Public bus transportation system environmental impact projections regarding different policy scenario : A LCA study

Urban activities, such as transportation, are responsible for a large portion of energyrelated CO2 emissions. As the need for sustainable urban development increases, decision-makers embrace Life Cycle Assessment (LCA) as a reliable tool capable of generating scientifically based information on environmental impacts. However, there is still a lack of an analysis standard regarding the particularities of urban systems. Therefore, this research aims to define current and future environmental profiles, considering a case study of the public transport system in Porto Alegre, considering specificities of the urban context and different public policy scenarios through LCA. These results show that, although the transportation system management relies on the municipalities, the higher significance of environmental impacts depend on a national policy for using biodiesel in the diesel sold, which could lead to an increase of, for example, up to 9.4% of CO2 emissions from 2017 (baseline) to 2030. Finally, it is perceivable that to conduct a LCA to support decision-making in public urban services, a detailed approach is needed considering that technological variables interact with the territorial context and policy changes

Life Cycle Assessment applied to construction and demolition waste treatment : proposal of a Brazilian scenario

Important amounts of construction and demolition wastes (CDW) are currently generated in several countries. Considering the correct management of this kind of residue, and the search for its noblest use, several studies have focused on the environmental potential impacts from CDW management. Life Cycle Assessment (LCA) is often used to investigate the potential environmental impacts over the life cycle of a product, thus becoming an important tool to support decision-making. CDW recycling process produces coarse, fine and mix aggregate as outputs, characterizing a multifunctional process. But, how CDW’s LCA should be run, considering a circular and more sustainable built environment? Thus, the objective of this work is to explore the basic premises in proposing a product system for the CDW recycling process in Brazil. For this, data available in the literature on the recycling process in Brazil and in other countries support the definition of the product system. The complexity of this management option is explored, considering how the use of the recycled materials interfere in the scope, objective, unit function and other modelling choices, as well as reliability of CDW studies. Finally, the datasets provided by Ecoinvent are examined in order to promote debate on data adaptation, followed by remarks on the most appropriate choices on allocation in the CDW LCA. The cut-off system modelling associated with the new perspective on the avoided burden approach is concluded by the authors to be the most suitable for this waste recycling multifunctional processes. Understanding system models is key. When no inventory adaptation is intended, available inventory datasets are more advisable to be used when performing end of life scenarios only, once burdens differ according to countries management scenarios, as well as life cycle inventory approaches

Life cycle assessment to support public policies for the urban sustainable development : a case study of the public bus transport in Porto Alegre

Pesquisas indicam que áreas urbanas são responsáveis por 71 à 76% das emissões de CO2 relacionadas a consumos energéticos. Devido à sua grande parcela de emissões nas atividades urbanas, as estratégias para o desenvolvimento urbano sustentável geralmente visam os sistemas de transporte de passageiros. A técnica de Avaliação do Ciclo de Vida (ACV) é capaz de gerar informações com base científica, confiáveis, sobre impactos ambientais para apoiar a tomada de decisão de políticas públicas urbanas. Contudo, cidades possuem sistemas multifuncionais, dinâmicos, únicos dentro de seu contexto socioeconômico, e ainda em estudo para análise segundo a ACV. Dessa forma, a presente pesquisa busca definir o perfil ambiental do sistema coletivo de transporte público de Porto Alegre, contemplando especificidades do contexto urbano e diferentes cenários de políticas públicas através da ACV Territorial. Para tanto, primeiramente, uma revisão de literatura sobre escolhas de modelagem para ACVs aplicadas a cidades e sistemas urbanos é realizada, a fim de identificar parâmetros chave no estudo destes sistemas complexos. O estudo de caso é desenvolvido e detalhado para demonstrar o procedimento de aplicação da ferramenta na verificação de impactos ambientais gerados por diferentes variáveis que contribuem com emissões na fase de uso do ciclo de vida, sendo elas: o combustível; as características dos veículos utilizados; e a rotina de operação, que inclui as distâncias percorridas e o número de usuários do transporte coletivo. As projeções de mudança até o ano de 2030 são determinadas de acordo com políticas de diferentes níveis governamentais (nacional e municipal) que influenciam estas variáveis, bem como projeções estatísticas de operação do sistema. Os resultados indicam que o combustível é a primeira fonte de mudanças significativas na busca da mitigação dos impactos no transporte público. A influência do número de passageiros nos valores de emissões é também ressaltada, dada à função do sistema (transporte de pessoas). Verifica-se, por meio dos resultados da revisão de literatura e do estudo de caso, que os impactos ambientais de sistemas urbanos podem ser analisados em função dos seus valores totais - para geração de indicadores globais de emissões ao ano. Contudo, para discussões de mudança no planejamento dos mesmos, a análise da função é imprescindível. Sendo assim, sugere-se que as deliberações sobre o assunto devem considerar ambas as análises. Da mesma forma, verifica-se que resultados de ACV para políticas públicas de longo prazo são melhores representados de maneira dinâmica, demonstrando mudanças ao longo do tempo, para auxiliar os tomadores de decisão no monitoramento e manutenção do planejamento segundo os objetivos de redução de impacto. Além disso, a identificação de diferentes níveis organizacionais envolvidos no ciclo de vida de sistemas urbanos é chave para que os governantes possam entender a extensão das mudanças ambientais causadas pela tomada de decisão no âmbito público.Researches indicate that urban areas are responsible for 71 to 76% of CO2 emissions related to energy consumption. Due to their large share of emissions in urban activities, strategies for sustainable urban development generally target passenger transportation systems. The standardized Life Cycle Assessment (LCA) tool is capable of generating scientifically based and reliable information on environmental impacts to support decision-making in urban public policies. However, cities have multifunctional and dynamic systems, unique within their socio-economic context, and still under study according to the LCA perspective. Thus, this research seeks to identify the environmental profile of the public bus transportation system in Porto Alegre, considering specificities of the urban context and different public policy scenarios through the Territorial LCA. For that, first, a literature review on modelling choices for LCAs applied to cities and urban systems is carried out, to identify key parameters in the study of these complex systems. The case study is developed and detailed to demonstrate the procedure for applying the tool in the verification of environmental impacts generated by different variables that contribute to emissions in the use phase of the life cycle, namely: fuel; the characteristics of the vehicles used; and the operation routine, which includes the mileage and the number of users of public bus transportation. The yearly changing projections -up to the year 2030- are determined according to policies of different government levels (national and municipal) that influence these variables, as well as statistical projections of the system's operation routine. The results indicate that fuel is the first source of significant changes in the quest to mitigate impacts on public bus transportation. The influence of the number of passengers on the emission values is also highlighted, given the function of the system (transportation of people). It is verified, through the results of both literature review and case study, that the environmental impacts of urban systems can be assessed according to their total values - to generate global emissions indicators per year. However, for discussions of changes in their planning, analysis of the function is essential. Therefore, it is suggested that the deliberations on the subject should consider both analyzes. Likewise, it appears that LCA results for long-term public policies are better represented dynamically, demonstrating changes over time, to assist decision-makers in monitoring and managing plans for impact reduction. Besides, the identification of different organizational levels involved in the life cycle of urban systems is key for government officials to understand the extent of environmental changes caused by urban public policies

Life cycle assessment to support public policies for the urban sustainable development : a case study of the public bus transport in Porto Alegre

Pesquisas indicam que áreas urbanas são responsáveis por 71 à 76% das emissões de CO2 relacionadas a consumos energéticos. Devido à sua grande parcela de emissões nas atividades urbanas, as estratégias para o desenvolvimento urbano sustentável geralmente visam os sistemas de transporte de passageiros. A técnica de Avaliação do Ciclo de Vida (ACV) é capaz de gerar informações com base científica, confiáveis, sobre impactos ambientais para apoiar a tomada de decisão de políticas públicas urbanas. Contudo, cidades possuem sistemas multifuncionais, dinâmicos, únicos dentro de seu contexto socioeconômico, e ainda em estudo para análise segundo a ACV. Dessa forma, a presente pesquisa busca definir o perfil ambiental do sistema coletivo de transporte público de Porto Alegre, contemplando especificidades do contexto urbano e diferentes cenários de políticas públicas através da ACV Territorial. Para tanto, primeiramente, uma revisão de literatura sobre escolhas de modelagem para ACVs aplicadas a cidades e sistemas urbanos é realizada, a fim de identificar parâmetros chave no estudo destes sistemas complexos. O estudo de caso é desenvolvido e detalhado para demonstrar o procedimento de aplicação da ferramenta na verificação de impactos ambientais gerados por diferentes variáveis que contribuem com emissões na fase de uso do ciclo de vida, sendo elas: o combustível; as características dos veículos utilizados; e a rotina de operação, que inclui as distâncias percorridas e o número de usuários do transporte coletivo. As projeções de mudança até o ano de 2030 são determinadas de acordo com políticas de diferentes níveis governamentais (nacional e municipal) que influenciam estas variáveis, bem como projeções estatísticas de operação do sistema. Os resultados indicam que o combustível é a primeira fonte de mudanças significativas na busca da mitigação dos impactos no transporte público. A influência do número de passageiros nos valores de emissões é também ressaltada, dada à função do sistema (transporte de pessoas). Verifica-se, por meio dos resultados da revisão de literatura e do estudo de caso, que os impactos ambientais de sistemas urbanos podem ser analisados em função dos seus valores totais - para geração de indicadores globais de emissões ao ano. Contudo, para discussões de mudança no planejamento dos mesmos, a análise da função é imprescindível. Sendo assim, sugere-se que as deliberações sobre o assunto devem considerar ambas as análises. Da mesma forma, verifica-se que resultados de ACV para políticas públicas de longo prazo são melhores representados de maneira dinâmica, demonstrando mudanças ao longo do tempo, para auxiliar os tomadores de decisão no monitoramento e manutenção do planejamento segundo os objetivos de redução de impacto. Além disso, a identificação de diferentes níveis organizacionais envolvidos no ciclo de vida de sistemas urbanos é chave para que os governantes possam entender a extensão das mudanças ambientais causadas pela tomada de decisão no âmbito público.Researches indicate that urban areas are responsible for 71 to 76% of CO2 emissions related to energy consumption. Due to their large share of emissions in urban activities, strategies for sustainable urban development generally target passenger transportation systems. The standardized Life Cycle Assessment (LCA) tool is capable of generating scientifically based and reliable information on environmental impacts to support decision-making in urban public policies. However, cities have multifunctional and dynamic systems, unique within their socio-economic context, and still under study according to the LCA perspective. Thus, this research seeks to identify the environmental profile of the public bus transportation system in Porto Alegre, considering specificities of the urban context and different public policy scenarios through the Territorial LCA. For that, first, a literature review on modelling choices for LCAs applied to cities and urban systems is carried out, to identify key parameters in the study of these complex systems. The case study is developed and detailed to demonstrate the procedure for applying the tool in the verification of environmental impacts generated by different variables that contribute to emissions in the use phase of the life cycle, namely: fuel; the characteristics of the vehicles used; and the operation routine, which includes the mileage and the number of users of public bus transportation. The yearly changing projections -up to the year 2030- are determined according to policies of different government levels (national and municipal) that influence these variables, as well as statistical projections of the system's operation routine. The results indicate that fuel is the first source of significant changes in the quest to mitigate impacts on public bus transportation. The influence of the number of passengers on the emission values is also highlighted, given the function of the system (transportation of people). It is verified, through the results of both literature review and case study, that the environmental impacts of urban systems can be assessed according to their total values - to generate global emissions indicators per year. However, for discussions of changes in their planning, analysis of the function is essential. Therefore, it is suggested that the deliberations on the subject should consider both analyzes. Likewise, it appears that LCA results for long-term public policies are better represented dynamically, demonstrating changes over time, to assist decision-makers in monitoring and managing plans for impact reduction. Besides, the identification of different organizational levels involved in the life cycle of urban systems is key for government officials to understand the extent of environmental changes caused by urban public policies

A spatiotemporally differentiated product system modelling framework for consequential life cycle assessment

Consequential life cycle assessment (CLCA) applied to systems under continuous evolution, such as cities, usually disregard interactions among local components, how policy decisions influence them, and the value of spatial data. As a result, local environmental impacts might not be well-considered. This paper investigates how a spatially explicit system dynamics (SD) modelling approach can overcome such limitation, contributing to the advancement of CLCA. First, a novel CLCA conceptual framework is presented combining consequential life cycle inventories, SD principles and the use of spatially explicit data. Second, its innovative value is demonstrated through a proof-of-concept SD-CLCA model. This model evaluates the environmental impacts of changes in electricity supply-demand in the market due to an increasing adoption of solar photovoltaic panels (SPV) in residential buildings. It allows traceability of both system changes and their environmental consequences. For demonstration purposes, the SD-CLCA model is applied to Lisbon municipality and the broader electricity market of Portugal. Results showcase how SD-CLCA models could provide a closer representation of the real effects of predicted changes in the electricity market due to different SPV adoption scenarios. They also illustrate that changes in gross domestic product, population and precipitation provide a diversified set of impact scores. As a methodological advancement, and to the net of a few shortcomings, the proposed SD-CLCA model is able to capture the complexity of cause-effect dynamics determining environmental impacts, which currently represents a research gap in LCA

Life Cycle Assessment applied to construction and demolition waste treatment : proposal of a Brazilian scenario

Important amounts of construction and demolition wastes (CDW) are currently generated in several countries. Considering the correct management of this kind of residue, and the search for its noblest use, several studies have focused on the environmental potential impacts from CDW management. Life Cycle Assessment (LCA) is often used to investigate the potential environmental impacts over the life cycle of a product, thus becoming an important tool to support decision-making. CDW recycling process produces coarse, fine and mix aggregate as outputs, characterizing a multifunctional process. But, how CDW’s LCA should be run, considering a circular and more sustainable built environment? Thus, the objective of this work is to explore the basic premises in proposing a product system for the CDW recycling process in Brazil. For this, data available in the literature on the recycling process in Brazil and in other countries support the definition of the product system. The complexity of this management option is explored, considering how the use of the recycled materials interfere in the scope, objective, unit function and other modelling choices, as well as reliability of CDW studies. Finally, the datasets provided by Ecoinvent are examined in order to promote debate on data adaptation, followed by remarks on the most appropriate choices on allocation in the CDW LCA. The cut-off system modelling associated with the new perspective on the avoided burden approach is concluded by the authors to be the most suitable for this waste recycling multifunctional processes. Understanding system models is key. When no inventory adaptation is intended, available inventory datasets are more advisable to be used when performing end of life scenarios only, once burdens differ according to countries management scenarios, as well as life cycle inventory approaches