This study determined the state of the practice and emerging trends in developing greenhouse gas (GHG) thresholds of significance for use under the California Environmental Policy Act (CEQA). To describe the adopted, proposed or considered approaches for developing thresholds of significance by air districts and the thought processes behind these decisions, information was obtained through surveys and phone interviews from twelve employees of air districts in California, State agencies, and consultants that are considered experts on this issue. The results of this study include a comparison matrix of the approaches of the three air districts that have adopted or proposed GHG thresholds of significance, and identification of the common themes from air districts’ responses that do not have adopted or proposed thresholds. While the development of GHG thresholds of significance is an evolving practice, emerging trends in this practice were identified. These trends include providing flexibility in options, an emphasis on programmatic approaches and a preference of including bright-line thresholds and efficiency thresholds. Furthermore, this paper concludes that while the three air districts that have proposed or adopted thresholds have laid the groundwork for other districts, some of the approaches or the thresholds themselves may not be easily transferable to other districts based on regional differences. This research provides insight into how GHG emissions might be addressed in CEQA documents throughout the State.

Sweden has recently increased its efforts to reach net-zero greenhouse gas emission by 2045.The purpose of this study is to assess the feasibility for Bollnäs municipality to meet itsenvironmental goals through the conversion of its current fleet to a Natural Gas Vehicle basedfleet. A CO2 emission-based comparison has been used to estimate from an environmentalstandpoint the viability of biogas as the main fuel for the Bollnäs municipality fleet. Theresults have shown how a compressed natural gas (CNG) based fleet would lower by morethan five times the estimated CO2 emission of the current fleet. The viability of a biogas fleethas been proven and further results have shown how if the CNG fuel was produced from100% renewable resources the environmental impact would be even lower. The results havealso shown how Electric Vehicles (EV) and Hydrogenated Vegetable Oil (HVO) from 100%renewable resources could be viable environmental alternatives but it requires furtherinvestigation from an infrastructure and economic standpoint. / <p>2021-06-04</p>

Access to modern energy services derived from renewable sources is a prerequisite, not only for economic growth, rural development and sustainable development, but also for energy security and climate change mitigation. The least developed countries (LDCs) primarily use traditional biomass and have little access to commercial energy sources. They are more vulnerable to problems relating to energy security, air pollution, and the need for hard-cash currency to import fossil fuels. This thesis evaluates sugarcane-molasses bioethanol, a renewable energy source with the potential to be used as a transport fuel in Nepal. Sustainability aspects of molasses-based ethanol have been analyzed. Two important indicators for sustainability, viz. net energy and greenhouse gas (GHG) balances have been used to assess the appropriateness of bioethanol in the life cycle assessment (LCA) framework. This thesis has found that the production of bioethanol is energy-efficient in terms of the fossil fuel inputs required to produce it. Life cycle greenhouse gas (GHG) emissions from production and combustion are also lower than those of gasoline. The impacts of important physical and market parameters, such as sugar cane productivity, the use of fertilizers, energy consumption in different processes, and price have been observed in evaluating the sustainability aspects of bioethanol production. The production potential of bioethanol has been assessed. Concerns relating to the fuel vs. food debate, energy security, and air pollution have also been discussed. The thesis concludes that the major sustainability indicators for molasses ethanol in Nepal are in line with the goals of sustainable development. Thus, Nepal could be a good example for other LDCs when favorable governmental policy, institutional set-ups, and developmental cooperation from donor partners are in place to strengthen the development of renewable energy technologies. / QC 20101029

In this paper, biochemicals with the potential to substitute fossil reference chemicals in Germany were identified using technological readiness and substitution potential criteria. Their greenhouse gas (GHG) emissions were quantified by using life cycle assessments (LCA) and their economic viabilities were determined by comparing their minimum selling prices with fossil references’ market prices. A bottom up mathematical optimization model, BioENergy OPTimization (BENOPT) was used to investigate the GHG abatement potential and the corresponding abatement costs for the biochemicals up to 2050. BENOPT determines the optimal biomass allocation pathways based on maximizing GHG abatement under resource, capacity, and demand constraints. The identified biochemicals were bioethylene, succinic acid, polylactic acid (PLA), and polyhydroxyalkanoates (PHA). Results show that only succinic acid is economically competitive. Bioethylene which is the least performing in terms of economics breaks even at a carbon price of 420 euros per ton carbon dioxide equivalent (€/tCO2eq). With full tax waivers, a carbon price of 134 €/tCO2eq is necessary. This would result in positive margins for PHA and PLA of 12% and 16%, respectively. From the available agricultural land, modeling results show high sensitivity to assumptions of carbon dioxide (CO2) sequestration in biochemicals and integrated biochemicals production. GHG abatement for scenarios where these assumptions were disregarded and where they were collectively taken into account increased by 370% resulting in a 75% reduction in the corresponding GHG abatement costs.

At present, it is difficult and costly to measure directly greenhouse gas (GHG) emissions from the wastewater treatment system. Application of model will reduce measurement cost and quickly obtain the forecast data set of GHG emissions. This study developed a mathematical model for both steady and dynamic states to calculate GHG (CO2, CH4, and N2O) emissions from wastewater treatment systems for industrial paper processing. These models are constructed based on mass balance equations of species, including substrate balance equations, biomass balance equations for reactors of treatment systems, stoichiometric coefficiences of species in biochemical reactions and biological processes. The obtained equations were solved based on algorithm of Runge-Kutta and the model was programmed by MATLAB. Results of applying the model to calculate GHG emissions from the paper industrial wastewater treatment system at Bai Bang and Tan Mai plants are as follows: total GHG emissions and emission factor are 3,070.3 kgCO2-eq/day, 0.38 kgCO2- eq/m3, respectively for Bai Bang plant (8,000 m3/day) and 7,413.6 kgCO2-eq/day, 0.74 kgCO2- eq/m3, respectively for Tan Mai plant (10,000 m3/day). The research evaluated a number of influencing factors, such as temperature, flow rate of influent, and substrate concentrations, to GHG emissions at the Tan Mai paper plant. / Hiện nay, việc đo đạc trực tiếp phát thải khí nhà kính (KNK) từ hệ thống xử lý nước thải còn khó khăn và tốn kém. Việc áp dụng mô hình sẽ giảm được chi phí đo đạc và nhanh chóng có được bộ số liệu dự báo một cách tương đối về phát thải KNK. Nghiên cứu đã thiết lập được mô hình toán ở trạng thái ổn định và trạng thái không ổn định để tính toán phát thải khí nhà kính (CO2, CH4, N2O) từ hệ thống xử lý nước thải sản xuất giấy. Các mô hình này dựa trên các phương trình cân bằng chất của các cấu tử bao gồm các phương trình cân bằng cơ chất, các phương trình cân bằng sinh khối trong các bể phản ứng và các hệ số tỷ lượng của các chất tham gia các phản ứng sinh hóa. Các phương trình được giải bằng thuật toán Runge-Kutta và mô hình được lập trình trên ngôn ngữ MATLAB. Mô hình được áp dụng tính toán phát thải khí nhà kính từ hệ thống xử lý nước thải tại nhà máy giấy Bãi Bằng và nhà máy giấy Tân Mai, được kết quả như sau: tổng phát thải khí nhà kính (KNK) và hệ số phát thải là 3.070,3 kg CO2-tđ/ngày, 0,38 kg CO2-tđ/m3 tại Nhà máy giấy Bãi Bằng (8.000 m3/ngày) và 7.413,6 kg CO2-tđ/ngày, 0,74 kg CO2-tđ/m3 nhà máy giấy Tân Mai (10.000 m3/ngày). Nghiên cứu đã đánh giá được một số các yếu tố ảnh hưởng như nhiệt độ, lưu lượng nước thải và nồng độ cơ chất dòng vào đến sự phát thải KNK tại nhà máy giấy Tân Mai.

Em um período de mudanças climáticas e restrições a emissões cada vez maiores, é importante focar o desenvolvimento das nações na direção de uma economia de baixo carbono. O elevado consumo de combustíveis fósseis gera danos que atingem escalas globais, regionais e locais e põem em risco o suprimento de longo prazo no planeta. O presente trabalho tem como objetivo analisar o desempenho dos principais setores industriais brasileiros considerando seus respectivos consumos energéticos e contribuições para aspectos sociais e econômicos do país. Além disso, busca-se mensurar os benefícios ambientais, no que diz respeito à emissão de CO2, resultante da alteração de energéticos nos setores industriais de menor desempenho e discutir políticas públicas que visam estimular a utilização de fontes de energia mais limpas. Para atingir o objetivo proposto, foi realizada a análise e quantificação da potencial contribuição ambiental que a alteração da matriz energética dos setores com menor desempenho em relação à sua contribuição para o desenvolvimento sustentável, pode fornecer. Para determinar o desempenho dos setores foi utilizada a Análise Envoltória de Dados (DEA). Os resultados deste estudo indicaram que o setor metalúrgico e o setor de não metálicos são os que possuem o menor desempenho, considerando as variáveis selecionadas. Já para medir as emissões de CO2 dos principais combustíveis utilizados nos setores de menor desempenho foi utilizado o método Top-Down proposto pelo IPCC. A análise indicou que, apesar do carvão vegetal ser o segundo emissor de CO2, ele pode contribuir para a redução do aquecimento global, desde que seja proveniente de mata de reflorestamento destinada para a atividade industrial. Por fim, foi realizada uma breve discussão sobre as políticas públicas voltadas a este energético. / In a period of climate change and of an increasingly restriction of emissions, it is pivotal to focus on a development by countries towards an economy revolved on low carbon dioxide levels. The high consumption of fossil fuels results in damages on a global, regional and local level threatening long-term supply in our planet. This work has as its objective to analyze the performance of the main Brazilian industrial sectors considering their energy consumption and contributions to social and economic aspects of the country. In addition, will be measure the environmental benefits, in terms of CO2 emissions, resulting from fuel substitution in the industrial sectors of lower performance and discuss public policies aimed at stimulating the use of cleaner energy sources. So as to achieve this objective, an analysis and measurement assertion of the potential environmental contribution that a change of the energy matrix, of the sectors with lower performance as regards to its contribution to sustainable development of the country, may provide was performed. Data Envelopment Analysis (DEA) was used to determine the efficiency of the sectors. The results of this study indicated that the metallurgical and nonmetallic sectors are the ones that have the lowest performance industrial in terms of sustainable. For the measurement of CO2 emissions for each major fuel used in the sectors with lower performance, the Top-Down method proposed by the IPCC was used. This analysis indicated that, although charcoal is the second fuel in sectors that emit more CO2, it can contribute to the reduction of global warming since it comes from forest reforestation destined for the activity industrial. Finally, a brief discussion about public policies on this fuel was held.

Les tourbières représentent 2 à 3% des terres émergées et stockent entre 10 et 25% du carbone des sols. Les tourbières sont soumises à des contraintes anthropiques et climatiques importantes qui posent la question de la pérennité de leur fonctionnement en puits de C et de leur stock. Une meilleure compréhension de ces écosystèmes est nécessaire pour déterminer les facteurs et les effets et interactions de ces facteurs sur les émissions de gaz à effet de serre (GES). Ce travail a consisté à suivre les émissions de GES et les facteurs contrôlant dans La tourbière de La Guette (Sologne) pour établir son bilan de C. En parallèle des expérimentations sur l’effet de l’hydrologie sur les flux ont été menées, enfin un suivi sur 4 sites a été réalisé pour étudier la variabilité à l’échelle journalière. Les résultats de ces travaux montrent que la tourbière de La Guette a fonctionné en source de C (-220 ± 33 gC m-2 an-1) et ce malgré un niveau de nappe élevé. Ils montrent également l’importance de la variabilité spatiale des flux estimés à l’échelle d’un site. Les expérimentations confirment l’importance de l’hydrologie et suggèrent à haut niveau de nappe d’eau des phénomènes liés au transport des gaz. Enfin l’étude de la variabilité journalière montre que la sensibilité de la respiration à la température peut être différente le jour et la nuit et que la synchronisation entre les températures du sol et la respiration peuvent améliorer la représentation de cette dernière. / Peatlands cover only 2 to 3% of the land area but store between 10 and 25% of the soil carbon. The outcome of the anthropic and climatic pressure on these ecosystems is uncertain regarding their functions and storage. A better understanding of these ecosystems is needed to determine the factors and their interactions on greenhouse gas (GHG) emission. This work consist in monitoring GHG emissions and controlling factors in a Sphagnum peatland to estimate its carbon balance. Experimentation on mesocosms were carried out to explore the effect of hydrology on the fluxes and a monitoring on 4 sites was made to study the daily variability. Results show that La Guette peatland was a carbon source (-220 ± 33 gC m-2 an-1) in spite of the high water table level. The importance of the spatial variability measured in the site was also demonstrate. The hydrology effect was confirmed by the mesocosms experiments and high water table level shows that gas transport might have an effect. Finally the study of the daily variability show that the temperature sensitivity of the respiration might be different between day and night and that synchronizing soil temperatures and respiration can improve the respiration representation.

The article reviews the experiences of programs to promote renewable energy in Southeast Asian countries and proposes some learned lessons that can be useful in the context of COP 20 to promote renewable energy.The article analyzes the rates and mechanisms of promotion used in countries such as India, Indonesia and Vietnam, that are led by the World Bank. These mechanisms are used as a legal basis that proposes successful tested alternatives and its usefulness is that renewable energies can be implemented within the current legal structure of international environmental law.In conclusion, it is the correct timing for the COP 20 to secure funds and international legal mechanisms that promote sustainable energy infrastructure. / El presente artículo revisa las experiencias de programas de promoción de energías renovables en países del sudeste asiático a fin de proponer algunas lecciones aprendidas que puedan ser útiles en el contexto de la Vigésima Conferencia de las Partes de la Convención Marco de las Naciones Unidas sobre el Cambio Climático (COP 20) para la promoción de las energías renovables. Asimismo, revisa las tarifas y mecanismos de promoción utilizados en India, Indonesia y Vietnam, impulsados por el Banco Mundial, como una base para proponer alternativas legales ya probadas. Su utilidad es que las energías renovables pueden ser implementadas dentro de la estructura legal actual del Derecho Ambiental Internacional, la COP 20 es el momento de asegurar fondos y mecanismos jurídicos internacionales que promueven una infraestructura energética sostenible.

Em um período de mudanças climáticas e restrições a emissões cada vez maiores, é importante focar o desenvolvimento das nações na direção de uma economia de baixo carbono. O elevado consumo de combustíveis fósseis gera danos que atingem escalas globais, regionais e locais e põem em risco o suprimento de longo prazo no planeta. O presente trabalho tem como objetivo analisar o desempenho dos principais setores industriais brasileiros considerando seus respectivos consumos energéticos e contribuições para aspectos sociais e econômicos do país. Além disso, busca-se mensurar os benefícios ambientais, no que diz respeito à emissão de CO2, resultante da alteração de energéticos nos setores industriais de menor desempenho e discutir políticas públicas que visam estimular a utilização de fontes de energia mais limpas. Para atingir o objetivo proposto, foi realizada a análise e quantificação da potencial contribuição ambiental que a alteração da matriz energética dos setores com menor desempenho em relação à sua contribuição para o desenvolvimento sustentável, pode fornecer. Para determinar o desempenho dos setores foi utilizada a Análise Envoltória de Dados (DEA). Os resultados deste estudo indicaram que o setor metalúrgico e o setor de não metálicos são os que possuem o menor desempenho, considerando as variáveis selecionadas. Já para medir as emissões de CO2 dos principais combustíveis utilizados nos setores de menor desempenho foi utilizado o método Top-Down proposto pelo IPCC. A análise indicou que, apesar do carvão vegetal ser o segundo emissor de CO2, ele pode contribuir para a redução do aquecimento global, desde que seja proveniente de mata de reflorestamento destinada para a atividade industrial. Por fim, foi realizada uma breve discussão sobre as políticas públicas voltadas a este energético. / In a period of climate change and of an increasingly restriction of emissions, it is pivotal to focus on a development by countries towards an economy revolved on low carbon dioxide levels. The high consumption of fossil fuels results in damages on a global, regional and local level threatening long-term supply in our planet. This work has as its objective to analyze the performance of the main Brazilian industrial sectors considering their energy consumption and contributions to social and economic aspects of the country. In addition, will be measure the environmental benefits, in terms of CO2 emissions, resulting from fuel substitution in the industrial sectors of lower performance and discuss public policies aimed at stimulating the use of cleaner energy sources. So as to achieve this objective, an analysis and measurement assertion of the potential environmental contribution that a change of the energy matrix, of the sectors with lower performance as regards to its contribution to sustainable development of the country, may provide was performed. Data Envelopment Analysis (DEA) was used to determine the efficiency of the sectors. The results of this study indicated that the metallurgical and nonmetallic sectors are the ones that have the lowest performance industrial in terms of sustainable. For the measurement of CO2 emissions for each major fuel used in the sectors with lower performance, the Top-Down method proposed by the IPCC was used. This analysis indicated that, although charcoal is the second fuel in sectors that emit more CO2, it can contribute to the reduction of global warming since it comes from forest reforestation destined for the activity industrial. Finally, a brief discussion about public policies on this fuel was held.

Methane (CH4) is guaranteed to affect climate change and is essential in rising temperatures. Scientists have known for over two decades that wetlands emit CH4 to such an extent that it affects our climate. Tropical trees that grow in wetlands tend to emit or act as a conduit of CH4, to the extent that it has a negative environmental impact. However, until this study, no one has examined whether wetland species growing in another environment have the same effects. Hence, this thesis aimed to collect data from wetland-adapted tropical trees in a non-wetland environment, namely the Botanical Garden in Rio de Janeiro. The results showed a difference in the sampling height of the stem, namely that a decrease in emission is seen with an increased height. All the species except one (Pseudobombax munguba) showed both assimilation and emission from the day-to-day measurements of CH4, which speaks for the trees acting both as a sink and a source of CH4. This suggests that the species are more robust than the environmental stressors in a non-wetland environment. Previous studies have found that increased CH4 emissions can be seen with different meteorological parameters. The results presented in this thesis show the opposite, that some species tend to emit less or assimilate more CH4 during days with increased rainfall, humidity, and temperature.