860.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Hubei University, 430062, Wuhan, PR China.
    Basile, Angelo
    Tseng, Chung-Jen
    Materials as a player in hydrogen and fuel cell technologies: Preface to the special issue section2017In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 42, no 34, p. 22090-22090Article in journal (Other academic)
  • 3861.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Hubei University, China.
    Fan, L.
    Deng, H.
    He, Y.
    Afzal, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Dong, W.
    Yaqub, A.
    Janjua, N. K.
    LiNiFe-based layered structure oxide and composite for advanced single layer fuel cells2016In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 316, p. 37-43Article in journal (Refereed)
    Abstract [en]

    A layered structure metal oxide, LiNi0.1Fe0.90O2-δ (LNF), is explored for the advanced single layer fuel cells (SLFCs). The temperature dependent impedance profiles and concentration cells (hydrogen concentration, oxygen concentration, and H2/air atmospheres) tests prove LNF to be an intrinsically electronic conductor in air while mixed electronic and proton conductor in H2/air environment. SLFCs constructed by pure LNF materials show significant short circuiting reflected by a low device OCV and power output (175 mW cm-2 at 500°C) due to high intrinsic electronic conduction. The power output is improved up to 640 and 760 mW cm-2, respectively at 500 and 550°C by compositing LNF with ion conducting material, e.g., samarium doped ceria (SDC), to balance the electronic and ionic conductivity; both reached at 0.1 S cm-1 level. Such an SLFC gives super-performance and simplicity over the conventional 3-layer (anode, electrolyte and cathode) FCs, suggesting strong scientific and commercial impacts.

  • 3862.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    He, Y.
    Zhao, Y.
    Wang, H.
    A commercial lithium battery LiMn-oxide for fuel cell applications2014In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 126, p. 85-88Article in journal (Refereed)
    Abstract [en]

    Hereby we report first a commercial lithium battery LiMn-oxide (LMO) positive electrode material for fuel cell applications. The obtained LMO can be used for both anode and cathode in a three-layer fuel cell, but displays low electro-catalytic activity and power output. Using a nanocomposite approach we have significantly improved the cell performance from tens mW cm-2 up to 210 mW cm-2, which is technically useful for low temperature (bellow 600 °C) ceramic fuel cells. We also constructed single-layer fuel cell using the LMO/SDC-metal oxide composite and achieved even better performances than those for conventional anode-electrolyte-cathode three-layer fuel cells.

  • 3863.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lund, Peter
    Breakthrough fuel cell technology using ceria-based multi-functional nanocomposites2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 106, p. 163-175Article in journal (Refereed)
    Abstract [en]

    Recent scientific and technological advancements have provided a wealth of new information about solid oxide-molten salt composite materials and multifunctional ceria-based nano-composites for advanced fuel cells (NANOCOFC). NANOCOFC is a new approach for designing and developing of multi-functionalities for nanocomposite materials, especially at 300-600 degrees C. NANOCOFC and low temperature advanced ceramic fuel cells (LTACFCs) are growing as a new promising area of research which can be explored in various ways. The ceria-based composite materials have been developed as competitive electrolyte candidates for low temperature ceramic fuel cells (LTCFCs). In the latest developments, multifunctional materials have been developed by integrating semi- and ion conductors, which have resulted in an emerging insight knowledge concerned with their R&D on single-component electrolyte-free fuel cells (EFFCs) - a breakthrough fuel cell technology. A homogenous component/layer of the semi- and ion conducting materials can realize fuel cell all functions to avoid using three components: anode, electrolyte and cathode, i.e. "three in one" highlighted by Nature Nanotechnology (2011). This report gives a short review and advance knowledge on worldwide activities on the ceria-based composites, emphasizing on the latest semi-ion conductive nanocomposites and applications for new applied energy technologies. It gives an overview to help the audience to get a comprehensive understanding on this new field.

  • 3864.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Zhao, Yufeng
    Tan, Wenyi
    Xiong, Dingbang
    Wang, Hao
    Functional semiconductor-ionic composite GDC-KZnAl/LiNiCuZnOx for single-component fuel cell2014In: RSC Advances, E-ISSN 2046-2069, Vol. 4, no 20, p. 9920-9925Article in journal (Refereed)
    Abstract [en]

    The research activities on single-component fuel cells (SCFCs) have opened new doors for keeping ahead with two major areas of focus: improvement of SCFC performances by contributing new materials, and scientific understanding of the SCFC nature and operation mode. The present work reports the exploitation of new material composed of the Gd doped ceria-KAlZn-oxide (GDC-KAZ) and the LiNiCuZn-oxide (LNCZ), combining ionic and semiconducting properties for SCFCs. A new method is first used through an internal electron-hole redox cycle resulting in no net electrons to avoid ceria electronic conduction problems thus to develop an excellent GDC-KAZ electrolyte. Its ionic conductivity, 0.08 S cm(-1) at 600 degrees C, is ten times higher than that of GDC. The SCFC using the GDC-KAZ-LNCZ materials exhibits a remarkable electrochemical performance of 628 mW cm(-2) at 580 degrees C, significantly higher than that of conventional three-component (anode/electrolyte/cathode) fuel cells. The results bring about a new cost-effective and robust system with significant scientific and economic consequences for the fuel cell field.

  • 3865.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Faculty of Physics and Electronic Science, Hubei University, Wuhan, Hubei, China.
    Huang, Yizhong
    Fan, L.
    Ma, Y.
    Wang, Baoyuan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Faculty of Physics and Electronic Science, Hubei University, Wuhan, Hubei, China.
    Xia, Chen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Afzal, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Zhang, B.
    Dong, W.
    Wang, H.
    Lund, P. D.
    Novel fuel cell with nanocomposite functional layer designed by perovskite solar cell principle2016In: Nano Energy, ISSN 2211-2855, Vol. 19, p. 156-164Article in journal (Refereed)
    Abstract [en]

    A novel fuel-to-electricity conversion technology resembling a fuel cell has been developed based on the perovskite solar cell principle using a perovskite, e.g. La0.6Sr0.4Co0.2Fe0.8O3-δ and an ionic nanocomposite material as a core functional layer, sandwiched between n- and p-conducting layers. The conversion process makes use of semiconductor energy bands and junctions properties. The physical properties of the junction and alignment of the semiconductor energy band allow for direct ion transport and prevent internal electronic short-circuiting, while at the same time avoiding losses at distinct electrolyte/electrode interfaces typical to conventional fuel cells. The new device achieved a stable power output of 1080mWcm-2 at 550°C in converting hydrogen fuel into electricity.

  • 3866.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Li, S.
    Sun, X. L.
    Sun, J. C.
    Fuel Cell and Electrolysis Studies with Dual Phase Proton and Oxide Ion Conduction2012In: Molten Salts and Ionic Liquids: Never the Twain?, John Wiley & Sons, 2012, p. 407-417Chapter in book (Refereed)
  • 3867.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Goeta Technology Development International, Sweden .
    Liu, Xiangrong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Goeta Technology Development International, Sweden .
    Zhu, Z.
    Ljungberg, R.
    Development of low temperature solid oxide fuel cells2006In: Proceedings of 4th International ASME Conference on Fuel Cell Science, Engineering and Technology, 2006Conference paper (Refereed)
    Abstract [en]

    Based on innovative ceria-based composite (CBC) material advantages we have made strong efforts to make technical developments on scaling up material production, fabrication technologies on large cells and stack operated at low temperatures (300 to 600°C). Next generation materials for solid oxide fuel cells (SOFCs) have been developed based on abundant natural resources of the industrial grade mixed rare-earth carbonates named as LCP. Here we show the LCP-based materials used as functional electrolytes to achieve excellent fuel cell performances, 300-800 mWcm2 for low temperatures, exhibiting a great availability for industrialization and commercialization. Copyright

  • 3868.
    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, ISSN 0363-907X, E-ISSN 1099-114X, Vol. 35, no 12, p. 1023-1024Article in journal (Other academic)
  • 3869.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lund, Peter
    Helsinki Univ Technol, FI-02015 Espoo, Finland..
    Mao, Zongqiang
    Tsinghua Univ, Inst Nucl & New Energy Technol, Beijing 100084, Peoples R China..
    Basile, Angelo
    Univ Calabria, ITM, Italian Natl Res Council, CNR, I-87030 Arcavacata Di Rende, CS, Italy..
    Special IJHE issue from HyForum 2008 conference2010In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 35, no 7, p. 2579-2579Article in journal (Other academic)
  • 3870.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Lund, Peter
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Patakangas, Janne
    Huang, Qiu-An
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Singh, Manish
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    A new energy conversion technology based on nano-redox and nano-device processes2013In: Nano Energy, ISSN 2211-2855, Vol. 2, no 6, p. 1179-1185Article in journal (Refereed)
    Abstract [en]

    Electrolyte-separator-free fuel cell (EFFC) is a new emerging energy conversion technology. The EFFC consists of a single-component of nanocomposite material which works as a one-layer fuel cell device contrary to the traditional three-layer anode-electrolyte-cathode structure, in which an electrolyte layer plays a critical role. The nanocomposite of a single homogenous layer consists of a mixture of semiconducting and ionic materials that provides the necessary electrochemical reaction sites and charge transport paths for a fuel cell. These can be accomplished through tailoring ionic and electronic (n, p) conductivities and catalyst activities, which enable redox reactions to occur on nano-particles and finally accomplish a fuel cell function.

  • 3871.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ma, Ying
    KTH, School of Information and Communication Technology (ICT), Material Physics, Functional Materials, FNM.
    Wang, Xiaodi
    KTH, School of Information and Communication Technology (ICT), Material Physics, Functional Materials, FNM.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Qin, Haiying
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    A fuel cell with a single component functioning simultaneously as the electrodes and electrolyte2011In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 13, no 3, p. 225-227Article in journal (Refereed)
    Abstract [en]

    A fuel cell device is realized by using a single component of lithium nickel oxide and gadolinium doped ceria (LiNiO2-GDC) composite material, a mixture of electronic and ionic conductors, when nickel foam and silver paste are attached to each surface of the single component pellet as current collectors. This simple fuel cell construction with only one component showed the same or even better performances compared to conventional three-component MEA (membrane electrolyte assembly) fuel cell using GDC as electrolyte. The maximum power density of 450 mW/cm(2) has been achieved at 550 degrees C for the single component fuel cell.

  • 3872.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Mat, Mahmut D.
    Studies on Dual Phase Ceria-based Composites in Electrochemistry2006In: International Journal of Electrochemical Science, E-ISSN 1452-3981, Vol. 1, no 8, p. 383-402Article, review/survey (Refereed)
    Abstract [en]

    The ceria-based dual-phase composites have been recently developed as functional electrolytes successful for intermediate and low temperature solid oxide fuel cell applications. These composite materials showed many unique advantages over the conventional single-phase electrolytes, such as superionic conduction in two-phase interfaces, dual proton and oxygen ion conduction resulting in extremely high ion conductivity and high current outputs in fuel cell and other applications, e. g. electrolysis. Interfacial superionic conduction is a characteristic for high conducting dual-phase composites. The composite approach can combine or integrate multi-ion functions, typically, dual H(+) and O(2-)conduction together to enhance the material conductivity and device performance. Dual or hybrid H+ and O(2-)conduction is based on a consideration that both proton (H+) and oxygen ion (O(2-)) are the fuel cell source ions. Proton conduction is important for LTSOFCs since it can be activated easier than oxygen ions in the low temperature (LT, 300-600 degrees C) region. The superionic conduction, dual phase proton and oxygen ion transport make significant conduction and electrical contributions for electrochemical devices. This paper makes a review on these recent studies.

  • 3873.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Qin, Haiying
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Liu, Qinghua
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Patakangas, J
    Lund, P
    A single-component fuel cell reactor2011In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 36, no 14, p. 8536-8541Article in journal (Refereed)
    Abstract [en]

    We report here a single-component reactor consisting of a mixed ionic and semi-conducting material exhibiting hydrogen-air (oxygen) fuel cell reactions. The new single-component device was compared to a conventional three-component (anode/electrolyte/cathode) fuel cell showing at least as good performance. A maximum power density of 300-600 mW cm(-2) was obtained with a LiNiZn-oxide and ceria-carbonate nanocomposite material mixture at 450-550 degrees C. Adding a redox catalyst element (Fe) resulted in an improvement reaching 700 mW cm(-2) at 550 degrees C.

  • 3874.
    Zhu, Bin
    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.
    Abbas, Ghazanfar
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Singh, Manish
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    An Electrolyte-Free Fuel Cell Constructed from One Homogenous Layer with Mixed Conductivity2011In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 21, no 13, p. 2465-2469Article in journal (Refereed)
    Abstract [en]

    Rather than using three layers, including an electrolyte, a working fuel cell is created that employs only one homogenous layer with mixed conductivity. The layer is a composite made from a mixture of metal oxide, Li(0.15)Ni(0.45)Zn(0.4) oxide, and an ionic conductor; ion-doped ceria. The single-component layer has a total conductivity of 0.1-1 S cm(-1) and exhibits both ionic and semiconducting properties. This homogenous one-layer device has a power output of more than 600 mW cm(-2) at 550 degrees C operating with H(2) and air. Overall conversion is completed in a similar way to a traditional fuel cell, even though the device does not include the electrolyte layer critical for traditional fuel-cell technologies using the three-component anode-electrolyte-cathode structure.

  • 3875.
    Zhu, Bin
    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.
    Liu, Qinghua
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Qin, Haiying
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Zhu, Zhigang
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Singh, Manish
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lund, Peter
    A new energy conversion technology joining electrochemical and physical principles2012In: RSC Advances, ISSN 2046-2069, Vol. 2, no 12, p. 5066-5070Article in journal (Refereed)
    Abstract [en]

    We report a new energy conversion technology joining electrochemical and physical principles. This technology can realize the fuel cell function but built on a different scientific principle. The device consists of a single component which is a homogenous mixture of ceria composite with semiconducting materials, e.g. LiNiCuZn-based oxides. The test devices with hydrogen and air operation delivered a power density of 760mWcm(-2) at 550 degrees C. The device has demonstrated a multi-fuel flexibility and direct alcohol and biogas operations have delivered 300-500 mW cm(-2) at the same temperature. Device physics reveal a key principle similar to solar cells realizing the function based on an effective separation of electronic and ionic conductions and phases within the single-component. The component material multi-functionalities: ion and semi-conductions and bi-catalysis to H-2 or alcohol (methanol and ethanol) and air (O-2) enable this device realized as a fuel cell.

  • 3876.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Qin, Haiying
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Single-component and three-component fuel cells2011In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 196, no 15, p. 6362-6365Article in journal (Refereed)
    Abstract [en]

    Single-component and three-component fuel cell devices have been studied using mixed ionic and electronic conductor. The three-component fuel cell means a conventional fuel cell which is the configuration consists of anode, electrolyte and cathode; while the single-component fuel cell uses only one component that can function as the electrodes and electrolyte simultaneously. The single-component fuel cell showed the same or even better performance compared to conventional three-component fuel cell. A maximum power density of 700 mW cm(-2) has been achieved by the single-component fuel cell at 550 degrees C.

  • 3877.
    Zhu, Bin
    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.
    Qin, Haiying
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Liu, Qinghua
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fuel cells based on electrolyte and non-electrolyte separators2011In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 4, no 8, p. 2986-2992Article in journal (Refereed)
    Abstract [en]

    In the long-history of fuel cell R&D, the electrolyte is an essential part in a three-component configuration because it separates the anode and cathode to realize the fuel cell's functions. We report here non-electrolyte separator fuel cells (NEFCs) compared with electrolyte based fuel cells (EBFCs). The NEFC consists of single- or dual-components based on mixed ionic and semi-conductors but with no electrolyte separator. A maximum power density of 680 mW cm(-2) has been achieved by the NEFC at 550 degrees C. The NEFCs exhibit performances comparable to, and in some cases even better than, those of conventional EBFCs. The design of NEFCs, new material functionalities and device performances may contribute to new fuel cell R&D.

  • 3878.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Institute of Materials and Technology, Dalian Maritime University, China .
    Sun, J.
    Sun, X.
    Li, S.
    Gao, W.
    Liu, Xiangrong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Goeta Technology Development International, Sweden .
    Zhu, Z.
    Compatible cathode materials for high performance low temperature (300-600°C) solid oxide fuel cells2006In: Proceedings of 4th International ASME Conference on Fuel Cell Science, Engineering and Technology, FUELCELL2006, 2006Conference paper (Refereed)
    Abstract [en]

    We have made extensive efforts to develop various compatible electrode materials for the ceria-based composite (CBC) electrolytes, which have been, reported as most advanced LTSOFC electrolyte materials (Zhu, 2003). The electrode materials we have investigated can be classified as four categories: i) LSCCF (LaSrCoCaFeO) and BSCF perovskite oxides applied for our CBC electrolyte LTSOFCs; ii) LFN (LaFeO-based oxides, e.g. LaFe0.8Ni 0.2O3) perovskite oxides; iii) lithiated oxides: e.g. LiNiOx, LiVOx or LiCuOx are typical cathode examples for the CBC LTSOFCs; iv) other mixed oxide systems, most common in a mixture of two-oxide phases, such CuOx-NiOx, CuO-ZnO etc. systems with or without lithiation are developed for the CBC systems, especially for direct alcohol LTSOFCs. These cathode materials used for the CBC electrolyte LTSOFCs have demonstrated excellent performances at 300-600°C, e.g. 1000 mWcm-2 was achieved at 580°C. The LTSOFCs can be operated with a wide range of fuels, e.g. hydrogen, methanol, ethanol etc with great potential for applications.

  • 3879.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Hubei University, China.
    Wang, Baoyuan
    Wang, Yi
    Raza, Rizwan
    Tan, Wenyi
    Kim, Jung-Sik
    van Aken, Peter A.
    Lund, Peter
    Charge separation and transport in La0.6Sr0.4Co0.2Fe0.8O3-delta and ion-doping ceria heterostructure material for new generation fuel cell2017In: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 37, p. 195-202Article in journal (Refereed)
    Abstract [en]

    Functionalities in heterostructure oxide material interfaces are an emerging subject resulting in extraordinary material properties such as great enhancement in the ionic conductivity in a heterostructure between a semiconductor SrTiO3 and an ionic conductor YSZ (yttrium stabilized zirconia), which can be expected to have a profound effect in oxygen ion conductors and solid oxide fuel cells [1-4]. Hereby we report a semiconductorionic heterostructure La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF) and Sm-Ca co-doped ceria (SCDC) material possessing unique properties for new generation fuel cells using semiconductor-ionic heterostructure composite materials. The LSCF-SCDC system contains both ionic and electronic conductivities, above 0.1 S/cm, but used as the electrolyte for the fuel cell it has displayed promising performance in terms of OCV (above 1.0 V) and enhanced power density (ca. 1000 mW/cm(2) at 550 degrees C). Such high electronic conduction in the electrolyte membrane does not cause any short-circuiting problem in the device, instead delivering enhanced power output. Thus, the study of the charge separation/transport and electron blocking mechanism is crucial and can play a vital role in understanding the resulting physical properties and physics of the materials and device. With atomic level resolution ARM 200CF microscope equipped with the electron energy-loss spectroscopy (EELS) analysis, we can characterize more accurately the buried interface between the LSCF and SCDC further reveal the properties and distribution of charge carriers in the heterostructures. This phenomenon constrains the carrier mobility and determines the charge separation and devices' fundamental working mechanism; continued exploration of this frontier can fulfill a next generation fuel cell based on the new concept of semiconductor-ionic fuel cells (SIFCs).

  • 3880. Zhu, Jing
    et al.
    Deng, Hui
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Dong, Wenjing
    Zhang, Wei
    Li, Junjiao
    Bao, Xujin
    Polymer-assistant ceramic nanocomposite materials for advanced fuel cell technologies2017In: Ceramics International, ISSN 0272-8842, E-ISSN 1873-3956, Vol. 43, no 7, p. 5484-5489Article in journal (Refereed)
    Abstract [en]

    In this study, nanocomposites of LaCePr-oxide (LCP) and Ni0.8Co0.15Al0 05LIO2-delta (NCAL) with different contents of polyvinylidene fluoride (PVDF) were prepared and applied to solid oxide fuel cells. The composite materials were characterized by X-ray diffraction analysis (XRD), scanning electron microscope (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and electrochemical impedance spectrum (EIS). The effect of PVDF concentration on the conductivity and performance of the fuel cells was investigated. It was found that PVDF plays a template role of pore forming in the nanocomposites, and the changed microstructure by as-formed pores greatly influences the electrochemical property of the nanocomposites. The cell with 3 wt% PVDF heat-treated at 210 C-omicron achieved the highest power density of 982 mW cm(-2) at 520 C-omicron, which enhanced performance by more than 57% than when no heat-treatment was implemented. It is 66% higher than the cell with no PVDF and no heat-treatment. Pores formed by PVDF after heat-treatment enlarged the triple phase boundary (TPB), which results in improved fuel cell performance.

  • 3881.
    Zhuang, Qingyuan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Parametric Study on the Aeroelastic Stability of Rotor Seals2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Labyrinth seals are widely used in rotating machinery and have been shown to experience aeroelastic instabilities. The rapid development of computational fluid dynamics now provides a high fidelity approach for predicting the aeroelastic behavior of labyrinth seals in three dimension and exhibits great potential within industrial application, especially during the detailed design stages. In the current publication a time-marching unsteady Reynolds- averaged Navier-Stokes solver was employed to study the various historically identified parameters that have essential influence on the stability of labyrinth seals. Advances in understanding of the related aeroelastic (flutter) phenomenon were achieved based on extensive yet economical numerical analysis of a simplified seal model. Further, application of the same methodology to several realistic gas turbine labyrinth seal designs confirmed the perceived knowledge and received agreements from experimental indications. Abbott’s criteria in describing the labyrinth seal aeroelastic behaviors were reaffirmed and further developed. 

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    Zhuang Qingyuan EGI-2012-107MSC EKV923
  • 3882.
    Ziółkowski, Marcin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Potential and challenges of Battery Energy Storage(BESS): The case of Poland2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    According to the “Draft development plan for meeting the current and future electricity demandfor 2023-2032” developed by the Polish Transmission System Operator PSE, the most appropriate solution is to significantly expand the possibilities of energy storage, due to its role as a factor improving the power balancing with the increase of wind farms and photovoltaic (PV) sources. Poland has changed the rules governing the energy industry to encourage energy storage. Few barriers have already been eliminated like double charging of transmission fees, but there is still a big novelty to come and that is the reform of the balancing market. With the introduction of this change many more revenue streams should be available that are already present in other EU countries. The objective of this thesis is to provide a high-level overview of the Polish electricity market, identification of existing legal barriers, assessing the role of battery energy storage systems (BESSs) participating in distinct applications, and evaluating a possible business case considering a foreseeable market evolution. The scope of the study is limited to only one storage option Li-Ion standalone project of 10MW/40MWh at HV Point of Connection. In literature review, there does not seem to be a study on storage in the context of Poland. Hence, identifying the research gaps, an analysis of standalone storage system for grid applications in Poland is performed. In this study the NPV, IRR and PP for different scenarios of available revenue streams is determined to compare current and future business models for techno-economic feasibility for BESS in the context of Poland. Results of the study are as following. In the future scenario under the assumed dispatch strategy and participation in CM, FCR, aFRR availability markets as well as aFRR energy market and wholesale arbitrage, the overall project IRR is around 18% with a payback time of around 5 years. Provided the number of new accessible revenue streams BESS can present a strong business case in Poland.

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  • 3883.
    Zottl, Andreas
    et al.
    AIT, Dept Energy, Business Unit Sustainable Thermal Energy Syst, Vienna, Austria..
    Fleckl, Thomas
    AIT, Dept Energy, Business Unit Sustainable Thermal Energy Syst, Vienna, Austria..
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    GreenHP: Design and Performance of the Next Generation Heat Pump for Retrofitting Buildings2016In: 2016 ASHRAE annual conference papers, AMER SOC HEATING, REFRIGERATING AND AIR-CONDITIONING ENGS , 2016Conference paper (Refereed)
    Abstract [en]

    The GreenHP-project (www.greenhp.eu) aims at developing a new, highly efficient urban heating system based on a high-capacity air-to-water heat pump for retrofitting multi-family houses and commercial buildings. For this purpose, a comprehensive multi-level research approach ranging from new heat pump component designs to advanced system integration concepts is pursued. The proposed GreenHP system will be operated with a natural refrigerant, will interact with large (renewable) energy systems, like the smart grid in particular, and will include renewable energy sources, like photovoltaic and solar thermal. Combining the expertise from leading European research institutes and industry partners allows an integration of advanced fan, compressor and heat exchangers in a compact system. Using the natural refrigerant R290, the consortium aims for a heat pump system with minimum environmental impact and a high operating efficiency to provide a heating capacity of 30 kW (102364 BTU/h). The refrigerant charge of the system is minimised by using aluminium micro-channel tubes in both condenser and evaporator. The use of aluminium for the condenser allows an improved heat exchange compared to conventional steel designs. On the air side of the evaporator highly efficient air fins are developed that are less sensitive to icing. Also the fan is optimised for better handling of icing conditions. A bionic distributor will take care to evenly load the micro-channel tubes of the evaporator with refrigerant. Additionally a new compressor concept is developed, which is integrated in a holistic control strategy for most efficient energy management.

  • 3884. Zurita, A.
    et al.
    Strand, Anna
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Guédez, Rafael
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Escobar, R. A.
    Identifying Optimum CSP plant Configurations for Spot Markets using a Dispatch Optimization Algorithm – A Case Study for Chile2020In: SOLARPACES 2019: International Conference on Concentrating Solar Power and Chemical Energy Systems, AIP Publishing , 2020, Vol. 2303, article id 0028964Conference paper (Refereed)
    Abstract [en]

    This work presents a dispatch optimizer algorithm that seeks to maximize the revenues of a CSP plant by selling electricity to the grid for a case study in Chile. The model comprehends a mixed-integer programming problem in which the operation and performance of the plant are represented by the physics and energy balances of the system. The analysis was applied using meteorological and electrical prices data of Crucero and Polpaico located in northern and central region of Chile, respectively, to couple a perfect forecast of weather and market conditions to the model. Results indicate that it is possible to determine best configurations for CSP plants in terms of solar field size and thermal storage under given electric prices conditions that result in better trade-offs between investment and profits of the plant. In this way, this work also demonstrates the importance of coupling optimized dispatch strategies with financial models, suggesting also that CSP developers could implement these type of optimizers with price forecasting models to evaluate the profitability and viability of their business models.

  • 3885.
    Zurita, Adriana
    et al.
    Pontificia Universidad Católica de Chile.
    Mata-Torres, Carlos
    Pontificia Universidad Católica de Chile.
    Cardemil, José M.
    Pontificia Universidad Católica de Chile.
    Guédez, Rafael
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Escobar, Rodrigo
    Pontificia Universidad Católica de Chile.
    Multi-objective optimal design of solar power plants with storage systems according to dispatch strategy2021In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 237, article id 121657Article in journal (Refereed)
    Abstract [en]

    This study presents a comprehensive analysis evaluating the impact of the dispatch strategy on the optimal design configurations of different combinations of solar power plants with storage. The analysis considers four dispatch profiles (baseload, daylight, night, and daylight and evening), and four technology combinations including a solar PV plant with batteries, a CSP plant with Thermal Storage (TES), a hybrid CSP-PV plant with TES, and a hybrid CSP-PV plant with TES and batteries. Two locations with high and moderate levels of DNI were selected and cost scenarios for 2020 and 2030 were considered. The aim is to determine the competitiveness ranges of each technology combination and establishing the least-cost technological option that allows meeting a dispatch strategy with a certain level of supply guarantee. A multi-objective optimization approach was followed to obtain the trade-off curves that minimize the LCOE and maximize the sufficiency factor in terms of the nominal size of the PV plant, solar multiple, TES size, batteries capacity, and inverter power rate. Results of this work allow determining the influence of the dispatch strategy on the competitiveness of these storage-integrated technology options, giving relevant information concerning under which conditions one technology combination is preferable over another.

  • 3886.
    Älfvåg, Hector
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics. KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Parametric Study of Separation in Outlet Diffuser of Rocket Nozzle Cooling Channel Rig: The Effect of Heat Flux and Angle of Outlet Diffuser for Rectangular-to-Circular Cross Section Transitions2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The use of natural gas with high methane content as rocket fuel has gained substantial industrial attention over the past number of years. Several actors including SpaceX and Blue Origin are developing natural gas powered rocket engines. Attention is also shown from GKN Aerospace, a Sweden-based aerospace engine development company, who together with KTH Royal Institute of Technology has initiated the MERiT project. The project is intended to investigate different aspects of methane powered engines. The project is centered around a physical test rig of a rocket nozzle cooling channel along with an ANSYS CFX simulationmodel of the same rig to investigate the operation. The rig is heated from one side to simulate the boundary conditions of a real rocket nozzle. This report is a follow-up to the previous work by Pettersson (2019), which determined rig design points for two channel geometries (channel 3, channel 4) and studied the behaviours and limitations in regards to overheating, cooling and coking. The channels feature outlet diffusers transitioning from rectangular to circular cross sections. The inputs investigated were mass flow, inlet temperature, outlet pressure and heat flux. Following the discovery of flow separation occurring in the rig at certain design points, it was suggested that a parametric study of the outlet diffuser angle could investigate the effect on separation in the outlet diffuser of the rig channel geometry. This is the task at hand in this thesis, and a complementary investigation on the effect heat flux has on separation is also performed for single selected diffuser angles. To achieve this, the full rig model geometry is first reduced to its core components to reduce simulation run time, and the parametric diffuser is implemented for both channel geometries. The mesh and the model definition is then adjusted to accommodate the changes made, by for example replacing the full rig heater block with a constant heat flux boundary condition. After this, a total of 40 test cases of different diffuser angle and heat flux combinations are used to establish trends in the behaviour of the separation. The results show that separation occurs more easily for the channel 3 configuration, which sees separation occur for lower diffuser angles and heat flux settings. The separation grows diminishinly as the heat flux and diffuser angle is increased. The separation onset location is found to consistently be in the corners of the outlet diffuser, after which it expands and rotates into the symmetry plane further downstream. The channel 4 solution convergence is found to be increasingly poor for higher diffuser angles, which suggests the solutions may be transient in nature. The Reynolds and Mach number is found to be correlated to the heat flux applied but no conclusion can be made about their link to separation for the cases studied.

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  • 3887.
    Åkerberg, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    CFD analyses of the gas flow inside the vessel of a hot isostatic press2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Hot isostatic pressing (HIP) is a thermal treatment method that is used to consolidate, densify or bondcomponents and materials. Argon gas is commonly used as the pressure medium and is isostaticallyapplied to the material with an excess pressure of 500-2000 bar and a temperature of 500-2200oC. WithHIP treatment being a well-established technology for the last decades, one is now striving to obtain anincreased understanding of local details in the internal gas flow and heat flux inside the HIP apparatus.The main objective of this work is to assess the potential of using computational fluid dynamics (CFD) asa reliable tool for future HIP development. Two simulations are being performed of which the first one isa steady-state analysis of a phase in the HIP-cycle called sustained state. The second simulation is atransient analysis, aiming to describe the cooling phase in the HIP-cycle. The most suitable modelingapproaches are determined through testing and evaluation of methods, models, discretization schemes andother solver parameters. To validate the sustained state simulation, the solution is compared tomeasurements of operating pressure, heat dissipation rate out through the HIP vessel and localtemperature by the vessel wall. However, no validation of the cooling simulations has been conducted. Asensitivity analysis was also performed, from which it could be established that a mesh refinement ofstrong temperature gradients resulted in an increase of wall heat dissipation rate by 1.8%. Both of thesimulation models have shown to yield satisfactory solutions that are consistent with the reality. With theachieved results, CFD has now been introduced into the HIP field and the presented modeling methodsmay serve as guidelines for future simulations.

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    CFD analyses of the gas flow inside the vessel of a hot isostatic press
  • 3888.
    Åkerblom, Signe
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Improving energy performance within the framework of the Energy Efficiency Directive2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is necessary for large companies to understand and be able to adapt to the industrial transformation towards an increasing focus on energy efficiency, which takes place today. The Energy Efficiency Directive (EED)issued by the European Union has enlarged the focus on working with energy efficiency within large companies. Further, the Swedish government has introduced the law about energy auditing in large companies, which is based on the EED. These regulations encourage companies to develop a management system that includes requirements on conducting energy audits and propose cost effective measures.

     Energy efficiency is already an important aspect within many companies environmental work, however a more developed and systematic approach to energy efficiency than most companies already have is needed in order to fulfill the legal requirements. The Company investigated in this study is one the world’s leading technology companies with more than 9000 employees in Sweden. Currently, they have energy as a significant aspect in their environmental work according to the international management system standard ISO 14001. Today they are also developing their energy work by conducting energy audits in order to comply with the new legislation. This gives a more detailed view of the energy use and potential improvements that can be done, but in order to ensure continual improvements over a long period of time further measures are needed.  Within this study it was investigated what measures a large company needs to implement in order to increase their energy performance and comply with the legislation. By a literature review focusing on management systems as well as interviews within the Company, a complementary study with two companies covered by the EED and three expert interviews, five key factors were identified. These factors are top management commitment, awareness, goals, measurements and evaluation. A model was then developed aligning these factors. Further, concrete proposals for action to manage these factors were presented. By increasing focus on these key factors and implement proposed measures companies will increase their energy performance and make the organization aware of how actions affect a company’s energy performance. 

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  • 3889.
    Öhman, Amanda
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lundberg, Linnea
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Maximization of electricity generation or pelletization of the surplus bagasse in a Cuban sugar mill: A comparative analysis2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 3890.
    Öhman, Henrik
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Implementation and evaluation of a low temperature waste heat recovery power cycle using NH 3 in an Organic Rankine Cycle2012In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 48, no 1, p. 227-232Article in journal (Refereed)
    Abstract [en]

    With increasing cost for power generation opportunities for small scale power generation from waste heat have increased. The awareness of untapped resources such as local waste heat streams as well as the available range of technology and products to harvest such streams is increasing steadily though field data is scarce for applications below 100 °C entry temperature. ORC applications have a large number of open parameters and therefore require field data for correlation of models.This paper presents field data and analysis of an ORC power generation plant operating with NH 3. The unit operates on waste heat from a Swedish pulp mill at an available temperature of 75 to 85 °C. Performance at varying heat source conditions and capacity is reported as well as an analysis of the particular investment case.The data was generated during a 15 day period and show a thermal efficiency of 8-9% at capacities from 50 to 100%. The results indicate a flat thermal efficiency from 20 to 100% capacity.Investment case analysis is based on a purchase model while the chosen economic model is a supplier own-and-operate arrangement supplying the mill with power at a predefined cost during an extended period of time.

  • 3891.
    Öhman, Henrik
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Implementation and evaluation of low temperature waste heat recovery power cycle using NH3 in an organic rankine cycle2011In: / [ed] Zvonimir Guzovic, Zagreb: Faculty of Mechanical Engineering and Naval Architecture , 2011Conference paper (Refereed)
    Abstract [en]

    With increasing cost for power generation the opportunities for small scale powergeneration from waste heat have increased. The awareness of untapped resources such aslocal waste heat streams as well as the available range of technology and products toharvest such streams is increasing steadily. For ORC power plant applications the numberof open parameters is large though the reported field data is limited, particularly for lowtemperature waste heat recovery.This paper presents field data and a performance analysis of an ORC powergeneration plant operating with NH3 as media. The ORC unit operates on waste heat froma Swedish pulp mill at an available temperature level of 75 to 85degC. Performance at lowwaste heat temperatures and during capacity variation is reported as well as an analysisof the particular investment case.The field data was generated by remote logging of control system information during a 15day period.The results show a thermal efficiency of 8 to 9% during a capacity range of 50 to 100%power generation. The results indicate a flat thermal efficiency curve from 20 to 100%power generation. The investment case is a supplier own-and-operate type of arrangement supplying thepulp mill with electric power at a predefined cost during a long period of time.

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  • 3892.
    Öhman, Henrik
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Low temperature difference power systems and implications of multi-phase screw expanders in Organic Rankine Cycles2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    New and old data on screw expanders operating with 2-phase mixtures in the admission line has been combined to enable the first public correlation of adiabatic expansion efficiency as a function of entry vapour fraction. Although not yet perfected, these findings have enabled an entirely new approach to the design and optimisation of Organic Rankine Cycles, ORCs. By allowing a continuous variation of vapour fraction at expander entry optima for thermal efficiency, second law efficiency and cost efficiency can be found. Consequently one can also find maxima for power output in the same dimension.

    This research describes a means of adapting cycle characteristics to various heat sources by varying expander inlet conditions from pure liquid expansion, through mixed fluid and saturated gas expansion, to superheated gas. Thermodynamic analysis and comparison of the above optimisations were a challenge. As most terms of merit for power cycles have been developed for high temperature applications they are often simplified by assuming infinite heat sinks. In many cases they also require specific assumptions on e.g. pinch temperatures, saturation conditions, critical temperatures etc, making accurate systematic comparison between cycles difficult. As low temperature power cycles are more sensitive to the ‘finiteness’ of source and sink than those operating with high temperatures, a substantial need arises for an investigation on which term of merit to use.

    Along with an investigation on terms of merit, the definition of high level reversible reference also needed revision. Second law efficiency, in the form of exergy efficiency, turned out to be impractical and of little use. A numerical approach, based on a combination of first and second law, was developed. A theory and method for the above is described. Eventually low temperature power cycle test data was compiled systematically. Despite differences in fluid, cycle, temperature levels and power levels the data correlated well enough to allow for a generalised, rough correlation on which thermal efficiency to expect as a function of utilization of source and sink availability. The correlation on thermal efficiency was used to create a graphical method to pre-estimate key economic factors for low temperature site potential in a very simple manner. A major consequence from the findings of this thesis is the reduced dependency on unique choices of process fluid to match heat source characteristics. This development significantly simplifies industrial standardisation, and thereby potentially improves cost efficiency of commercial ORC power generators.

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  • 3893.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lundqvist, Per
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Comparison and analysis of performance using Low Temperature Power Cycles2013In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 52, no 1, p. 160-169Article in journal (Refereed)
    Abstract [en]

    Low Temperature Power Cycles have become increasingly interesting means of increasing energy efficiency of processes as well as for base load power generation from solar, and geothermal, heat. Theoretical understanding of the various processes, components and limitations is constantly increasing through extensive research. Practical utilisation of this knowledge is also increasing steadily though properly published field data is scarce. In this article a number of different solutions for power generation from low temperature heat sources have been gathered and analysed. Some of the studied units have not previously been described. A method for general evaluation of LTPC's is proposed and the outcome of the analysis is discussed as well as how to use it for practical purposes. By separating thermodynamic potential from irreversibilities the analysis indicates that the irreversibilities show limited dependency on temperature, size, thermodynamic cycle or working fluid. Instead performance of the studied units follows a relatively simple correlation with utilisation of the thermal potential. This correlation is defined and discussed. One conclusion is that the correlation allows for a possibility to express the maximum expected real power generation with knowledge of the characteristics of the heat source and heat sink only.

  • 3894.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lundqvist, Per
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Experimental investigation of a Lysholm Turbine operating with superheated, saturated and 2-phase inlet conditions2013In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 50, no 1, p. 1211-1218Article in journal (Refereed)
    Abstract [en]

    Low temperature power cycles can benefit from the use of multi-phase flow expansion devices from a thermodynamic cycle efficiency point of view. Particularly power cycles such as ORC, Kalina and Trilateral Flash Cycles can be improved by multi-phase expansion. This article presents the experimental findings in a series of laboratory tests on a semihermetic Lysholm Turbine operating with R134a with superheated, saturated and wet inlet gas conditions. The test arrangements are described as well as discussion on the relevance of such test data. Finally comparison is made with findings from other investigations and recommendations for further studies are made. A correlation between peak efficiency and sensitivity to inlet vapour fraction was discovered which allows for estimations of adiabatic efficiencies with 2-phase inlet conditions even when only test data, or simulations, from single phase inlet conditions exist. The conclusions made are that Lysholm Turbines are well suited for low temperature power generation and that further understanding of the performance during 2-phase conditions is required.

  • 3895.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lundqvist, Per
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    On high level evaluation and comparison of ORC power generators2015In: Proceedings of the 3rd International Seminar on ORC Power Systems, 2015Conference paper (Refereed)
    Abstract [en]

    A review of the thermodynamic performance of ORCs from public, as well as non-public sources hasrevealed a correlation suitable to be used as a rule of thumb for  high-level performance estimation ofORC power generators. Using the correlation, the limited amount of available test data can begeneralised leading to a high level evaluation of the commercial benefits of any potential applicationfor ORCs.Power generators using ORC-technology exist in relatively low numbers. Furthermore, fieldinstallations seldom imply comparable boundary conditions. As ORCs generally  operate at lowtemperature differences between source and sink it has been shown that their relative sensitivity tovariations in temperatures i.e. the finiteness of source- and sink, is larger than the sensitivity of powergenerators operating with large temperature differences. Therefore the establishing of practical rule ofthumb performance estimation, similar to the figure of merit, Coefficient of Performance, COP, asused in refrigeration and air conditioning industry, has previously not been successful.In order to arrange field data in a manner suitable for comparison a refinement of suitable figures ofmerit was required. The suggested, refined terms are presented and explained as well as criticallyevaluated against the most common  efficiency terms traditionally used.The current lack of a performance rule of thumb leaves room for less serious vendors and laymen tomake performance claims unrealistic to practical achievements. Scrutinizing such questionablestatements requires detail process simulations and a multitude of technical assumptions. Henceargumentation becomes ineffective. If a suitable rule of thumb can be established argumentationagainst dubious claims would become significantly more forceful.This paper suggests a new term to be used as rule of thumb and explains a  method on how to use it.

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  • 3896.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lundqvist, Per
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Screw expanders in ORC applications, review and a new perspective2015In: Proceedings of the 3rd International Seminar on ORC Power Systems, 2015Conference paper (Refereed)
    Abstract [en]

    Performance of Organic Rankine Cycles is sensitive not only to the entry  temperature ratio betweenheat source and heat sink but also to the temperature  degradation of the heat source flow, caused bythe heat transfer to the process in pre-heater, evaporator and super heater. In order to adopt the cycleto the great variety of heat sources a multitude of fluids are required. Alternatively fluid mixtures,trans-critical or supercritical fluid conditions can be used to match the process temperatures with theheat source. Screw expanders offer an alternative, new approach to the matching problem of ORC’s asthey allow for flexible multi-phase expansion. Hereby the vapour fraction at the expander entry can beused to  partially match the temperatures of the process to a particular heat source. To provide aperspective on the use of such screw expanders in ORC-systems previous experimental andcommercial experience have been reviewed and discussed.Screw expanders are versatile machines used for the production of mechanical work in power rangesfrom 3kW to 1.5MW. As the functional characteristics differ significantly  from dynamic expandersthe explanatory models used to generalise results are different. Plenty of research has resulted in wellgeneralized explanatory models for dynamic expander analysis. For screw expanders similarexplanatory models exist mainly in commercially confidential environments. A few public sourcesdisclose test data. In the few cases data has been investigated the analyses tend to rely onthermodynamic models suitable for dry gas expansion. Typically that leads to reasonable replicationof test results but seldom to models suitable for detailed understanding of the process. In applicationswith 2-phase expansion the theories used to simulate functional characteristics is entirely insufficient.The main reason for  the scarcity of work in this field is probably the empirical difficulties in obtaininggood measuring data in multi-phase conditions.This paper describes a review of multi-phase screw expander experiences and explains why a uniquetheory is required to model its characteristics. In the absence of such a unique theory a correlationbased in empirical data is presented. This allow for estimations of screw expander efficiency in multi-phase conditions. Measured efficiency with dry expansion, or such efficiency simulated, can be usedto estimate adiabatic efficiency with expansion entry vapor fractions ranging from 0 to 1 by using thiscorrelation. Hence estimating expansion efficiency during multi-phase expansion is simplified,allowing for better optimisation of the ORC-systems. This way a new perspective of screw expanderpotential in ORC system integration can be presented.

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  • 3897.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lundqvist, Per
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Theory and method for analysis of low temperature driven power cycles2012In: Applied Thermal Engineering, ISSN 1359-4311, no 37, p. 44-50Article in journal (Refereed)
    Abstract [en]

    A new method, using a combination of traditional first law and second law analysis, is developed to facilitate characterization and comparison of power cycles using low temperature heat sources. In trying to determine the best thermodynamic cycle and working media for a given application one must take the strongly non-linear effects of matching the pinch points of a particular cycle with a particular working media into account. The new method allows unbiased comparison of arbitrarily chosen power cycles, working fluids and component characteristics. The method also allows for operating conditions with finite capacity heat source and heat sink. The usefulness of the method is illustrated by the analysis of the effects of local temperature difference distribution for three different fully reversible power cycles using three different working media.

    The driver for developing this method is to simplify comparison and communication among users and industrial professionals and thus enable a better understanding of characteristics and design criteria for low temperature heat driven power cycles.

  • 3898.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Per, Lundqvist
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Organic Rankine Cycles with variable vapour fraction expansion entry: Reduced sensitivity to choice of working fluid in modified Organic Rankine Cycles by using wet vapour expansion entry conditions2014Report (Other academic)
    Abstract [en]

    The task of reducing global carbon dioxide emissions leads to a need to reduce the average CO2-emission in power generation. A more energy efficient mix of power generation on national, or regional level, will require the re-use of waste heat and use of primary, low temperature heat for power generation purposes. Low Temperature Power Cycles, such as Organic Rankine Cycles, Trilateral Flash Cycles, Kalina Cycles offer a large degree of freedom in finding technical solutions for such power generation.

    Theoretical understanding of LTPC’s advance rapidly though practical achievements in the field show very humble improvements at a first glance. Cost of applying the new knowledge in real applications seems to be an important reason for the discrepancy. One central reason for the high cost level is the diversity of process fluids required and consequently the lack of standardization and industrialization of equipment. Uses of supercritical power cycle technology tend to cause the same dilemma. Furthermore upcoming regulations prohibiting the use of several process fluids tend to lead to remedies increasing plant cost.

    By using 2-phase, variable vapour fraction, expansion inlet conditions the need to use many different process fluids is reduced, allowing simpler and more cost efficient LTPC’s by easier matching with heat source temperature characteristics. This article explores some of the associated effects on cycle output and cost efficiency. A waste heat recovery application is investigated simulating cost efficiency, thermodynamic efficiencies and power generation while using fundamentally different working fluids, lumped component efficiencies, variable utilization of the waste heat and optimisation on expansion inlet vapour fraction.

    The conclusion made is that the sensitivity to choice of working fluid is lower than intuitively anticipated, in contrast to common consensus in science. Furthermore it is shown that exceptional component efficiencies are not required in order to achieve a performance comparable to current practise and that a good business case is possible under the assumed economic conditions.

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  • 3899.
    Öhman, Henrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Per, Lundqvist
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Thermodynamic pre-determination of power generation potential in geothermal low-temperature applications2014In: Geothermal Energy, E-ISSN 2195-9706, Vol. 2, no 1, p. 1-10, article id 4Article in journal (Refereed)
    Abstract [en]

    Background: Small capacity, low temperature, geothermal heat sources providesignificant opportunities for distributed, small scale power generation. Projectdefinitions and pre-dimensioning however require advanced thermodynamicengineering at a cost independent of project size. In order to reduce this cost, anew method has been developed to allow basic level engineers to performpre-optimisation of thermodynamic potential as well as expected performance usingavailable power plant technology at such pre-optimized conditions.Results: By reducing the complexity of second-law computations, a simpletwo-dimensional diagram is shown representing the dimensioning criteria requiredfor maximum power generation using the particular heat source and sink whileconsidering expected power plant performance, using systems and componentson the market.Methods: By sensitivity analysis the combination of thermodynamic analysis and realworld data correlations was simplified and arranged for pre-dimensioning ofbusiness cases.Conclusions: Optimal pre-dimensioning of power generation system for anygeothermal heat source, with a defined heat sink, can be determined withoutadvanced thermodynamic expertise. This reduces the cost for business case proposals,pre-dimensioning and tender specifications of small-scale power generation systemsfor low temperature heat sources. The intended implication of this work is to increasethe use of low-temperature geothermal wells for distributed power generation.

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  • 3900.
    Öncel, Melih
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology. KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Marion, Gonzalo
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology. KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS. Universitat Politecnica de Catalunya.
    Providing Sustainable Life-solutions with a Hybrid Micro-Power Plant in Developing Countries: an Assessment of Potential Applications2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today, energy access is a significant challenge all over the world, particularly in African countries. At the same time, providing energy access is generally accepted as a way to promote sustainable development. In countries such as Uganda, lack of energy access is evident. In this country only 9% of households have access to electricity. About 87% of these households are located in rural and remote areas. Thus, off-grid rural electrification solutions are required to supply electricity services to a significant part of the population.The ultimate objective of this thesis is to propose a specific solution to cover basic energy needs of the rural population considering environmental, social and economic benefits. How can sustainable life solutions be provided in rural areas, by using the energy surplus from a decentralized small-scale biomass gasification power plant? The analysis used as a starting point the Green Plant Concept, which considers the design of a sustainable off-grid platform that produces energy to provide life solutions and also to excite local entrepreneurship in the rural sites where it is implemented. The concept implies participation of the private sector – a telecommunication company – which is a unique feature in the context of rural energization.To develop our analysis, a field trip has been conducted in Uganda, Africa, to answer sub-questions such as How to reach a cost-effective system? How to adapt a business oriented approach to the community’s life-style in order to be well accepted? How to foster the development of the area by having a positive socio-economic impact on society? How to create an environmental friendly solution? How to achieve the maximum efficiency in terms of reusing waste? Tools such as Multi Criteria Analysis (MCA) and SWOT analysis were used to interpret collected information and identify impacts of the suggested solutions.The research has shown the great potential of the Green Plan Concept. We conclude by selecting three applications that can enhance the provision of basic energy needs while creating benefits for the stakeholders involved in the process: i) Mini-Grid solutions, ii) Battery Charging Stations and iii) Heat Pipe Exchangers. We also highlighted the relevance of bringing, in addition to appropriated technologies, different stakeholders together, considering their common interests.The research is finalized by estimating the payback period based on the current and expected energy consumption and the capital investment related to the suggested applications. It is important to highlight that the payback time estimations do not include the participation of the telecom companies. This means that the estimated payback period of 7 years could be significantly reduced by the inclusion of this stakeholder.

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