This research investigates ways to reduce the carbon dioxide emissions from the cement industry. Cement is one of the largest sources of man-made greenhouse gases, contributing ~5% of the global total. 40% of emissions from cement come from the fuel used in the process, while the electricity used contributes a further 5%. The focus of the research is to find operational changes that can reduce emissions without the need for large capital investment. Three cement plants in the UK were investigated using four different mathematical models based on real data from the plants. A new metric for assessing the environmental impact of the fuel mix of a plant was proposed, and evidence indicates that it may be a better predictor of environmental performance than the metrics currently used in industry. The research found that consistently improving this fuel metric to best-observed levels, as well as reducing the excess air ratio to industry-standard levels had the potential to reduce fuel consumption by up to 7%, and fuel derived CO2 emissions by up to 12%. Increasing use of biomass to best-observed levels had the potential to reduce the net fuel derived CO2 emissions by up to 20%. Comparing the proposed improvements to the historic range of plant performance showed that this level of performance is within the normal operating range of the plants. A reduction of 2-4% in electricity costs and electricity derived emissions was also possible from operational changes. These savings would reduce operating costs as well as emissions, and require little to no capital investment, meaning they could be implemented directly. If successfully implemented in the near future the total savings by 2050 would be on a similar scale to those expected from much more expensive technology changes, such as upgrading to new cement plants, or installing carbon capture and storage technology.

A produção de cimento gera um impacto ambiental negativo, principalmente relacionado à emissão de dióxido de carbono (CO2). O clínquer do cimento sulfoaluminato de cálcio belítico (CSAB) possui um menor teor de óxido de cálcio e é produzido com uma reduzida temperatura de sinterização (aproximadamente 200ºC a menos em relação ao clínquer Portland), sendo considerado mais eco-amigável. Para a produção do cimento CSAB são necessárias matérias-primas ricas em alumínio e convencionalmente a bauxita é o minério utilizado para compor a farinha, o que mais onera a produção desse tipo de cimento. Soma-se ainda o fato que a geração de resíduos e subprodutos industriais torna-se inerente aos processos e o coprocessamento de resíduos vem sendo cada vez mais utilizado por razões ambientais e energéticas. Logo, fontes alternativas de alumina são fundamentais para a viabilização deste cimento e o aproveitamento de resíduos agregaria um valor econômico e sustentável ao produto final. De modo estequiométrico, a bauxita pode ser completamente substituída pelo lodo de anodização do alumínio (LAA), o qual também pode complementar o conteúdo de alumínio de outros resíduos, valorizando-os. O objetivo deste estudo foi avaliar a produção e as propriedades de clínqueres/cimentos CSAB a partir da substituição da bauxita por cinza pesada e LAA. Para a caracterização das matérias-primas, clínqueres e cimentos nos estados anidro e hidratado foram utilizadas as seguintes técnicas: fluorescência de raios X; microscopia eletrônica de varredura e espectrometria por energia dispersiva; termogravimentria; calorimetria; e difração de raios X com refinamento pelo método de Rietveld. A partir dos resultados obtidos, a substituição da bauxita foi limitada a nível parcial devido à elevada formação de belita e periclásio. Nos clínqueres produzidos, foi constatado que a presença da cinza pesada favorece a formação da estrutura cristalina ortorrômbica da fase ye’elimita. A presença dos resíduos altera a quantificação das fases, porém não compromete a estabilização das mesmas. A presença dos resíduos na composição dos cimentos afeta o período inicial de hidratação devido à redução do conteúdo de ye’elimita. Nos clínqueres produzidos com cinza pesada, ocorre a formação de até 12,6% da fase alita a 1250ºC, principal constituinte do clínquer Portland. / Cement production generates high negative environmental impact, mainly associated to CO2 emissions. Calcium sulfoaluminate belite cement clinker (CSAB) has lower content of calcium oxide, and sintering reduced temperature (about 200°C lower than that used for Portland clinker), being considered as eco-friendly binder. For its production high amount of alumina is required, however the scarcity and high cost of bauxite make these cements costly. Additionally, the generation of waste and by-products becomes a drawback in the industrial processes and the coprocessing of wastes in cement plants is increasing for environmental and energy savings reasons. Alternative sources of alumina would add an economic and sustainable value to the final product and previous work has shown that the aluminum anodizing sludge can replace bauxite in the production process. Other sources of wastes can also be a possibility to increase the production and reduce the raw materials costs of these cements. Thus, the objective of this study was the evaluation of novel CSAB cements produced with bauxite replacement by bottom ash and aluminum anodizing sludge. CSAB cements were produced in the laboratory from different amounts of sludge and ashes. The raw materials, clinkers/cements and hydration products were physicaly-chemicaly and mechanical characterized. Results showed that the mineralogy composition of CSAB clinker was strongly affected due to the addition of bottom ash. The amount of bottom ash waste replacing bauxite controls the belite and periclase formation. Also it influences the early age hydration due the reduced ye’elimite formation and important changes in the crystalline structures of this phase occurs in the clinkers. Clinkers prepared from these replacement, are able to form 12.6% of alite (main phase Portland clinker), not normally found in CSAB clinkers, being sintered at 1250°C.

O aumento da concentração de gases de efeito estufa na atmosfera levou a uma preocupação de como se reduzir as emissões destes gases. Desta preocupação surgiram instrumentos de regulação a fim de reduzir ou controlar os níveis de poluição. Dentro deste contexto, esta pesquisa analisou o setor de transportes de cargas, com ênfase no transporte de soja. No Brasil, o setor de transportes é um dos principais responsáveis pelas emissões de gases de efeito estufa provenientes da queima de combustíveis fósseis. No setor de transportes, as emissões diferem entre os modais, sendo que as ferrovias e hidrovias poluem menos que as rodovias. Desta forma, simulou-se por meio de um modelo de programação linear se a adoção de medidas regulatórias sobre as emissões de CO2 traria uma alteração no uso das ferrovias e hidrovias. Uma das constatações, ao se utilizar o modelo de Minimização de Fluxo de Custo Mínimo para o transporte de soja em 2013, foi que a capacidade de embarque nos terminais ferroviários e hidroviários desempenha um papel fundamental na redução das emissões de CO2. Se não houver capacidade suficiente, a adoção de uma taxa pode não provocar a redução das emissões. No caso do sistema de compra e crédito de carbono, seria necessária a compra de créditos de carbono, numa situação em que a capacidade de embarque nos terminais intermodais seja limitada. Verificou-se, ainda, que melhorias na infraestrutura podem desempenhar um papel mitigador das emissões. Um aumento da capacidade dos terminais ferroviários e hidroviários existentes, bem como o aumento da capacidade dos portos, pode provocar a redução das emissões de CO2. Se os projetos de expansão das ferrovias e hidrovias desenvolvidos por órgãos governamentais saírem do papel, pode-se chegar a uma redução de pouco mais de 50% das emissões de CO2. Consideraram-se ainda quais seriam os efeitos do aumento do uso de biodiesel como combustível e percebeu-se que seria possível obter reduções tanto das emissões quanto do custo de transporte. Efeitos semelhantes foram encontrados quando se simulou um aumento da eficiência energética. Por fim, percebeu-se nesta pesquisa que a adoção de uma taxa não traria tantos benefícios, econômicos e ambientais, quanto a melhoria da infraestrutura logística do país. / The increased concentration of greenhouse gases in the atmosphere has led to a concern of how to reduce emissions of these gases. From this concern, regulatory instruments were conceived in order to reduce or control pollution levels. Within this context, this research examined the freight transport sector, with emphasis on the soybean transport. In Brazil, the transportation sector is a major contributor to the greenhouse gas emissions from burning fossil fuels. In the transportation sector, emissions differ among transportation modes, with the railways and waterways polluting less than the highways. Thus, it is simulated by means of a linear programming model if the adoption of regulatory measures on CO2 emissions would bring a change in the use of railways and waterways. One of the findings, using the model of Minimum Cost Flow Minimization for soybean transport in 2013, was that the loading capacity on rail and waterway terminals plays a key role in reducing CO2 emissions. If there is an insufficient capacity, the adoption of a tax may not cause the reduction of emissions. In the case of the cap and trade system, this would require the purchase of carbon credits in a situation where the loading capacity in intermodal terminals is limited. It was found further that improvements in the infrastructure could play a mitigating role for emissions. An increase in capacity of existing rail and waterway terminals, as well as increasing the capacity of ports, can cause the reduction of CO2 emissions. If the expansion projects of railways and waterways developed by government agencies leave the paperwork, it can be reached a reduction of over 50% of CO2 emissions. It was still considered what would be the effects of increased use of biodiesel as fuel, being realized that it would be possible to obtain reductions in both emissions and the shipping cost. Similar effects were found when it was simulated an increase of energy efficiency. Finally, it was noted in this study that the adoption of a tax would not bring so many benefits, including the economic and environmental ones, to improve the country\'s logistics infrastructure.

A produção de cimento gera um impacto ambiental negativo, principalmente relacionado à emissão de dióxido de carbono (CO2). O clínquer do cimento sulfoaluminato de cálcio belítico (CSAB) possui um menor teor de óxido de cálcio e é produzido com uma reduzida temperatura de sinterização (aproximadamente 200ºC a menos em relação ao clínquer Portland), sendo considerado mais eco-amigável. Para a produção do cimento CSAB são necessárias matérias-primas ricas em alumínio e convencionalmente a bauxita é o minério utilizado para compor a farinha, o que mais onera a produção desse tipo de cimento. Soma-se ainda o fato que a geração de resíduos e subprodutos industriais torna-se inerente aos processos e o coprocessamento de resíduos vem sendo cada vez mais utilizado por razões ambientais e energéticas. Logo, fontes alternativas de alumina são fundamentais para a viabilização deste cimento e o aproveitamento de resíduos agregaria um valor econômico e sustentável ao produto final. De modo estequiométrico, a bauxita pode ser completamente substituída pelo lodo de anodização do alumínio (LAA), o qual também pode complementar o conteúdo de alumínio de outros resíduos, valorizando-os. O objetivo deste estudo foi avaliar a produção e as propriedades de clínqueres/cimentos CSAB a partir da substituição da bauxita por cinza pesada e LAA. Para a caracterização das matérias-primas, clínqueres e cimentos nos estados anidro e hidratado foram utilizadas as seguintes técnicas: fluorescência de raios X; microscopia eletrônica de varredura e espectrometria por energia dispersiva; termogravimentria; calorimetria; e difração de raios X com refinamento pelo método de Rietveld. A partir dos resultados obtidos, a substituição da bauxita foi limitada a nível parcial devido à elevada formação de belita e periclásio. Nos clínqueres produzidos, foi constatado que a presença da cinza pesada favorece a formação da estrutura cristalina ortorrômbica da fase ye’elimita. A presença dos resíduos altera a quantificação das fases, porém não compromete a estabilização das mesmas. A presença dos resíduos na composição dos cimentos afeta o período inicial de hidratação devido à redução do conteúdo de ye’elimita. Nos clínqueres produzidos com cinza pesada, ocorre a formação de até 12,6% da fase alita a 1250ºC, principal constituinte do clínquer Portland. / Cement production generates high negative environmental impact, mainly associated to CO2 emissions. Calcium sulfoaluminate belite cement clinker (CSAB) has lower content of calcium oxide, and sintering reduced temperature (about 200°C lower than that used for Portland clinker), being considered as eco-friendly binder. For its production high amount of alumina is required, however the scarcity and high cost of bauxite make these cements costly. Additionally, the generation of waste and by-products becomes a drawback in the industrial processes and the coprocessing of wastes in cement plants is increasing for environmental and energy savings reasons. Alternative sources of alumina would add an economic and sustainable value to the final product and previous work has shown that the aluminum anodizing sludge can replace bauxite in the production process. Other sources of wastes can also be a possibility to increase the production and reduce the raw materials costs of these cements. Thus, the objective of this study was the evaluation of novel CSAB cements produced with bauxite replacement by bottom ash and aluminum anodizing sludge. CSAB cements were produced in the laboratory from different amounts of sludge and ashes. The raw materials, clinkers/cements and hydration products were physicaly-chemicaly and mechanical characterized. Results showed that the mineralogy composition of CSAB clinker was strongly affected due to the addition of bottom ash. The amount of bottom ash waste replacing bauxite controls the belite and periclase formation. Also it influences the early age hydration due the reduced ye’elimite formation and important changes in the crystalline structures of this phase occurs in the clinkers. Clinkers prepared from these replacement, are able to form 12.6% of alite (main phase Portland clinker), not normally found in CSAB clinkers, being sintered at 1250°C.

O paradigma atual do uso da energia no setor industrial brasileiro é fruto da conjuntura histórica do setor energético no país e permite explicar algumas de suas características particulares, a utilização intensiva de eletricidade em processos térmicos, a eletrotermia, algo que perdura até hoje. O cenário nacional de produção de gás natural é promissor, no contexto do Pré-Sal, o que sinaliza uma oportunidade para aplicar esse recurso natural para usos energéticos com maior valor agregado, como por exemplo como energia final para a indústria. É neste contexto que se insere esta dissertação onde foi desenvolvida e aplicada uma técnica de análise de dados com objetivo de avaliar a inserção do gás natural no setor industrial brasileiro e seus impactos. A técnica de análise de dados desenvolvida constitui-se na avaliação de quatro indicadores: Demanda Adicional (DA); Impacto em Energia Primária (IEP); Impacto em Emissões de Carbono (IEC) e Impacto em Custo Energético (ICE). Nos resultados obtidos, o Setor de Metais Não-Ferrosos teve maior destaque ao apresentar a maior demanda adicional por gás natural e as maiores reduções em demanda de energia primária, emissões de CO2 e custo energético. Outros setores que se destacaram foram o Setor de Ferro e Aço e Setor de Alimentos e Bebidas. Tomando 2013 como ano-base, a demanda adicional por gás natural resultante da substituição de óleo combustível e eletricidade em processos térmicos representaria um aumento entre 37% a 42% na demanda de gás natural no setor industrial brasileiro, equivalente a 12% a 14% da oferta interna de gás natural no Brasil, ou ainda 35% a 40% da capacidade máxima do Gasbol. O impacto em energia primária representaria uma redução de 1% a 2% da demanda de energia primária do setor industrial brasileiro. O impacto em emissões de CO2 representaria uma redução de 4% a 5% das emissões de CO2 associadas ao uso de energia do setor industrial brasileiro. O impacto em custo energético representaria uma redução de 2% a 4% dos custos energéticos associados a eletricidade e óleo combustível do setor industrial brasileiro. Assim, considera-se que existe uma oportunidade de inserção do gás natural no setor industrial brasileiro resultante da substituição de óleo combustível e eletricidade por gás natural em processos térmicos. De forma geral, seus impactos reduzem a demanda de energia primária, as emissões de CO2 e o custo energético. Entretanto, trata-se de uma iniciativa de economia de energia via substituição energética, desse modo, ressalta-se necessidade de se fomentar a eficiência energética, para todos os usos finais e tipos de energia final em uso, de modo a se obter um maior impacto em termos de redução no consumo de energia e mitigação de emissões, dois elementos importantes no debate atual sobre combate a mudanças climáticas. / The present energy use structure in the Brazilian industrial sector is a consequence of its historical context within the Brazilian energy sector. This historical background helps to explain some characteristics, like the intensive use of electricity in heating processes, the electrothermia, that lasts until today. The current natural gas production scenario in Brazil is promising, considering the Pre-Salt production, which signals an opportunity to apply this natural resource to final energy uses with higher value, such as final energy for industry. In this context was structured this dissertation, comprising a data analysis technique development and its application to evaluate the insertion of natural gas in the Brazilian industrial sector and its impacts. The developed data analysis technique is constituted by the assessment of four indicators: Additional Demand (DA); Impact on Primary Energy (IEP); Impact on Carbon Emissions (IEC) and Impact on Energy Cost (ICE). In the results obtained, the Non-Ferrous Metals Sector was more prominent as it presented the greater additional demand for natural gas and the largest reductions in primary energy demand, CO2 emissions and energy costs. Other sectors that stood out were the Iron and Steel Sector and the Food and Beverages Sector. Considering 2013 as the base year, the additional demand for natural gas resulting from the substitution of fuel oil and electricity in heating processes would represent a 37% to 42% increase in the demand for natural gas in the Brazilian industrial sector, equivalent to 12% to 14% of Brazil\'s domestic natural gas supply, or 35% to 40% of Gasbol\'s maximum capacity. The impact on primary energy would represent a reduction of 1% to 2% of the primary energy demand of the Brazilian industrial sector. The impact on CO2 emissions would represent a reduction of 4% to 5% of the CO2 emissions associated to energy use of the Brazilian industrial sector. The impact on energy cost would represent a reduction of 2% to 4% of the energy costs associated with electricity and fuel oil of the Brazilian industrial sector. Thus, it is considered that there is an opportunity for the insertion of natural gas in the Brazilian industrial sector resulting from the substitution of fuel oil and electricity by natural gas in thermal processes. Overall, the substitution impacts reduce primary energy demand, CO2 emissions and energy costs. However, this is an energy-saving initiative through energy substitution, being necessary to further promote energy efficiency, for all end uses and types of final energy in use, to multiply the impacts in terms of reducing energy consumption and mitigating emissions, two important elements in the current debate on combating climate change.

Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-03-01T13:26:46Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE DOUTORADO luiz filipe alves cordeiro.pdf: 3367412 bytes, checksum: bb375206b64e3d1952028cf594d8c86e (MD5) / Made available in DSpace on 2016-03-01T13:26:46Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE DOUTORADO luiz filipe alves cordeiro.pdf: 3367412 bytes, checksum: bb375206b64e3d1952028cf594d8c86e (MD5) Previous issue date: 2015-08-20 / O presente estudo, objetiva analisar o atual planejamento do sistema elétrico brasileiro e apontar propostas que visam diversificar a matriz energética brasileira, trazendo como benefícios um sistema robusto que proporcione a redução gradual dos custos de geração, confiabilidade no fornecimento pela tecnologia adequada e por está mais próximo dos centros de carga e por fim, a redução dos impactos ambientais através da redução das emissões de Gases de Efeito Estufa (GEE). Esse trabalho procura avaliar os potenciais do sistema elétrico e propor ações mitigadoras tanto no consumo de energia elétrica com o auxílio das redes neurais artificiais como na geração com a proposta de possibilitar ao Operador Nacional do Sistema (ONS) a otimização do planejamento minimizando CO2. / The present study aims to analyze the current planning of the Brazilian electrical system and point proposals to diversify the Brazilian energy matrix, bringing benefits as a robust system that provides a gradual reduction of generation costs, reliability of supply by appropriate technology and is more near the load centers and finally the reduction of environmental impacts by reducing emissions of Greenhouse Gases (GHGs). This study evaluates the potential of the electric system and propose mitigating actions in power consumption based in artificial neural networks and help to the generation with the proposal to enable the ONS (National Electric System Operator) to optimize the planning minimizing CO2.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-12T13:03:28Z No. of bitstreams: 1 viniciusdealmeidavale.pdf: 2435014 bytes, checksum: 7b5edae6834f8781721577e973cb842a (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T12:13:26Z (GMT) No. of bitstreams: 1 viniciusdealmeidavale.pdf: 2435014 bytes, checksum: 7b5edae6834f8781721577e973cb842a (MD5) / Made available in DSpace on 2016-02-26T12:13:26Z (GMT). No. of bitstreams: 1 viniciusdealmeidavale.pdf: 2435014 bytes, checksum: 7b5edae6834f8781721577e973cb842a (MD5) Previous issue date: 2014-02-24 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Desde o início da industrialização é possível observar um aumento dos níveis de gases de efeito estufa (GEE) causados pelas atividades humanas (WTO, 2009). Diante desse cenário, os problemas em torno dos GEE e as mudanças climáticas relacionadas se tornaram relevantes pontos de debate. As discussões sobre o tema começam a ganhar o cenário mundial a partir do Protocolo de Quioto e estão em voga devido ao fato que o crescimento dos GEE se manteve, mesmo com o avanço e surgimento de políticas climáticas. Além disso, estão em voga devido à globalização acelerada das economias mundiais e à expansão do comércio internacional. Desta forma, o trabalho busca fazer uma investigação empírica sobre as responsabilidades pelas emissões e o comércio internacional para 27 países da União Europeia e 13 países selecionados para o período de 1995 a 2009. O trabalho também permeia questões e discussões em torno das teorias e hipóteses ambientais que envolvem o comércio internacional. Para tanto, foram utilizadas matrizes de insumo-produto para 40 países mais o “restante do mundo” que abrangem o período de 1995 a 2009, provenientes do Projeto WIOD. Os seguintes resultados podem ser destacados: i) a ascensão das emissões de CO2 dos países em desenvolvimento (e.g. Brasil, Rússia, Índia e China); ii) comportamento antagônico entre os Estados Unidos e os BRIC (Brasil, Rússia, Índia e China), com exceção da Índia, em termos dos saldos líquidos de emissões incorporadas no comércio internacional; iii) indícios de que o decréscimo das emissões de alguns países são provenientes de uma maior interação em termos de comércio; e iv) os países desenvolvidos apresentam um processo produtivo interno cada vez menos poluidor e, de forma contrária, os em desenvolvimento apresentam um processo produtivo interno mais poluidor, dado o pareamento entre eles. Além disso, o presente trabalho, por meio dos diferentes resultados, faz uma discussão em torno da teoria da curva de Kuznets ambiental, “pollution haven effect”, “pollution haven hypothesis”, padrões de comércio entre o Norte e o Sul, dentre outras. / Since the beginning of industrialization it is possible to observe an increase in the levels of greenhouse gas (GHG) emissions caused by human activities (WTO, 2009). Given this issues, the problem of greenhouse gas (GHG) and related climate change are relevant points today. Discussions began to gain the attention of the world with the Kyoto Protocol and they are in vogue due to the fact that the growth of GHG remained, even with emergence and advancement of climate policies. Moreover, they are in vogue due the sudden globalization of world economies and the expansion of international trade. Thus, this study seeks to make an empirical investigation of the responsibility for CO2 emissions and international trade for the 27 countries of the European Union and 13 other selected countries for the period of 1995-2009. This paper also permeates issues and discussions about the environmental theories and hypotheses involving international trade. The input-output matrices were used for 40 countries plus the “rest of world” for the period of 1995-2009, through the database of WIOD project. The following results can be highlighted: i) the increase of CO2 emissions in developing countries (e.g. Brazil , Russia, India and China) ; ii) the opposing behavior of the USA and BRIC ( Brazil , Russia, India and China), with the exception of India, in terms of net balances of emissions embodied in international trade; iii) evidence that the decrease of CO2 emissions in some countries comes from greater interaction in terms of trade with other countries; iv) the developed countries have an internal production process increasingly less polluting, and contrary to, developing countries have an internal production process more polluting, given the pairing between them. Furthermore, this study, through the different results, makes a discussion on the theory of environmental Kuznets curve, pollution haven effect, pollution haven hypothesis, trade’s patterns between North and South, and others.

Responsible for one in eight tonnes of national CO₂ emissions, the passenger car sector is pivotal to delivering on UK climate change commitments to avoiding warming of more than 2°C. This thesis provides a clear and quantitative framing of emissions reduction at the sectoral level, by disaggregating global cumulative emissions budgets and pathways associated with a range of probabilities of exceeding 2°C. The relatively low level of abatement currently planned for the UK car sector, it is argued, needs to be significantly increased for the following reasons: (i) a scientific basis in cumulative emissions for sectoral mitigation makes carbon budgets, rather than end point targets (e.g. 2050), of the first importance; (ii) the currently high probability (63%) of exceeding 2°C underpinning the current UK carbon budgets is inconsistent with the UK government’s commitment to avoiding ‘dangerous climate change’; (iii) short-term emissions growth in industrialising countries considerably reduces remaining emissions space for industrialised countries; (iv) very limited scope exists for any large sector to cut emissions by less than the national mean rate of decarbonisation at higher rates of mitigation (around 10% p.a. by the 2020s). The consequences for emissions space in other sectors if international aviation and shipping mitigate less than the mean are quantified. For UK car sector emissions to remain consistent with a low probability of exceeding 2°C while observing these limitations, this analysis finds that planned sectoral mitigation over the coming decade needs to be increased fourfold. Means to address this expected abatement shortfall using readily available technology are investigated using a fleet emissions model to compare the effect on cumulative emissions of changes in a range of fleet parameters (including mean new car bulk emissions factors, vehicle age-proportionate annual distance travelled, and rates of fleet growth and turnover). Pushing existing car technology to the limit of expected short term efficiency gains is found to be insufficient to deliver a pathway with better than 56% probability of exceeding 2°C. Without reduction in aggregate demand for vehicle kilometres in the short term, lower probabilities of 2°C are placed beyond reach. The possibility of rapid step changes in levels of per capita car use is explored in qualitative interviews using narrative storyline scenarios. A range of coercive and voluntary interventions is considered in relation to their potential to overcome the structural and behavioural constraints to rapid transformation of personal travel.

Transportation agencies face a challenging task to repair damaged roads in an aging transportation network with limited funding. In addition, the funding gap is forecasted to continue widening, which has direct impacts on the performance of surface transportation networks and the nation’s economy in the long run. Recently, transportation agencies were required by a newly enacted law to include national performance-based goals, such as environmental sustainability, in their programming and planning efforts for highway repair and rehabilitation. Therefore, the current practice in the area of highway rehabilitation planning is inadequate to handle this task and new practices are needed to improve the performance of transportation networks while maintain the national goal of maximizing environmental sustainability. Accordingly, this dissertation presents an innovative environmental-based decision-support model for planning highway construction programs. The model is developed in three main parts that are designed to: (1) model total vehicle fuel consumption and public benefits/costs of traveling on transportation networks; (2) evaluate the economic and environmental impacts of highway rehabilitation efforts; and (3) develop a multi-objective optimization model to identify and evaluate highway rehabilitation program(s) that are capable of simultaneously minimizing environmental impact and maximizing public benefits of rehabilitation decisions. First, mathematical models were developed to facilitate estimating the total vehicle fuel consumption and public benefits/cost for road users at the network-level. These models are deigned to estimate vehicle fuel consumption rate, tire depreciation cost, and vehicle repair and maintenance cost rate, in terms of major vehicle–road interaction factors, such as vehicle type, speed, and pavement conditions. The developed and statistically validated models are then used to estimate total vehicle fuel consumption and public benefits/costs at the network-level. Second, a new model was developed for evaluating the impact of decision making in highway rehabilitation efforts on greenhouse gas emissions and public travel costs. The model has the capabilities of: (1) identifying candidate rehabilitation treatment alternatives for damaged or aging pavement; (2) evaluating the impact of these treatments on pavement performance; (3) estimating network fuel consumption due to highway rehabilitation decisions; (4) estimating additional public costs as a result of travel-delay during road construction operations; and (5) evaluating the impact of rehabilitation efforts on public benefits expressed as expected savings in road user costs. Third, a multi-objective optimization model was developed to search for and identify highway rehabilitation programs that are capable of minimizing environmental impact in terms of CO2 emissions while maximizing public benefits under budget constraints. This newly developed model enables planners and decision makers to design and implement highway rehabilitation programs that are cost-effective and environmentally-conscious.

Reducing CO2 emission in air transport is the main theme of this master´s thesis. As the public interest in aviation and climate change is world´s growing it could be consider as a hot topic. As a response to public interest was the creation of contracts, standards and limits of carbon dioxide emissions. The master´s thesis is divided into several parts. The first is mapping of global air traffic and carbon dioxide emissions. The second part deals with European approach to solving problems of reducing CO2 emissions follows by description of ICAO Aeroplane CO2 emissions standard. The part of the thesis is the overview of the use of biofuels in aviation and their price. The conclusion summarizes all knowledge learned while working on this thesis.