No description available.

published_or_final_version / Urban Planning and Environmental Management / Doctoral / Doctor of Philosophy

Access to electricity might in some parts of the world seem evident. However, Ethiopia struggles to provide its large and growing population with electricity. Although around all the households in the capital Addis Ababa are connected to the electricity grid, the grid is unreliable and results in daily outages. As the photovoltaic (PV) potential in Addis Ababa on the other hand is great, this thesis examines the feasibility and profitability of decentralized PV adoption with battery and hydrogen storage respectively. Based on an ongoing construction project in the sub-city Yeka, Addis Ababa, a reference building was used to simulate the PV systems with battery and hydrogen storage. Furthermore, a load profile based on time-use diaries was developed and used in the simulations, as data on household electric consumption was non-existent. The load profile resulted in an average daily use of 1341 kWh and a 165 kW peak for all of the 130 apartments in the reference building. The results of the simulations indicated that neither of the two systems were feasible nor profitable to implement on the reference building. The PV-system with battery storage was cheaper and required less installed PV capacity, however the cost of energy for both systems was significantly higher than the current cost of energy in Ethiopia. The installed PV capacity of both systems exceeded the maximum capacity that was feasible on the reference building.

Grid-connected photovoltaic (PV) capacity is increasing worldwide, mainly due to extensive subsidy schemes for renewable electricity generation. A majority of newly installed systems are distributed small-scale systems located in distribution grids, often at residential customers. Recent developments suggest that such distributed PV generation (PV-DG) could gain more interest in Sweden in the near future. With prospects of decreasing system prices, an extensive integration does not seem impossible. In this PhD thesis the opportunities for utilisation of on-site PV generation and the consequences of a widespread introduction are studied. The specific aims are to improve modelling of residential electricity demand to provide a basis for simulations, to study load matching and grid interaction of on-site PV and to add to the understanding of power system impacts. Time-use data (TUD) provided a realistic basis for residential load modelling. Both a deterministic and a stochastic approach for generating different types of end-use profiles were developed. The models are capable of realistically reproducing important electric load properties such as diurnal and seasonal variations, short time-scale fluctuations and random load coincidence. The load matching capability of residential on-site PV was found to be low by default but possible to improve to some extent by different measures. Net metering reduces the economic effects of the mismatch and has a decisive impact on the production value and on the system sizes that are reasonable to install for a small-scale producer. Impacts of large-scale PV-DG on low-voltage (LV) grids and on the national power system were studied. Power flow studies showed that voltage rise in LV grids is not a limiting factor for integration of PV-DG. Variability and correlations with large-scale wind power were determined using a scenario for large-scale building-mounted PV. Profound impacts on the power system were found only for the most extreme scenarios. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 711

Accurate and current land use information for urban areas is important for effective management and planning. Over the years, researchers/planners have relied heavily on aerial photographs for land use information of urban areas because of the limitations of deriving more accurate land use estimates from satellite remote sensing data. The main problem involved in producing accurate land use maps of cities and towns from satellite images is that urban areas consist of a complex assemblage of different land cover types, many of which have very similar spectral reflectance characteristics. This is because land use is an abstract concept- n amalgam of economic, social and cultural factors-that is defined in terms of functions rather than forms. The relationship between land use and the multispectral signals detected by a satellite sensor is therefore both complex and indirect. In many European cities, residential areas are characterized by a complex spatial assemblage of tile roof, slate roof, glass roof buildings, as well as tarmac, concrete and pitch roads, and gardens (comprised of grass lawns, trees and plants). In North American cities, roofing materials are more commonly composed of wood and shingles. In both settings all these "objects" together form the residential areas or residential districts of town or city, but each of them has a different spectral reflectance. So, in generating a land use map from remotely sensed image, buildings, roads, gardens, open spaces will be identified separately. Keeping this in mind, this thesis evaluates eight selected land use classification methods for the Vancouver metropolitan area, identifies the most accurate and suitable method for urban land use classification, and produces a land use map of the study area based on the most suitable method. The study area is a part of Greater Vancouver Regional District (GVRD). It includes Vancouver, Burnaby, Richmond, Delta, and parts of seven other municipalities. The whole area is highly urbanized and commercialized. Agricultural lands are present in the southern part of the study area (which includes parts of Richmond, Delta and Surrey). For this study four sources of data have been used. The 1996 Greater Vancouver regional District (GVRD) land use map is the basic source of land use information. A remotely sensed image of May 1999 (Landsat 7) has been used for the identification of land cover data, Vancouver and Fraser valley orthophotos (May/July 1995) have been used to locate sample sites, and aerial photos of May 1999 (1:30,000) have been used for ground verification.

Orientador: Jansle Vieira Rocha / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-25T12:57:44Z (GMT). No. of bitstreams: 1 Manabe_VictorDanilo_M.pdf: 5304321 bytes, checksum: 80a3f7d1cb298d39ab607a7a6015ab38 (MD5) Previous issue date: 2014 / Resumo: O aumento na produção da cana-de-açúcar vem gerando grande discussão sobre a sustentabilidade da produção e a sua influência direta na mudança de uso da terra, principalmente em áreas de pastagem e cultura anual. O estudo da dinâmica da cana-de-açúcar tem influência direta em questões como a composição da produção agrícola, nos impactos sobre a biodiversidade, no desenvolvimento social e humano e na definição de políticas públicas. Índice de vegetação, através de séries temporais de imagens, tem sido utilizado para mapeamento de uso da terra de grandes áreas (estados, países ou regiões), através de produtos do sensor MODerate resolution Imaging Spectroradiometer (MODIS). Este trabalho avaliou o desempenho de diferentes técnicas de filtragem em séries temporais e também realizou detecção automatizada de áreas de cana-de-açúcar e principais usos da terra para os anos de 2005, 2008 e 2012, e consequente mudança de uso da terra, utilizando séries temporais NDVI/MODIS, no estado de Mato Grosso. Foi utilizado o NDVI dos produtos MOD13Q1 e MYD13Q1 do sensor MODIS para identificação das áreas de diferentes usos da terra. Primeiramente foram avaliados os filtros Savitz-Golay , HANTS e Flat Bottom de maneira individual e também com a combinação Flat Bottom + HANTS e Flat Bottom + Savitz-Golay, nas séries de dados somente referentes ao NDVI MODIS/Terra e em conjunto com NDVI MODIS/Aqua. Tendo o resultado, que a utilização MODIS/Terra e MODIS/Aqua trouxe melhora significativa no resultado da classificação, quando utilizado em conjunto a algum filtro de série temporal, sendo o Savitzky-Golay, o que apresentou melhor resultado na diferenciação dos alvos. Na identificação e mapeamento automatizado, de áreas de cana-de-açúcar e outros principais usos da terra para a região (cultura anual, pastagem, cerrado e mata), para os anos de 2005, 2008 e 2012, os valores de acertos para cana-de-açúcar foram de 83%, 82% e 85% nos anos 2005, 2008 e 2012, respectivamente, e o acerto total foram de 89%, 88% e 89%, também para os anos 2005, 2008 e 2012. Ao cruzar os mapeamentos, foi possível realizar a análise da mudança de uso da terra para cana-de-açúcar. A certeza na mudança de uso da terra, quando implementa em áreas anteriormente destinadas a agricultura anual foi de 80% e 82%, na comparação de 2005 para 2008 e 2008 para 2012, respectivamente. No uso anterior de pastagem e cerrado este valor apresentou valores de 69% e 30%, respectivamente, na mudança de 2005 para 2008, e 66% e 34%, respectivamente, na mudança de 2008 para 2012. O resultado na analise de mudança de usa da terra teve a predominância de áreas de pastagem como principal uso anterior a cana-de-açúcar, seguida pela agricultura e o cerrado como responsável pelo restante do uso anterior da terra. Assim, o método para identificação da mudança de uso da terra apresentou um erro a ser considero, porém a tendência de ocorrência se apresenta de maneira consistente / Abstract: The production increase of sugarcane has generated discussion about the sustainability of production and its direct impact on the land use change, especially in pasture and annual crops areas. The study of the dynamics of sugarcane has a direct impact on issues such as the composition of agricultural production, the impacts on biodiversity, social and human development and the definition of public policies. Vegetation index through time series images have been used to map land use of large areas (states, countries or regions) using sensor Moderate Resolution Imaging Spectroradiometer (MODIS). This study evaluated the performance of different time series smoothing techniques and also held automated detection of sugarcane areas and main land uses for the years 2005, 2008 and 2012, and the consequent land use change, using NDVI/MODIS time series in Mato Grosso state. It was used NDVI product of MOD13Q1 and MYD13Q1 to identify areas of different land uses. At first, Savitz-Golay, Hants and Flat Bottom individually and also the combination Flat Bottom + Hants and Flat Bottom + Savitz-Golay, it was applied on NDVI time series data only related to MODIS/Terra and in conjunction with MODIS/Aqua. The result was that the use MODIS/Terra and MODIS/Aqua brought significant improvement in the overall classification, when used in conjunction with any time series smoothing, and the Savitzky-Golay showed better results in the differentiation of targets. The mapping areas of sugarcane and other major land uses (annual crops, grassland, savanna and forest), for the years 2005, 2008 and 2012, the number of right answers for sugarcane were 83 %, 82 % and 85 % in the years 2005, 2008 and 2012, respectively, and total accuracy were 89 %, 88 % and 89 %, also for the years 2005, 2008 and 2012. When crossing the maps, it was possible to perform the analysis of the land use change to cane sugar. The certainty of change in land use, when deploy in areas previously designed to annual agriculture was 80 % and 82 % in 2005 compared to 2008 and 2008 compared to 2012 respectively. The past use of grassland and savannah, this value, showed values of 69 % and 30 %, respectively, in the change from 2005 to 2008, and 66 % and 34 %, respectively, in the change from 2008 to 2012. The result of the study of land use changing had the predominance of grazing areas as the former principal use sugarcane, followed by agriculture and savanna as responsible for the remainder of the previous land use. Thus, the method to identifying the change of land use has an error to consider, but the trend appears to occur consistently / Mestrado / Planejamento e Desenvolvimento Rural Sustentável / Mestre em Engenharia Agrícola

Accurate and current land use information for urban areas is important for effective management and planning. Over the years, researchers/planners have relied heavily on aerial photographs for land use information of urban areas because of the limitations of deriving more accurate land use estimates from satellite remote sensing data. The main problem involved in producing accurate land use maps of cities and towns from satellite images is that urban areas consist of a complex assemblage of different land cover types, many of which have very similar spectral reflectance characteristics. This is because land use is an abstract concept- n amalgam of economic, social and cultural factors-that is defined in terms of functions rather than forms. The relationship between land use and the multispectral signals detected by a satellite sensor is therefore both complex and indirect. In many European cities, residential areas are characterized by a complex spatial assemblage of tile roof, slate roof, glass roof buildings, as well as tarmac, concrete and pitch roads, and gardens (comprised of grass lawns, trees and plants). In North American cities, roofing materials are more commonly composed of wood and shingles. In both settings all these "objects" together form the residential areas or residential districts of town or city, but each of them has a different spectral reflectance. So, in generating a land use map from remotely sensed image, buildings, roads, gardens, open spaces will be identified separately. Keeping this in mind, this thesis evaluates eight selected land use classification methods for the Vancouver metropolitan area, identifies the most accurate and suitable method for urban land use classification, and produces a land use map of the study area based on the most suitable method. The study area is a part of Greater Vancouver Regional District (GVRD). It includes Vancouver, Burnaby, Richmond, Delta, and parts of seven other municipalities. The whole area is highly urbanized and commercialized. Agricultural lands are present in the southern part of the study area (which includes parts of Richmond, Delta and Surrey). For this study four sources of data have been used. The 1996 Greater Vancouver regional District (GVRD) land use map is the basic source of land use information. A remotely sensed image of May 1999 (Landsat 7) has been used for the identification of land cover data, Vancouver and Fraser valley orthophotos (May/July 1995) have been used to locate sample sites, and aerial photos of May 1999 (1:30,000) have been used for ground verification. / Arts, Faculty of / Geography, Department of / Graduate

<p>In the context of climate change, increasing demands for freshwater make it necessary to manage our water resources in a sustainable way and find innovative ways to extend their life. An integrated water management approach needs to consider anthropogenic water use and reuse which represent major components of the current water cycle. In particular, unplanned, or de facto, indirect water reuse occurs in most of the U.S. river systems; however, there is little real-time documentation of it. Despite the fact that there are national and state agencies that systematically collect data on water withdrawals and wastewater discharges, their databases are organized and managed in a way that limits the ability to combine reported water data to perform large scale analysis about water use and indirect reuse. To better document these issues and to demonstrate the utility of such an analysis, I studied the Wabash River Watershed located in the U.S. Midwest. Existing data for freshwater extraction, use, discharge, and river streamflow were collected, curated and reorganized in order to characterize the water use and reuse within the basin. Indirect water reuse was estimated by comparing treated wastewater discharges with stream flows at selected points within the watershed. Results show that during the low flow months of July-October 2007, wastewater discharges into the Wabash River basin contributed 82 to 121% of the stream flow, demonstrating that the level of water use and unplanned reuse is significant. These results suggest that intentional water reuse for consumptive purposes such as landscape or agricultural irrigation could have substantial ecological impacts by diminishing stream flow during vulnerable low flow periods. This research also completed a time series watershed-scale analysis of water use and unplanned indirect reuse for the Wabash River Watershed from 2009 to 2017. Results document the occurrence of indirect water reuse over time, ranging from 3% to 134% in a water-rich area of the U.S. The time series analysis shows that reported data effectively describe the water use trends through nine years, clearly reflecting both anthropogenic and natural events in the watershed, such as the retirement of thermoelectric power plants, and the occurrence of an extreme drought in 2012. Results demonstrate the feasibility and significance of using available water datasets to perform large scale water use analysis, describe limitations encountered in the process, and highlight areas for improvement in water data management.</p>