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  • 301.
    Baagherzadeh Hushmandi, Narmin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Effects of multiblocking and axial gap distance on performance of partial admission turbines: A numerical analysis2011In: Journal of turbomachinery, ISSN 0889-504X, E-ISSN 1528-8900, Vol. 133, no 3, p. 031028-Article in journal (Refereed)
    Abstract [en]

    In this paper, the effects of axial gap distance between the first stage stator and rotor blades and multiblocking on aerodynamics and performance of partial admission turbines are analyzed numerically. The selected test case is a two stage axial steam turbine with low reaction blades operating with compressed air. The multiblocking effect is studied by blocking the inlet annulus of the turbine in a single arc and in two opposing blocked arcs, each having the same admission degree. The effect of axial gap distance between the first stage stator and rotor blades is studied while varying the axial gap by 20% compared with the design gap distance. Finally, full admission turbine is modeled numerically for comparison. Performance of various computational cases showed that the first stage efficiency of the two stage partial admission turbine with double blockage was better than that of the single blockage turbine; however, the extra mixing losses of the double blockage turbine caused the efficiency to deteriorate in the downstream stage. It was shown that the two stage partial admission turbine with smaller axial gap than the design value had better efficiency of the first stage due to lower main flow and leakage flow interactions; however, the efficiency at the second stage decreased faster compared with the other cases. Numerical computations showed that the parameters, which increased the axial force of the first stage rotor wheel for the partial admission turbine, were longer blocked arc, single blocked arc, and reduced axial gap distance between the first stage stator and rotor blades.

  • 302.
    Baagherzadeh Hushmandi, Narmin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fridh, JensKTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.Fransson, TorstenKTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Unsteady Forces of Rotor Blades in Full and Partial Admission Turbines2010Conference proceedings (editor) (Refereed)
    Abstract [en]

    A Numerical and experimental study of partial admission in a low reaction two-stage axial air test turbine is performed in this paper. In order to model one part load configuration, corresponding to zero flow in one of the admission arcs, the inlet was blocked at one segmental arc, at the leading edge of the first stage guide vanes. Because of the unsymmetrical geometry, the full annulus of the turbine was modeled numerically. The computational domain contained the shroud and disc cavities. The full admission turbine configuration was also modeled for reference comparisons. Computed unsteady forces of the first stage rotor blades showed cyclic change both in magnitude and direction while moving around the circumference. Unsteady forces of first stage rotor blades were plotted in frequency domain using Fourier analysis. The largest amplitudes caused by partial admission were at first and second multiples of rotational frequency due to the existence of single blockage and change in the force direction. Unsteady forces of rotating blades in a partial admission turbine could cause unexpected failures in operation; therefore knowledge about the frequency content of the unsteady force vector and the related amplitudes is vital in the design process of partial admission turbine blades. Pressure plots showed that the non-uniformity in the static pressure field decrease considerably downstream the second stage stator row, while the non-uniformity in the dynamic pressure field is still large. Numerical results between the first stage stator and rotor rows showed that the leakage flow leave the blade path down to the disc cavity in the admitted channel and re-enter into the main flow in the blocked channel. This process compensate the sudden pressure drop downstream the blockage but reduce the momentum of the main flow.

  • 303.
    Baagherzadeh Hushmandi, Narmin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fridh, Jens
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Unsteady Forces of Rotor Blades in Full and Partial Admission Turbines2011In: Journal of turbomachinery, ISSN 0889-504X, E-ISSN 1528-8900, Vol. 133, no 4, p. 041017-1-041017-12Article in journal (Refereed)
    Abstract [en]

    A numerical and experimental study of partial admission in a low reaction two-stage axial air test turbine is performed in this paper. In order to model one part load configuration, corresponding to zero flow in one of the admission arcs, the inlet was blocked at one segmental arc, at the leading edge of the first stage guide vanes. Due to the unsymmetrical geometry, the full annulus of the turbine was modeled numerically. The computational domain contained the shroud and disk cavities. The full admission turbine configuration was also modeled for reference comparisons. Computed unsteady forces of the first stage rotor blades showed cyclic change both in magnitude and direction while moving around the circumference. Unsteady forces of first stage rotor blades were plotted in the frequency domain using Fourier analysis. The largest amplitudes caused by partial admission were at first and second multiples of rotational frequency due to the existence of single blockage and change in the force direction. Unsteady forces of rotating blades in a partial admission turbine could cause unexpected failures in operation; therefore, knowledge about the frequency content of the unsteady force vector and the related amplitudes is vital to the design process of partial admission turbine blades. The pressure plots showed that the nonuniformity in the static pressure field decreases considerably downstream of the second stage's stator row, while the nonuniformity in the dynamic pressure field is still large. The numerical results between the first stage's stator and rotor rows showed that the leakage flow leaves the blade path down into the disk cavity in the admitted sector and re-enters downstream of the blocked channel. This process compensates for the sudden pressure drop downstream of the blockage but reduces the momentum of the main flow.

  • 304.
    Baagherzadeh Hushmandi, Narmin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Hu, Jiasen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fridh, Jens
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Numerical investigation of partial admission phenomena at midspan of an axial steam turbine2007In: Proceedings of the 7th European Conference on Turbomachinery: Fluid Dynamics and Thermodynamics, ETC 2007, European Conference on Turbomachinery (ETC) , 2007Conference paper (Refereed)
    Abstract [en]

    This paper presents unsteady Navier-Stokes analysis to investigate partial admission phenomena in an axial two-stage steam turbine. The computations are performed in two-dimensional flow conditions at the midspan of the turbine with CFD software Fluent. Unlike some previous numerical work published in open literature, the partial admission in the present study is introduced into the model by blocking only one segmental arc (85.7°) of the guide vanes at the first stage. It is therefore necessary to model the whole annulus of the turbine in the numerical simulations. Results of the analysis show that the peak static pressure drop occurs downstream of the blockage at the entrance to the blocked region where emptying of the rotor channel occurs. The first stage rotor blades experience large static pressure changes on their surfaces and large tangential and axial forces. The magnitude of the tangential and axial forces is twice as large at the entrance to the cavity behind the blockage than at the exit of the blocked region. Entropy concentration downstream of the blockage is considerably high due to the nonuniformities in the flow field. The present results show good agreement between experiments and computations, in tendency of the circumferential static pressure at different axial cross sections. The difference between the numerical and experimental absolute values of the circumferential static pressure drop in the blocked region indicates that the three-dimensional effects are very important to the flow field behind the blockage.

  • 305.
    Baagherzadeh Hushmandi, Narmin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Hu, Jiasen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fridh, Jens
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Numerical Investigation of Partial Admission Phenomena at Midspan of an Axial SteamTurbine2007In: Proceedings of 7th European Conference on Turbomachinery,Fluid Dynamics and Thermodynamics, 2007Conference paper (Refereed)
  • 306.
    Baagherzadeh Hushmandi, Narmin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Hu, Jiasen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fridh, Jens
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Numerical Study of Unsteady Flow Phenomena in a Partial Admission Axial Steam Turbine2008In: Proceedings of ASME Turbo EXPO 2008, New York: AMER SOC MECHANICAL ENGINEERS , 2008, p. 713-722Conference paper (Refereed)
    Abstract [en]

    This paper presents a numerical investigation of unsteady flow phenomena in a two-stage partial admission axial steam turbine. Results from unsteady three-dimensional computations are analyzed and compared with the available experimental data. Partial admission in the present study is introduced into the model by blocking only one segmental arc of the inlet guide vanes. Blocking only one segment (which corresponds to the experimental setup) makes the model unsymmetrical; therefore it is necessary to model the whole annulus of the turbine. The first stage rotor blades experience large static pressure change on their surface while passing the blocked channel. The effect of blockage on the rotor blades' surface pressure can be seen few passages around the blocked channel. Strong changes of the blades' surface pressure impose large unsteady forces on the blades of first stage rotor row.

    The circumferential static pressure plots at different cross sections along the domain indicate how the non-uniformity propagates in the domain. A peak pressure drop is seen at the cross section downstream of the first stage stator row. At further downstream cross sections, the static pressure becomes more evenly distributed. Entropy generation is higher behind the blockage due to the strong mixing and other loss mechanisms involved with partial admission. Analysis of the entropy plots at different cross sections indicates that the peak entropy moves in a tangential direction while traveling to the downstream stages. Comparisons of the unsteady three-dimensional numerical results and the experimental measurement data show good agreement in tendency. However some differences are seen in the absolute values especially behind the blockage.

  • 307.
    Baaklini, Daniel
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Performance analysis of Air GapMembrane Distillation:Comparison of PTFE membranes: Comparison of PTFE membranes2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Membrane Distillation (MD) is a very promising new technology which can be coupled with renewableenergies and/or waste heat to produce pure water at a low-cost. MD is extremely dependent upon theperformance of the membrane, as it dictates the mass transfer, the heat transfer and the long-termapplication. Unfortunately, there are no commercially produced MD-specific membranes at this point intime. This project aims at finding correlations between membrane characteristics and their performancesin order to define the optimal morphologies and operating conditions for a MD-specific membrane. Todo so, the characteristics of 3 PTFE membranes initially designed for MF were determined throughporosity measurements and microscopic imaging, while their performances were evaluated by measuringthe air permeability and by testing them on an AGMD bench-scale unit.It was found that the most desirable characteristics for a membrane with a high flux are a film with largeporosity, low tortuosity, a small thickness with a resistance to compaction and that has not been subjectedto thickness altering processes. Moreover, the surface pore sizes need to be small enough to avoid surfacewetting, and the backing layer should not restrict the vapor flow in a significant way and should possesslarge open areas.As the feed water temperature and/or the flow rate rises, the flux increases and the energy requirementdecreases, this means that one should ideally aim for the highest possible operating conditions whichrequires larger costs. Therefore it is necessary to find a cost effective solution for each application.The results show that, for comparative purposes, Gurley values are good indicators of a membrane’soverall performance in MD, despite the fact that it does not always accurately predict it. It has also beenfound that membrane specifications provided by manufacturers are generally only approximations, andshould therefore not be used as very precise data for comparing membranes.

    Download full text (pdf)
    Master Thesis Report _ Daniel BAAKLINI
  • 308.
    Back, Izabelle
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Dunberger, Lars
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Evaluating alternative refrigerants for the room air conditioner market2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study aimed to facilitate evaluation of alternative refrigerants for the air conditioner market. In order to achieve this target, two objectives were set. The first being the identification of alternative refrigerant with regard to regulations and trends. The second being enabling of thermodynamic evaluation of refrigerants for single components in air conditioners via design and installation of a test rig. A literature review was conducted to investigate the regulations, standards and trends for nine regions with high market shares. Furthermore, refrigerant substitutes for R410A and R22 where identified. The literature showed strong indications that a global HFC phase down is on the horizon, but that the approach and urge for such a phase down varies between regions where three main priorities could be seen; efficiency, GWP values and safety. Comparing these priorities with simulated refrigerant characteristics such as Carnot efficiency, GWP values, volumetric capacity and the liquid density using RefProp, identified alternatives. Further the literature showed that the lower flammability limit (LFL) and the amount of charge allowed were limiting factors for flammable refrigerant. There are many new refrigerants that could have less charge for the same capacity the LFL however restricts the refrigerants like R290, R441A and R443A only to be used in small systems. A test rig was designed and constructed in order to enable testing of single components in air conditioners. To verify the test rig, tests conducted with an evaporator using two refrigerants: R410A and R32. The reliability and validity of the tests was studied by comparing the results from the air side and refrigerant side, via uncertainty calculations using the GUM method and by a thermodynamic evaluation. The results of the repetition tests showed an expanded uncertainty, with a confidence interval of 95%, of 26 W for a cooling capacity of 2190W for R410A (Q̇evap,R410A=2190±26W). For R32 the expanded uncertainty was 27W for a cooling capacity of 2795W (Q̇evap,R32=2795±27W). Also the test rig was verified to be used for analyzing detailed evaluation of evaporators such as looking at heat transfer and the differential pressure drop. Further the study presented six conclusions:

    • When evaluating refrigerants regional priorities between efficiency, safety and GWP values, refrigerant characteristics and type of unit need to be considered.
    • Safety standards need to be more acceptable towards flammable refrigerants in order to meet low GWP targets.
    • The change in market trends leads to new roles for the refrigerant and compressor suppliers and put higher demand on air conditioner manufacturers to consider refrigerant characteristics in product development.
    • The importance of experimental thermodynamic evaluation on refrigerants effect on single components is increasing.
    • Performance of different refrigerant for single components can be evaluated for optimizing cycle performance.
    • Leapfrogging in the developing world can lead to a faster introduction of low GWP refrigerants. 

    Download full text (pdf)
    fulltext
  • 309.
    Backlund, Lisa
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Carter, Sabrina
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Effective Utilisation of Oil PalmWaste as Renewable Energy: A Comparative Study of Residue Pellets and Residue Usage forElectricity Delivery to Grid2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Palm oil is currently the leading player in the global oil trade market. The industry is large and stillconstantly growing, and includes not just potential benefits in terms of an increasing amount ofpalm oil produced, but also advantages in regards to potential utilisation of palm oil residues. Thepalm oil industry produces a large amount of biomass from the production of the oil, whichcould, with the right technology and right financial resources, be converted into sustainablerenewable energy that could provide to the international demand.This thesis aims to investigate the profit potential of selected types of conversion of waste intobioenergy for leading palm oil producers such as Indonesia and Malaysia, and further analyse thecurrent market and sources of financial resources. The study covers the two scenarios regardingboth the generation and supply of electricity to the domestic grid, and to produce palm wastepellets.The result illustrates that when waste is utilised in electricity generation and supplied to the grid itwill be more profitable than when producing pellets. A main reason for this is that the waste hasthe potential of generating a large amount of electricity; this is further compounded by the factthat it can be sold at a premium rate provided by the government. However, the production ofpellets does have potential benefits as well. Most importantly is the smaller initial cost, whichmakes it appealing for smaller actors. Also, because of a growing pellet demand in Europe andworldwide, a lot can happen in the market place for palm waste pellets.The initiatives from the government, which support renewable energy sources and privateinvestors, are essential to the funding of these projects, which in turn makes the palm wasteindustry profitable. The governments of these countries involved are beginning to realise theirmajor roles and the importance that the implementations of their financial support plays. It isgiven these factors that the utilisation of palm waste as a renewable energy has the potential ofbeing an important and successful industry in the future.

  • 310.
    Backman, Peter
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Commercialization possibilities of Stirling engine technology for microscale power generation in Sweden2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The presented master’s thesis has evaluated the possibility of commercializing a research project at the Royal Institute of Technologys (KTH) Department of Energy Technology (EGI) in Stockholm, Sweden, where a Stirling engine is used for renewable microscale power generation.  The purpose of the thesis has been to evaluate the current market situation and future prospects by composing a business plan under the working name MicroStirling.

    In the business plan a potential target group consisting of house owners, farming companies and small energy-intensive industries has been identified. The market is currently small but displaying tremendous possibilities and is likely to grow rapidly in coming years. By offering a unique, high quality product MicroStirling has a competitive edge; however, several risks threaten the success of the company. Market readiness and customer acceptance of the technology are significant market barriers.

    Short term focus should be concentrated on technology development to prepare for pilot projects in 2013 and a market introduction in 2014. A future successful commercialisation of the technology is viable although further technical and business development is required to finalize a product ready for a market introduction. 

    Download full text (pdf)
    fulltext
  • 311.
    Badran, Bassam E.
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Mota-Babiloni, Adrian
    Univ Jaume 1, Dept Mech Engn & Construct, Castellon de La Plana 12071, Spain..
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Theoretical Study of a Multilevel Heat Pump for Multi-Source Heating2021In: 6Th Iir Conference On Thermophysical Properties And Transfer Processes Of Refrigerants (Tptpr2021), INT INST REFRIGERATION , 2021, p. 243-250Conference paper (Refereed)
    Abstract [en]

    Industry and other sectors are currently looking for solutions to decarbonize their processes, including heating, which is mainly based on fossil fuel boilers. Heat pumps can provide heating with higher performance based on their high coefficient of performance (COP). This work considers a multilevel heat pump (MTHP) for multi-source heating, based on a three-stage cascade in which excess heat in the condenser is used for external flows, that can be connected in series or parallel. Several available low GWP refrigerants have been considered, and a multi-parameter selection analysis has been carried out. For low, medium, and high-temperature stages, R1243zf, R-1224yd(Z), and R-1233zd(E) are the best refrigerants, respectively, selected. This system is able to operate between 0 and 160 degrees C, with three heating levels at 60, 110, 160 degrees C (31.75, 21.59, and 29.92 kW, respectively) at a COP of 2.181. The total cooling capacity of the system is 45.08 kW and the total heating capacity is 83.26 kW. The MTHP concept can provide a significant carbon footprint reduction compared to natural gas boilers used in European countries.

  • 312.
    Baeza Zamora, Alejandro
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    A Zero Energy House for UAE2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A zero energy house for the hot and humid climate of UAE is designed. It is focused on improve the building envelope through insulation materials, low density concrete, reflective coatings and low SHGC windows. The design is done by computer simulations using TRNSYS and POLYSUN software. Passive technologies are able to reduce the cooling load to 80%, which represents a 55% reduction of the total electricity consumption in the original building. Adding active technologies such as high efficient air conditioning chiller and solar water heater, total electricity consumption of the house is reduced to 70%. The remaining cooling load is covered by 6.5 kW PV system which is placed on the available roof area.

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    fulltext
  • 313.
    Bahram, Saadatfar
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fransson, Torsten
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Reza, Fakhrai
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    EXERGOECONOMIC ANALYSIS of a NANO FLUID ORC COGENERATION of LOW-GRADEWASTE2013Conference paper (Refereed)
  • 314.
    Bahram, Saadatfar
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Reza, Fakhrai
    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.
    Thermodynamic Vapor Cycles for Converting Lowto Medium-grade Heat to Power: A State-of-theart Review and Future Research Pathways2014In: The Journal of MacroTrends in Energy and Sustainability, ISSN 2333-0511, Vol. 2, no 1, p. 1-25Article in journal (Refereed)
  • 315.
    Bahram, Saadatfar
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Reza, Fakhrai
    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.
    Waste heat recovery Organic Rankine cycles in sustainable energy conversion: A state-of-the-art review2013In: The Journal of MacroTrends in Energy and Sustainability, ISSN 2333-0511, Vol. 1, no 1, p. 161-188Article in journal (Refereed)
  • 316.
    Bahta, Solomon Teklemichael
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Design and Analyzing of an Off-Grid Hybrid Renewable Energy System to Supply Electricity for Rural Areas: Case Study: Atsbi District, North Ethiopia2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    Master Thesis
  • 317.
    Baillet, Claire
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Conception of an electric bus line simulation tool: Development of a tool allowing for the design of electric bus lines charging infrastructures at INGEROP2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    See file

    Download full text (pdf)
    fulltext
  • 318.
    Baina, Fabiola
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Universidad Mayor de San Simón (UMSS), Bolivia .
    Malmquist, Anders
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Alejo, Lucio
    Fransson, Torsten H.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Effect of the fuel type on the performance of an externally fired micro gas turbine cycle2015In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 87, p. 150-160Article in journal (Refereed)
    Abstract [en]

    Externally fired gas turbines open the possibility of using fuels of lower quality than conventional gas turbines and internal combustion engines. This is because in externally fired gas turbines, the flue gases heat the compressed air in a high temperature heat exchanger. This heat exchanger can more easily deal with contaminants present in the flue gases. In this regard, the configuration of externally fired gas turbines represents an interesting option for biomass gasification gas. The contaminants and low heating value (LHV) of this fuel have made it difficult to find a conversion technology for heat and power generation. For this reason, it is important to study the influence of biomass derived gas as fuel on the performance of this system and consider the effects of the contaminants in the high temperature heat exchanger. This is studied in this work through simulations using Aspen Plus and Matlab. The test data of an externally fired micro gas turbine prototype was used to validate the simulation. The fuel considered was biomass gasification gas with varying concentrations of benzene 100, 10 and 1 g/Nm3 (hereafter named m100, m10, and m1 respectively). Additionally, mixtures of biomass derived gas and methane were studied for 10 and 50% of the thermal power of the combustor. The fuel inlet temperature to the combustor varied from 150 °C to 750 °C in order to represent the fuel gas after removal of particles by a cyclone and a filter. The results showed that the electrical power output increases when high fuel inlet temperatures to the combustor are used. Additionally, although it would be expected that fuels with higher LHV (lower heating value) show higher temperatures and higher output power, this does not always occur because of the composition of the fuels and their respective flue gas temperatures. The addition of methane does not have a large effect on the electrical power output. For a fixed temperature limit in the heat exchanger, the composition of the fuels does not play an important role. However, high fuel inlet temperatures to the combustor show slightly higher efficiencies. Additionally, the effect on the electrical power output of increasing the pressure drop as a result of increased thickness of deposit materials in the heat exchanger was analyzed.

  • 319.
    Baina, Fabiola
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Malmquist, Anders
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Alejo, Lucio
    Fransson, Torsten H.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Extended operability of a commercial air-staged burner using a synthetic mixture of biomass derived gas for application in an externally fired micro gas turbine2015In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 150, p. 664-671Article in journal (Refereed)
    Abstract [en]

    Biomass gasification converts solid biomass into a gaseous fuel that is more versatile and can be used in many applications. However, biomass gasification gas contains some contaminants and inert compounds. The contaminants can cause several problems in the downstream equipment and undesirable emissions while the inert compounds can affect the lower heating value of the gas. Because of these characteristics, there have been difficulties in finding a conversion technology using biomass gasification gas for heat and power generation. In this regard, externally fired gas turbines open a possibility for this combustible gas since due to its configuration, combustion takes place outside the conventional gas turbine cycle. For this reason, combustion studies of biomass derived gas are important. In this work the operability of a commercial air-staged natural gas burner is shown in terms of CO, UHC, and NOX emissions using a synthetic mixture of biomass gasification gas. Two fuel gas mixtures simulating the composition of biomass gasification gas are injected in the combustor. Each fuel gas contains different injection rates of benzene in order to represent tars and to understand their effect on the combustion performance. Additionally, the equivalence ratio is varied in a range of lean conditions in order to find an optimum operation point for the burner studied. The results showed that the presence of polyaromatic hydrocarbons such as benzene reduced the CO concentrations in the exhaust gas while it increased the concentrations of unburned hydrocarbons (UHC) at equivalence ratios lower than 0.68. Additionally, NOX emissions showed a relatively constant trend over the range of equivalence ratios studied for both fuels. It was also observed that NOX emissions increase with the addition of benzene in the fuel gas. An optimum point with regards CO and UHC concentrations was found for the fuels tested.

  • 320.
    Baina, Fabiola
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Universidad Mayor de San Siḿona, Bolivia .
    Malmquist, Anders
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Alejo, Lucio
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Fransson, Torsten H.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Analysis of a high-temperature heat exchanger for an externally-fired micro gas turbine2015In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 75, p. 410-420Article in journal (Refereed)
    Abstract [en]

    The externally-fired gas turbine (EFGT) can convert fuels such as coal, biomass, biomass gasification gas and solar energy into electricity and heat. The combination of this technology with biomass gasification gas represents an interesting option for gasification, for which it has been difficult to find a conversion technology. In this system, the heat exchanger deals with the contaminants of biomass derived gas instead of the turbine itself. However, these contaminants can build a deposit layer in the heat exchanger that can affect its performance. The heat exchanger is important in externally fired gas turbines since the turbine inlet temperature is directly dependent on its performance. Several studies on heat exchangers for externally fired gas turbines have been carried out. However, very few detailed studies were found comparing the performance of heat exchangers for externally fired gas turbines considering the effect of deposit materials on the surfaces. In this regard, this work compares the performance of a corrugated plate heat exchanger and a two-tube-passes shell and tube heat exchanger considering the effect of thickness of deposit material with different thermal conductivities on pressure drop and effectiveness. The results show that the effectiveness of the corrugated plate heat exchanger is more influenced at larger thicknesses of deposit materials than the two-tube-passes shell and tube heat exchanger. There is an exponential increase in the pressure drop of the plate heat exchanger while a monotonic increase of pressure drop is seen for the shell and tube heat exchanger. The increase in the thickness of the deposit material has two effects. On one hand, it increases the resistance to heat transfer and on the other hand, it reduces the through flow area increasing the velocity and hence the heat transfer coefficient. Additionally, the effectiveness of the heat exchangers had a stronger influence on the power output than the pressure drop.

  • 321.
    Baina Veizaga, Fabiola
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Externally fired gas turbine cycle based on biomass gasification gas as fuel2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energy services are essential for the development of societies, reduce poverty, and improve the living standards of inhabitants. The conventional routes to provide energy services employ fossil fuels. However, this involves environmental and availability concerns. Environmental issues and the need for energy security demand the use of alternative energy sources. Biomass is a renewable energy source that is advantageous because of its dispatchability and local availability worldwide. Local generation at small scales is interesting because it reduces energy losses when transporting electricity and heat. The development of sustainable decentralized small scale heat and power plants (CHP) using biomass is thus important.

    In this context, this work is mainly focused on the development of an energy conversion technology based on an externally fired gas turbine using biomass gasification gas as fuel. Although this system is not new, its applicability with biomass gasification gas has not been widely studied. This work is divided in three parts. In the first part, the effect of the fuel composition and fuel inlet temperature on the performance of an externally fired gas turbine prototype is analyzed through simulations. Then, the performances of two types of heat exchangers are compared under the operational conditions of the prototype taking into account different thicknesses of deposit materials. The results shows that the composition of the fuels and the corresponding flue gas temperatures affect the electrical power output of the system. However, this is limited by the operating temperature of the heat exchanger. It is also reported that a decrease in the effectiveness of the heat exchanger has a greater influence on the electrical power output than an increase in the pressure drop as a result of deposit materials. High pressure drops in the hot side of the heat exchanger slightly affect the electrical power output. If biomass gasification gas is to be used after the gasifier with reduced cleaning steps, the effect of contaminants such as tar in the combustion performance is important. The last part in this work describes experimental studies of the effect of benzene as tar representative in the combustion performance of a surrogate mixture of biomass gasification gas. Polyaromatic hydrocarbons such as benzene, present in tar in biomass derived gas, affect the combustion emissions depending on their concentration in the fuel gas.

  • 322.
    Bakmeedeniya, Lekha Udayanganie
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    MODELLING POLYGENERATION WITH DESICCANT COOLING SYSTEM FOR TROPICAL (AND SUB - TROPICAL) CLIMATES2011Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Modelling Polygeneration with Desiccant Cooling System for Tropical(and Sub Tropical) ClimatesAbstractSpace cooling has become a necessity in tropical countries. Maintainingcomfortable indoor conditions in industrial environments incur high energy bills due toheavy dependency on electrically operated air conditioning systems. In order to exploreways and means to improve the energy efficiency and alternative energy resources, afeasibility study was conducted using a transient simulation software TRNSYS toimplement a combined cooling, heating and power system suitable for a tropicalcountry.It is proven from the literature search that desiccant dehumidification inconjunction with evaporative coolers can reduce air conditioning operating costssignificantly since the energy required to power a desiccant cooling system is small andthe source of this required energy can be diverse.(Low exergy heat such as solar, wasteheat and natural gas)This research is conducted to evaluate the performance and applicability ofdesiccant cooling systems under tropical climatic conditions. Two operating modes;ventilation and recirculation modes of solid desiccants based open cycle air conditioningthat use waste heat from a CHP plant are analysed to understand their operatingranges, performances and applicability. The model developed is used to propose asuitable desiccant cooling system for a selected industry environment in Sri Lanka.Preliminary results obtained by a parametric analysis for weather data for Colombo, SriLanka shows 0.95 and 1.02 optimum coefficients of performance for the ventilation andrecirculation modes respectively when heat is available at 85°C. Based on thecomparisons of the analysis it is seen that the desiccant cooling appears to be a logicalsupplement for space cooling applications in tropical climates like Sri Lanka. And for thecase study taken to investigate can be proposed with a desiccant cooling system with ahot water storage as the energy supply and it can maintain a COP of about 0.48 undertropical weather conditions.

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    Bakmeedeniya Lekha EGI-2011-105MSC EKV857
  • 323. Balderrama, S.
    et al.
    Lombardi, F.
    Stevanato, N.
    Pena Balderrama, J. Gabriela
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Colombo, E.
    Quoilin, S.
    Automated evaluation of levelized cost of energy of isolated micro-grids for energy planning purposes in developing countries2019In: ECOS 2019 - Proceedings of the 32nd International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Institute of Thermal Technology , 2019, p. 2999-3012Conference paper (Refereed)
    Abstract [en]

    Countries around the world are preparing to give the last leap to accomplish a 100 % of rural energy access. Nonetheless, country-wide electrification planning requires the analysis of hundreds of un-electrified villages with different social, economical and geographical backgrounds. State-of-the-art planning models typically handle this computationally challenging task relying on highly-simplified technological characterizations, at the expense of a proper estimation of the cost-optimal potential of off-grid technologies, particularly micro-grids. In this paper, we propose a machine-learning method to improve such technological characterization while keeping the computational tractability of the problem under control. Firstly, field surveys from rural un-electrified villages in Bolivia are used as an input for a stochastic load generator model, creating several demand scenarios for a set of different village archetypes; secondly, renewable energy time series for representative locations of Bolivia are created using the NASA database. For each demand and renewables potential combination, a two-stage stochastic sizing model is adopted to obtain the corresponding cost-optimal micro-grid configuration. Finally, these data are used to train a Gaussian process regression with the levelized cost of energy (LCOE) as dependent variable and the daily average demand, renewable energy, and techno-economic characteristics of the components as independent variables. The results show that the trained algorithm is ultimately able to identify the LCOE of microgrids in given conditions, out of the training dataset, with satisfying accuracy and limited computational effort.

  • 324. Balderrama, S.
    et al.
    Peña, Gabriela
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis. San Simon University, Cochabamba, Bolivia.
    Lombardi, F.
    Stevanato, N.
    Sahlberg, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Howells, Mark I.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Colombo, E.
    Quoilin, Sylvain
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Model-base cost evaluation of microgrids systems for rural electrification and energy planning purposes2020In: Proceedings of the ISES Solar World Congress 2019 and IEA SHC International Conference on Solar Heating and Cooling for Buildings and Industry 2019, International Solar Energy Society , 2020, p. 1638-1647Conference paper (Refereed)
    Abstract [en]

    With pressing priorities in the development agenda, policy makers in developing countries are in the difficult situation of prioritizing policy actions. Limited government and utility budgets need cost effective solutions to bring the desired development benefits of electrification, health, education and food security among others. Energy access is a prerequisite for economic activity and for human development as interacts in synergy with other development needs. As rural electrification models usually focus on the supply of electricity solely, thermal energy needs, such as cooking and water heating remain unattended and satisfied by non-renewable energy fuels. To this aim, we explore optimal electrification solutions addressing two types of energy demands, electricity and thermal energy demands for cooking. Our model builds on a 3-step electrification methodology proposed by Peña et al. including electricity as a modern source of clean energy for cooking in rural communities. The total investments needed to build and operate the microgrids, including distribution costs, is 332 million USD. This is equivalent to 1129 USD/per inhabitant. This amount does not account however the health and environment benefits that e-cooking can bring to inhabitants in Bolivian low-lands.

  • 325.
    Balderrama, Sergio
    et al.
    Univ Liege, Integrated & Sustainable Energy Syst, Liege, Belgium.;San Simon Univ, Ctr Univ Invest Energia, Cochabamba, Bolivia..
    Lombardi, Francesco
    Politecn Milan, Dept Energy, Milan, Italy.;Delft Univ Technol, Dept Engn Syst & Serv, Delft, Netherlands..
    Stevanato, Nicolo
    Politecn Milan, Dept Energy, Milan, Italy.;FEEM Fdn Eni Enrico Mattei, Milan, Italy..
    Pena Balderrama, J. Gabriela
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Colombo, Emanuela
    Politecn Milan, Dept Energy, Milan, Italy..
    Quoilin, Sylvain
    Univ Liege, Integrated & Sustainable Energy Syst, Liege, Belgium..
    Surrogate models for rural energy planning: Application to Bolivian lowlands isolated communities2021In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 232, article id 121108Article in journal (Refereed)
    Abstract [en]

    Thanks to their modularity and their capacity to adapt to different contexts, hybrid microgrids are a promising solution to decrease greenhouse gas emissions worldwide. To properly assess their impact in different settings at country or cross-country level, microgrids must be designed for each particular situation, which leads to computationally intractable problems. To tackle this issue, a methodology is proposed to create surrogate models using machine learning techniques and a database of microgrids. The selected regression model is based on Gaussian Processes and allows to drastically decrease the computation time relative to the optimal deployment of the technology. The results indicate that the proposed methodology can accurately predict key optimization variables for the design of the microgrid system. The regression models are especially well suited to estimate the net present cost and the levelized cost of electricity (R-2 = 0.99 and 0.98). Their accuracy is lower when predicting internal system variables such as installed capacities of PV and batteries (R-2 = 0.92 and 0.86). A least-cost path towards 100% electrification coverage for the Bolivian lowlands mid-size communities is finally computed, demonstrating the usability and computational efficiency of the proposed framework.

  • 326.
    Ballard, Claire
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Conceptual lay-out of small launcher2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The objective of this diploma thesis is to perform a conceptual lay-out of a small launcher. Re- quirements have been defined in order to realize this first preliminary study and design of a small launcher. In that frame, a MATLAB code has been written in order to simulate the rocket tra- jectories. An optimization program on launcher staging has been written as well. To validate this code, the VEGA and Ariane 5 launchers have been used. Then from studies on existing launchers, simulations have been performed in order to find an optimum small launcher and later on to design more precisely the small launcher. As a requirement an upper stage has been newly designed for the purpose of the study. At the end, two small launchers have been considered: a three-stage launcher using the Zefiro 23 as a first stage, the Zefiro 9 as a second stage, and an upper stage using a 3kN thrust engine; a two-stage launcher using the Zenit booster engine in the first stage, and an upper stage using a 22kN thrust engine.

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  • 327.
    Banda, Nelson
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    The Viability of Jatropha Biodiesel Production in Zambia2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    A study of the viability of jatropha biodiesel is presented. It is found that at a crude oil price of US$ 72 per barrel, the ex-refinery cost of a litre of diesel is US$ 0.91 per litre while that of biodiesel is US$ 1.42. Thus a subsidy of US$ 0.51 per litre is needed to make jatropha biodiesel cost competitive with its fossil counterpart.  Such a subsidy poses a threat to national food security as farmers may be induced to abandon the production of food crops in favour of that of jatropha biodiesel. If jatropha diesel is produced without the benefit of fossil fuel, it gives a net yield of only 3 l/ha. At that effective yield, Zambia needs 57 percent (17.2 million km2) of Africa’s total land area in order to produce enough biodiesel to satisfy her annual consumption when the oil runs out. A planet with a total land area 1,100 bigger (about 164 billion km2) than that of the Earth would be needed to grow enough jatropha to replace the present global consumption of crude oil.  It seems clear therefore that biodiesel production from jatropha is not feasible.

  • 328.
    Bandara, Jayasinghe
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    An Integrated Power Supply System for Water Pumping and Lighting in a Rural Village Utilizing Renewable Energy Sources2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    Bandara_Jayasinghe_EGI-2015-096MSC EKV1118
  • 329.
    Barragán, Camila
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Reducing emissions in the Mexican power sector: Economic and political feasibility analysis of policy mechanisms2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A comparative assessment of market-based climate policy instruments –carbon tax vs. ETS– for emission reduction in the Mexican electricity sector is presented. Model-based scenarios of different tax and cap levels were simulated on an existing Balmorel partial equilibrium model populated with data from the Mexican electricity system. The simulation results served to compare the performance of both instruments according to economic criteria. The analysis was further developed with the empirical evidence obtained from international experiences with both instruments, allowing to conclude on the first-best normative instrument based on an economic approach. The assessment was complemented with a political feasibility perspective, through the development of an on-line survey and in-depth interviews with representatives of the relevant stakeholder groups within the country. The first-best instrument was not favoured by the stakeholders, but the study allowed to hint a second-best alternative with a better probability of being fully implemented. The results of this project are useful to guide the necessary debate surrounding the selection of the most appropriate carbon-pricing mechanism for emissions reduction in the country, in particular in the electricity sector.

    A wide-coverage carbon tax with no exemptions and with revenue-recycling mechanisms, gradually increasing to 15 USD/tCO2 would be the first-best instrument from the economic perspective. However, when complementing the analysis with the political feasibility perspective, the most appropriate instrument for emissions reduction in the Mexican electricity sector is an emissions trading system with the cap set as the conditional target of the INDCs, with auctioned allowance allocation and an auctioning floor-price, set at a similar but lower value than the equivalent carbon tax. Such an instrument is in line with the priorities of the stakeholder groups and would generate a stable price signal, allowing for the earmarking of carbon revenue, and would avoid exempting natural gas from carbon pricing.

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  • 330.
    Barragán-Beaud, Camila
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS. Department of Mechanical Engineering, Aalto University, School of Engineering, Aalto, Finland.
    Pizarro-Alonso, A.
    Xylia, Maria
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Syri, S.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Carbon tax or emissions trading?: An analysis of economic and political feasibility of policy mechanisms for greenhouse gas emissions reduction in the Mexican power sector2018In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 122, p. 287-299Article in journal (Refereed)
    Abstract [en]

    This study provides a comparative assessment of carbon-pricing instruments for the Mexican electricity sector, contrasting a carbon tax with an emissions trading scheme (ETS). The assessment is performed in terms of economic impacts and political feasibility. Model-based scenarios considering different price and quantity levels are analyzed on Balmorel-MX, a cost optimization bottom-up model of the Mexican electricity system. The political feasibility is evaluated using an online survey and interviews with representatives of relevant stakeholder groups. The assessment suggests that an ETS is the most appropriate instrument for the Mexican case. We recommend to set the cap as 31% abatement in relation to a baseline, which is suggested to be 102 MtCO2 by 2030, given the business-as-usual baseline used as reference by the Mexican government (202 MtCO2) is found to leave cost-effective abatement potential untapped. An emission trading system with such design has higher cost-efficiency and lower distributional effects than a carbon tax at equivalent ambition level (15 USD/tCO2). The political feasibility analysis confirms the assessment, as it is in line with the priorities of the stakeholder groups, allows earmarking carbon revenue and avoids exempting natural gas from carbon pricing.

  • 331.
    BARRY, Raphael
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Sustainable Building Design with Autodesk Ecotect2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
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  • 332.
    Bartknecht, Felix
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Creating a Tool for Performance Assessment of Heat Extraction using the Example of the Combined Heat and Power Plant Heilbronn2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is dealing with the development of a calculation model representing the processes of electricity generation and heat extraction of the combined heat and power (CHP) plant Heilbronn (Germany). Using the thermodynamic simulation software EBSILON® Professional, a tool is created, which is applied to elaborate possible optimization potentials and which enables analyzing existing operation procedures. In collaboration with the Royal Institute of Technology Stockholm and EnBW Energie Baden-Württemberg AG necessary boundary conditions are specified in order to construct a model, which on one hand simplifies the complex process design into an easy understandable and user-friendly program and which on the other is still able to describe the real mechanisms as accurately as necessary. Thereby this work defines design configurations, data input and calculation procedures in order to determine the qualifying factors required.

    On the basis of a general description of the power plant and background information about the simulation software used, first of all the essential data points and approach of the development process and selection of components are stated. Thereby the implementation of base data and possible assumptions are defined, while the model is built in a number of steps. Afterwards the different parts are put together and the created tool is checked for its plausibility by comparing simulated values with real measurement data (trial runs). The different components’ characteristics are adjusted and existing and alternative processes of the district heating and process steam systems are simulated. 

    In this study not only the model creation itself, but also its application is investigated. Hereby two exemplary plant conditions are reconstructed and changes made in order to see how the system’s thermodynamic properties (temperature, pressure and enthalpy), mass flows and efficiencies adapt to new situations.  Thereby nonexistent data points can be determined and analyzed.  Beyond that important factors in the supply structure (bottlenecks) are pointed out as well as energy outputs, flow rates, temperatures and CO2-emmissions are investigated and evaluated.

    In the future the created tool will be used to make an economic analysis, not only of the district heating system itself, but be part of a larger research – in combination with other studies – investigating the performance of the whole power plant. The developed concept aims for the implementation at the CHP plant in Heilbronn and will support the decision making process while saving time and money resources.

  • 333.
    Bartl, Jan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Wake Measurements Behind An Array Of Two Model Wind Turbines2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the last decades the exploitation of energy from the wind has become one of the most promising renewable energy technologies. The main strive in today’s development of wind turbines is to increase the efficiency of the turbine and to build bigger rotors that are able to extract more power out of the wind. When it comes to the planning and designing of a wind park, also the aerodynamic interactions between the single turbines must be taken into account. The flow in the wake of the first row turbines is characterized by a significant deficit in wind velocity and by increased levels of turbulence. Consequently, the downstream turbines in a wind farm cannot extract as much power from the wind anymore. Furthermore, the additional turbulence in the wake could be a reason for increased material fatigue through flow-induced vibrations at the downstream rotor. The main focus of this experimental study is to investigate the local velocity deficit and the turbulence intensities in the wake behind an array of two model wind turbines. For two different turbine separation distances, the wake is scanned at three different downstream positions. The experiments are performed at the wind tunnel (1.9m x 2.7m cross section) at NTNU Trondheim using two model wind turbines with a rotor diameter of 0.9m. A hot wire probe is used to scan the wake behind the model turbines in defined positions.

    Moving axially downstream the velocity deficit in the wake gradually recovers and the turbulence intensity levels slowly decrease. Furthermore, a gentle expansion of the wake can be observed. The wake profiles measured in close distances behind the rotor are characterized by evident asymmetries. Further downstream in the wake turbulent diffusion mechanisms cause a more uniform and more symmetrical flow field. Moreover, the turbulence intensity behind the second wind turbine is found to be significantly higher than behind one unobstructed turbine. Also, considerably higher velocity deficits are found in the near wake behind the second turbine compared to the wake behind one unobstructed turbine. However, the velocity profile at five rotor diameters downstream in the wake behind the second turbine is already very similar to the velocity distribution behind the first turbine. Furthermore, the velocity field and turbulence intensity distribution in the wake behind the second turbine is more symmetrical and more uniform than behind the first turbine.

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  • 334.
    Basar, Ezgi
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Capacity Building for Energy Performance Contracting in European Union2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Energy Performance Contracting (EPC) is an important tool to disseminate energy efficiency measures. This study focuses on the main barriers and success factors for EPC market in order to build capacity in this subject. A pilot study of questionnaire took part among the local authorities of four countries within the European Union; Croatia, Denmark, Czech Republic and Slovakia. The results of this pilot study were combined with the results of a literature research to identify common disadvantages and key points of the market. Afterwards, the most important actions to be taken on national and international level in European Union were discussed. According to this study, the supportive legal framework for the energy efficiency measures, access to financial resources, reliable energy consumption data and trust in Energy Service Companies (ESCOs) were remarked as the essential factors for increasing the capacity of the EPC.

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    Basar Ezgi EGI-2013-108MSC
  • 335. Basile, A.
    et al.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Iulianelli, A.
    Cigolotti, V.
    European Fuel Cell 20112013In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 38, no 1, p. 319-319Article in journal (Other academic)
  • 336.
    Bastien, Étienne Joseph Marcel
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Towards Circular Economy: Wood ash management for biomass CHP plants in the UK2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In response to climate change, the United Kingdom has committed to reach net zero greenhouse gas emissions by 2050. To reach the set target, the Committee on Climate Change is planning a notable increase of bioenergy up to 15% in the national energy mix and thus an increase of the amount of ash produced. Nowadays, ash is rarely recycled or reused but mostly landfilled, which is both costly for the industry and unsustainable. In parallel, agricultural land and forestry suffer both from soil acidification and nutrient depravation due to the intensive land utilization practices.

    This study reviews the potential of a circular economy of wood ash for application on land and forestry through a case study based on the ash generated by two biomass-fired CHP plants in the UK. It summarizes the general ash characteristics, the factors influencing its quality, and the optimal composition sought for application to land and forestry. The study also aims at defining the main concerns with regards to potential contamination of the environment and dangers to human health. Eventually, the process to evaluate and establish recycling of the ash for both plants was analysed in light of the above.

    The study found that ash is a remarkably variable co-product, depending mainly on the fuel input and combustion conditions. Ash is a good replacement for agricultural lime and conserves a notable part of the biomass fuel nutrients. It was estimated that ash could cover a significant part of the liming and fertilising demand in the UK by 2050, and deliver a substantial financial value to a power plant. However, contamination concerns are present, especially heavy metals, which could lead to damage on the environment and reduction of the growth rate.

    The study found that ash recycling in the UK is currently a challenging process, that should not be overlooked when designing a biomass project. When they exist, procedures are demanding with regards to testing, which can financially deter power plants to engage in ash recycling processes.

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  • 337.
    Bataille, Christopher
    et al.
    Inst Dev Durable & Relat Int IDDRI Org, 41 Rue Four, F-75006 Paris, France..
    Waisman, Henri
    Inst Dev Durable & Relat Int IDDRI Org, 41 Rue Four, F-75006 Paris, France..
    Briand, Yann
    Inst Dev Durable & Relat Int IDDRI Org, 41 Rue Four, F-75006 Paris, France..
    Svensson, Johannes
    Inst Dev Durable & Relat Int IDDRI Org, 41 Rue Four, F-75006 Paris, France..
    Vogt-Schilb, Adrien
    Inter Amer Dev Bank IADB Org, 1300 New York Ave NW, Washington, DC 20577 USA..
    Jaramillo, Marcela
    Inter Amer Dev Bank IADB Org, 1300 New York Ave NW, Washington, DC 20577 USA..
    Delgado, Ricardo
    Univ Andes, Sch Engn, Bogota, Colombia..
    Arguello, Ricardo
    Univ Rosario, Fac Econ, Bogota, Colombia.;Univ Ibague, Fac Econ & Adm Sci, Ibague, Colombia..
    Clarke, Leon
    Univ Maryland, Ctr Global Sustainabil, Sch Publ Policy, College Pk, MD 20740 USA..
    Wild, Thomas
    Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20740 USA..
    Lallana, Francisco
    Fdn Bariloche, Energy Dept, RA-8400 San Carlos De Bariloche, Argentina..
    Bravo, Gonzalo
    Fdn Bariloche, Energy Dept, RA-8400 San Carlos De Bariloche, Argentina..
    Nadal, Gustavo
    Fdn Bariloche, Energy Dept, RA-8400 San Carlos De Bariloche, Argentina..
    Le Treut, Gaelle
    Ctr Int Rech Environm & Dev CIRED, Nogent Sur Marne, France..
    Godinez, Guido
    Univ Costa Rica, Sch Elect Engn, San Jose, Costa Rica..
    Quiros-Tortos, Jairo
    Univ Costa Rica, Sch Elect Engn, San Jose, Costa Rica..
    Ramos, Eunice
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Howells, Mark
    Loughborough Univ, Epinal Way, Loughborough LE11 3TU, Leics, England.;Imperial Coll London South Kensington, London SW7 2BU, England..
    Buira, Daniel
    Tempus Analitica AC, Mexico City, DF, Mexico..
    Tovilla, Jordi
    Tempus Analitica AC, Mexico City, DF, Mexico..
    Farbes, Jamil
    Evolved Energy Res, San Francisco, CA 94115 USA..
    Ryan, Jones
    Evolved Energy Res, San Francisco, CA 94115 USA..
    De La Torre Ugarte, Daniel
    Univ Pacifico, Lima, Peru.;Univ Tennessee, Knoxville, TN USA..
    Collado, Mauricio
    Univ Pacifico, Lima, Peru..
    Requejo, Fernando
    Univ Pacifico, Lima, Peru..
    Gomez, Ximena
    Univ Pacifico, Lima, Peru..
    Soria, Rafael
    Escuela Politec Nacl, Dept Ingn Mecan, Ladron de Guevara E11-253, Quito 17012759, Ecuador..
    Villamar, Daniel
    Escuela Politec Nacl, Dept Ingn Mecan, Ladron de Guevara E11-253, Quito 17012759, Ecuador..
    Rochedo, Pedro
    Univ Fed Rio de Janeiro, Grad Sch Engn, Energy Planning Program, Ctr Tecnol, Bloco C,Sala 211,Cidade Univ, BR-21941972 Rio De Janeiro, RJ, Brazil..
    Imperio, Mariana
    Univ Fed Rio de Janeiro, Grad Sch Engn, Energy Planning Program, Ctr Tecnol, Bloco C,Sala 211,Cidade Univ, BR-21941972 Rio De Janeiro, RJ, Brazil..
    Net-zero deep decarbonization pathways in Latin America: Challenges and opportunities2020In: Energy Strategy Reviews, ISSN 2211-467X, E-ISSN 2211-4688, Vol. 30, article id 100510Article in journal (Refereed)
    Abstract [en]

    This synthesis paper presents the objectives, approach and cross-cutting results of the Latin American Deep Decarbonization Pathways project (DDP-LAC). It synthesizes and compares detailed national and sectoral deep decarbonization pathways (DDPs) to 2050 compatible with the Paris Agreement objectives and domestic development priorities in Argentina, Colombia, Costa Rica, Ecuador, Mexico and Peru. The first five countries analysed in detail the energy system and agriculture, forestry and land use (AFOLU) at a high level, while Peru focussed on a detailed analysis of AFOLU given its predominance in its GHG emissions. While economy-wide results were produced, this paper focuses on the electricity, passenger transport, and AFOLU results because of their current emissions, potential to grow, and identification of successful strategies for decarbonization (e.g. switching to clean electricity and other net-zero emissions fuels across the economy; urban planning, mode shifting, and electrification in passenger transport; and intensive sustainable agriculture, assignment of land use rights and their enforcement and afforestation in AFOLU). It also highlights where significant emissions remain in 2050, notably in industry, AFOLU, freight, and oil and gas production, all areas for future research. It derives insights for the design of domestic policy packages and identifies priorities for international cooperation. This analysis provides critical information for Long-Term Strategies, Nationally Determined Contributions and Global Stocktaking in the context of the Paris Agreement.

  • 338.
    Bateebe, Irene
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Investigation of Probable Pollution from Automobile Exhaust Gases in Kampala City, Uganda: To Assess the current automobile exhaust gas emission levels and characterize the emissions from different automobile types2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is estimated that transport sources in developing countries contribute about 4% of the global fossil carbon dioxide versus 18% by industrialized countries. The cost of urban air pollution is estimated to be 2% of GDP in developed countries and more than 5% in developing countries. With an annual vehicle registration growth of over 30% in 2008 and a population growth rate of 6%, the number of automobiles in Kampala city of Uganda is expected to continue growing exponentially. Most of the vehicles used are imported into the country when quite old with worn out engines and low energy efficiencies. As a result, such vehicles profusely emit exhaust gases which may be harmful to both human health and the environment. Controlling pollution from the transport sector is vital to improving the quality of air and protecting public health. The objective of this dissertation was to determine the level of pollution from automobile exhaust gases in Kampala City and its impacts on human health and the environment. The study involved the analysis of tail pipe emissions using a gas analyser. It covered mini buses, motorcycles and personal vehicles which constitute 92% of the Kampala vehicle parc. It was established that the main types of exhaust gases from the automobiles were CO2,  NOx, CO, NO and HC. The findings estimated the highest level of NOx tail pipe emissions at 0.15 mg/m3, HC emissions at 2.59 mg/m3, CO at 110 mg/m3 and 286.6 mg/m3 for CO2. The reported ambient air emissions were estimated at 0.18 ppm, 14000 ppm and 1.3 ppm corresponding to NO2, CO2 and CO, respectively. The study further investigated the impact of four mitigation methods on emission levels using the LEAP model. The impact of increasing penetration of city buses, introduction of tail pipe emission standards and hybrid cars and improvement of vehicle fuel economy were investigated. It was found that if left unabated, the emissions will continue to grow with the increasing number of motor vehicles. Implementation of the proposed mitigation methods resulted in a reduction in the GWP reduced by 52%, 51%, 17% and 8.5%, respectively. It is recommended that a comprehensive motor vehicle pollution control program be designed to implement the proposed NEMA vehicle emission standards. Establishment of an integrated transport system promoting the growth in number of city buses should be made a priority to reduce on emission levels and enable the decongestion of Kampala city.

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    Bateebe Irene EGI - 2011-091EKV853
  • 339.
    Batili, Hazal
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Hamawandi, Bejan
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Ergül, Adem Björn
    KTH, School of Engineering Sciences (SCI), Applied Physics, Nanostructure Physics.
    Toprak, Muhammet
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering. KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration. KTH, School of Biotechnology (BIO), Centres, Albanova VinnExcellence Center for Protein Technology, ProNova. KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics. KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    On the electrophoretic deposition of Bi2Te3 nanoparticles through electrolyte optimization and substrate design2022In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, E-ISSN 1873-4359, Vol. 649, p. 129537-, article id 129537Article in journal (Refereed)
    Abstract [en]

    Assembly of thermoelectric nanostructures with pre-defined morphology and surface chemistry on solid sub-strates has been one of the challenges for in-plane TE devices. Electrophoretic deposition (EPD) has the potential to be used for this purpose, where the use of non-conductive substrates is required to enable a reliable evaluation of the transport property of electrically active films. Bi2Te3 nanoparticles, which were synthesized using microwave-assisted hydrothermal route, were used for the EPD of thermoelectric films on glass substrates. A special substrate was fabricated using maskless photolithography, to evaluate the electronic transport properties of the TE films without the interference of the substrate. Electrolyte composition was optimized for high mobility of the suspended nanoparticles, and Bi2Te3 EPD films were fabricated with a high deposition rate, reaching 10 mu m/min. Initial EPD films showed high resistivity, ascribed to the surface oxide layer and capping ligands. The resistance was significantly reduced by the addition of a dithiol molecular linker, capable of interconnecting the Bi2Te3 nanoparticles through ligand-exchange. Seebeck coefficient in the range-150 to-180 mu V/K was measured, revealing the transport through the deposited films. Finally, a power factor of 169 nW/K-2.m was estimated, revealing the potential for the application of this technology to large area TE films as active coatings using the developed EPD process.

  • 340.
    BAUDREY, Xavier
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    How to develop onshore wind farm projects in France under the new Grenelle 2 law2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the rising global warming issue and an ever-increasing dependency oil problem, wind power seems to be an alternative source of energy which is clean, non-polluting, and cost effective. The European 20-20-20 goals as well as national targets for the next ten years require a substantial increase in installed renewable capacity in France. Maïa Eolis is a leading French wind project developer and independent renewable energy producer which helps France to meet its new renewable energy targets. Even if the general opinion on wind energy is rather positive, developing a wind power project is a complex process in France because there are many regulations and new environmental constraints due to the Grenelle 2 law. Many administrative and legislative barriers consequently slow down every step of the development process. This includes handling and coordinating the permitting and application process, realizing pre-feasibility studies, and identifying the best suited sites for wind turbines, taking into account obstacles, aesthetics, and other environmental issues, in order to capture as much wind as possible. Ensuring local support is another key element of the success of a project in order to integrate it in the best possible way in its environment.

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    fulltext
  • 341. Bauer, N.
    et al.
    Hilaire, J.
    Brecha, R. J.
    Edmonds, J.
    Jiang, K.
    Kriegler, E.
    Rogner, Hans-Holger
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis. Int Inst Appl Syst Anal IIASA, Austria.
    Sferra, F.
    Assessing global fossil fuel availability in a scenario framework2016In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 111, p. 580-592Article in journal (Refereed)
    Abstract [en]

    This study assesses global, long-term economic availability of coal, oil and gas within the Shared Socio-economic Pathway (SSP) scenario framework considering alternative assumptions as to highly uncertain future developments of technology, policy and the economy. Diverse sets of trajectories are formulated varying the challenges to mitigation and adaptation of climate change. The potential CO2 emissions from fossil fuels make it a crucial element subject to deep uncertainties. The analysis is based on a well-established dataset of cost-quantity combinations that assumes favorable techno-economic developments, but ignores additional constraints on the extraction sector. This study significantly extends the analysis by specifying alternative assumptions for the fossil fuel sector consistent with the SSP scenario families and applying these filters (mark-ups and scaling factors) to the original dataset, thus resulting in alternative cumulative fossil fuel availability curves. In a Middle-of-the-Road scenario, low cost fossil fuels embody carbon consistent with a RCP6.0 emission profile, if all the CO2 were emitted freely during the 21st century. In scenarios with high challenges to mitigation, the assumed embodied carbon in low-cost fossil fuels can trigger a RCP8.5 scenario; low mitigation challenges scenarios are still consistent with a RCP4.5 scenario.

  • 342. Bazilian, M.
    et al.
    Miller, M.
    Detchon, R.
    Liebreich, M.
    Blyth, W.
    Futch, M.
    Modi, V.
    Jones, L.
    Barkett, B.
    Howells, M.
    MacGill, I.
    Kammen, D. M.
    Mai, T.
    Wittenstein, M.
    Aggarwal, S.
    O'Malley, M.
    Carvallo, J. P.
    Welsch, Manuel
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Pugh, G.
    Weston, R.
    Arent, D. J.
    Accelerating the global transformation to 21st century power systems2013In: Electricity Journal, ISSN 1040-6190, E-ISSN 1873-6874, Vol. 26, no 6, p. 39-51Article in journal (Refereed)
    Abstract [en]

    Nations and regions need to share lessons about the best ways to create enabling policies, regulations, and markets that get the most social benefit out of power systems and incent the necessary investments.

  • 343.
    Bazilian, Morgan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Chattopadhyay, D.
    Considering power system planning in fragile and conflict states2016In: Energy for Sustainable Development, ISSN 0973-0826, E-ISSN 2352-4669, Vol. 32, p. 110-120Article in journal (Refereed)
    Abstract [en]

    Traditional methods of energy planning are likely to provide results that may be inappropriate in fragile and conflict-prone countries. The risks of violence and damage, or significant delays and cancellations in infrastructure development, are rife in these states. Thus, least-cost planning processes must explicitly address the inherent risks. While there are numerous statistical methods for dealing with decision making under uncertainty, few of them have been applied to power system planning and tailored for these situations. We present a general theoretical framing of the issue and illustrate application of a very simple method to a case study of the Republic of South Sudan. We find that, in general, the resilience aspects, combined with modular and incremental benefits of distributed generation technologies and systems, emerge as attractive options if the various risks of infrastructure development are included in modelling techniques.

  • 344. Bazilian, Morgan
    et al.
    Hobbs, Benjamin F.
    Blyth, Will
    MacGill, Iain
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Interactions between energy security and climate change: A focus on developing countries2011In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 39, no 6, p. 3750-3756Article in journal (Refereed)
    Abstract [en]

    We briefly consider the tensions between climate change and energy security policy imperatives, and highlight some concepts that may bring additional clarity to decision-making at the nexus of the two areas. We focus on developing countries and use the case of the Medupi supercritical coal plant in South Africa. The justification for the plant's construction stemmed from an Integrated Resource Planning process informed by South Africa's national utility. Often, as in the case of South Africa, there are tensions not easily captured in quantitative algorithms between, inter alia, a lack of access to electricity by millions of people (and associated welfare losses) and greenhouse gas emissions from electricity generation. It is difficult to identify any formal processes that have prioritised climate change considerations over those of energy access. Thus, it becomes imperative to have a clear understanding of the consequences of this reality when considering power system expansion. We find that the processes often employed do not provide an entirely satisfactory precedent for future planning analyses, and the justifications do not adequately reflect the complexity of the decision space. Finally, we highlight some options by which these tools might be enhanced in areas including explicit and formal consideration of risk.

  • 345. Bazilian, Morgan
    et al.
    Nussbaumer, Patrick
    Rogner, Hans-Holger
    Brew-Hammond, Abeeku
    Foster, Vivien
    Pachauri, Shonali
    Williams, Eric
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Niyongabo, Philippe
    Musaba, Lawrence
    Gallachoir, Brian O.
    Radka, Mark
    Kammen, Daniel M.
    Energy access scenarios to 2030 for the power sector in sub-Saharan Africa2012In: Utilities Policy, ISSN 0957-1787, E-ISSN 1878-4356, Vol. 20, no 1, p. 1-16Article in journal (Refereed)
    Abstract [en]

    In order to reach a goal of universal access to modern energy services in Africa by 2030, consideration of various electricity sector pathways is required to help inform policy-makers and investors, and help guide power system design. To that end, and building on existing tools and analysis, we present several 'high-level', transparent, and economy-wide scenarios for the sub-Saharan African power sector to 2030. We construct these simple scenarios against the backdrop of historical trends and various interpretations of universal access. They are designed to provide the international community with an indication of the overall scale of the effort required - one aspect of the many inputs required. We find that most existing projections, using typical long-term forecasting methods for power planning, show roughly a threefold increase in installed generation capacity occurring by 2030, but more than a tenfold increase would likely be required to provide for full access - even at relatively modest levels of electricity consumption. This equates to approximately a 13% average annual growth rate, compared to a historical one (in the last two decades) of 1.7%.

  • 346. Bazilian, Morgan
    et al.
    Rice, Andrew
    Rotich, Juliana
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    DeCarolis, Joseph
    Macmillan, Stuart
    Brooks, Cameron
    Bauer, Florian
    Liebreich, Michael
    Open source software and crowdsourcing for energy analysis2012In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 49, p. 149-153Article in journal (Refereed)
    Abstract [en]

    Informed energy decision making requires effective software, high-quality input data, and a suitably trained user community. Developing these resources can be expensive and time consuming. Even when data and tools are intended for public re-use they often come with technical, legal, economic and social barriers that make them difficult to adopt, adapt and combine for use in new contexts. We focus on the promise of open, publically accessible software and data as well as crowdsourcing techniques to develop robust energy analysis tools that can deliver crucial, policy-relevant insight, particularly in developing countries, where planning resources are highly constrained-and the need to adapt these resources and methods to the local context is high. We survey existing research, which argues that these techniques can produce high-quality results, and also explore the potential role that linked, open data can play in both supporting the modelling process and in enhancing public engagement with energy issues.

  • 347. Bazilian, Morgan
    et al.
    Rogner, Holger
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Hermann, Sebastian
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Arent, Douglas
    Gielen, Dolf
    Steduto, Pasquale
    Mueller, Alexander
    Komor, Paul
    Tol, Richard S.J.
    Yumkella, Kandeh K.
    Considering the energy, water and food nexus: Towards an integrated modelling approach2011In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 39, no 12, p. 7896-7906Article in journal (Refereed)
    Abstract [en]

    The areas of energy, water and food policy have numerous interwoven concerns ranging from ensuring access to services, to environmental impacts to price volatility. These issues manifest in very different ways in each of the three "spheres", but often the impacts are closely related. Identifying these interrelationships a priori is of great importance to help target synergies and avoid potential tensions. Systems thinking is required to address such a wide swath of possible topics. This paper briefly describes some of the linkages at a high-level of aggregation - primarily from a developing country perspective - and via case studies, to arrive at some promising directions for addressing the nexus. To that end, we also present the attributes of a modelling framework that specifically addresses the nexus, and can thus serve to inform more effective national policies and regulations. While environmental issues are normally the 'cohesive principle' from which the three areas are considered jointly, the enormous inequalities arising from a lack of access suggest that economic and security-related issues may be stronger motivators of change. Finally, consideration of the complex interactions will require new institutional capacity both in industrialised and developing countries.

  • 348.
    Bazilian, Morgan
    et al.
    United Nations Industrial Development Organisation, Vienna, Austria.
    Welsch, Manuel
    United Nations Industrial Development Organization, Vienna, Austria.
    Divan, Deepak
    Georgia Institute of Technology, Atlanta, USA.
    Elzinga, David
    International Energy Agency, Paris, France.
    Strbac, Goran
    Imperial College London, London, UK.
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Jones, Lawrence
    ALSTOM Grid, Washington DC, USA.
    Keane, Andrew
    University College Dublin, Dublin, Ireland.
    Gielen, Dolf
    International Renewable Energy Agency, Abu Dhabi, UAE.
    Balijepalli, V. S. K. Murthy
    Indian Institute of Technology, Bombay, India.
    Brew-Hammond, Abeeku
    Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
    Yumkella, Kandeh
    United Nations Industrial Development Organisation.
    Smart and Just Grids: Opportunities for sub-Saharan Africa2011Report (Other academic)
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    Smart and Just Grids - Opportunities for sub-Saharan Africa
  • 349.
    Beaini, Chadi
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Backup Battery cooling for Radio Base Stations2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Telecommunication systems are expanding around the world. From infrastructure networks to macro and pico systems, including RBS (Radio Base Station). To ensure the availability of RBS during a shortage on the electricity grid,EricssonABdeveloped BBS (Battery Base Stations) and BBU (Battery Base Units). The battery temperature is very critical to the battery life and the battery’s electrical performance. Taking energy efficiency and environmental issues in consideration, the need of a battery thermal management system increases. Therefore, sustainability is included to the core of this project.

    The performance of VRLA (Valve Regulated Lead-Acid) backup batteries for telecommunication RBS can be greatly improved by keeping an adequate control of the battery temperature. A solid relation between temperature and battery lifetime exists, which urges the need to keep batteries around their optimal life and performance temperature; 25°C. Different ways of cooling currently used atEricssonABare presented in this paper, including different ways of improving the cooling system performance. By testing, the variation of battery temperature with different air gaps separating the batteries were monitored.

    Other cooling methods, such as liquid cooling and PCM (Phase Change Materials) were also studied. Literature studies and test results showed a promising potential for such technologies to be granted green light to be used for future products. Tests were made to study the thermal conduction within battery cells. The efficiency of liquid cooling was tested as well; a cold plate heat exchanger was manufactured and used for the preliminary testing.

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    Master's Thesis - Chadi Beaini
  • 350.
    BEAUVISAGE, Audry
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Market opportunities to develop wind power in North Africa2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    fulltext
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