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Quantifying the Potential Impact of Improved Stoves in Nyeri County, KenyaBoulkaid, Youssef January 2015 (has links)
Energy poverty is defined as the lack of access of households in developing countries to modern energy sources, and their consequent reliance on solid biomass fuels for cooking. So-called “Improved stoves” have been promoted by various public and private actors since the 1970s to tackle various environmental and health challenges associated with biomass use. Impact studies of such projects are usually based on on-site surveys about the stoves’ use, and thus are extremely site-specific, and difficultly generalizable. This thesis project aims to introduce a novel approach to impact assessment of improved cooking stoves on both local energy needs and deforestation in the area. This approach will base most of its figures and assumptions on calculated energy needs rather than survey reports. This will result in a highly flexible energy model, which can be used and adapted to help decision and policy makers in their function. The area of Nyeri County, Kenya, where the author completed a one-month field study, is used throughout the thesis as a case study in order to validate the model.
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Big Data Analytics towards a Retrofitting Plan for the City of Stockholmvan der Heijde, Bram January 2014 (has links)
This thesis summarises the outcomes of a Big Data analysis, performed on a set of hourly district heating energy consumption data from 2012 for nearly 15 000 buildings in the City of Stockholm. The aim of the study was to find patterns and inefficiencies in the consumption data using KNIME, a big data analysis tool, and to initiate a retrofitting plan for the city to counteract these inefficiencies. By defining a number of energy saving scenarios, the potential for increased efficiency is estimated and the resulting methodology can be used by other (smart) cities and policy makers to estimate savings potential elsewhere. In addition, the influence of weather circumstances, building location and building types is studied. In the introduction, a concise overview of the concepts Smart City and Big Data is given, together with their relevance for the energy challenges of the 21st century. Thereafter, a summary of the previous studies at the foundation of this research and a brief theory review of less common methods used in this thesis are presented. The method of this thesis consisted of first understanding and describing the dataset using descriptive statistics, studying the annual fluctuations in energy consumption and clustering all consumer groups per building class according to total consumption, consumption intensity and time of consumption. After these descriptive steps, a more analytical part starts with the definition of a number of energy saving scenarios. They are used to estimate the maximal potential for energy savings, regardless of actual measures, financial or temporal aspects. This hypothetical simulation is supplemented with a more realistic retrofitting plan that explores the feasibility of Stockholm’s Climate Action Plan for 2012-2015, using a limited set of energy efficiency measures and a fixed investment horizon. The analytical part is concluded with a spatial regression that sets out to determine the influence of wind velocity and temperature in different parts of Stockholm. The conclusions of this thesis are that the potential for energy savings in the studied data set can go up to 59% or 4.6 TWh. The financially justified savings are estimated at ca. 6% using favourable investment parameters. However, these savings quickly diminish because of a high sensitivity on the input parameters. The clustering analysis has not yielded the anticipated results, but they can be used as a tool to target investments towards groups of buildings that have a high return on investment.
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Techno-economic Analysis of Combined Hybrid Concentrating Solar and Photovoltaic Power Plants: a case study for optimizing solar energy integration into the South African electricity gridCastillo Ochoa, Luis Ramon January 2014 (has links)
The cooperation between large scale Concentrated Solar Power plants (CSP) and Solar Photovoltaic (PV) parks can offer stability in power supply and enhance the capacity factor of the CSP plant intended to cover a common demand on the power system. Moreover, it can offer an investment option with lower risk. This Master thesis project presents optimum plant configurations for both technologies under the same meteorological and market conditions. The study is based in the South African electricity market and the Renewable Energy Independent Power Producer Program currently in place in the country. Using MATLAB and TRNSYS softwares, a series of detailed codes were designed in order to model both technologies energy transformation process. The main approach was to design the nominal operation point of both technologies for a given typical meteorological year data and respective technical conditions for each case. Then, a transient simulation was done in order to obtain the electricity yield. The intention was to measure the internal rate of return, levelized cost of electricity and capacity factor for each technology and the combined configuration (CSP-PV plant) under different scenarios and operation modes while a firm capacity was maintained. It was found that the plants can be economically feasible by sizing a storage unit capable of just covering the peak hours. The solar multiple sizes can vary depending on the scenario and plant configuration. Moreover, the internal rate of return increases with the capacity of the CSP in all cases. After the results were obtained, a comparison with a single CSP plant and the optimum CSP-PV plant was done in order to evaluate the performance of the proposed cooperation. Even though the internal rate of return of the CSP-PV plant was found to be within a good range for investment, the CSP-alone alternative offered always higher internal rate of return and lower levelized cost of electricity values. Nonetheless, it was found that the capacity factor of the combined configuration was favored by the integration of PV. The PV alone configuration hold the lowest levelized cost of electricity, thus considered the best option for and investment in South Africa due to its independence towards incentives. Combined PV-CSP systems were also found to be an attractive investment under the South African scheme if the CSP capacity is similar to the PV power plant.
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Techno-economic feasibility study of a small-scale biogas plant for treating market waste in the city of El AltoPerez Garcia, Adriana January 2014 (has links)
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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Analys av en fysisk energigemenskap med solceller och batterilagring / Analyze of a physical energy community with PV-modules and battery storageGustafsson, Maria January 2022 (has links)
During the last years the number of installed PV-modules have increased significantly. As a result, the self-consumption of the solar electricity has become more important. One way to increase the self-consumption is to install an energy storage, for instance a battery. Another way is to introduce a physical energy community. An energy community is a way to share energy, in this case local produced renewable energy from the PV-panels, between buildings in a local electrical-grid. The aim of this project is to investigate how the self-consumption change when an energy community is introduced and explore differences depending on the heating system of the building. This energy community includes seven buildings, two buildings with district heating and five buildings with heat pumps. An economic analysis of the economic benefits of energy communities is also included. The project is conducted as a case study of a new block that is under construction in Örebro. A building simulation have been performed in IDA ICE 4.8 SP2. This includes simulations of energy consumption and energy production from PV-modules. The battery model is done in Matlab and used to simulate different battery sizes. The self-consumption increases when an energy community is established for all the individual buildings no matter of the heating method. For buildings with heat pump, the self-consumption was higher than it was for the buildings with distric-heating. The district heated building with the lowest self-consumption as an individual building increased its self-consumption from 66.7% to 72.5% when joining an energy community with only one other building. For building with heatpump the lowest self-consumption was 82.5% and in an energy community the self-consumption increased to 92.6% From an economic aspect it is a good idea to establish an energy community regardless of size and type of heating method that is used in the buildings. For all communities the repayment period for the PV-modules is shorter for the community than it is for the individual buildings. However, to install a battery for the community is not profitable if you only load the battery when there is an overproduction from the PV-modules compared to the need from the load.
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Investigation of Probable Pollution from Automobile Exhaust Gases in Kampala City, Uganda : To Assess the current automobile exhaust gas emission levels and characterize the emissions from different automobile typesBateebe, Irene January 2011 (has links)
It is estimated that transport sources in developing countries contribute about 4% of the global fossil carbon dioxide versus 18% by industrialized countries. The cost of urban air pollution is estimated to be 2% of GDP in developed countries and more than 5% in developing countries. With an annual vehicle registration growth of over 30% in 2008 and a population growth rate of 6%, the number of automobiles in Kampala city of Uganda is expected to continue growing exponentially. Most of the vehicles used are imported into the country when quite old with worn out engines and low energy efficiencies. As a result, such vehicles profusely emit exhaust gases which may be harmful to both human health and the environment. Controlling pollution from the transport sector is vital to improving the quality of air and protecting public health. The objective of this dissertation was to determine the level of pollution from automobile exhaust gases in Kampala City and its impacts on human health and the environment. The study involved the analysis of tail pipe emissions using a gas analyser. It covered mini buses, motorcycles and personal vehicles which constitute 92% of the Kampala vehicle parc. It was established that the main types of exhaust gases from the automobiles were CO2, NOx, CO, NO and HC. The findings estimated the highest level of NOx tail pipe emissions at 0.15 mg/m3, HC emissions at 2.59 mg/m3, CO at 110 mg/m3 and 286.6 mg/m3 for CO2. The reported ambient air emissions were estimated at 0.18 ppm, 14000 ppm and 1.3 ppm corresponding to NO2, CO2 and CO, respectively. The study further investigated the impact of four mitigation methods on emission levels using the LEAP model. The impact of increasing penetration of city buses, introduction of tail pipe emission standards and hybrid cars and improvement of vehicle fuel economy were investigated. It was found that if left unabated, the emissions will continue to grow with the increasing number of motor vehicles. Implementation of the proposed mitigation methods resulted in a reduction in the GWP reduced by 52%, 51%, 17% and 8.5%, respectively. It is recommended that a comprehensive motor vehicle pollution control program be designed to implement the proposed NEMA vehicle emission standards. Establishment of an integrated transport system promoting the growth in number of city buses should be made a priority to reduce on emission levels and enable the decongestion of Kampala city.
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CASE STUDY OF ACTIVE FREE COOLING WITH THERMAL ENERGY STORAGE TECHNOLOGYGravoille, Pauline January 2011 (has links)
May 25, 2011, Reuters’ headline read: "New York State is prepared for summerelectricity demand". The NY operator forecasts for next summer a peak of 33GW, close to therecord ever reached. With soaring cooling demands, the electricity peak load represents a substantialconcern to the energy system. In the goal of peak shaving, research on alternative solutions based onThermal Energy Storage (TES), for both cooling and heating applications, has been largely performed.This thesis addresses thermal comfort applications with use of active free cooling through implementationof latent heat based TES. Active free cooling is based on the use of the freshness of a source, the outsideair for example, to cool down buildings. This work conceptualizes the implementation of TES basedcooling system with use of Phase Change Material in an in-house-built model. The principle of PhaseChange Material, or Latent Heat TES (LHTES), lies on latent energy which is the energy required for thematerial to change phase. In order to properly size this cooling system, a multi-objective optimization isadopted. This optimization, based on minimization of multi-objective functions, led to optimal designconfigurations. In parallel, the electrical consumption of the system and the volume uptake of the systemwere also considered. Through the obtained optimization studies, we identified non-linearinterdependency between the two objective functions: the cost of the system and the acceptable remainingcooling needs. By remaining cooling needs, we mean the cooling needs that the system cannot meet. As amatter of fact, sizing the system according to these cooling needs would imply a very high cost. It wasfound that for a certain amount of remaining cooling needs, the PCM-based cooling system reveals to bean interesting solution compared to conventional air conditioning in terms of electrical consumption andoverall system cost. / Best Master Thesis Award, granted by French Academic Institute / Cold Thermal Energy Storage
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Energy Policy and development of Renewable Energy Sources for Electricity: A comparative analysis of the Swedish and Greek casesTsakiris, Iakovos - Marios January 2011 (has links)
Before electricity liberalization was implemented in the EU, national utilities controlled energy planningand technology choices and were basically the only ones with access to energy infrastructure finance.Liberalization came to change that. One of the goals of EU policies today is to create a level playing fieldfor power production based on new technologies and decentralized supply. However, institutional,structural and other barriers hinder further RES diffusion. Such barriers need to be alleviated to acceleratethe diffusion of RES technologies. This study analyses the Swedish and Greek experiences and actions inthe energy policy area between 2003 and 2008. I identify actions and evaluate their effects highlightingsimilarities and differences between the two cases, as well as remaining challenges. I find that EU policywas a decisive national policy driver in both cases. In Greece, feed-in-tariffs created a more secureinvestment environment and a more level playing field for producers and technologies. In Sweden, thegreen certificates served to promote RES but could not avoid market control by larger players. In bothcases, rent extraction mechanisms hindering competition were found along administrative and networkaccess barriers affecting mostly wind power. In Greece, adjustments are needed to further promote PVand better manage public funds and excess profits. Market liberalization is also necessary. In Sweden, thecertificates market expansion created a more competitive environment but some technologies still needmore support. At EU level, further harmonization of rules concerning unbundling and the setting ofbinding RES targets and infringement procedures should reduce national policy risks and contribute toreduce costs for new technologies. Plurality of markets and support schemes should be pursued in orderto create a large base of technologies while international markets for more mature technologies should beestablished. A more transparent process in achieving and revising targets at national levels should also beestablished while measures to avoid lock-ins should be pursued.
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Future business model for district heating based on renewables in Ile-de-FrancePONCET, Thomas January 2014 (has links)
District heating is an efficient way to integrate renewable energies in the energy mix. In the French region Ile-de-France, district heating and renewables have known strong developments for several years, and they are expected to grow much more in the future. The expansion of renewable energies depends partly on their competitiveness compared to fossil fuels, which is related to public subsidies, and on the spread of district heating networks in the region. Thus, it could be assess what is the future business model for district heating based on renewables in Ile-de-France. The data at the disposal of ADEME, the French agency for environment and renewable energies, show that district heating systems based on biomass could soon become more competitive than fossil fuels, whereas systems based on geothermal heat have fairly high costs. Yet, geothermal heat is more developed than biomass, and is expected to reach the targets set by the regional action plan for 2020, on the contrary to biomass. Though the increasing competitiveness of renewables will cut the necessity of public subsidies, the difficulty to reach some regional targets might mean that further actions should be implemented. From the energy operators’ point of view, the sector of district heating will surely grow considerably and therefore represent a large potential of development for those companies.
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Assessing the environmental sustainability of an apparel supply chain : the development of a conceptual model based on a comparative study of preferred tools and actual practicesBarås, Madeleine January 2015 (has links)
The apparel and textile industry is one of the largest in the world and is characterised by complex, global supply chains, water and chemical intensive processes as well as environmentally harmful raw material extraction and production. Because of this, environmental sustainability has become a key issue for the businesses in recent years. With this in mind, and considering an increasing demand for textile and apparel goods, the industry is in urgent need of improving the environmental footprint of its products. However, lack of transparency and available data throughout apparel supply chains decrease chances of producing accurate sustainability assessments, which in turn obstruct improvement measures. Moreover, companies often lack the in-house competence required to manage and create strategies for sustainability assessments. In this study an overview of an apparel supply chain is provided, highlighting phases, sub phases, input and environmental indicators. Appropriate tools for assessing the environmental sustainability of such a supply chain are inventoried and examined. Based on a case study, a literature review and a stakeholder opinion assessment, misalignments between actual practices within an apparel company and recommended practices of the researcher and stakeholder communities are uncovered. These identified misalignments enabled the development of a conceptual model, aiming at facilitating the process of developing an environmental sustainability assessment strategy within an apparel company.
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