No description available.

Solar energy is of huge interest due to the current situation with global warming. A number of solar technologies have been developed, such as photovoltaic, concentrated solar power, and solar water heating systems, to name a few. However, the technologies are being slowly implemented, and Botswana, with generous amounts of sun, is particularly suitable for solar energy. The opportunities were investigated due to the overwhelming and horrifying warnings echoed by many of the world's scientists regarding global warming. First, a handful of solar technologies were thoroughly investigated. A field study at Gakgatla village was then conducted, where the locals were interviewed. The interviews were analyzed, and solutions were suggested based on the identified needs of the locals. The biggest challenges identified were the lack of electricity in many of the households, parental figures not being supportive of the children's education, and theft. Additionally, many locals cooked with firewood. The most helpful solution but difficult to implement is photovoltaic panels. Solar water heating systems would also be helpful to the locals who predominantly had cold water. Additionally, solar cookers could help minimize exposure to hazardous smoke. Lastly, solar lamps could help students study during nighttime. Some locals also showed huge enthusiasm for what the future partnership with Botho University will bring. It is encouraged to develop a prototype of a solar cooker, particularly the parabolic solar cooker, in order to install solar cookers in Gakgatla village. Solar dryers would also greatly benefit the locals and are also suggested developments. Both of the mentioned solutions would help minimize the locals' exposure to the hazards of cooking with firewood. The solar dryers will also help eliminate bacteria by drying the food in a protected space inside a container.

The tea industry in Kenya is among the main consumers of firewood for its intensive thermal energy demand. Along with the growing concerns about firewood depletion, tea factories have begun transitioning to alternative fuels to power their boilers. Briquettes made of biomass residues are among the promising solutions; however, they are not yet widely adopted. This study was conducted to identify the factors that motivate the tea factories to use biomass briquettes instead of firewood and the factors hindering such substitution. The substitution potential was assessed, and the drivers and barriers of the substitution were examined using a combination of SWOT (strengths, weaknesses, opportunities, and threats) analysis and a PESTEL (political, economic, social, technological, environmental, and legal) framework. The findings suggest that even though using biomass briquettes is technically possible, it is not economically favorable for tea factories. The SWOT/PESTEL analysis identified 27 factors influencing the substitution. Among the key drivers are the depleting supply of firewood, the availability of biomass residues, and the external support from development organizations to improve the technical capacity in both tea and briquette industries. The study revealed the barriers to substitution include the cost competitiveness, insufficient supply, and varying quality of briquettes, as well as the lack of awareness and knowledge of briquettes.

Die vorliegende Dissertation beinhaltet eine detaillierte Analyse traditioneller und moderner Bioenergie, sowie deren möglicher Entwicklungspfade und Auswirkung auf Ernährungssicherheit im ländlichen Tansania. Die Arbeit bereichert die wissenschaftlichen Debatten mittels Aufzeigen von Optionen der nachhaltigen Produktion und Verbrauch von Bioenergie. Der Komplex wird in vier separaten und begutachteten Fachartikeln (drei publiziert, einer under review) bearbeitet. Alle Publikationen erzielen Aussagen für vier Einkommensgruppen auf lokaler Ebene. Für eine optimale Analyse ist die Arbeit thematisch in die Forschungsgebiete traditionelle und moderne Bioenergie unterteilt, die sich auch in den Kapiteln bzgl. des aktuellen Forschungsstandes sowie der Abfolge der Fachartikel widerspiegeln. Die erste Publikation beschäftigt sich mit traditionellem Bioenergiekonsum und der postulierten Einführung eines feuerholz-spezifischen, energetisch optimierten Kochers in dem Hauptuntersuchungsdorf Laela. Die Effekte einer Einführung von technologisch optimierten Holzkohlemeilern werden in der zweiten Publikation widergegeben. Nach diesem Fokus auf traditionelle Bioenergie analysiert der dritte Artikel die Effekte auf Nahrungsmittelsicherheit, die sich aus der angenommenen Verstromung von Pflanzenölen ergeben. Der vierte Artikel analysiert die Möglichkeiten einer erhöhten Palmölproduktion und leitet Ergebnisse für die tansanische Region Kigoma ab. Eine finale Empfehlung dieser Dissertation ist, dass die Verbreitung und Nutzung von verbesserten Kochern stark erhöht werden muss. Gleichzeitig sollten politischen Maßnahmen ergriffen werden, die Zugang und Verfügbarkeit von verlässlicher, erschwinglicher und nachhaltiger traditioneller wie moderner Bioenergie garantieren. Zudem muss die Etablierung einer effizienteren wie nachhaltigeren Holzkohle-Wertschöpfungskette vorangetrieben werden. Pflanzenölbasierte Elektrizitätsproduktion dagegen wirkt sich negativ auf die Ernährungssicherheit aus. / This PhD thesis provides a detailed analysis of the traditional and modern bioenergy situation as well as their development pathways and their respective influence on food security in case study villages in rural Tanzania. It adds to the current literature as it provides a profound understanding of how to enhance and sustain bioenergy production and consumption in terms of resource capacity and overall sustainability. For this, it comprises four peer-reviewed papers (3 published, one under review). All papers derive results for four income groups at local level. For an optimized analysis, the dissertation is thematically subdivided into the research areas of traditional and modern bioenergy which is displayed in the state of art research sections as well as the clustering of the papers. The first paper focuses on traditional bioenergy consumption and the potential introduction of a firewood-efficient stove in the major case-study village Laela. The effects of the introduction of more efficient kiln technology on resource consumption in the same village are mirrored in the second publication. After this focus on traditional bioenergy, the third paper investigates food security effects resulting out of the assumed use of vegetable oil for electrification purposes. The fourth paper analyses options for increased palm oil production and derives results for the Tanzanian region of Kigoma. The final recommendation of the thesis is that the prevalence and use of improved stoves needs to be increased substantially. Simultaneously, policy measures that foster the access to and availability of reliable, affordable and sustainable traditional as well as modern energy should be implemented. Furthermore, the establishment of a more efficient and sustainable charcoal value chain needs to be promoted. Vegetable oil based electrification, however, does not contribute towards food security.

Made available in DSpace on 2014-12-17T14:58:25Z (GMT). No. of bitstreams: 1 WaldecioSAN.pdf: 2259202 bytes, checksum: 5cc6fb8a72468793d81d509b30ee2013 (MD5) Previous issue date: 2007-03-02 / The present work deals with an evaluation of the environmental impacts arised from a typical ceramics industry located in the Serid? region of Rio Grande do Norte State. That region contains the largest State s producing basin of red ceramics. The district of Parelhas stands out as the largest producing nucleus. The studied company is located in the rural zone of Parelhas, it was selected as study object because it possesses a great part of the representative characteristics of the Region s ceramics park as a whole. Impacts produced at the implantation and operation phases of the Company had been evaluated, being this last phase subdivided in stages of the productive process. Among found adverse impacts, they are distinguished: losses in air quality, undesirable noises, microclimatic alterations, impoverishment of the ground, elimination of the vegetal covering, agricultural exodus, crisis in cattle agriculture and, superficial and underground water contamination, beyond risks ocupational diseases and industrial accidents. The Leopold s interactive matrix, that summarizes results of the work, was presented in form of 15 (fifteen) tables that display impacts classified in qualitative and quantitative way. Totally, 175 (one hundred and seventy-five) significant impacts produced by this Company had been identified, being 114 (one hundred and fourteen) negative, 38 (thirty-eight) positive and 23 (twenty-three) among mixed, indefinite and inert ones. In the work, before the evaluation of impacts properly said, it was constructed a diagnostic table of the ambient situation at a previous moment to implantation of the Company, elaborated on basis of inferences and historical researches. It was proposed still, mitigative steps for adverse impacts identified, as also elaborated a program to accompaniment and observing that the fulfilment of indicated mitigative steps guarantees. The final part of the work contemplates conclusions and suggestions that aim to influence positively the presented sight in terms of environmental management / O presente trabalho trata de uma avalia??o de impactos ambientais gerados por uma ind?stria cer?mica t?pica da regi?o do Serid? do Rio Grande do Norte. Essa regi?o abriga a maior bacia produtora de cer?mica vermelha do Estado, destacando-se o munic?pio de Parelhas como maior n?cleo produtor. A empresa estudada localiza-se na zona rural do munic?pio de Parelhas, foi escolhida como objeto de estudo por reunir boa parte das caracter?sticas representativas do parque cer?mico da Regi?o como um todo. Foram avaliados os impactos produzidos nas fases de implanta??o e opera??o da Empresa, sendo esta ?ltima fase subdividida em etapas do processo produtivo. Entre os impactos adversos encontrados, destacam-se: perdas na qualidade do ar, ru?dos indesej?veis, altera??es no microclima, empobrecimento do solo, elimina??o da cobertura vegetal, ?xodo rural, crise na agricultura e pecu?ria, contamina??o de ?guas superficiais e subterr?neas, al?m de riscos de doen?as profissionais e acidentes de trabalho. A matriz interativa de Leopold, que resume os resultados do trabalho, foi apresentada na forma de 15 (quinze) tabelas que exp?em os impactos classificados de modo qualitativo e quantitativo. No total, foram identificados 175 (cento e setenta e cinco) impactos significativos produzidos por essa Empresa, sendo 114 (cento e quatorze) negativos, 38 (trinta e oito) positivos e outros 23 (vinte e tr?s) entre mistos, indefinidos e neutros. No trabalho, antes da avalia??o de impactos propriamente dita, foi constru?da uma tabela de diagn?stico da situa??o ambiental num momento anterior ? implanta??o da Empresa, elaborada com base em infer?ncias e pesquisas hist?ricas. Foram propostas ainda, medidas mitigadoras para impactos adversos identificados, como tamb?m elaborado um programa de acompanhamento e monitoramento que garanta o cumprimento das medidas mitigadoras indicadas. A parte final do trabalho contempla as conclus?es e sugest?es que visem influenciar positivamente o quadro apresentado em termos de gest?o ambiental

This dissertation discusses logistical aspects of the Persians invasion of Greece; the Athenian need for timber for building warships; supply problems in their assault on Syracuse; and the march of Alexander's army from Macedonia into Asia. The amount of cereals needed by the Persian and Greek armies and navies is calculated from modern nutritional data and an estimate of the numbers of combatants. The location and size of the Persian food dumps; the excavation of the Athos canal; and the ships and materials needed to build the bridges of boats are considered. The Athenian need for ship-timber led to the costly occupation of Amphipolis. An assured supply of cereals was one motive for the disastrous Sicilian Expedition. The Athenian fleet was an inefficient long-range support for an army which had to protect its non-combatant sailors. This was realised by Alexander the Great, who crossed the Hellespont without naval support. / Classics and Modern European Languages / M.A. (Classics)

<p>Denna avhandling behandlar rökgasutsläpp av persistenta organiska föroreningar, framförallt dioxiner, vid förbränning av fasta biobränslen och torrt hushållsavfall i relativt små anläggningar (5-600 kW) utan avancerad rökgasreningsteknik.</p><p>Samförbränning av avfall och biobränsle i effektiva mindre biobränslepannor testades som en alternativ strategi till den vanligen förekommande storskaliga hanteringen och förbränningen fast hushållsavfall. Medan storskalig förbränning av avfall ger investeringsmässiga fördelar med rökgasreningsteknik etc. kan små lokala anläggningar ha transportmässiga fördelar och möjligheter till utnyttjande av lokala biobränsletillgångar. Källsorterat, torrt, brännbart hushållsavfall insamlades från hushåll i glesbygd och samförbrändes i brikettform med energigräset rörflen i 150-600 kW biobränslepannor. Endast undantagsvis understeg dioxinemissionerna gällande gränsvärden för avfallsförbränning och nivåerna av väteklorid i rökgas översteg gränsvärdena flerfaldigt. Det bedömdes att någon form av extra rökgasrening är nödvändig för att säkerställa nivågränserna. Dioxiner hittades också i det eldade avfallet, framförallt i textilfraktionen. Dioxinmängderna i rökgaserna var oftast lägre än i det ingående bränslet.</p><p>Intermittent pelletseldning gav oväntat höga utsläpp av dioxiner med en emissionsfaktor på 28 ng(WHO-TEQ)/kg. Vedeldning i en modern miljömärkt villapanna gav betydligt lägre utsläpp av dioxiner än eldning i en gammal kombipanna och eldning med full lufttillförsel, som kan jämföras med användning av ackumulatortank, resulterade i upp till 90% minskning av utsläpp av dioxiner jämfört med eldning med reducerat lufttillskott (’pyreldning’). Eldning av plastavfall i en vedpanna gav höga utsläpp av dioxiner.</p><p>Okontrollerad förbränning av trädgårdsavfall och hushålls avfall i tunna eller som öppen eld ’bakgårdsbränning’, gav stora variationer i utsläppsnivåer som bara delvis kunde kopplas till avfallsinnehåll. Resultaten visar att denna typ av förbränning kan vara en betydande källa till dioxiner i miljön, och ett emissionsfaktorintervall på 4-72 ng (WHO-TEQ)/kg föreslås för bedömningar av utsläpp från backgårdsbränning av avfall med låga eller måttliga klorhalter.</p><p>En sammanfattande slutsats av alla försök är att dioxin utsläpp beror på komplicerade samband mellan bränsleinnehåll och förbränningsbetingelser. Bränslen med mycket höga klorhalter av ger oftast högre utsläpp av dioxiner än bränslen med låga klorhalter medan små skillnader döljs av variationer i förbränningsbetingelser.</p> / <p>This thesis deals with emissions of persistent organic pollutants, primarily dioxins, from the combustion of solid biofuels and dry combustible household waste in relatively small facilities, 5-600 kW, without advanced air pollution controls.</p><p>Co-combustion of waste and biofuel in effective small boilers was tested as an alternative to prevailing large-scale management and combustion strategies for handling municipal solid waste. This approach includes no advanced air pollution control systems, but offers two advantages: limiting transport and providing scope to use local biofuel resources. Source-sorted, dry, combustible household waste was collected from households in a sparsely populated area and co-combusted as briquettes together with reed canary-grass in 150-600 kW biofuel boilers. Most trials showed difficulties to meet regulative limits for the emissions of dioxins valid for incineration of MSW and the regulated limits for emissions of hydrochloric acid were exceeded manifold. It was concluded that additional flue-gas cleaning will be needed to ensure that emissions are sufficiently low. Dioxins were also found in the waste, especially in the textile fraction. The mass of dioxins in the flue-gas emissions was generally lower than the mass in the fuel input.</p><p>Intermittent combustion of wood pellets in a residential boiler resulted in an unexpectedly high dioxin emissions factor of 28 ng (WHO-TEQ)/kg fuel. Combustion of wood in a modern environmentally certified boiler yielded considerably lower dioxin emissions than combustion in an old boiler, and combustion with a full air supply, i.e. with use of heat storage tank, resulted in up to 90% reductions in dioxin emission factors compared to combustion with reduced air supply. Combustion of plastic waste in a residential wood boiler resulted in high emissions of dioxins.</p><p>Tests of uncontrolled combustion of garden and household waste in barrels or open fires, ‘backyard burnings’, resulted in emissions with large variations that could only be partly correlated to the waste constituents. The results imply that this may be an important source of dioxins in the environment and an emission factor range of 4-72 ng (WHO-TEQ)/kg is suggested for estimating emissions from backyard burnings of lightly and moderately chlorine-contaminated waste.</p><p>A summarized conclusion from all of the experiments is that predicting emission levels from waste contents is not straightforward (except that fuels with very high chlorine levels will usually result in high levels of dioxins in flue-gas emissions). Moderate differences in chlorine levels will usually be masked by the effect of variations in combustion conditions.</p>

This dissertation discusses logistical aspects of the Persians invasion of Greece; the Athenian need for timber for building warships; supply problems in their assault on Syracuse; and the march of Alexander's army from Macedonia into Asia. The amount of cereals needed by the Persian and Greek armies and navies is calculated from modern nutritional data and an estimate of the numbers of combatants. The location and size of the Persian food dumps; the excavation of the Athos canal; and the ships and materials needed to build the bridges of boats are considered. The Athenian need for ship-timber led to the costly occupation of Amphipolis. An assured supply of cereals was one motive for the disastrous Sicilian Expedition. The Athenian fleet was an inefficient long-range support for an army which had to protect its non-combatant sailors. This was realised by Alexander the Great, who crossed the Hellespont without naval support. / Classics and Modern European Languages / M.A. (Classics)

Denna avhandling behandlar rökgasutsläpp av persistenta organiska föroreningar, framförallt dioxiner, vid förbränning av fasta biobränslen och torrt hushållsavfall i relativt små anläggningar (5-600 kW) utan avancerad rökgasreningsteknik. Samförbränning av avfall och biobränsle i effektiva mindre biobränslepannor testades som en alternativ strategi till den vanligen förekommande storskaliga hanteringen och förbränningen fast hushållsavfall. Medan storskalig förbränning av avfall ger investeringsmässiga fördelar med rökgasreningsteknik etc. kan små lokala anläggningar ha transportmässiga fördelar och möjligheter till utnyttjande av lokala biobränsletillgångar. Källsorterat, torrt, brännbart hushållsavfall insamlades från hushåll i glesbygd och samförbrändes i brikettform med energigräset rörflen i 150-600 kW biobränslepannor. Endast undantagsvis understeg dioxinemissionerna gällande gränsvärden för avfallsförbränning och nivåerna av väteklorid i rökgas översteg gränsvärdena flerfaldigt. Det bedömdes att någon form av extra rökgasrening är nödvändig för att säkerställa nivågränserna. Dioxiner hittades också i det eldade avfallet, framförallt i textilfraktionen. Dioxinmängderna i rökgaserna var oftast lägre än i det ingående bränslet. Intermittent pelletseldning gav oväntat höga utsläpp av dioxiner med en emissionsfaktor på 28 ng(WHO-TEQ)/kg. Vedeldning i en modern miljömärkt villapanna gav betydligt lägre utsläpp av dioxiner än eldning i en gammal kombipanna och eldning med full lufttillförsel, som kan jämföras med användning av ackumulatortank, resulterade i upp till 90% minskning av utsläpp av dioxiner jämfört med eldning med reducerat lufttillskott (’pyreldning’). Eldning av plastavfall i en vedpanna gav höga utsläpp av dioxiner. Okontrollerad förbränning av trädgårdsavfall och hushålls avfall i tunna eller som öppen eld ’bakgårdsbränning’, gav stora variationer i utsläppsnivåer som bara delvis kunde kopplas till avfallsinnehåll. Resultaten visar att denna typ av förbränning kan vara en betydande källa till dioxiner i miljön, och ett emissionsfaktorintervall på 4-72 ng (WHO-TEQ)/kg föreslås för bedömningar av utsläpp från backgårdsbränning av avfall med låga eller måttliga klorhalter. En sammanfattande slutsats av alla försök är att dioxin utsläpp beror på komplicerade samband mellan bränsleinnehåll och förbränningsbetingelser. Bränslen med mycket höga klorhalter av ger oftast högre utsläpp av dioxiner än bränslen med låga klorhalter medan små skillnader döljs av variationer i förbränningsbetingelser. / This thesis deals with emissions of persistent organic pollutants, primarily dioxins, from the combustion of solid biofuels and dry combustible household waste in relatively small facilities, 5-600 kW, without advanced air pollution controls. Co-combustion of waste and biofuel in effective small boilers was tested as an alternative to prevailing large-scale management and combustion strategies for handling municipal solid waste. This approach includes no advanced air pollution control systems, but offers two advantages: limiting transport and providing scope to use local biofuel resources. Source-sorted, dry, combustible household waste was collected from households in a sparsely populated area and co-combusted as briquettes together with reed canary-grass in 150-600 kW biofuel boilers. Most trials showed difficulties to meet regulative limits for the emissions of dioxins valid for incineration of MSW and the regulated limits for emissions of hydrochloric acid were exceeded manifold. It was concluded that additional flue-gas cleaning will be needed to ensure that emissions are sufficiently low. Dioxins were also found in the waste, especially in the textile fraction. The mass of dioxins in the flue-gas emissions was generally lower than the mass in the fuel input. Intermittent combustion of wood pellets in a residential boiler resulted in an unexpectedly high dioxin emissions factor of 28 ng (WHO-TEQ)/kg fuel. Combustion of wood in a modern environmentally certified boiler yielded considerably lower dioxin emissions than combustion in an old boiler, and combustion with a full air supply, i.e. with use of heat storage tank, resulted in up to 90% reductions in dioxin emission factors compared to combustion with reduced air supply. Combustion of plastic waste in a residential wood boiler resulted in high emissions of dioxins. Tests of uncontrolled combustion of garden and household waste in barrels or open fires, ‘backyard burnings’, resulted in emissions with large variations that could only be partly correlated to the waste constituents. The results imply that this may be an important source of dioxins in the environment and an emission factor range of 4-72 ng (WHO-TEQ)/kg is suggested for estimating emissions from backyard burnings of lightly and moderately chlorine-contaminated waste. A summarized conclusion from all of the experiments is that predicting emission levels from waste contents is not straightforward (except that fuels with very high chlorine levels will usually result in high levels of dioxins in flue-gas emissions). Moderate differences in chlorine levels will usually be masked by the effect of variations in combustion conditions.

The aim of this project is heating and warm water preparation for apartment block in Choceň (Pardubice region). Apartment block has three aboveground heated floors and one underground unheated floor. The heat source is gasifying firewood boiler or pellet boiler which is at the same time used for water heating but only in the winter time. The other parts of the year the solar collectors are installed and used for water heating. The heat source is located in detached room with its own access, in boiler room.