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  • 2351.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Hydro-meteorological processes driving solute transport in Lake VictoriaManuscript (preprint) (Other academic)
    Abstract [en]

    This study explores by a vertically integrated tracer transport model, hydro-meteorological event characteristics and their influence on solute transport. Changes in Hydro-meteorological processes and increasing frequency of extreme weather events are responsible for changing the lake water balance, influencing streamflow variations, and lake tracer transport. We compare historical data over a long time with model data from a vertically integrated model in Comsol Multiphysics. We consider water balance, sources of data uncertainty, correlations, extreme rain and inflow years, and seasonal variations. The lake transport model has estimated soluble loading and transportation. The results showed that the lake rainfall is seasonal; there are strong correlations between tributary inflows and precipitation, and between lake outflow and water level. It was found that “events” influence lake level fluctuations. The solute transport was shown to vary more in wet periods. Modeled transportations were higher in Kenya and Uganda lake zones than in Tanzanian zones. The major inflow, from the Kagera river, appears to strongly influence lake solute transportation, so the composition of this river must be considered.

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  • 2352.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Murchison Bay surface water pollution transport mechanismsManuscript (preprint) (Other academic)
    Abstract [en]

    The water quality of the inner Murchison Bay (MB) is polluted by complex mixture processes, these are: pollution and nutrients loading, river inflows, lake water levels, wetland management and flora and fauna populations. Present study is analysing inner Murchison Bay (MB) water pollution by using wind and hydrodynamic numerical model technique. 

  • 2353.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Hydrodynamic wind induce model influencing inner Murchison Bay flow circulation2019Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Wind stress is exerted by the wind on the lake surface may be important for lake flow analysis and the Inner Murchison Bay is strongly influenced by urban pollution from Uganda Capital Kampala and bay is highly eutrophic cause of back and forth nutrient movement. The rapid population growth, growing commercial activities and industrialization in Kampala, Uganda coupled with inadequate provision of waste management services which have led to increase volume of urban waste entering the North-Western part of Lake Victoria. The Murchison Bay (MB) is in the Northern part of Lake Victoria in Uganda which has for decades received a daily wastewater load of 0.2 % of its volume from Kampala City of Uganda, through the Nakivubo channel [1]. Kampala City people habitants 1.7 million. The uncontrolled solid waste seen along roadsides and storm water drains enter the Nakivubo Channel. The Nakivubo channel is ended in a papyrus swamp in Uganda that retained a large portion of water pollution before it reached in the inner Murchison Bay [2]. In addition, the channel is widened in 2001-2003 to improve the city drainage which has increased the potential loading of nutrients to the bay. The partially treated effluent from treatment plants are mixed with the water in channel and it contribute a high significant pollution load, and is the most polluted system by organic matter in solid waste and wastewater discharged from slums and un-sewered areas, Luzira Prison and small & large scale industries [3]. There are urgent need to resolve the problem. Nowadays, the inner Murchison Bay (MB) water quality are destroying by several complex mixture processes, Ex.: pollution and nutrients loading, river inflows, un-sewered water, wetland management and flora and fauna populations. Present study is focusing on inner Murchison Bay (MB) water pollution behaviour by using wind speed hydrodynamic model. The model processes are determining the fate and transport of pollutant that are vertically mixing (wind force) and horizontal flow (advection-dispersion) analysis. Vertically transport of wind flow that is forcing on the lake water surface are analysed by the vertically integrated Shallow Water Equation model. Horizontally transport of pollution of water and its flow and speed are analyzing by advectiondispersion and diffusion model. Result shows that the horizontal mixing is continuing with lake nutrients and the vertically wind flow from MB into lake is also determine the mixing of lake water which is not much affecting the lake nutrients. 

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  • 2354.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Lyon, Steve W.
    School of Environment and Natural Resources, The Ohio State University, Columbus, OH 43210, USA.
    Potential wind influences adopted for evaluating surface-water transport processes of Lake VictoriaManuscript (preprint) (Other academic)
    Abstract [en]

    The lake surface water directly influenced by wind force, named the surface boundary layer, is where most pollution release and mixing occurs. The dynamical process of wind force matches the speed of the surface currents and a wind shear is generated over the lake depth. This paper used measurements and numerical modeling of Lake Victoria and the Murchison Bay (MB) to assess the transport of pollutants focusing on nearshore phenomena characterized through wind stress hydrodynamics. Singular value decompositions of wind speed and wind directions were used for pattern analysis considering data from three Tanzania and one Uganda locations at multiple temporal scales. Results showed that strong winds blow typically at midday for daily wind patterns and at mid-year for seasonal wind patterns. Further analysis of the daily, monthly, and yearly wind speeds showed there was a significant periodical trend over these temporal scales. Based on these wind data, a vertically integrated shallow water equations model was applied to explore the potential role of wind for water and pollution movement for the MB surface water. Results showed that the MB wind stress would need to move the whole water column and that would occur much too slowly for the wind to be a dominant factor in the transport of pollutants. Further, we discovered that the depth-resolved hydrostatic model considered required artificial dissipation for stability. Based on the wind patterns and our modeling results, it appears that full Navier-Stokes equations resolved with depth would be required to accurately model the role of wind on lake hydrodynamics. As such, further analysis would be needed to ascertain the true role of wind on mixing and transport in MB and Lake Victoria. 

  • 2355.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Reinardy, Benedict T. I.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Walakira, David Ddumba
    Makerere University, Kampala, Uganda.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Ernstson, Henrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    A shallow water numerical method for assessing impacts of hydrodynamics and nutrient transport processes on water quality values of Lake VictoriaManuscript (preprint) (Other academic)
    Abstract [en]

    Lake Victoria is the world’s largest tropical lake and the third-largest water body, providing significant water resources for surrounding environments including the cultural, societal, and livelihood needs of people in its basin and along the White Nile. The aim of this study was to use decade-long time series of measured lake flow in the lake system and phosphorus deposition to develop a suitable numerical model based on shallow water equations (SWE) for assessing water quality in Lake Victoria, an increasingly important tool under climate variation. Different techniques were combined to identify a numerical model that included: i) a high-resolution SWE model to establish raindrop diffusion to trace pollutants; ii) a two-dimensional (2D) vertically integrated SWE model to establish lake surface flow and vertically transported wind speed flow acting on lake surface water by wind stress; and iii) a site-specific phosphorus deposition sub-model to calculate atmospheric deposition in the lake. A smooth (non-oscillatory) solution was obtained by applying a high-resolution scheme for a raindrop diffusion model. Analysis with the vertically integrated SWE model generated depth averages for flow velocity and associated changes in water level profile in the lake system and showed unidirectional whole lake wind blowing from the southwest to northeast. The atmospheric phosphorous deposition model enabled water value assessment for mass balances with different magnitudes of both inflows and outflows demonstrating annual total phosphorus at 13,500 tons concentrating at mid-lake western and eastern parts. The model developed here is simple and suitable for use in assessing flow changes and lake level changes and can serve as a tool in studies of lake bathymetry and nutrient and pollution transport processes. Our study opens towards refining models of complex shallow-water systems.

  • 2356.
    Paul, Seema
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Walakira, David Ddumba
    Makerere University, Mathematics Department, Kampala, Uganda.
    Oppelstrup, Jesper
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Wait, Richard
    Uppsala University, Scientific Computing Department, Uppsala, Sweden.
    Brokking-Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mango, John
    Makerere University, Mathematics Department, Kampala, Uganda.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Hydrodynamics of Lake Victoria: Vertically integrated flow models in COMSOL Multiphysics.2014In: Proceedings of the 2014 COMSOL Conference in Bangalore, COMSOL, 2014, , p. 3Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Lake Victoria is the largest tropical lake in the world and is very important for environment andeconomy in East Africa. The hydrodynamic processes in the shallow (40-80 m deep) watersystem are unique due to its location at the equator which makes Coriolis effects noticeable alsofor vertical transport. The limited river inflow, and the large surface area compared to its volumemake Lake Victoria vulnerable to climate changes. A model of the circulation patterns, mixing,dispersion and stratification will be necessary to devise strategies for management of the naturalresources. The goal of this project is to improved water quality of Lake Victoria.COMSOL Multiphysics® software supports models for the different processes to be included,and we are developing interfaces used by the geo-hydrodynamical community, such as theDigital Elevation Map (DEM) file format. However, much data remains to collect and coordinatebefore the goal is reached. It turns out that modern depth soundings covering the whole lake maynot be available so scarce and old data have to be used initially. To assess the data collected, amodeling approach can be employed. Data for river in- and outflow as well as evaporation andrainfall have been collected for many years and can be correlated with data series for lake waterlevels in the simulation model.As a first step we have built a vertically integrated St. Venant shallow water model to look at theeffects of bottom topography on large-scale flow patterns and the water level variation. TheCOMSOL® coefficient form PDE represents streamline artificial viscosity, Coriolis forces, andbottom friction, with boundary conditions representing river in- and outflow. The topographymodel must have continuous gradients, and a combination of Kriging with Delaunay triangulationis used to produce the surface model. Results of the long-time simulations will be presented aswell as numerical experiments with other approximate flow models to represent the moving watersurface.

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  • 2357.
    Pdungsilp, Aumnad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Service and Energy Systems.
    Martinac, Ivo
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Service and Energy Systems.
    Alessandro, Magny
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Service and Energy Systems.
    Energy system and service optimization for building clusters of new urban development: Applying multi-objective genetic algorithmsManuscript (preprint) (Other academic)
  • 2358.
    Pdungsilp, Aumnad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Service and Energy Systems.
    Martinac, Ivo
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Service and Energy Systems.
    Ngo, Tuan
    University of Melbourne.
    A Framework for Integrated Energy Systems, Infrastructure, and Services Optimization with Visualization and Simulation Platform for Low-carbon Precincts2013In: Proceedings of the International Symposium for Next Generation Infrastructure, 1 - 3 October 2013, 2013Conference paper (Refereed)
    Abstract [en]

    The energy informatics can be enhanced to support decision-making, communication and benchmarking of the energy performance both in design and operational phases. To enable engineers, developers and policy-makers to better understand the implications of energy systems and services, computer-generated visualization is a powerful tool to inform a range of technological options and to analyze the effects of energy system strategies. Visualization increases the transparency of results and the understanding of interactions between users and energy systems. This paper presents a novel conceptual framework for integrating energy systems, infrastructure and services optimization with a visualization and simulation platform. It focuses on the development of a tool for low-carbon energy systems and high quality energy services at precinct scale. The paper describes the vision and architectural design for the integrated framework. It is expected to serve as a next generation approach to managing energy services, carbon emissions and efficient resource use in the built environment. This will help to deliver new environmentally sustainable infrastructure and achieve carbon neutrality in urban development.

  • 2359.
    Pedrouso, A.
    et al.
    Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa de Lope Gómez de Marzoa s/n, Santiago de Compostela, Galicia E-15782, Spain.
    Trela, Jozef
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Val del Rio, A.
    Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa de Lope Gómez de Marzoa s/n, Santiago de Compostela, Galicia E-15782, Spain.
    Mosquera-Corral, A.
    Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa de Lope Gómez de Marzoa s/n, Santiago de Compostela, Galicia E-15782, Spain.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Performance of partial nitritation-anammox processes at mainstream conditions in an IFAS system2019In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 250, article id 109538Article in journal (Refereed)
    Abstract [en]

    The partial nitritation-anammox processes implementation in the main line of wastewater treatment plants would lead them closer to the energy autarky. With this purpose, an integrated fixed film activated sludge (IFAS) reactor was operated at pilot scale. Efficient nitrogen removal (72 ± 11%) was achieved for anaerobically pre-treated municipal wastewater at low temperature (21 – 15 °C), with a nitrogen removal rate of 37 ± 3 g N/(m3·d) at 15 °C. The ammonium oxidizing bacteria were more abundant in the activated sludge, while anammox bacteria were primarily located in biofilm attached onto the carriers surface. Nitrite oxidizing bacteria (NOB) activity was similar between both fractions and its specific activity decreased more than that of other populations when the operating temperature was reduced. Furthermore, the IFAS operational strategy (aerobic/anoxic periods) allowed an efficient NOB activity suppression inside the reactor, which accounted only for the 10 – 20% of the maximum potential activity.

  • 2360.
    Pehrs, Malin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Hjort, Lina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Energiutvärdering av Undervisningshuset på Kungliga Tekniska Högskolan i Stockholm: Uppföljning av energianvändning medelst normalårskorrigering2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The housing- and service sector makes up about 40 % of the total yearly energy use in Sweden. For new buildings with ambitious requirements, such as the object of this study, an important part of the work towards sustainability is follow-up and feedback on its energy use to illustrate the connection between ambition and actual result. Energy follow-up for Undervisningshuset, a building on KTH Campus with ambitious visions of sustainability and pedagogy, is therefore the aim of this study. To compare the energy use in buildings between different years the energy use must be normalized which is done in two steps; correction for normal occupancy and standard year correction. In this report the normalized energy use of Undervisningshuset is calculated by means of energy signature and degree-days, which is compared to the expected energy use according to the Energy Declaration normalized by SMHI’s energy-index. The energy performance of Undervisningshuset is 56 kWh/m2 and year according to the energy signature method and 59 kWh/m2 according to the degree-day method, compared to the expected energy performance in the Energy Declaration of 60 kWh/m2 and year. Both the results of this report and the Energy Declaration thereby classifies Undervisninshuset with Energy Class B.

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  • 2361.
    Pelletier, Nathan
    et al.
    Univ British Columbia Okanagan, Fipke Ctr Innovat Res, 3247 Univ Way, Kelowna, BC V1V 1V7, Canada..
    Bamber, Nicole
    Univ British Columbia Okanagan, Fipke Ctr Innovat Res, 3247 Univ Way, Kelowna, BC V1V 1V7, Canada..
    Brandao, Miguel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Interpreting life cycle assessment results for integrated sustainability decision support: can an ecological economic perspective help us to connect the dots?2019In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 24, no 9, p. 1580-1586Article in journal (Refereed)
    Abstract [en]

    Life cycle assessment (LCA) is often described as a sustainability decision support tool. In practice, however, the interpretation and application of most LCA studies are restricted to eco-efficiency considerations, which provide an important but incomplete basis for sustainability decision-making. Recent methodological advances in the field enable assessing LCA results against sustainability boundaries or thresholds at planetary or more finely resolved scales. Weighting, although controversial, facilitates consistent, stakeholder-appropriate decision-making that reflects prioritization among multiple and potentially competing sustainability outcomes. Here, we discuss how the three minimum necessary criteria for sustainability (i.e., sustainable scale relative to biocapacity, distributive justice, and efficient allocation), as proposed by ecological economist Herman Daly, may provide an internally consistent basis for integrating these methodological developments, and for subsequently better positioning LCA as a sustainability decision support framework.

  • 2362.
    Pena Balderrama, J. Gabriela
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Alfstad, Thomas
    United Nations Div Social & Econ Affairs, New York, NY 10001 USA..
    Taliotis, Constantinos
    Cyprus Inst, CY-2121 Nicosia, Cyprus..
    Hesamzadeh, Mohammad Reza
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electric Power and Energy Systems.
    Howells, Mark I.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    A Sketch of Bolivia's Potential Low-Carbon Power System Configurations. The Case of Applying Carbon Taxation and Lowering Financing Costs2018In: Energies, E-ISSN 1996-1073, Vol. 11, no 10, article id 2738Article in journal (Refereed)
    Abstract [en]

    This paper considers hypothetical options for the transformation of the Bolivian power generation system to one that emits less carbon dioxide. Specifically, it evaluates the influence of the weighted average cost of capital (WACC) on marginal abatement cost curves (MACC) when applying carbon taxation to the power sector. The study is illustrated with a bottom-up least-cost optimization model. Projections of key parameters influence the shape of MACCs and the underlying technology configurations. These are reported. Results from our study (and the set of assumptions on which they are based) are country-specific. Nonetheless, the methodology can be replicated to other case studies to provide insights into the role carbon taxes and lowering finance costs might play in reducing emissions.

  • 2363.
    Pena Balderrama, J. Gabriela
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Balderrama Subieta, S.
    Lombardi, F.
    Stevanato, N.
    Sahlberg, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Howells, M.
    Colombo, E.
    Quoilin, S.
    Incorporating high-resolution demand and techno-economic optimization to evaluate micro-grids into the Open Source Spatial Electrification Tool (OnSSET)2020In: Energy for Sustainable Development, ISSN 0973-0826, E-ISSN 2352-4669, Vol. 56, p. 98-118Article in journal (Refereed)
    Abstract [en]

    For decades, electrification planning in the developing world has often focused on extending the national grid to increase electricity access. This article draws attention to the potential complementary role of decentralized alternatives – primarily micro-grids – to address universal electricity access targets. To this aim, we propose a methodology consisting of three steps to estimate the LCOE and to size micro-grids for large-scale geo-spatial electrification modelling. In the first step, stochastic load demand profiles are generated for a wide range of settlement archetypes using the open-source RAMP model. In the second step, stochastic optimization is carried by the open-source MicroGridsPy model for combinations of settlement size, load demand profiles and other important techno-economic parameters influencing the LCOE. In the third step, surrogate models are generated to automatically evaluate the LCOE using a multivariate regression of micro-grid optimization results as a function of influencing parameters defining each scenario instance. Our developments coupled to the OnSSET electrification tool reveal an important increase in the cost-competitiveness of micro-grids compared to previous analyses.

  • 2364.
    Pena Balderrama, J. Gabriela
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis. UMSS, Bolivia.
    Broad, Oliver
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Sevillano, R. Carlos
    Alejo, Lucio
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Techno-economic demand projections and scenarios for the Bolivian energy system2017In: Energy Strategy Reviews, ISSN 2211-467X, E-ISSN 2211-4688, Vol. 16, p. 96-109Article in journal (Refereed)
    Abstract [en]

    Increasing energy access in emerging economies has played an important role to maintain or achieve desirable social and economic development targets. As a consequence, the growing energy requirements need policy instruments to ensure energy supply for future generations. The literature reports many studies with different approaches to model and test policy measures in the energy sector, however few energy-related studies for Bolivia are available. This paper addresses this knowledge gap, representing the first national level energy demand model and projections for Bolivia. The model use demographic, economic, technology and policy trends with a pragmatic model structure that combines bottom-up and top-down modelling. The scenario analysis has a particular focus on alternatives for energy savings, energy mix diversification and air quality. Three scenarios were analysed: Energy Savings, Fuel Substitution and the aggregate effects in a Combined scenario. The reference scenario results show the overall energy consumption grows 134% in 2035 compared to 2012 with an annual average growth of 3.8%. The final energy demand in the energy savings scenario is 8.5% lower than the Reference scenario, 1.5% lower in the fuel substitution scenario and 9.4% lower in the combined Scenario. The aggregate impact of both energy savings and fuel substitution measures leads to potential avoided emissions of 25.84 million Tons of CO2 equivalent in the model horizon 2012-2035.

  • 2365.
    Penaloza, Diego
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Royne, Frida
    RISE Res Inst Sweden, Gothenburg, Sweden..
    Sandin, Gustav
    RISE Res Inst Sweden, Gothenburg, Sweden..
    Svanstrom, Magdalena
    Chalmers Univ Technol, Div Environm Syst Anal, Gothenburg, Sweden..
    Erlandsson, Martin
    IVL Swedish Environm Res Inst, Stockholm, Sweden..
    The influence of system boundaries and baseline in climate impact assessment of forest products2019In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 24, no 1, p. 160-176Article in journal (Refereed)
    Abstract [en]

    PurposeThis article aims to explore how different assumptions about system boundaries and setting of baselines for forest growth affect the outcome of climate impact assessments of forest products using life cycle assessment (LCA), regarding the potential for climate impact mitigation from replacing non-forest benchmarks. This article attempts to explore how several assumptions interact and influence results for different products with different service life lengths.MethodsFour products made from forest biomass were analysed and compared to non-forest benchmarks using dynamic LCA with time horizons between 0 and 300years. The studied products have different service lives: butanol automotive fuel (0years), viscose textile fibres (2years), a cross-laminated timber building structure (50years) and methanol used to produce short-lived (0years) and long-lived (20years) products. Five calculation setups were tested featuring different assumptions about how to account for the carbon uptake during forest growth or regrowth. These assumptions relate to the timing of the uptake (before or after harvest), the spatial system boundaries (national, landscape or single stand) and the land-use baseline (zero baseline or natural regeneration).Results and discussionThe implications of using different assumptions depend on the type of product. The choice of time horizon for dynamic LCA and the timing of forest carbon uptake are important for all products, especially long-lived ones where end-of-life biogenic emissions take place in the relatively distant future. The choice of time horizon is less influential when using landscape- or national-level system boundaries than when using stand-level system boundaries and has greater influence on the results for long-lived products. Short-lived products perform worse than their benchmarks with short time horizons whatever spatial system boundaries are chosen, while long-lived products outperform their benchmarks with all methods tested. The approach and data used to model the forest carbon uptake can significantly influence the outcome of the assessment for all products.ConclusionsThe choices of spatial system boundaries, temporal system boundaries and land-use baseline have a large influence on the results, and this influence decreases for longer time horizons. Short-lived products are more sensitive to the choice of time horizon than long-lived products. Recommendations are given for LCA practitioners: to be aware of the influence of method choice when carrying out studies, to use case-specific data (for the forest growth) and to communicate clearly how results can be used.

  • 2366.
    Pereira Ramos, Eunice
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Advancing Nexus Approaches: insights from practice in support of their operationalisation2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The last decade has seen the emergence of a new research theme - the study of the resources Nexus. The “Nexus” refers to considering the functioning of several systems simultaneously, as opposed to one, as the object of research. This perspective reasons that coherent decision-making needs to consider systems' interconnectedness. Typical system-of-systems (Nexus) studied relate to the security of services, such as the Water-Energy and Food Nexus, and resources, i.e. the Climate, Land, Energy and Water systems (CLEWs) Nexus. The process of examining cross-systems dynamics and interactions is known as the Nexus approach. Implementing it requires understanding multiple systems, disciplinary integration, and multi-stakeholder engagement at various decision levels. Adequate planning of an assessment process is needed to ensure the successful implementation of the approach and its long-lasting presence in decision-making processes. Therefore, reviewing the application of Nexus approaches can inform essential aspects that clarify and streamline the entire process. Current gaps in Nexus research include the lack of clarity in systems representation, the lack of flexible and accessible tools and methods for Nexus analyses, and the need for transparency in modelling approaches. All of these hinder the integration of the approach in research and the incorporation into decision-making processes. 

    The thesis aims to advance the science of integrated resource assessments, particularly the Nexus approach, and support its dissemination and implementation within and beyond academia. Insights from applying two Nexus approaches (CLEWs and SIM4NEXUS) are distilled from the comparison of case studies. Overarching aspects examined include the expertise engaged in assessments, practitioners' roles and transdisciplinarity. Also analysed are selected components in the Nexus approach, such as identifying systems' interactions, analytical approaches, and stakeholder engagement and participation. The transversal feature of knowledge transfer between experts, practitioners, and stakeholders is examined to understand its importance in the assessment process. Examples of quantitative analyses illustrate the representation of different Nexus contexts and the elaboration of relevant insights. This thesis presents two such quantitative examples. One example is an entry-level CLEWs modelling exercise, whose development is described from conceptualisation, model development, and interpretation of results. The other example is a quantitative analysis of the transboundary Syr Darya river basin, which investigates the role of model structure in exploring Nexus questions. The thesis highlights a list of principles to support the Nexus approach's operationalisation deriving from practice and considering current research gaps.

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    Eunice_Ramos_PhD_Kappa
  • 2367.
    Pereira Ramos, Eunice
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Sridharan, Vignesh
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems. Imperial College London.
    Alfstad, Thomas
    United Nations Department of Economic and Social Affairs.
    Niet, Taco
    Simon Fraser University.
    Shivakumar, Abhishek
    United Nations Department of Economic and Social Affairs.
    Howells, Mark
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Loughborough University, Imperial College London.
    Rogner, Hans
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems. International Institute for Applied Systems Analysis (IIASA).
    Gardumi, Francesco
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Climate, Land, Energy and Water systems interactions – from key concepts to model implementation with OSeMOSYSManuscript (preprint) (Other academic)
    Abstract [en]

    The Climate, Land, Energy and Water systems (CLEWs) approach guides the development of integrated assessments. The approach includes an analytical component that can be performed using simple accounting methods, soft-linking tools, incorporating cross-systems considerations in sectoral models, or using one modelling tool to represent CLEW systems. This paper describes how a CLEWs quantitative analysis can be performed using one single modelling tool, the Open Source Energy Modelling System (OSeMOSYS). Although OSeMOSYS was primarily developed for energy systems analysis, the tool’s functionality and flexibility allow for its application to CLEWs. A step-by-step explanation of how climate, land and water systems can be represented with OSeMOSYS, complemented with the interpretation of sets, parameters, and variables in the OSeMOSYS code, is provided. A hypothetical case serves as the basis for developing a modelling exercise that exemplifies the building of a CLEWs model in OSeMOSYS. System-centred scenario analysis is performed with the integrated model example to illustrate its application. The analysis of results shows how integrated insights can be derived from the quantitative exercise in the form of conflicts, trade-offs, opportunities, and synergies. In addition to the modelling exercise, using the OSeMOSYS-CLEWs example in teaching, training and open science is explored to support knowledge transfer and advancement in the field.

  • 2368.
    Perennes, Marie
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Household plastic waste management in France: opportunities and barriers to niche innovations2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Due to their inherent properties including lightweight, versatility and low production costs, the production and use of plastic material is continually growing. Packaging is the primary application of plastic materials and plastic packaging represent a significant part of overall household waste generation. For several years, the reduction and avoidance of the negative impacts of waste on the environment and public health has been of major importance to the European Union environmental policies, with a long‐term vision to moving towards a recycling society. Yet, almost half of all postconsumer plastic packaging waste is still landfilled in France. Recently, a new national legislation has been implemented, with more strict recycling objectives, which should imply changes within the plastic waste management regime.

    Several technologies for plastic waste recycling are available, which can be broadly categorized into mechanical recycling and chemical recycling. However, the implementation of these technologies is influenced by the technological trajectory of the national waste management regime. The purpose of this thesis is to lead to a better understanding of the mechanisms of the technological diffusion and transition processes within the regime, through the identification of the main factors impeding or driving the dispersion of these treatment techniques. The Multi-Level Perspective framework was used in order to address this question. This analyse includes a  description of the regime’s trends, tensions and characteristics, the identification and characterization of the main promising innovations and plastic recycling filières, the identification of the landscape key factors and the assessment of the development of the main niches at the regime level.

    This analyse reveals that the main innovations barriers are: the institutional, economical and technological dimensions, which provide inertia to the regime through a network of actors relatively indisposed to major changes, allow economical viability of recycling processes and investments in this field, and the historically predominance of landfill and incineration options and (more recently) mechanical recycling technologies.

    The main opportunities leading to potential windows of opportunities for innovation development are: the sustainability dimensions and security/affordability of the raw material supply concerns throughout the stakeholders, which have influenced a broad range of dimensions at the regime level, such as policy, cultural, financial and market dimensions. As the raw material supply price is increasing, recycling processes can become more commercially viable. The sustainability dimensions and the growing European harmonization over regulations have led to more strict national recycling objectives, which can provide windows of opportunities for radical recycling innovations.

    The results of this thesis could be used as a basis for policy recommendations as it provides a broad picture of the plastic waste management, with the main mechanisms involved and factors that have stimulated the occurrence of technological transitions within the existing regime and barriers to their development. Policies can be adapted to exploit‘ windows of opportunities’ and relax barriers for the development of alternative filières highlighted in this work. However, the system seems to be‘ locked in’ at multiple dimensions, mainly institutional and technological. These locks in would limit the influence of the policy dimension on waste management and therefore make the management of technological transitions difficult to achieve.

     

  • 2369.
    Pereverza, Kateryna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Steering sustainability transitions? Modular participatory backcasting for strategic planning in the heating and cooling sector2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fostering sustainability transitions in the heating and cooling sector is a necessary and urgent issue. Steering mechanisms can enable coordination of actions by different actors towards common sustainability goals. Previous studies have identified requirements relevant for such steering frameworks, but have not specifically addressed planning in the highly contextual heating and cooling sector. Participatory backcasting (PB) possesses a number of relevant characteristics for use as a planning framework in this sector, but its adaptability and potential impact first need to be addressed.

    This thesis sought to advance strategic planning in the heating and cooling sector by improving the adaptability, transparency and reflexivity of PB processes and extending their impact beyond individuals directly involved, so-called social scales of impact. Key research objectives of the present work were to: (1) develop a strategic planning framework for the heating and cooling sector based on PB and examine its adaptability to local contexts, (2) develop methods for scenario development, selection and analysis to allow for co-informing between modelling and participatory processes within PB-based strategic planning, and (3) identify factors that could influence the social scales of the impact of participatory strategic planning processes.

    Objectives 1 and 2 were pursued in a multiple case study involving transdisciplinary research over one-year PB-based planning processes in Bila Tserkva, Ukraine (Case I) and Niš, Serbia (Case II). The social scales of impact (Objective 3) were studied in a single case – a Swedish project aimed at advancing the practice of long-term planning in regions ‘Region 2050’ (Case III). In all cases, both theoretical and empirical research were conducted.

    The study proposes a novel framework, modular participatory backcasting (mPB), for strategic planning in the heating and cooling sector. The framework integrates principles of modularity, participatory modelling, and transdisciplinarity. The results of mPB implementation in Case I and Case II suggest that the framework has acceptable adaptability to local contexts. Greater reflexivity and transparency in the scenario development, selection and analysis were achieved by developing a morphological method and implementation of participatory modelling approaches. Finally, boundary spanning individuals, collaborations and institutional plurality were identified in Case III as important factors for broadening the social scales of impact of participatory strategic planning processes.

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    Ph D Thesis
  • 2370.
    Pereverza, Kateryna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Lazarevic, David
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology. Finnish Environment Institute SYKE.
    Pasichnyi, Oleksii
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Kordas, Olga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Insights from participatory backcasting for a sustainable heating sector in Niš, Serbia2016Conference paper (Other academic)
  • 2371.
    Pereverza, Kateryna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Pasichnyi, Oleksii
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Kordas, Olga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Modular participatory backcasting: A unifying framework for strategic planning in the heating sector2019In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 124, p. 123-134Article in journal (Refereed)
    Abstract [en]

    This study proposes a novel framework, modular participatory backcasting (mPB), for long-term planning in the heating sector. The mPB framework is based on participatory backcasting (PB) and integrates principles of modularity, participatory modelling, and transdisciplinarity. We discerned for mPB 13 modules that can be arranged according to the purpose and specifics of each planning process. The design of the mPB framework and its implementation are presented for the cases of participatory strategic planning processes to achieve sustainable heat provision by 2050 in a Ukrainian city (Bila Tserkva) and a Serbian city (Nis). The results show that mPB allows adaptability to local contexts and limitations through exclusion, augmentation, substitution, splitting and inverting properties of modularity; decreases the learning time for applying the framework in a novel context; increases the reproducibility and transparency of long-term energy planning processes; enables efficient integration of quantitative methods into the participatory process; and advances collaboration between academia and society. The proposed framework is beneficial for advancement of local planning and policy-making practices by creating strategies with a wider support of stakeholders. It could also be useful for further research through cross-case analysis.

  • 2372.
    Pereverza, Kateryna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Pasichnyi, Oleksii
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Lazarevic, David
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Kordas, Olga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Developing urban energy scenarios - morphological analysis in the participatory backcasting framework2015In: Energy and Urban systems / [ed] Kordas and Ulgiati, Stockholm, 2015, p. 235-243Conference paper (Other academic)
  • 2373.
    Pereverza, Kateryna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Pasichnyi, Oleksii
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Lazarevic, David
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology. Environmental Policy Centre, Finnish Environment Institute SYKE.
    Kordas, Olga
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Strategic planning for sustainable heating in cities: A morphological method for scenario development and selection2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 186, no Part 2, p. 1115-1125Article in journal (Refereed)
    Abstract [en]

    The transition to more sustainable heating systems requires socio-technical approaches to strategic planning. Scenario development plays a key role in strategic planning, as the process supports the development of future visions and actions required for their realisation. However, new approaches to scenario development are required to address the limitations of conventional scenario development methods, such as the cognitive barriers of ‘groupthink’, reluctance to consider ‘outside-the-box’ options, handling of complexity, and ad hoc scenario selection and general non-transparency of scenario development processes. This paper describes the development and implementation of a novel method for scenario development and selection in the context of participatory strategic planning for sustainable heating in cities. The method is based on the morphological approach and a number of scenario criteria including transparency,reliabilitycoveragecompletenessrelevance/densitycreativityinterpretabilityconsistencydifferentiation and plausibility. It integrates creativity workshops and interdisciplinary stakeholder participation to enhance the ownership and legitimacy of the scenarios. The approach entails the generation of a complete space of scenarios for heating systems and reduction of this space using cross-consistency analysis and project-specific requirements. Iterative development and implementation of the method is illustrated using two participatory backcasting projects focused on strategic planning for providing a comfortable indoor climate for Bila Tserkva, Ukraine, and Niš, Serbia by the year 2030. The results demonstrate that the method helps overcome the limitations of conventional approaches to scenario development and supports rigorous and transparent selection of a scenario set for participatory analysis. The method fostered the elicitation of consensus-based scenarios for more sustainable heating systems in both cities with regard to the quality of indoor comfort, environmental impact, resource efficiency and energy security.

  • 2374.
    Perez Garcia, Adriana
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Techno-economic feasibility study of a small-scale biogas plant for treating market waste in the city of El Alto2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Every day 493 tonnes of waste containing 67% of organic material is generated in the city of El Alto in Bolivia. The majority of the waste is disposed to a landfill that is expected to reach its maximum capacity by 2015. Therefore, new waste treatment methods need to be explored. The high content of organic material in waste makes biogas technologies a potential solution for waste treatment in El Alto. These technologies can generate a renewable energy source and organic fertilizer that can provide several benefits to the city. The objective of this study is to investigate the techno-economic feasibility of a small-scale biogas plant for treating organic market waste in the city of El Alto. To this end, a multi-criteria analysis was performed to identify a suitable technology. The garage-shaped digester was selected as the most appropriate technology for the conditions of El Alto. By implementing this technology, 1.8 GWh of electricity and 2,340 tonnes of organic fertilizer can be produced annually. Furthermore, an economic analysis of two scenarios was conducted. The Net Present Value (NPV), Internal Rate of Return, Payback time, Levelized Cost of Electricity (LCOE) and sensitivity analysis were evaluated. The biogas plant resulted economically viable in both cases. However, the LCOE estimated (0.17-0.26 USD/kWh) were very high in comparison to the LCOE from natural gas in Bolivia (0.026 USD/kWh). Regarding the sensitivity analysis, several parameters were evaluated from which the compost price was the most influential on changing the NPV. The study also included the estimation of the emission savings. A total of 900 tonnes of CO2/year could be avoided for producing electricity from biogas. Moreover, social benefits could also be generated such as new job opportunities. The use of a small-scale biogas plant for treating organic market waste in the city of El Alto is a cost-effective option. Though, it is fundamental that the government support the waste-to-biogas technologies by introducing economic mechanisms and promoting awareness to ensure the markets for both, biogas and organic fertilizer.

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    fulltext
  • 2375.
    Perkoulidis, G.
    et al.
    Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University of Thessaloniki, Greece.
    Papageorgiou, Asterios
    Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University of Thessaloniki, Greece.
    Karagiannidis, A.
    Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University of Thessaloniki, Greece.
    Kalogirou, S.
    SYNERGIA, Greece.
    Integrated assessment of a new Waste-to-Energy facility in Central Greece in the context of regional perspectives2010In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 30, no 7, p. 1395-1406Article in journal (Refereed)
    Abstract [en]

    The main aim of this study is the integrated assessment of a proposed Waste-to-Energy facility that could contribute in the Municipal Solid Waste Management system of the Region of Central Greece. In the context of this paper alternative transfer schemes for supplying the candidate facility were assessed considering local conditions and economical criteria. A mixed-integer linear programming model was applied for the determination of optimum locations of Transfer Stations for an efficient supplying chain between the waste producers and the Waste-to-Energy facility. Moreover different Regional Waste Management Scenarios were assessed against multiple criteria, via the Multi Criteria Decision Making method ELECTRE III. The chosen criteria were total cost, Biodegradable Municipal Waste diversion from landfill, energy recovery and Greenhouse Gas emissions and the analysis demonstrated that a Waste Management Scenario based on a Waste-to-Energy plant with an adjacent landfill for disposal of the residues would be the best performing option for the Region, depending however on the priorities of the decision makers. In addition the study demonstrated that efficient planning is necessary and the case of three sanitary landfills operating in parallel with the WtE plant in the study area should be avoided. Moreover alternative cases of energy recovery of the candidate Waste-to-Energy facility were evaluated against the requirements of the new European Commission Directive on waste in order for the facility to be recognized as recovery operation. The latter issue is of high significance and the decision makers in European Union countries should take it into account from now on, in order to plan and implement facilities that recover energy efficiently. Finally a sensitivity check was performed in order to evaluate the effects of increased recycling rate, on the calorific value of treated Municipal Solid Waste and the gate fee of the candidate plant and found that increased recycling efforts would not diminish the potential for incineration with energy recovery from waste and neither would have adverse impacts on the gate fee of the Waste-to-Energy plant. In general, the study highlighted the need for efficient planning in solid waste management, by taking into account multiple criteria and parameters and utilizing relevant tools and methodologies into this context

  • 2376. Perninge, M.
    et al.
    Lavenius, Jan
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Vanfretti, Luigi
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Approximating a post-contingency stable operation region in parameter space through time-domain simulation2013In: Proceedings of IREP Symposium: Bulk Power System Dynamics and Control - IX Optimization, Security and Control of the Emerging Power Grid, IREP 2013, IEEE , 2013Conference paper (Refereed)
    Abstract [en]

    Operating criteria for power systems, such as the (N - 1)-criterion, are often based on evaluating whether the system is vulnerable to a specific set of contingencies. Therefore, a major part of power system security is concerned with establishing regions in parameter space where the system is vulnerable to specific contingencies. In this article we exploit the possibility of using Monte Carlo simulations to build an approximation of the region, in parameter space, where the power system will remain stable following a given contingency.

  • 2377.
    Persson, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Food redistribution in Stockholm: A comparative analysis of two scenarios – with and without a food bank2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Food waste is a serious problem in today’s society. Functional food waste is going to waste treatment while people are suffering from food insecurity. Food redistribution in form of a central food bank which collects food waste at food companies and delivers it to social organizations is a measure to deal with this issue. Stockholm City Mission plans to start up a central food bank in Stockholm and it is this implementation that is of focus in this report. The purpose of this study is to compare two scenarios, with and without a food bank, and evaluate this food bank regarding the possibilities for reduced climate impacts and the economic outcomes of the involving actors (food companies, the central food bank and social organizations). The methods used are literature studies, interviews and a material flow analysis to be able to follow the flows of food through the redistribution system. The results found are that costs can be saved for the actors involved and whether the food bank will go with profit depends on the revenues that can be collected from the involved actors and external investors. Climate impacts are reduced as a result of the implementation, mainly in terms of that functional food waste avoids waste treatment and can be of use.

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    fulltext
  • 2378.
    Persson, C. -M
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Seltborg, Per
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Åhlander, A.
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Gudowski, Waclaw
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Chigrinov, S.
    Serafimovich, I.
    Bournos, V.
    Fokov, Y.
    Routkovskaia, C.
    Kiyavitskaya, H.
    Comparison of neutron kinetic parameters of the subcritical ads experiments Yalina and Yalina Booster2005Conference paper (Refereed)
    Abstract [en]

    Subcritical experiments, devoted to investigation of characteristics of accelerator-driven systems, have been constructed at the Joint Institute for Power and Nuclear Research - Sosny in Minsk, Belarus. Different methods for reactivity determination have previously been investigated in the thermal ADS experiment "Yalina", and recently, a coupled fast-thermal facility "Yalina Booster" was launched. This study presents the neutron kinetic characteristics of the Yalina and the new Yalina Booster setups, and points out some important differences. For the Yalina setup, neutron kinetic parameters, such as keff, α, βeff and Λ have been determined by Monte Carlo simulations and they have previously been verified experimentally. For Yalina Booster, these parameters have been estimated by Monte Carlo simulations in a preliminary study, and they will be verified in upcoming experiments.

  • 2379.
    Persson, Ellen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Waldheim, Gerd
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Spridningen av poly-och perfluorerade ämnen från skidvalla: En litteraturstudie om hur användningen av fluorvalla inom längdskidåkning påverkar mark och vatten2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals used for their water, grease, and dirt repellent properties. Today these substances are widespread due to their ability to spread through both air and water. PFAS are long-term persistent and have hazardous environmental impact. Among others, affecting the reproduction of animals and has been shown to accumulate in the food chain. One product containing PFAS that has recently gained attention is fluorinated ski wax, due to the ban imposed on fluorinated ski wax by the International Ski Federation (FIS) from the season 2021/2022. 

    To investigate how the use of ski wax containing PFAS spreads and affects the environment at areas with cross-country skiing, results from previous studies have been analyzed. The previous studies were located at cross-country ski areas in Oslo and Trondheim in Norway, Maine in the USA and at the location of the Swedish competition Vasaloppet. A map has also been made to visualize where in Sweden there might be areas who have been contaminated with per- and polyfluoroalkyl substances by the use of ski wax. To find the locations for these areas two different methods have been used. 

    The results of the previous studies shows that the use of fluorinated ski waxes gives higher local concentrations of PFAS at the locations of cross-country ski areas that are frequently used. However, it is still difficult to draw clear conclusions about how big the spread of PFAS contamination is, since the substances can be found in many different products and are easily spread. In the future there is a need for more studies and investigation to reach clearer conclusions. In addition, there is a need for more tests around different ski areas to see the impact that competitions have, but also how everyday skiing affects the spread of PFAS. 

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    fulltext
  • 2380. Persson, F.
    et al.
    Sultana, Razia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Suarez, M.
    Hermansson, M.
    Plaza, Elzbieta
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Wilén, B. -M
    Structure and composition of biofilm communities in a moving bed biofilm reactor for nitritation-anammox at low temperatures2014In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 154, p. 267-273Article in journal (Refereed)
    Abstract [en]

    It is a challenge to apply anaerobic ammonium oxidation (anammox) for nitrogen removal from wastewater at low temperatures. Maintenance of anammox- and aerobic ammonia oxidizing bacteria (AOB) and suppression of nitrite oxidizing bacteria (NOB) are key issues. In this work, a nitritation-anammox moving bed biofilm pilot reactor was operated at 19-10°C for 300d. Nitrogen removal was decreasing, but stable, at 19-13°C. At 10°C removal became unstable. Quantitative PCR, fluorescence in situ hybridization and gene sequencing showed that no major microbial community changes were observed with decreased temperature. Anammox bacteria dominated the biofilm (0.9-1.2×1014 16S rRNA copies m-2). Most anammox bacteria were similar to Brocadia sp. 40, but another smaller Brocadia population was present near the biofilm-water interface, where also the AOB community (Nitrosomonas) was concentrated in thin layers (1.8-5.3×1012 amoA copies m-2). NOB (Nitrobacter, Nitrospira) were always present at low concentrations (<1.3×1011 16S rRNA copies m-2).

  • 2381.
    Persson, Henry
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Evangelopoulos, Panagiotis
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Svanberg, Rikard
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Weihong, Yang
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Two-step pyrolysis of biomass to enhance the chemical stability of pyrolytic liquids2017In: European Biomass Conference and Exhibition Proceedings 2017, ETA-Florence Renewable Energies , 2017, Vol. 7, no 25thEUBCE, p. 1186-1189Conference paper (Refereed)
    Abstract [en]

    Aging of pyrolytic liquid during storage changes its chemical and physical properties. The reason for aging is the chemical instability of the liquid, which is not at thermodynamic equilibrium when quenched after pyrolysis. Compounds active in these reactions mainly derivatives from hemicellulose (e.g. acids and carbonyls). In this work, a two-step pyrolysis concept was investigated to separate these compounds in a lower temperature treatment step upstream a conventional pyrolyzer. Different temperatures of the lower temperature treatment was investigated with constant conditions of the conventional treatment. The total liquid yield derived did not vary from pyrolysis in one step. Results show that the two-step pyrolysis process significantly reduces the concentration of organic acids and carbonyls in the liquid product from the second pyrolyzer, which instead are found in the liquid from the lower temperature treatment. Also, the concentration of sugar derivatives from the second step treatment is increased with the temperature of the first step. However, a complete separation of aging active compounds is not possible without sacrificing partial fractions of others (lignin derivatives were found in the low-temperature treatment). By varying the temperature of the first step one can control the concentrations and the liquid yield from each step.

  • 2382.
    Persson, Johannes
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Westermark, Mats
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Phase change material cool storage for a Swedish Passive House2012In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 54, p. 490-495Article in journal (Refereed)
    Abstract [en]

    Passive Houses have gained popularity the last 10 years as a way of improving the energy efficiency in the housing stock. The combination of a highly insulating building envelope and large solar heat gains summertime can, however, result in excessive temperatures. The aim of this paper is to evaluate a comfort cooling strategy for attaining good indoor climate summertime while maintaining good energy efficiency. The studied strategy is a night cool storage with phase change material (PCM). To evaluate this, a Matlab code was used for the analysis of climate files along with the thermodynamical properties of PCM storages and then used with IDA Indoor Climate and Energy for building simulations. The building model is based on an actual Passive House in the district of Lambohov in Linköping, Sweden, where continuous logging of temperatures are available. Without comfort cooling the simulations show excessive temperatures summertime, which is consistent with the field measurements from the actual house. The results show that the PCM can remove a substantial share of the degree hours with excessive temperatures.

  • 2383.
    Persson, Johannes
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Westermark, Mats
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Phase change material cool storage in a Swedish passive house2011In: Proceedings of the 24th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, ECOS 2011, Nis University , 2011, p. 1884-1893Conference paper (Refereed)
    Abstract [en]

    Passive Houses have gained popularity the last ten years as a way of improving the energy efficiency in the housing stock. During the cold winter in Sweden, external heating are at times needed but a Passive House is limited to a maximum use of 14 W/m2 or around 68 kWh/m2*year for external heating, depending on the heating strategy and the climate zone. The challenge of avoiding external heating during the cold winter climate in Sweden has pushed the design of a Passive House in a direction where problems with excessive temperatures might occur summertime. The aim of this paper is to evaluate a comfort cooling strategy for attaining good indoor climate summertime while maintaining good energy efficiency. The studied strategy is a night cool storage with phase change material. To evaluate this, a Matlab code was used for the analysis of climate files along with the thermodynamical properties of PCM-storages and then used with IDA Indoor Climate for building simulations. The building model is based on an actual Passive House in the district Lambohov in Linköping, Sweden, where continuous logging of temperatures are available. Without comfort cooling the simulations show excessive temperatures summertime which is consistent with the field measurements from the actual house. The results show that the phase change material can be a part of the solution and replace a substantial share of the external cooling when removing excessive temperatures but can not provide sufficient cooling during the hottest part of the summer simulated in this paper.

  • 2384.
    Persson, Josefine
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Sellgren, Felicia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    KOLLABORATIV KONSUMTION I NORRA DJURGÅRDSSTADEN: Hur den delande ekonomin kan bidra till hållbar stadsutveckling2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Collaborative consumption is a kind of economy where people consume through sharing, hiring, swopping and borrowing. This report investigates how the sharing economy can be implemented and developed in urban areas by doing a case study over the Stockholm Royal Seaport (Norra Djurgårdsstaden). This district in Stockholm was chosen because it is an ongoing urban development project that focuses on sustainability. In the case study researches were made on how the City of Stockholm (the Stockholm municipality) uses collaborative consumption in the sustainability program of the Stockholm Royal Seaport, and also their plans for the future. Furthermore suggestions on how collaborative consumption could be developed in the district were presented. The purpose with this project was thus, with the use of the case study, to outline how collaborative consumption can contribute to ecological and social urban development.

    The result of this report shows that the City of Stockholm, and especially the district administration of Östermalm, already today works with different types of collaborative consumption in the Stockholm Royal Seaport. For example they have planned for urban framing, beekeeping, and car- sharing. The City of Stockholm also focuses on education and information to the inhabitants to inspire to more sustainable lifestyles and thereby changed consumption patterns. There are many opportunities to develop the sharing economy in the Stockholm Royal Seaport. For example they are planning for facilities for different kinds of trading, more sharing of transport and also swopping services between the inhabitants, such as babysitting, walk the dog, cooking, etc.

    The case study showed that planning for changed consumption patterns can be difficult for the local stakeholders. The reason is that such kind of planning can reduce people’s own choices and personal integrity. It can be controversial with planning that approaches controlling of people’s living habits, but at the same time people must change their lifestyles to be more sustainable. However, the sharing economy does not definitely bring more sustainability, but this study shows that there are positive effects by collaborative consumption, both ecological and social, and the sharing economy has potential to develop in urban areas. 

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  • 2385. Persson, Åsa
    et al.
    Jonsson, Daniel K.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Nilsson, L. J
    Nilsson, M
    Finnveden, Göran
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Kompletterande klimatmål med fokus på sektorsmål2007Report (Other (popular science, discussion, etc.))
  • 2386. Pervaiz, Salman
    et al.
    Deiab, Ibrahim
    Rashid, Amir
    Nicolescu, Mihai
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Influence of rake angle on the cutting energy when modeling the machining of Ti6Al4V2015In: 2015 10th International Symposium on Mechatronics and its Applications (ISMA), Institute of Electrical and Electronics Engineers (IEEE), 2015, article id 7373461Conference paper (Refereed)
    Abstract [en]

    The finite element based machining simulations have been used widely in industry and academia to analyze the machining process. These virtual machining simulations have advantages over the real machining experiments due to the immense potential of saving time and expenses. The simulation techniques are even more popular when machining difficult to cut materials such as titanium alloy (Ti6Al4V). In order to make machining process sustainable in nature, energy consumption during the cutting process should be optimized accordingly. The present study aims to provide an insight towards the relation of cutting energy with respect to the different cutting tool geometries. The study used finite element based simulations to investigate the effect of rake angle on the cutting energy. Based on the cutting energy outcomes different suggestions were made to minimize the cutting energy.

  • 2387. Petersen, Lovisa Eriksson
    et al.
    Singh, Archit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Biogas: En systemanalys av Solna Stads matavfallsprocess2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Global warming is a huge issue that humans have contributed to through over-exploitation of natural resources and extensive usage of fossil fuels. Now more than ever, we need to embrace a recycle thinking and reuse our waste, for example through producing biogas from our food waste. The purpose of this report was therefore to identify the energy usage and emissions resulting from the biogas chain which spans from Solna Stad to Uppsala Vatten. Furthermore, potential efficiency improvements were to be identified and proposed. This report focused mainly on the first part of the biogas chain that includes the collection of the food waste and the reloading process. Gathering of information was done through study visits, interviews and literature studies.

    The transports accounted for a large part of the emissions and energy use. A reduction of these can be achieved by switching to more environmental friendly fuels. The useful energy obtained was higher for the reference alternative compared to the biogas process. However, social benefits were obtained from the biogas in the form of a renewable fuel and environmentally friendly manure. The energy usage during the winter months was significantly higher in the reloading facility compared to the summer due to heat leakage. A reduction of this can be achieved by building an accompanying construction with a high speed door in front of the reloading facility. 

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  • 2388.
    Petersson, Albert
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Mobility-as-a-Service and Electrification of Transport: A Study on Possibilities and Obstacles for Mobility-as-a-Service in Stockholm and Implications for Electrification of Vehicles2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Increasing urbanization drives the need for cities to make transport more efficient, both to meet climate goals as well as creating an attractive living environment for its residents, with less congestion, noise and local pollution. As vehicles are increasingly electrified, further innovations will be needed in order to meet environmental, social and economic sustainability targets, and a more efficient use of vehicles and public transport is central in this endeavor. As new generations are increasingly multimodal and digitalization opens up for innovative concepts, the possibilities for innovations to meet these challenges increases. Against this backdrop, Mobility as a Service (MaaS) has emerged as a concept with the potential to increase sustainability and mobility in cities. MaaS is based on the goal to challenge private car ownership by gathering different mobility services in one application, thereby creating a service offering with the potential to be more attractive than car-ownership. However, many varieties of MaaS exists and intensive efforts are ongoing to understand how MaaS can work in practice. MaaS has been described as a phenomenon with potential to radically change how people move in the future. The purpose of this thesis has been to understand how MaaS can affect the electrification of sustainable cities, with a focus on e-mobility. Starting off by trying to understand barriers to increased car-sharing in Stockholm, possibilities and challenges for MaaS in the city is discussed and its potential effects on emobility there. Data has been collected through continuous evaluation and review of literature and conducted interviews with actors and stakeholders within traffic and sustainable mobility in Stockholm. The results have been analyzed from a sustainable innovation perspective to discuss opportunities and challenges for the development of MaaS and its impact on electrification of vehicles. Collected empirics indicate that Stockholm has good opportunities for facilitating MaaS in the future, mainly due to accessible and extensive public transport (PT). The success of MaaS largely depends on the understanding of the service among consumers and why increased attention and marketing is important. An actor’s logic in individually owning the customer contact to be able to improve a service offering can be an obstacle to the growth of future mobility platforms. This underlines the need for cooperation between involved players to create momentum for MaaS. At the same time, MaaS benefits from a wide range of underlying mobility services and progressive traffic planning. In this regard, the results indicate that there are a number of different instruments at a macro level that could facilitate the sharing services to be developed. A legal definition of car sharing is a first step to facilitate measures to stimulate MaaS. Measures that smooth the relationship between the private car and car sharing services can create momentum for these, for example through exemptions from congestion tax. Access to parking at reasonable costs appears to be a key enabler for flexible shared mobility services in the future, partly because it currently accounts for a large part of the costs, and partly because the degree of flexibility and accessibility is determined by access to parking. At the same time, tougher parking regulations for BRFs and companies have also created a market for mobility services. Long term, there is a consensus that the future of transport is electrified. However, the impact of shared services and MaaS is highly shaped by the technical development of vehicles. Ongoing electrification of vehicles highlights the need for charging infrastructure deployed at locations that fits the need of shared services. Also, the charging equipment and solutions has to be developed to fit the needs of shared services and have a shared customer in mind.

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  • 2389.
    Petschelt, Lydia
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    A Small Scale CLEW Analysis of the Cape Town Region: Estimating the Effects of Climate Change on the Water Provision2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The knowledge of the influences climate change can have on a regional scale is still very limited. Generally it is known that the climate, land use, energy and water resources are intertwined. The CLEW strategy focuses on an approach to quantify these interrelations. In South Africa, experiencing a fast development, water resources are vital for a continuous prosperous growth. Through a methodological approach the local impacts of climate change on water supply and demand for the City of Cape Town are analysed. The focus lies on the Theewaterskloof Dam in the Riviersonderend catchment. For this study, the future climate data are generated in MarkSim for different SRES scenarios. Using the Water Evaluation And Planning system simulation software WEAP the catchment of interest is modelled to estimate future variation in water availability. For all scenarios the findings are consistent with prior studies forecasting an increase in the annual mean temperatures and a decrease in the annual precipitation. The reduction in annual precipitation consequently leads to a decreased water availability in the Riviersonderend catchment. Despite of the fact that the water resources are likely to diminish, the fixed annual water demand supplied by the Theewaterskloof reservoir is expected to be covered in the future without limitations. 

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  • 2390. Peuportier, Bruno
    et al.
    Scarpellini, Sabina
    Glaumann, Mauritz
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Malmqvist, Tove
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Krigsvoll, Guri
    Wetzel, Christian
    Staller, Heimo
    Szalay, Zsuzsa
    Degiovanni, Valeria
    Stoykova, Evelina
    State of the art for use of LCA in building sector: Deliverable D2 of the project ENSLIC_BUILDING : Energy Saving through Promotion of Life Cycle Assessment in Buildings2009Report (Other academic)
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  • 2391.
    Peña Balderrama, Jenny Gabriela
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Exploring low-carbon development pathways for Bolivia - A model-based analysis focused on the energy sector2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Global emissions have continued to rise steadily at levels exceeding the 1.5°C climate stabilization target. Therefore, the increase in the average global temperature and climate change will be determined by how we handle greenhouse gas (GHG) emissions over the next years. Decarbonizing economic growth and development add pressure to all countries in the world, but even more pressure to low and middle-income countries planning to use their fossil fuel resources as a ‘leading sector’ to achieve growth. Low and middle-income countries have limited financial resources and often have to prioritize short-term development goals with immediate local co-benefits over mitigation and adaptation strategies with long-term gains. Reaching the climate stabilization/decarbonization goal will require large investments to decarbonize the energy sector, together with investments and policy measures to ensure resilience and adaptation to climate change.

    Bolivia has signaled its intent to eradicate poverty and achieve economic growth while preserving environmental sustainability by adopting the seventeen Sustainable Development Goals (SDGs). In line with SDG7, Bolivia aims to achieve universal access to electricity by 2025. Although electricity access has improved significantly with large investments in grid-extension and decentralized systems, currently 61% of the grid generation capacity and 93% of the decentralized generation capacity is fossil-fueled. Other sectors, such as the transport sector, depend mostly on fossil fuels and largely contribute to Bolivia’s GHG emissions. Policies intended to increase energy security in Bolivia focus on the increased use of domestic natural gas, on investments in large-scale hydropower plants, and on first-generation (1G) biofuel production for the transport sector.

    In line with SDG 7 and SDG 13, this doctoral thesis examines low-carbon development pathways for the main policies addressing energy access and energy security in Bolivia. With methods deriving from systems analysis, the particulars of the Bolivian energy system were scrutinized and the effects of alternative energy planning decisions ‒ such as policies and investments ‒ displayed using scenario analysis. Five research articles answering four research questions form the main part of the thesis.

    The first research question examines the role of decentralized technologies (primarily micro-grids) and renewable energy for addressing universal electricity access targets. The cost-competitiveness of multi-source micro-grids is assessed using an innovative methodology developed to increase the technical accuracy of load simulation and microgrid system design optimization in an existing geospatial modelling tool. The results highlight the potential of decentralized electrification solutions and identify the location, size and investments required to meet electrification targets in 2025.

    The second research question focuses on evaluating alternative policies for decarbonizing the power generation sector using an energy system optimization model. The combined effects of inserting carbon taxes and modifying the weighted average cost of capital on the power generation emissions are measured in marginal abatement cost curves. Results from this conceptual and numerical analysis show that a deep decarbonization of the power generation system requires very high carbon prices if the costs of capital are high. Instead, moderate carbon prices combined with low costs of capital can lead to significant emissions reductions and comparably smaller increases in carbon abatement costs.

    The third research question examines Bolivia’s hydroelectricity export plans in the medium-term using a cost-optimization model of South America. The study also evaluates the fair distribution of benefits using a cooperative game-theory approach and the decarbonization achieved in a scenario of power systems integration in South America. Results of this study indicate that electricity from large-scale hydropower projects could be traded with Brazil and reduce Bolivia’s dependence on natural gas for power generation. The results also show that Bolivia has less bargaining power than its competitors have in the long-term and benefits less from emissions reductions in a scenario of trade with Brazil.

    Lastly, the fourth research question explores energy security in the transport sector by assessing Bolivia’s sugarcane-based ethanol production targets. Increased sustainability in the ethanol production chain is evaluated quantitatively by identifying opportunities for agricultural intensification and investments in advanced biorefineries in a least-cost optimization model. Results from this analysis demonstrate that Bolivia can cost-effectively reach its medium-term targeted volumes of ethanol production with a moderate expansion of sugarcane cropland and investments in agriculture intensification. The results further suggest that it is cost-optimal to invest in current technological advances (i.e. efficient co-generation plants) to maximize the renewable energy output and the economic benefits of sugarcane-derived ethanol. Finally, the study identifies a range of biofuel-support incentives to promote investments in second-generation biofuel production.

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    Gabriela Pena Balderrama_DoctoralThesis 2020
  • 2392.
    Peña Balderrama, Jenny Gabriela
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Khatiwada, Dilip
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Gardumi, Francesco
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Alfstad, Thomas
    United Nations Division of Social and Economic Affairs.
    Ulloa Jimenez, Silvia
    Stockholm Environment Institute.
    Howells, Mark I.
    Integrated analysis of land-use, energy and water systems for ethanol production from sugarcane in BoliviaManuscript (preprint) (Other academic)
    Abstract [en]

    The use of biomass for renewable energy production is one alternative to reduce the environmental impacts of energy production worldwide. Sugarcane-based ethanol is one of the most widespread biofuels in the road transport sector and its development has been encouraged by strong incentives on production and use in several countries. The growing realization on the environmental impacts of ethanol production indicates the need to increase the efficient utilization of biomass resources by optimizing the production chain sustainably. This paper evaluates enhancements in the ethanol production chain quantitatively by identifying opportunities for agricultural intensification and investments in advanced biorefineries in a least-cost optimization model. Results of our model show that significant cost and environmental benefits can be achieved by modernizing sugarcane agriculture in Bolivia. Demands for ethanol and sugar can be met cost-effectively by increasing sugarcane yields from the current country-average of 55.34 ton/ha to 85.7 ton/ha in 2030 with a moderate cropland expansion of 11.4 thousand hectares in the period 2019-2030. Our results further suggest that it is cost-optimal to invest in efficient cogeneration in biorefineries to maximize the renewable energy output and the economic benefits of sugarcane ethanol. Finally, biofuel support in the range of 8-10 US$/GJ is required for investments in second-generation ethanol in biorefineries to be cost-competitive in the medium-term.

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  • 2393.
    Peñaloza, Diego
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials. RISE - Research Institutes of Sweden.
    Future scenarios for climate change mitigation of new building construction in Sweden: Effects of different technological pathwaysManuscript (preprint) (Other academic)
    Abstract [en]

    Climate mitigation strategies are required with urgency. The Swedish construction sector contributes to a significant share of the country’s yearly greenhouse gas (GHG) emissions. A variety of alternative climate mitigation strategies is available aimed to different processes and activities related to production and operation of buildings. Several studies evaluating the effectiveness of these strategies have been performed at the building stock level. These studies however do not consider the technological change in manufacturing of building materials. The objective of this study is to evaluate the climate change mitigation effects of increasing the use of biobased materials in the construction of new residential buildings in Sweden under different scenarios related to technological change in material manufacturing. For this, the climate impact from Swedish new buildings has been assessed for the coming one hundred years using a model that combines scenario analysis based on official statistics and life cycle assessment of seven different building typologies. Eight different scenarios for increased use of low-impact building typologies such as timber buildings and low-impact concrete are explored under different pathways for growth of their market share and changes in energy production. The results show that the benefits from an increased use of biobased materials are significant in all scenarios evaluated, but decrease if the use of low-impact concrete expands more rapidly or under optimistic scenarios for energy production. Results are also highly sensitive to the choice of climate impact metric. Results also show that the Swedish construction sector can only reach maximum climate change mitigation scenarios if all the low-impact typologies are implemented together and rapidly, including a rapid switch to cleaner energy.

  • 2394.
    Peñaloza, Diego
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials. RISE - Research Institutes of Sweden.
    The influence of system boundaries and baseline in climate impact assessment of forest productsManuscript (preprint) (Other academic)
    Abstract [en]

    Purpose

    This article aims to explore how different assumptions about system boundaries and setting of baselines for forest growth affect the outcome of climate impact assessments of forest products during life cycle assessment (LCA), including potential climate impact mitigation from replacing non-forest benchmarks. This article attempts to explore how several assumptions interact and influence results for different products with different service life lengths.

    Methods

    Four products made from forest biomass were analysed and compared to non-forest benchmarks using dynamic LCA with time horizons between 0 and 300 years. The studied products have different service lives: butanol automotive fuel (0 years), viscose textile fibres (2 years), a cross-laminated timber building structure (50 years) and methanol used to produce short-lived (0 years) and long-lived (20 years) products. Five calculation setups were tested featuring different assumptions about how to account for the carbon uptake during forest growth or regrowth. These assumptions relate to the timing of the uptake (before or after harvest), the spatial system boundaries (national, landscape and single stand approaches) and the land use baseline (zero baseline and natural regeneration).

    Results and discussion

    The implications of using different assumptions depend on the type of product. The choice of time horizon for dynamic LCA and the timing of forest carbon uptake are important for all products, especially long-lived ones where end-of-life biogenic emissions take place in the relatively distant future. The choice of time horizon is less influential when using landscape or national spatial boundaries than when using a stand approach, but has great influence on the results for long-lived products. The influence of the methodological choices studied in the comparison of the products with their benchmarks has divergent outcomes. Short-lived products perform worse than their benchmarks with short time horizons whatever spatial boundaries are chosen, while long-lived products outperform their benchmarks with all methods tested.

    Conclusions

    The choices of spatial boundaries, temporal boundaries and land use baseline have a large influence on the results, but this influence decreases for longer time horizons. Short-lived products are more sensitive to the choice of time horizon than long-lived products. Recommendations are given for LCA practitioners: to be aware of the influence of method choice when carrying out studies, to prioritise case-specific data for forest growth and to communicate clearly how results should be used and interpreted.

  • 2395.
    Peñaloza, Diego
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials. RISE - Research Institutes of Sweden.
    The role of biobased building materials in the climate impacts of construction: Effects of increased use of biobased materials in the Swedish building sector2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A significant share of the global climate change impacts can be attributed to the construction sector. One mitigation strategy is increasing the use of biobased materials. Life cycle assessment (LCA) has been used to demonstrate the benefits of this, but forest complexities create uncertainty due to omission of key aspects. The aim of this thesis is to enhance understanding of the effects of increasing use of biobased materials in climate change mitigation of construction works with a life cycle perspective. Non-traditional LCA methodology aspects were identified and the climate impact effects of increasing the use of biobased materials while accounting for these was studied. The method applied was dynamic LCA combined with forest carbon data under multi-approach scenarios. Diverse case studies (a building, a small road bridge and the Swedish building stock) were used. Most scenarios result in impact reductions from increasing the use of biobased materials in construction. The inclusion of non-traditional aspects affected the results, but not this outcome. Results show that the climate mitigation potential is maximized by simultaneously implementing other strategies (such as increased use of low-impact concrete). Biobased building materials should not be generalised as climate neutral because it depends on case-sensitive factors. Some of these factors depend on the modelling of the forest system (timing of tree growth, spatial level approach, forest land use baseline) or LCA modelling parameters (choice of the time horizon, end-of-life assumptions, service life). To decrease uncertainty, it is recommended to use at least one metric that allows assessment of emissions based on their timing and to use long-term time horizons. Practitioners should clearly state if and how non-traditional aspects are handled, and study several methodological settings. Technological changes should be accounted for when studying long-term climate impacts of building stocks.

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  • 2396.
    Peñaloza, Diego
    et al.
    KTH. RISE Res Inst Sweden, Eklandagatan 86, S-41261 Gothenburg, Sweden.
    Erlandsson, Martin
    IVL Swedish Environm Res Inst, Valhallavagen 8, S-11427 Stockholm, Sweden..
    Berlin, Johanna
    RISE Res Inst Sweden, Eklandagatan 86, S-41261 Gothenburg, Sweden..
    Wålinder, Magnus
    KTH.
    Falk, Andreas
    KTH.
    Future scenarios for climate mitigation of new construction in Sweden: Effects of different technological pathways2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 187, p. 1025-1035Article in journal (Refereed)
    Abstract [en]

    A variety of climate mitigation strategies is available to mitigate climate impacts of buildings. Several studies evaluating the effectiveness of these strategies have been performed at the building stock level, but do not consider the technological change in building material manufacturing. The objective of this study is to evaluate the climate mitigation effects of increasing the use of biobased materials in the construction of new residential dwellings in Sweden under future scenarios related to technological change. A model to estimate the climate impact from Swedish new dwellings has been proposed combining official statistics and life cycle assessment data of seven different dwelling typologies. Eight future scenarios for increased use of harvested wood products are explored under different pathways for changes in the market share of typologies and in energy generation. The results show that an increased use of harvested wood products results in lower climate impacts in all scenarios evaluated, but reductions decrease if the use of low-impact concrete expands more rapidly or under optimistic energy scenarios. Results are highly sensitive to the choice of climate impact metric. The Swedish construction sector can only reach maximum climate change mitigation scenarios if the low-impact building typologies are implemented together and rapidly.

  • 2397.
    Peñaloza, Diego
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials. RISE - Research Institutes of Sweden.
    Erlandsson, Martin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Pousette, Anna
    Climate impacts from road bridges: effects of introducing concrete carbonation and biogenic carbon storage in wood2018In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 14, no 1, p. 56-67Article in journal (Refereed)
    Abstract [en]

    The construction sector faces the challenge of mitigating climate change with urgency. Life cycle assessment(LCA), a widely used tool to assess the climate impacts of buildings, is seldom used for bridges. Materialspecificphenomena such as concrete carbonation and biogenic carbon storage are usually unaccountedfor when assessing the climate impacts from infrastructure. The purpose of this article is to explore theeffects these phenomena could have on climate impact assessment of road bridges and comparisonsbetween bridge designs. For this, a case study is used of two functionally equivalent design alternativesfor a small road bridge in Sweden. Dynamic LCA is used to calculate the effects of biogenic carbon storage,while the Lagerblad method and literature values are used to estimate concrete carbonation. The resultsshow that the climate impact of the bridge is influenced by both phenomena, and that the gap betweenthe impacts from both designs increases if the phenomena are accounted for. The outcome is influencedby the time occurrence assumed for the forest carbon uptake and the end-of-life scenario for the concrete.An equilibrium or 50/50 approach for accounting for the forest carbon uptake is proposed as a middlevalue compromise to handle this issue.

  • 2398. Pfenninger, Stefan
    et al.
    Hirth, Lion
    Schlecht, Ingmar
    Schmid, Eva
    Wiese, Frauke
    Brown, Tom
    Davis, Chris
    Gidden, Matthew
    Heinrichs, Heidi
    Heuberger, Clara
    Hilpert, Simon
    Krien, Uwe
    Matke, Carsten
    Nebel, Arjuna
    Morrison, Robbie
    Mueller, Berit
    Plessmann, Guido
    Reeg, Matthias
    Richstein, Joern C.
    Shivakumar, Abhishek
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Staffell, Iain
    Trondle, Tim
    Wingenbach, Clemens
    Opening the black box of energy modelling: Strategies and lessons learned2018In: Energy Strategy Reviews, ISSN 2211-467X, E-ISSN 2211-4688, Vol. 19, p. 63-71Article in journal (Refereed)
    Abstract [en]

    The global energy system is undergoing a major transition, and in energy planning and decision-making across governments, industry and academia, models play a crucial role. Because of their policy relevance and contested nature, the transparency and open availability of energy models and data are of particular importance. Here we provide a practical how-to guide based on the collective experience of members of the Open Energy Modelling Initiative (Openmod). We discuss key steps to consider when opening code and data, including determining intellectual property ownership, choosing a licence and appropriate modelling languages, distributing code and data, and providing support and building communities. After illustrating these decisions with examples and lessons learned from the community, we conclude that even though individual researchers' choices are important, institutional changes are still also necessary for more openness and transparency in energy research.

  • 2399.
    Pham, Cong-Toan
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electromagnetic Engineering.
    Månsson, Daniel
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electromagnetic Engineering.
    Assessment of energy storage systems for power system applications via suitability index approach (Part IV)2019In: Journal of Energy Storage, ISSN 2352-152X, E-ISSN 2352-1538, Vol. 24, article id 100777Article in journal (Refereed)
    Abstract [en]

    Energy storage systems provide several benefits and services in optimizing the power grid's reliability, efficiencyand safety. However, the feasibility of energy storage systems varies dependent on the requirements of theapplications. Technical limitations in design and type of the storage technology prevents a single storage type toperform equally well in all situations. Hence, it is essential to compare and measure the energy storages’ usefulnessand determine their optimal use. To address this issue this study introduces an indexing approach toevaluate the suitability of energy storages for power system applications. Four different energy storages (doublelayercapacitor, flywheel, lead–acid battery, lithium-ion battery) are tested for four typical energy storage applications(frequency regulation, voltage support, capacity firming and energy time-shift). The suitability indexallows a simple and intuitive way to compare and rank the suitability of energy storages.

  • 2400.
    Pham, Cong-Toan
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electromagnetic Engineering.
    Månsson, Daniel
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electromagnetic Engineering.
    Experimental validation of a general energy storage modelling approach(Part III)2018In: Journal of Energy Storage, ISSN 2352-152X, E-ISSN 2352-1538, Vol. 20, p. 542-550Article in journal (Refereed)
    Abstract [en]

    Current challenges in the electric grid progression demand energy storages to cope with any imbalances betweensupply and demand side. Application possibilities of energy storages are numerous, but the requirements varyfrom case to case. However, not every storage technology operates equally to be useful in any situation. In fact,the feasibility of energy storages depend on their technical characteristics, i.e., for example efficiency, responsetimes, power rating and capacity for a selected application. Comparing and assessing different storage options isimperative for decision-making, which requires an in-depth understanding of the technology and its dynamics.Hence, a general model approach of energy storages as equivalent circuit models has been proposed to unify andanalyze storages of different physical backgrounds. This allows a more direct and intuitive evaluation of energystorages tested in a specific application. This paper focuses on the experimental validation of energy storages(ultra-capacitor, li-ion battery, lead-acid battery and flywheel) to be uniformly described in one general model. Asimple and budget friendly experimental setup to test the storages is designed.

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