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Investir dans le stockage géologique du carbone à partir de biomasse : une approche par les options réelles / Invest in biomass with carbon capture and storage : a real option approachLaude, Audrey 02 December 2011 (has links)
La conversion de la biomasse en énergie génère des flux de gaz carbonique qui peuvent être captés,transportés puis stockés dans des strates géologiques. Ce procédé, nommé BCCS (Biomass Carbon Captureand Storage), réduit drastiquement les émissions carbonées et dans certaines conditions le puits artificiel peutstocker plus de carbone que le système de conversion n’en aura produit (émissions négatives). Ainsi, le BCCSrend plus envisageable l’obtention de certains plafonds de concentrations de CO2 atmosphériques inférieurs ouégaux à 450ppm. Des incitations économiques sont nécessaires pour déclencher l’investissement dans leBCCS de la part d’acteurs du secteur privé. Ceux-ci sont confrontés à une incertitude de grande ampleurconcernant le prix du carbone. Nous étudions dans cette thèse le comportement d’un décideur ayant le choixd’investir dans une variante du BCCS, à savoir la production de bioéthanol à partir de betteraves sucrières.Après une analyse déterministe sur un cas réel, nous étudions l’influence de différentes incertitudes sur le profild’investissement via une approche par options réelles. Nous analysons notamment l’influence de l’incertitudedu progrès technique via une loi de Poisson et montrons que l’investisseur tend à attendre l’innovation. Nousdistinguons ensuite progrès de court terme et de long terme. Puis, nous nous intéressons à l’incertitude derégulation climatique. Le marché du carbone est alors modélisé par un mouvement de retour à la moyenneavec des sauts de prix à dates fixes / Using biomass to produce energy emits carbon dioxide. These emissions can be captured, transported andstored into geological formations. This process is named BCCS (Biomass Carbon Capture and Storage). Itleads to massive reductions and the whole system carbon balance system could be negative given specificassumptions, which is called ‘negative emissions’. BCCS may help to achieve low CO2 concentration target,even below the 450ppm threshold. Providing suitable incentives is necessary to trigger private investment.Private investors are facing considerable uncertainty, about the carbon market. We study in this dissertation thebehavior of decision makers who can invest in a specific variant of BCCS, which is the production ofbioethanol coming from sugar beets. After a deterministic analysis based on a real case study, we consider theinfluence of different kinds of uncertainties on the investment profile through a real option approach. Thetechnical progress uncertainty has been modeled with Poisson jumps. We show that investors tend to wait forinnovations. We distinguish two cases depending on the progress rate: early or delayed technical progressrate. First allowance price is driven by geometric Brownian motion. Second, the price follows a mean revertingprocess with jumps at specific fixed dates, to take into account the international round of negotiations aboutclimatic change, as a kind of climate regulation uncertainty.
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Cenários de baixo carbono para o setor energético do Estado de São Paulo / Low Carbon Scenarios for the State of Sao Paulo\'s energy sectorJhonathan Fernandes Torres de Souza 31 January 2019 (has links)
Políticas de mudanças climáticas estabeleceram diversas metas de redução de gases de efeito estufa (GEE) que estão vigentes atualmente. Dentre estas, a 21º Conferência das Partes realizada pela Convenção-Quadro das Nações Unidas sobre Mudança do Clima (em Paris, 2015) foi um marco na universalização dos esforços internacionais, e promoveu o protagonismo regional como suporte ao alcance das metas propostas nas contribuições nacionalmente determinadas. No Estado de São Paulo, diferentemente do quadro nacional, o setor de energia representa mais da metade do saldo total de emissões de GEE. Estudos de baixo carbono para o setor energético têm proposto cenários audaciosos, baseados em tecnologias não plenamente maduras e alta demanda por fontes renováveis. O presente trabalho propõe uma abordagem alternativa visando a mitigação das emissões de GEE, além de analisar os impactos na demanda energética total do Estado, até o presente não analisada na sua totalidade no âmbito regional. O objetivo do estudo foi produzir dois cenários de baixo carbono para o setor energético do Estado de São Paulo até 2050. O primeiro cenário (CBC1) buscou averiguar se é possível cumprir as metas de redução por uma ótica conservadora. O segundo cenário (CBC2), de caráter exploratório, visou ser mais audacioso em relação ao CBC1, tomando medidas radicais para atingir o máximo resultado de mitigação. O cenário de referência (BAU) teve como base a demanda energética final em 2015, projetada até 2050 através do Plano Decenal de Expansão de Energia. As tecnologias de baixo carbono no CBC1 foram levantadas na base de metodologias provadas para o Mecanismo de Desenvolvimento Limpo (MDL), e expandidas para o CBC2 com base em uma revisão da literatura. No CBC1, as três medidas de mitigação propostas seriam capazes de reduzir 16% das emissões totais do cenário BAU no período de análise, entretanto as emissões continuariam no mínimo 19% acima da emissão do setor no ano base de 2005. Por outro lado, o CBC2 possui seis medidas capazes de reduzir 69% das emissões do cenário BAU e, a partir de 2044, as emissões líquidas são negativas, disponibilizando aos demais setores 5% da mitigação total até 2050. A implantação do baixo carbono também reduz a demanda total energética em até 2% no ano final, entretanto há demandas específicas, como a de biodiesel, que são consideravelmente aumentadas. O trabalho discute os resultados à luz da literatura e apresenta as principais barreiras impostas aos cenários propostos, assim como as incertezas e limitações da análise. Além disto, contribui metodologicamente para que futuros estudos possam avaliar a possibilidade de cumprimento de metas de redução em outras regiões ou setores da economia, considerando uma ótica conservadora baseada no MDL / Climate change policies have established several greenhouse gas (GHG) reduction targets. Among them, the 21st Conference of the Parties of the United Nation Framework Convention on Climate Change (held in Paris in 2015) was a milestone for the universalization of international efforts, and the promotion of a regional activism in supporting to the goals proposed by the national determined contributions. In the State of Sao Paulo, in opposition to the national profile, the energy sector represents more than half of the total GHG emissions. Low carbon studies for the energy sector have proposed audacious scenarios based on not yet mature technologies and high renewable energy demand. The present work proposes an alternative GHG mitigation approach, and in addition it analyzes the impacts on Sao Paulos total energy demand, which was not yet entirely analyzed by other regional studies. The study has aimed to produce two low carbon scenarios for State of Sao Paulos energy sector by 2050. The first scenario (LCS1) attempted to verify whether GHG reduction targets can be reached by a conservative approach. The second scenario (LCS2) is exploratory and has aimed to be more audacious than LCS2, through radical measures aiming to the maximum mitigation result. The business-as-usual (BAU) scenario has been based on the States final energy demand, beginning in 2015 and forecasted until 2050 with data from the Decennial Energy Expansion Plan. Low carbon technologies for LCS1 have been selected among the Clean Development Mechanism (CDM) proven methodologies. The framework has been expanded for LCS2 based on a literature review. On the one hand, three measures proposed in LCS1 would be able to reduce 16% of BAU total emission in the analyzed period; however, emissions remain at least 19% above 2005 baseline emission. On the other hand, LCS2 has six measures able to reduce 69% of BAU total emissions and, from 2044; net emissions would be negative, which enables 5% of total mitigation for other sectors by 2050. The low carbon implementation also reduces total energy up to 2% in the 2050, although there are specific demands, such as biodiesel, that will significantly increase. The work discusses the results vis-à-vis the literature and presents the main barriers imposed to low carbon scenarios, as well as uncertainties and limitations of the analysis. Moreover, it methodologically contributes to future studies that may assess the potential of a conservative approach based on CDM, regarding other regional and sectorial contexts
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Avaliação do ciclo de vida e pegada de carbono da reciclagem de CO2 em um sistema de produção de etanol de cana-de-açúcar / Life cycle assessment and carbon footprint of CO2 recycling in a sugarcane based ethanol production systemFunes, Rodrigo Hartkoff 02 March 2016 (has links)
A captura e uso do dióxido de carbono é uma das formas de ajudar a frear as emissões de gases do efeito estufa (GEE) e destiná-lo a um fim útil. Um possível uso para o CO2 seria como fertilizante agrícola, uma vez que as plantas quando em maiores concentrações deste gás ceteris paribus apresentam um incremento de biomassa. Os biocombustíveis são opções que contribuem para a mitigação das mudanças climáticas em detrimento ao uso de combustíveis fósseis e entre os biocombustíveis a produção de etanol a partir de cana-de-açúcar se destaca devido a vantagens quanto à emissão de GEE e energia acumulada. Essas vantagens podem ser ainda maiores com o uso do CO2 proveniente de suas biorrefinarias na forma de insumo agrícola. O objetivo deste trabalho é avaliar esta nova técnica de uso de carbono por meio da metodologia da Avaliação do Ciclo de Vida (ACV) e da pegada de carbono de produtos para encontrar suas contribuições no balanço de energia e carbono do sistema. Um modelo de dispersão de gases foi utilizado para saber se é possível manter a concentração de CO2 no campo dentro dos parâmetros necessários para o incremento de biomassa. A análise indica que um sistema adaptado de irrigação por gotejamento pode manter a concentração deste gás dentro do nível desejado quando a emissão fica em 22,5 g ha-1s-1, mas que uma mesma área não é autossuficiente para o fornecimento de CO2 para fase de crescimento dos colmos. Através da ACV e da pegada de carbono da cana-de-açúcar em um cenário onde o incremento de biomassa é médio em relação aos experimentos encontrados, a tecnologia reduz em 13,5% a demanda de energia e 11,8% as emissões de GEE por MJ de bioenergia produzida se comparada ao sistema tradicional. O balanço de energia para o sistema tradicional e com reciclagem de CO2 foi de 170 GJ/ha e 206 GJ/ha, enquanto o balanço de carbono foi de -13950 kgCO2eq/ha e -17019 kgCO2eq/ha, respectivamente. Considerando as possíveis variações de incremento de biomassa, para cada MJ produzido a emissão de GEE pode variar em 8,9% e o consumo de energia em 10,9%. Essa nova técnica de uso de carbono do ponto vista teórico pode ser aplicada em campo e implica em um aumento entre 13 a 30% do balanço de energia para um hectare de cana-de-açúcar, consequentemente uma menor quantidade de terra será necessária para atingir as metas energéticas estipuladas / Carbon capture and use (CCU) may slow down greenhouse gas (GHG) emissions and direct them to a useful end. A possible CO2 application is as plant fertilizer because ceteris paribus biomass increases when plants grow under high CO2 concentrations. Compared to fossil fuels, biofuels mitigate climate change, and the use of sugarcane ethanol stands out due to its low lifecycle GHG emissions and Cumulative Energy Demand (CED). Such benefits might be enhanced with the use of CO2 from the biorefinery as a crop fertilizer. The objective of this study is evaluating this new CCU scheme based on a life cycle assessment (LCA) and a carbon footprint to determine its energy and carbon balances. An air pollution dispersion model was used to verify whether it is possible to maintain the CO2 concentration on the field so that biomass increase takes place. The analysis demonstrates that a drip irrigation system can keep the concentration of gas within the desired level when the emission is 22.5 g ha-1s-1, but that the same area is not self sufficient to supply CO2 for the complete growth phase of the stalks. Results from the LCA and the carbon footprint demonstrate that compared to the traditional system, the scheme decreases CED and GHG emissions by 13,5% and 11,8%, respectively. The energy balance of the traditional and the recycling system were 170 GJ/ha and 206 GJ/ha, respectively, whereas the carbon balance was -13,950 kgCO2eq/ha and -17,019 kgCO2eq/ha, respectively. Considering the range of growth responses, for each MJ produced GHG emissions vary 8,9% whereas energy consumption varies 10,9%. These CCU scheme might be applied on the field and implies in improvements between 13 and 30% in the energy balance of 1ha of sugarcane; thus, a smaller land area will be needed than with the traditional system to achieve the energy goals
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Avaliação do ciclo de vida e pegada de carbono da reciclagem de CO2 em um sistema de produção de etanol de cana-de-açúcar / Life cycle assessment and carbon footprint of CO2 recycling in a sugarcane based ethanol production systemRodrigo Hartkoff Funes 02 March 2016 (has links)
A captura e uso do dióxido de carbono é uma das formas de ajudar a frear as emissões de gases do efeito estufa (GEE) e destiná-lo a um fim útil. Um possível uso para o CO2 seria como fertilizante agrícola, uma vez que as plantas quando em maiores concentrações deste gás ceteris paribus apresentam um incremento de biomassa. Os biocombustíveis são opções que contribuem para a mitigação das mudanças climáticas em detrimento ao uso de combustíveis fósseis e entre os biocombustíveis a produção de etanol a partir de cana-de-açúcar se destaca devido a vantagens quanto à emissão de GEE e energia acumulada. Essas vantagens podem ser ainda maiores com o uso do CO2 proveniente de suas biorrefinarias na forma de insumo agrícola. O objetivo deste trabalho é avaliar esta nova técnica de uso de carbono por meio da metodologia da Avaliação do Ciclo de Vida (ACV) e da pegada de carbono de produtos para encontrar suas contribuições no balanço de energia e carbono do sistema. Um modelo de dispersão de gases foi utilizado para saber se é possível manter a concentração de CO2 no campo dentro dos parâmetros necessários para o incremento de biomassa. A análise indica que um sistema adaptado de irrigação por gotejamento pode manter a concentração deste gás dentro do nível desejado quando a emissão fica em 22,5 g ha-1s-1, mas que uma mesma área não é autossuficiente para o fornecimento de CO2 para fase de crescimento dos colmos. Através da ACV e da pegada de carbono da cana-de-açúcar em um cenário onde o incremento de biomassa é médio em relação aos experimentos encontrados, a tecnologia reduz em 13,5% a demanda de energia e 11,8% as emissões de GEE por MJ de bioenergia produzida se comparada ao sistema tradicional. O balanço de energia para o sistema tradicional e com reciclagem de CO2 foi de 170 GJ/ha e 206 GJ/ha, enquanto o balanço de carbono foi de -13950 kgCO2eq/ha e -17019 kgCO2eq/ha, respectivamente. Considerando as possíveis variações de incremento de biomassa, para cada MJ produzido a emissão de GEE pode variar em 8,9% e o consumo de energia em 10,9%. Essa nova técnica de uso de carbono do ponto vista teórico pode ser aplicada em campo e implica em um aumento entre 13 a 30% do balanço de energia para um hectare de cana-de-açúcar, consequentemente uma menor quantidade de terra será necessária para atingir as metas energéticas estipuladas / Carbon capture and use (CCU) may slow down greenhouse gas (GHG) emissions and direct them to a useful end. A possible CO2 application is as plant fertilizer because ceteris paribus biomass increases when plants grow under high CO2 concentrations. Compared to fossil fuels, biofuels mitigate climate change, and the use of sugarcane ethanol stands out due to its low lifecycle GHG emissions and Cumulative Energy Demand (CED). Such benefits might be enhanced with the use of CO2 from the biorefinery as a crop fertilizer. The objective of this study is evaluating this new CCU scheme based on a life cycle assessment (LCA) and a carbon footprint to determine its energy and carbon balances. An air pollution dispersion model was used to verify whether it is possible to maintain the CO2 concentration on the field so that biomass increase takes place. The analysis demonstrates that a drip irrigation system can keep the concentration of gas within the desired level when the emission is 22.5 g ha-1s-1, but that the same area is not self sufficient to supply CO2 for the complete growth phase of the stalks. Results from the LCA and the carbon footprint demonstrate that compared to the traditional system, the scheme decreases CED and GHG emissions by 13,5% and 11,8%, respectively. The energy balance of the traditional and the recycling system were 170 GJ/ha and 206 GJ/ha, respectively, whereas the carbon balance was -13,950 kgCO2eq/ha and -17,019 kgCO2eq/ha, respectively. Considering the range of growth responses, for each MJ produced GHG emissions vary 8,9% whereas energy consumption varies 10,9%. These CCU scheme might be applied on the field and implies in improvements between 13 and 30% in the energy balance of 1ha of sugarcane; thus, a smaller land area will be needed than with the traditional system to achieve the energy goals
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Poli (l?quidos i?nicos) celul?sicos aplicados como catalisadores heterog?neos para transforma??o qu?mica do CO2 em carbonatos c?clicosRodrigues, Daniela Maffi 27 July 2018 (has links)
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Previous issue date: 2018-07-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Carbon capture and storage (CCS) and carbon capture and utilisation(CCU) technologies has been pointed out as possibilities to mitigate the effects caused by the massiverelease of CO2 into the atmosphere. The use of CO2 in cycloaddition reactions toepoxides obtaining cyclic carbonates is an interesting possibility to reduce CO2emission. Cyclic carbonates are products of great applicability as solvents in the chemical industry and are used as raw material for a wide range of products. Meanwhile, the use of CO2 for a cycloaddition reaction requires a large amount of energy being necessary the use of catalysts in order to optimize such reactions. Poly (ionic liquids) (PIL) are alternative catalysts due its selective, recyclability and conversion. In this work, cellulosic poly(ionic liquids) (CPIL) obtained from rice husk were testedas heterogeneous catalyst. Cellulose extraction was carried out by chemical method. A chemical modification of the cellulose fibers was carried out by the treatment with citric acid and functionalization with 3 mmol of the ionic liquids BMIM Cl, TBAB, TBPB and BMPYRR to form CPIL-BMIM, CPIL-TBA, CPIL-TBP and CPIL-BMPYRR), without addition of solvents. Cyclo addition reactions were carried out with propylene and styrene oxides with different CO2 pressures(25, 30 and 40 bar) and temperatures (90, 110 and 120 ?C) for 6 h. The obtained product was characterized by gas chromatography (GC), Fourier Transform Infrared Spectroscopy(FTIR)and Nuclear Magnetic Resonance (1H NMR). The results showed better yields for CPIL-TBP and CPIL-TBA, whose values were 53.2% and 39% respectively for propylene carbonate and 67.3% for styrene carbonate using CPIL-TBP. When the ZnBr2 cocatalyst was used, there was an increase in the catalytic activity of these catalysts. For CPIL-TBP the yields were 71.4% for propylene carbonate and 78.7% for styrene carbonate. For CPIL-TBA the increase in propylene carbonate yield was 67.7%. / O uso das tecnologias de captura e armazenamento de carbono (CCS) e de captura utiliza??o do carbono (CCU) v?m sendo apontadas como possibilidades para mitigar os efeitos causados pela libera??o deliberada de elevadas concentra??es de CO2 na atmosfera. A utiliza??o do CO2 em rea??es de cicloadi??o em ep?xidos para obter carbonatos c?clicos vem se mostrando uma possibilidade interessante para reduzir a emiss?o de CO2 na atmosfera. Os carbonatos c?clicos s?o produtos de grande aplicabilidade como solventes na ind?stria qu?mica e s?o utilizados como mat?ria prima para uma vasta gama de produtos. Entretanto, o CO2 apresenta baixa reatividade tornando-se necess?rio o uso de catalisadores para otimizar tais rea??es. Os poli(l?quidos i?nicos) (PILs) v?m se mostrando como poss?veis catalisadores alternativos, demonstrando-se seletivos, recicl?veis e gerando consider?vel convers?o. Neste trabalho foram testados poli(l?quidos i?nicos) celul?sicos (CPIL), obtidos a partir da casca do arroz, como catalisador heterog?neo. A extra??o da celulose foi realizada por um m?todo qu?mico. A modifica??o qu?mica das fibras de celulose foi realizada a partir do tratamento com ?cido c?trico e a funcionaliza??o desta com 3 mmol dos l?quidos i?nicos BMIM Cl, TBAB, TBPB e BMPYRR formando CPIL-BMIM, CPIL-TBA, CPIL-TBP e CPIL-BMPYRR. As rea??es de cicloadi??o foram realizadas com os ?xidos de propileno e estireno com diferentes press?es de CO2 (15, 25, 30 e 40 bar) e temperaturas (90, 110, 120 e 130?C) durante (3, 6 e 9h), todas as rea??es foram realizadas sem a utiliza??o de solventes. O produto obtido foi caracterizado por cromatografia gasosa (CG) , espectroscopia de infravermelho com transformada de Fourier (FTIR) e Resson?ncia Magn?tica Nuclear (1H RMN). Os resultados demonstraram melhores rendimentos para CPIL-TBP e CPIL-TBA, cujos valores foram de 53,2% e 39% respectivamente para o carbonato de propileno e de 67,3% para o carbonato de estireno utilizando o CPIL-TBP. Quando o cocatalisador ZnBr2 foi utilizado, houve um aumento na a atividade catal?tica destes catalisadores, para o CPIL-TBP os rendimentos foram de 71,4 % para o carbonato de propileno e 78,7% para o carbonato de estireno. Para o CPIL-TBA o aumento no rendimento de carbonato de propileno foi de 67,7%.
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Cenários de baixo carbono para o setor energético do Estado de São Paulo / Low Carbon Scenarios for the State of Sao Paulo\'s energy sectorSouza, Jhonathan Fernandes Torres de 31 January 2019 (has links)
Políticas de mudanças climáticas estabeleceram diversas metas de redução de gases de efeito estufa (GEE) que estão vigentes atualmente. Dentre estas, a 21º Conferência das Partes realizada pela Convenção-Quadro das Nações Unidas sobre Mudança do Clima (em Paris, 2015) foi um marco na universalização dos esforços internacionais, e promoveu o protagonismo regional como suporte ao alcance das metas propostas nas contribuições nacionalmente determinadas. No Estado de São Paulo, diferentemente do quadro nacional, o setor de energia representa mais da metade do saldo total de emissões de GEE. Estudos de baixo carbono para o setor energético têm proposto cenários audaciosos, baseados em tecnologias não plenamente maduras e alta demanda por fontes renováveis. O presente trabalho propõe uma abordagem alternativa visando a mitigação das emissões de GEE, além de analisar os impactos na demanda energética total do Estado, até o presente não analisada na sua totalidade no âmbito regional. O objetivo do estudo foi produzir dois cenários de baixo carbono para o setor energético do Estado de São Paulo até 2050. O primeiro cenário (CBC1) buscou averiguar se é possível cumprir as metas de redução por uma ótica conservadora. O segundo cenário (CBC2), de caráter exploratório, visou ser mais audacioso em relação ao CBC1, tomando medidas radicais para atingir o máximo resultado de mitigação. O cenário de referência (BAU) teve como base a demanda energética final em 2015, projetada até 2050 através do Plano Decenal de Expansão de Energia. As tecnologias de baixo carbono no CBC1 foram levantadas na base de metodologias provadas para o Mecanismo de Desenvolvimento Limpo (MDL), e expandidas para o CBC2 com base em uma revisão da literatura. No CBC1, as três medidas de mitigação propostas seriam capazes de reduzir 16% das emissões totais do cenário BAU no período de análise, entretanto as emissões continuariam no mínimo 19% acima da emissão do setor no ano base de 2005. Por outro lado, o CBC2 possui seis medidas capazes de reduzir 69% das emissões do cenário BAU e, a partir de 2044, as emissões líquidas são negativas, disponibilizando aos demais setores 5% da mitigação total até 2050. A implantação do baixo carbono também reduz a demanda total energética em até 2% no ano final, entretanto há demandas específicas, como a de biodiesel, que são consideravelmente aumentadas. O trabalho discute os resultados à luz da literatura e apresenta as principais barreiras impostas aos cenários propostos, assim como as incertezas e limitações da análise. Além disto, contribui metodologicamente para que futuros estudos possam avaliar a possibilidade de cumprimento de metas de redução em outras regiões ou setores da economia, considerando uma ótica conservadora baseada no MDL / Climate change policies have established several greenhouse gas (GHG) reduction targets. Among them, the 21st Conference of the Parties of the United Nation Framework Convention on Climate Change (held in Paris in 2015) was a milestone for the universalization of international efforts, and the promotion of a regional activism in supporting to the goals proposed by the national determined contributions. In the State of Sao Paulo, in opposition to the national profile, the energy sector represents more than half of the total GHG emissions. Low carbon studies for the energy sector have proposed audacious scenarios based on not yet mature technologies and high renewable energy demand. The present work proposes an alternative GHG mitigation approach, and in addition it analyzes the impacts on Sao Paulos total energy demand, which was not yet entirely analyzed by other regional studies. The study has aimed to produce two low carbon scenarios for State of Sao Paulos energy sector by 2050. The first scenario (LCS1) attempted to verify whether GHG reduction targets can be reached by a conservative approach. The second scenario (LCS2) is exploratory and has aimed to be more audacious than LCS2, through radical measures aiming to the maximum mitigation result. The business-as-usual (BAU) scenario has been based on the States final energy demand, beginning in 2015 and forecasted until 2050 with data from the Decennial Energy Expansion Plan. Low carbon technologies for LCS1 have been selected among the Clean Development Mechanism (CDM) proven methodologies. The framework has been expanded for LCS2 based on a literature review. On the one hand, three measures proposed in LCS1 would be able to reduce 16% of BAU total emission in the analyzed period; however, emissions remain at least 19% above 2005 baseline emission. On the other hand, LCS2 has six measures able to reduce 69% of BAU total emissions and, from 2044; net emissions would be negative, which enables 5% of total mitigation for other sectors by 2050. The low carbon implementation also reduces total energy up to 2% in the 2050, although there are specific demands, such as biodiesel, that will significantly increase. The work discusses the results vis-à-vis the literature and presents the main barriers imposed to low carbon scenarios, as well as uncertainties and limitations of the analysis. Moreover, it methodologically contributes to future studies that may assess the potential of a conservative approach based on CDM, regarding other regional and sectorial contexts
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Clean Coal And Carbon Capture And Storage Technology Roadmap Of TurkeyVural, Asli 01 February 2010 (has links) (PDF)
The present study presents a draft national CCT (Clean Coal Technologies) and CCS (Carbon Capture and Storage) technology roadmap to policy makers. Various technical and non-technical (economic and social) challenges that currently prevent CCT and CCS from being a widely used commercial technology are discussed and the goals for each research pathway are defined. The process of creating the roadmap started with a review and assessment of the existing national and international technology roadmaps which represent a global picture of the state of the art and national and international plans for future on CCT and CCS research development, demonstration and deployment (R& / D& / D). Following this step, the national situation, capacities and priorities were examined. Finally, R& / D& / D actions discussed in the existing roadmaps and/or new actions were carefully selected and suggested as a draft Turkish CCT and CCS Roadmap that needs further development and discussion by the input of interdisciplinary national stakeholders. As a conclusion a number of technical and non-technical suggestions are delivered.
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Understanding the plume dynamics and risk associated with CO₂ injection in deep saline aquifersGupta, Abhishek Kumar 12 July 2011 (has links)
Geological sequestration of CO₂ in deep saline reservoirs is one of the ways to reduce its continuous emission into the atmosphere to mitigate the greenhouse effect. The effectiveness of any CO₂ sequestration operation depends on pore volume and the sequestration efficiency of the reservoir. Sequestration efficiency is defined here as the maximum storage with minimum risk of leakage to the overlying formations or to the surface. This can be characterized using three risk parameters i) the time the plume takes to reach the top seal; ii) maximum lateral extent of the plume and iii) the percentage of mobile CO₂ present at any time. The selection among prospective saline reservoirs can be expedited by developing some semi-analytical correlations for these risk parameters which can be used in place of reservoir simulation study for each and every saline reservoir. Such correlations can reduce the cost and time for commissioning a geological site for CO₂ sequestration. To develop such correlations, a database has been created from a large number of compositional reservoir simulations for different elementary reservoir parameters including porosity, permeability, permeability anisotropy, reservoir depth, thickness, dip, perforation interval and constant pressure far boundary condition. This database is used to formulate different correlations that relate the sequestration efficiency to reservoir properties and operating conditions. The various elementary reservoir parameters are grouped together to generate different variants of gravity number used in the correlations. We update a previously reported correlation for time to hit the top seal and develop new correlations for other two parameters using the newly created database. A correlation for percentage of trapped CO₂ is also developed using a previously created similar database. We find that normalizing all risk parameters with their respective characteristic values yields reasonable correlations with different variants of gravity number. All correlations confirm the physics behind plume movement in a reservoir. The correlations reproduce almost all simulation results within a factor of two, and this is adequate for rapid ranking or screening of prospective storage reservoirs. CO₂ injection in saline reservoirs on the scale of tens of millions of tonnes may result in fracturing, fault activation and leakage of brine along conductive pathways. Critical contour of overpressure (CoP) is a convenient proxy to determine the risk associated with pressure buildup at different location and time in the reservoir. The location of this contour varies depending on the target aquifer properties (porosity, permeability etc.) and the geology (presence and conductivity of faults). The CoP location also depends on relative permeability, and we extend the three-region injection model to derive analytical expressions for a specific CoP as a function of time. We consider two boundary conditions at the aquifer drainage radius, constant pressure or an infinite aquifer. The model provides a quick tool for estimating pressure profiles. Such tools are valuable for screening and ranking sequestration targets. Relative permeability curves measured on samples from seven potential storage formations are used to illustrate the effect on the CoPs. In the case of a constant pressure boundary and constant rate injection scenario, the CoP for small overpressures is time-invariant and independent of relative permeability. Depending on the relative values of overall mobilities of two-phase region and of brine region, the risk due to a critical CoP which lies in the two-phase region can either increase or decrease with time. In contrast, the risk due to a CoP in the drying region always decreases with time. The assumption of constant pressure boundaries is optimistic in the sense that CoPs extend the least distance from the injection well. We extend the analytical model to infinite-acting aquifers to get a more widely applicable estimate of risk. An analytical expression for pressure profile is developed by adapting water influx models from traditional reservoir engineering to the "three-region" saturation distribution. For infinite-acting boundary condition, the CoP trends depend on same factors as in the constant pressure case, and also depend upon the rate of change of aquifer boundary pressure with time. Commercial reservoir simulators are used to verify the analytical model for the constant pressure boundary condition. The CoP trends from the analytical solution and simulation results show a good match. To achieve safe and secure CO₂ storage in underground reservoirs several state and national government agencies are working to develop regulatory frameworks to estimate various risks associated with CO₂ injection in saline aquifers. Certification Framework (CF), developed by Oldenburg et al (2007) is a similar kind of regulatory approach to certify the safety and effectiveness of geologic carbon sequestration sites. CF is a simple risk assessment approach for evaluating CO₂ and brine leakage risk associated only with subsurface processes and excludes compression, transportation, and injection-well leakage risk. Certification framework is applied to several reservoirs in different geologic settings. These include In Salah CO₂ storage project Krechba, Algeria, Aquistore CO₂ storage project Saskatchewan, Canada and WESTCARB CO₂ storage project, Solano County, California. Compositional reservoir simulations in CMG-GEM are performed for CO₂ injection in each storage reservoir to predict pressure build up risk and CO₂ leakage risk. CO₂ leakage risk is also estimated using the catalog of pre-computed reservoir simulation results. Post combustion CO₂ capture is required to restrict the continuous increase of carbon content in the atmosphere. Coal fired electricity generating stations are the dominant players contributing to the continuous emissions of CO₂ into the atmosphere. U.S. government has planned to install post combustion CO₂ capture facility in many coal fired power plants including W.A. Parish electricity generating station in south Texas. Installing a CO₂ capture facility in a coal fired power plant increases the capital cost of installation and operating cost to regenerate the turbine solvent (steam or natural gas) to maintain the stripper power requirement. If a coal-fired power plant with CO₂ capture is situated over a viable source for geothermal heat, it may be desirable to use this heat source in the stripper. Geothermal brine can be used to replace steam or natural gas which in turn reduces the operating cost of the CO₂ capture facility. High temperature brine can be produced from the underground geothermal brine reservoir and can be injected back to the reservoir after the heat from the hot brine is extracted. This will maintain the reservoir pressure and provide a long-term supply of hot brine to the stripper. Simulations were performed to supply CO₂ capture facility equivalent to 60 MWe electric unit to capture 90% of the incoming CO₂ in WA Parish electricity generating station. A reservoir simulation study in CMG-GEM is performed to evaluate the feasibility to recycle the required geothermal brine for 30 years time. This pilot study is scaled up to 15 times of the original capacity to generate 900 MWe stripping system to capture CO₂ at surface. / text
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A Multi-Criteria Decision Analysis and Risk Assessment Model for Carbon Capture and StorageChoptiany, John, Michael, Humphries 29 November 2012 (has links)
Currently several disparate and incomplete approaches are being used to analyse and make decisions on the complex methodology of carbon capture and storage (CCS). A literature review revealed that, as CCS is a new and complex technology, there is no agreed-upon thorough assessment method for high-level CCS decisions. Therefore, a risk model addressing these weaknesses was created for assessing complex CCS decisions using a multi-criteria decision analysis approach (MCDA). The model is aimed at transparently and comprehensively assessing a wide variety of heterogeneous CCS criteria to provide insights into and to aid decision makers in making CCS-specific decisions.
The risk model includes a variety of tools to assess heterogeneous CCS criteria from the environmental, social, economic and engineering fields. The model uses decision trees, sensitivity analysis and Monte Carlo simulation in combination with utility curves and decision makers’ weights to assess decisions based on data and situational uncertainties. Elements in the model have been used elsewhere but are combined here in a novel way to address CCS decisions.
Three case studies were developed to run the model in scenarios using expert opinion, project-specific data, literature reviews, and engineering reports from Alberta, Saskatchewan and Europe. In collaboration with Alberta Innovates Technology Futures, a pilot study was conducted with CCS experts in Alberta to assess how they would rank the importance of CCS criteria to a project selection decision. The MCDA model was run using experts’ criteria weights to determine how CCS projects were ranked by different experts.
The model was well received by the CCS experts who believed that it could be adapted and commercialized to meet many CCS decision problems. The survey revealed a wide range in experts’ understanding of CCS criteria. Experts also placed more emphasis on criteria from within their field of expertise, although economic criteria dominated weights overall. The results highlight the benefit of a model that clearly demonstrates the trade-offs between projects under uncertain conditions. The survey results also revealed how simple decision analyses can be improved by including more transparent methods, interdisciplinary criteria and sensitivity analysis to produce more comprehensive assessments.
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Three essays on energy efficiency and environmental policies in CanadaGamtessa, Samuel Faye Unknown Date
No description available.
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