A questão energética é um dos principais desafios do século XXI. Por outro lado, os aspectos geopolíticos e ambientais, são fontes de preocupação para o modelo econômico atual. O Brasil é um país que apresenta vantagens em relação ao mundo em termos de utilização de fontes renováveis de energia. Desde 2007 os produtos da cana-de-açúcar assumiram o primeiro lugar na oferta de energia renovável. A análise de energia é necessária para o gerenciamento de recursos naturais limitados, para abastecer, com as mais diversas alternativas de biomassa, uma população mundial em constante crescimento. Essa análise identifica as práticas de produção e quantifica sua eficiência sob o ponto de vista energético, determinando a energia incorporada nas etapas do processo de produção. Estudos de energia incorporada em máquinas agrícolas são escassos. A participação do setor sucroalcooleiro na matriz energética do Brasil, fornecendo energia renovável a partir da biomassa tem aumentado. Devido à energia consumida no processo, ser produzida a partir dos seus próprios resíduos, avaliar as formas pelas quais a energia é demandada é vital para se determinar a viabilidade energética dessa fonte. Esse estudo visa determinar a energia incorporada em colhedora autopropelida de cana-de-açúcar. Foram avaliadas duas colhedoras, denominadas Máquina 1 equipada com rodas e pneus e Máquina 2 equipada com esteiras metálicas, fabricadas por uma companhia localizada na região de Piracicaba, Estado de São Paulo, Brasil. Para cada colhedora foi contabilizado o consumo dos insumos (diretos e indiretos) utilizados na fase de montagem, bem como, o consumo dos insumos utilizados na fase de manutenção e reparo. Os dados de consumo dos insumos foram processados apresentando os fluxos de materiais utilizados, os quais foram multiplicados pelo seu índice de energia incorporada, resultando na energia incorporada nos insumos. Os resultados demonstram que a Máquina 2 apresentou maior energia incorporada (204,3 MJ kg-1) do que a Máquina 1 (202,6 MJ kg-1) durante o ciclo de vida útil, isso foi influenciado diretamente pelo rodante utilizado pela máquina 2. A energia incorporada na mão-de-obra requerida para desempenhar a atividade de montagem foi baixa comparada com as outras categorias de energia. O aço carbono foi o insumo que obteve a maior representatividade de consumo. A energia incorporada indiretamente nos insumos foi baixa comparada com as verificadas nos demais insumos. Em termos de consumo de energia incorporada, a Máquina 1 é melhor que a Máquina 2, porém esta última propicia menores danos ao canavial, fato esse que pode compensar sua maior demanda energética ao longo de seu ciclo de vida. / The energy subject is one of the main challenges of 21st century. The geopolitical and environment aspects, they are concern sources to the current economic model. Brazil presents advantages in comparison to the world due to the use of renewable energy. Since 2007, products from the sugarcane have assumed the first place as a renewable source in the Brazilian energy matrix. Energy analysis is necessary in order to monitor of scarce natural resources, to supply, with the most several biomass alternatives, a world population in constant growth. This analysis identifies the production practices and quantifies their efficiency in the energy point of view, determining the embodied energy in the steps of the production process. Studies of embodied energy in agricultural machinery are rare. The participation of the sugarcane sector in the Brazilian energetic matrix has increased. Due to the energy consumed in their processes it is interesting to quantify these input flows in order to monitor the energy feasibility of this source. This study aimed to determine the embodied energy in the self-propelled sugarcane harvester. Two models were evaluated, so called: Machine 1 equipped with wheels and tires; and Machine 2 equipped with metallic tracks, manufactured by a company located at Piracicaba region, State of São Paulo, Brazil. For every harvester, the consumption of the input (direct and indirect) used in the assembly phase, was accounted, and also the consumption of the input used in the maintenance and repair phase. The consumption data of the inputs were processed presenting the materials flows used, which they were multiplied by their embodied energy indices, resulting in the embodied energy required by the production system. The results show that Machine 2 presented higher embodied energy (204.3 MJ kg-1) than the Machine 1 (202.6 MJ kg-1) during their life cycle and this was influenced directly by the rolling used by the Machine 2. The embodied energy by demanded by labor in the assembly activity was low compared with the other categories of energy. The steel carbon represented the input with the highest consumption. The incorporated energy indirectly in the input was low compared with the verified on the other inputs. In terms of embodied energy consumption, Machine 1 is better than Machine 2, although the latter may cause less damage to the sugarcane rattons which can compensate the higher energy demand in its life cycle.

No presente trabalho se analisou o consumo energético de uma moradia social, para isto se calculou a energia incorporada nos materiais construtivos utilizados no projeto da moradia analisada e o consumo energético provocado pelo comportamento térmico da envolvente térmica da edificação estudando como a mudança dos materiais construtivos como: telhados e paredes modificam o valor da energia incorporada e o consumo de energia elétrica pelo comportamento térmico, uma vez que se considera possível que o consumo energético por motivos térmico seja maior que a energia incorporada. Para o calculo da energia incorporadados materiais construtivos que compõem a envolvente, foram utilizados coeficientes de energia incorporada propostos por Tavares, (2006), Graf; Tavares, (2010), Lobo, (2010). A pesquisa foi enfocada ao setor habitacional por ser um dos setores que apresentam maior consumo de energia, enfocando-se especificamente à moradia social. A metodologia para avaliar o consumo energético da edificação no período de análise, se divide em quatros etapas: 1) Quantificação de materiais da envolvente 2) Cálculo de energia incorporada 3) Cálculo de gasto energético nos períodos de 1 e 40 anos realizado por meio de simulações no software Energy Plus 4) Cálculo dos coeficientes de correlação das variáveis.Tomaram-se as cidades de São Carlos, SP e Belém, PA, como exemplos de análise. A primeira cidade participa com 11% no rubro de condicionamento ambiental no setor residencial e segunda participa com 40%. Os resultados foram trabalhados e analisados com gráficos de Excel, para a posterior análise e conclusão. Identificou-se um coeficiente de correlação que indica uma forte correlação entres as variáveis analisadas no presente. O que indica que existe uma relação entre a quantidade de energia incorporada nos materiais e no consumo energético operacional pelo comportamento térmico destes. / In this study were analyzed the energy consumption of a housing, for it is calculated the embodied energy of construction materials, and energy consumption caused by the thermal behavior of the building envelope. It was change the building materials in the building, modifying the value of embodied energy and electricity consumption, since it is possible that the energy consumption of thermal behavior can be higher than the energy embodied. To calculate the embodied energy, were used a embodied energy coefficients proposed by Tavares, (2006), Graf; Tavares, (2010)Lobo, (2010).(TAVARES, SERGIO FERNANDO, 2006). This research is focus to residential sector as one of the sectors with higher energy consumption, focusing specifically on social housing. The methodology to evaluate energy consumption in the building during the period of analysis is divided into three steps: 1) Quantification of the materials 2) Calculate the embodied energy 3) Calculate the consumption of energy in the period of 40 years, made by simulations in Energy Plus software 4) Calculate the correlation ship between the variables analyzed. It follows the cities of São Carlos, SP and Belem, PA as examples of analysis; the first city participates with 11% in the energy consumption used in environmental conditioning in the residential sector and the second city participates with 40%. Changes were made in the materials of walls and roofs, trying to identify the differences of embodied energy and electricity consumption. The data obtained were worked in Excel spread sheets for further analysis and conclusion of the data. It was identified a strongly correlation coefficient between the analyzed variables.

A questão energética é um dos principais desafios do século XXI. Por outro lado, os aspectos geopolíticos e ambientais, são fontes de preocupação para o modelo econômico atual. O Brasil é um país que apresenta vantagens em relação ao mundo em termos de utilização de fontes renováveis de energia. Desde 2007 os produtos da cana-de-açúcar assumiram o primeiro lugar na oferta de energia renovável. A análise de energia é necessária para o gerenciamento de recursos naturais limitados, para abastecer, com as mais diversas alternativas de biomassa, uma população mundial em constante crescimento. Essa análise identifica as práticas de produção e quantifica sua eficiência sob o ponto de vista energético, determinando a energia incorporada nas etapas do processo de produção. Estudos de energia incorporada em máquinas agrícolas são escassos. A participação do setor sucroalcooleiro na matriz energética do Brasil, fornecendo energia renovável a partir da biomassa tem aumentado. Devido à energia consumida no processo, ser produzida a partir dos seus próprios resíduos, avaliar as formas pelas quais a energia é demandada é vital para se determinar a viabilidade energética dessa fonte. Esse estudo visa determinar a energia incorporada em colhedora autopropelida de cana-de-açúcar. Foram avaliadas duas colhedoras, denominadas Máquina 1 equipada com rodas e pneus e Máquina 2 equipada com esteiras metálicas, fabricadas por uma companhia localizada na região de Piracicaba, Estado de São Paulo, Brasil. Para cada colhedora foi contabilizado o consumo dos insumos (diretos e indiretos) utilizados na fase de montagem, bem como, o consumo dos insumos utilizados na fase de manutenção e reparo. Os dados de consumo dos insumos foram processados apresentando os fluxos de materiais utilizados, os quais foram multiplicados pelo seu índice de energia incorporada, resultando na energia incorporada nos insumos. Os resultados demonstram que a Máquina 2 apresentou maior energia incorporada (204,3 MJ kg-1) do que a Máquina 1 (202,6 MJ kg-1) durante o ciclo de vida útil, isso foi influenciado diretamente pelo rodante utilizado pela máquina 2. A energia incorporada na mão-de-obra requerida para desempenhar a atividade de montagem foi baixa comparada com as outras categorias de energia. O aço carbono foi o insumo que obteve a maior representatividade de consumo. A energia incorporada indiretamente nos insumos foi baixa comparada com as verificadas nos demais insumos. Em termos de consumo de energia incorporada, a Máquina 1 é melhor que a Máquina 2, porém esta última propicia menores danos ao canavial, fato esse que pode compensar sua maior demanda energética ao longo de seu ciclo de vida. / The energy subject is one of the main challenges of 21st century. The geopolitical and environment aspects, they are concern sources to the current economic model. Brazil presents advantages in comparison to the world due to the use of renewable energy. Since 2007, products from the sugarcane have assumed the first place as a renewable source in the Brazilian energy matrix. Energy analysis is necessary in order to monitor of scarce natural resources, to supply, with the most several biomass alternatives, a world population in constant growth. This analysis identifies the production practices and quantifies their efficiency in the energy point of view, determining the embodied energy in the steps of the production process. Studies of embodied energy in agricultural machinery are rare. The participation of the sugarcane sector in the Brazilian energetic matrix has increased. Due to the energy consumed in their processes it is interesting to quantify these input flows in order to monitor the energy feasibility of this source. This study aimed to determine the embodied energy in the self-propelled sugarcane harvester. Two models were evaluated, so called: Machine 1 equipped with wheels and tires; and Machine 2 equipped with metallic tracks, manufactured by a company located at Piracicaba region, State of São Paulo, Brazil. For every harvester, the consumption of the input (direct and indirect) used in the assembly phase, was accounted, and also the consumption of the input used in the maintenance and repair phase. The consumption data of the inputs were processed presenting the materials flows used, which they were multiplied by their embodied energy indices, resulting in the embodied energy required by the production system. The results show that Machine 2 presented higher embodied energy (204.3 MJ kg-1) than the Machine 1 (202.6 MJ kg-1) during their life cycle and this was influenced directly by the rolling used by the Machine 2. The embodied energy by demanded by labor in the assembly activity was low compared with the other categories of energy. The steel carbon represented the input with the highest consumption. The incorporated energy indirectly in the input was low compared with the verified on the other inputs. In terms of embodied energy consumption, Machine 1 is better than Machine 2, although the latter may cause less damage to the sugarcane rattons which can compensate the higher energy demand in its life cycle.

<p>The focus in environmental management has during the last decades in many cases shifted to include all the phases in a product’s (or a service’s) life – the life-cycle perspective. The transport system has a large environmental pressure on the environment. Train traffic is habitually regarded as an environmentally preferable mean of transport, mainly depending on that trains often are driven by electricity. This view is also true when the operation phase alone is considered; at least if the electricity derives from renewable sources. In a life-cycle perspective the advantages of this mean of transport get less apparent. The extraction of the raw materials requires plenty of energy, energy which often is produced by fossil fuels. A dominating part of the material-related energy requirements in the railway infrastructure can be referred to a few materials. The main part of these materials can be found in a few products; rails, railway ties, ballast materials, cables and the contact wire system. It is here that the effort to reduce the environmental impact of the railway infrastructure should lie to become most efficient. The aim of the thesis is to investigate how the environmental pressure is affected by the service lives, i.e. the technical durability as well as the durability in practise, of the most energy-intense railway products, as well as reuse of them. The objective is to map estimated service lives and reuse in order to create scenarios representing the present state of how the products are used and reused in Sweden. The scenarios are used in order to analyse the importance of focusing on service lives and reuse when reducing environmental pressure. The objective is also to find out which possibilities and hindrances there are to increase the service lives and the reuse of the products.</p><p>To investigate the environmental pressure of the railway infrastructure, embodied energy is used as indicator. Embodied energy represents the energy needed to produce a product, from extracting the materials to the production phase. The present state concerning service lives and reuse of the studied products are mapped through interviews with employees at Banverket and at VTI. The empirical material is analysed and scenarios are created in order to evaluate the environmental importance of service lives and reuse. Organizational issues concerning service lives and reuse are also investigated.</p><p>The present state service lives varies between 25 and 100 years for the realistic scenarios for all the products. The estimated service lives varies between 25 and 100 years for the new technology scenarios. When it comes to the best-case scenarios the estimated service lives varies between 60 and 120 years, depending on railway product. The only products reused today are rails and railway ties. There are considerable improvements to be made by increasing service lives, and this pertains to all the studied products. The reductions in embodied energy per year go up to 75 % if the New-Technology Scenario is applied and to 33 % if the Realistic Scenarios are applied. If the Low Realistic Scenarios are applied the reductions goes up to 50 %. A great improvement potential exist for all the products if the New-Technology Scenarios are applied. The products where the main improvement potential when it comes to the Realistic and the Low Realistic Scenarios exist are the macadam-ballast, the cables, the rails and the railway ties. If the New-Technology Scenarios are applied for all the products the total improvement span is as much as 69 % altogether. If the Low Realistic Scenario instead is applied, the improvement span is calculated to 38-39 % (depending on the exchange level of macadam-ballast). If the Realistic Scenario is applied, the improvement span is calculated to 23 % and if the Best-Case Scenario is applied the span is calculated to 7 %, depending on that the most energy efficient strategy is to reuse the products possible to reuse. The main part of this improvement potential derives from the rails and the railway ties.</p><p>In reducing the environmental pressure it is important to make use of the products as much as possible, i.e. to reuse them and use them as long as possible. If rails and railway ties are reused and made use of during their entire service life, all energy invested in the products is made use of. The most environmental sound alternative is to reuse the products which are reusable and to use these products as long as they last. This gives a need for embodied energy of 16 GJ/yr and km for the railway ties and 38 GJ/yr for the rails on the mainline track. The energy allocated to the tracks where the products are reused is calculated to 3 GJ/yr and km for the railway ties and to 7 GJ/yr and km for the rails. Actions of maintenance prolong the durability of the products, e.g. by increasing the stability in the embankment and hence reduce the wearing. The administration of the used material is the main problem in order to create a well-functioning reuse of railway articles. This includes transports, storage and documentation of products. Tradition and routines also stand in the way of creating a sustainable reuse of these products.</p>

The focus in environmental management has during the last decades in many cases shifted to include all the phases in a product’s (or a service’s) life – the life-cycle perspective. The transport system has a large environmental pressure on the environment. Train traffic is habitually regarded as an environmentally preferable mean of transport, mainly depending on that trains often are driven by electricity. This view is also true when the operation phase alone is considered; at least if the electricity derives from renewable sources. In a life-cycle perspective the advantages of this mean of transport get less apparent. The extraction of the raw materials requires plenty of energy, energy which often is produced by fossil fuels. A dominating part of the material-related energy requirements in the railway infrastructure can be referred to a few materials. The main part of these materials can be found in a few products; rails, railway ties, ballast materials, cables and the contact wire system. It is here that the effort to reduce the environmental impact of the railway infrastructure should lie to become most efficient. The aim of the thesis is to investigate how the environmental pressure is affected by the service lives, i.e. the technical durability as well as the durability in practise, of the most energy-intense railway products, as well as reuse of them. The objective is to map estimated service lives and reuse in order to create scenarios representing the present state of how the products are used and reused in Sweden. The scenarios are used in order to analyse the importance of focusing on service lives and reuse when reducing environmental pressure. The objective is also to find out which possibilities and hindrances there are to increase the service lives and the reuse of the products. To investigate the environmental pressure of the railway infrastructure, embodied energy is used as indicator. Embodied energy represents the energy needed to produce a product, from extracting the materials to the production phase. The present state concerning service lives and reuse of the studied products are mapped through interviews with employees at Banverket and at VTI. The empirical material is analysed and scenarios are created in order to evaluate the environmental importance of service lives and reuse. Organizational issues concerning service lives and reuse are also investigated. The present state service lives varies between 25 and 100 years for the realistic scenarios for all the products. The estimated service lives varies between 25 and 100 years for the new technology scenarios. When it comes to the best-case scenarios the estimated service lives varies between 60 and 120 years, depending on railway product. The only products reused today are rails and railway ties. There are considerable improvements to be made by increasing service lives, and this pertains to all the studied products. The reductions in embodied energy per year go up to 75 % if the New-Technology Scenario is applied and to 33 % if the Realistic Scenarios are applied. If the Low Realistic Scenarios are applied the reductions goes up to 50 %. A great improvement potential exist for all the products if the New-Technology Scenarios are applied. The products where the main improvement potential when it comes to the Realistic and the Low Realistic Scenarios exist are the macadam-ballast, the cables, the rails and the railway ties. If the New-Technology Scenarios are applied for all the products the total improvement span is as much as 69 % altogether. If the Low Realistic Scenario instead is applied, the improvement span is calculated to 38-39 % (depending on the exchange level of macadam-ballast). If the Realistic Scenario is applied, the improvement span is calculated to 23 % and if the Best-Case Scenario is applied the span is calculated to 7 %, depending on that the most energy efficient strategy is to reuse the products possible to reuse. The main part of this improvement potential derives from the rails and the railway ties. In reducing the environmental pressure it is important to make use of the products as much as possible, i.e. to reuse them and use them as long as possible. If rails and railway ties are reused and made use of during their entire service life, all energy invested in the products is made use of. The most environmental sound alternative is to reuse the products which are reusable and to use these products as long as they last. This gives a need for embodied energy of 16 GJ/yr and km for the railway ties and 38 GJ/yr for the rails on the mainline track. The energy allocated to the tracks where the products are reused is calculated to 3 GJ/yr and km for the railway ties and to 7 GJ/yr and km for the rails. Actions of maintenance prolong the durability of the products, e.g. by increasing the stability in the embankment and hence reduce the wearing. The administration of the used material is the main problem in order to create a well-functioning reuse of railway articles. This includes transports, storage and documentation of products. Tradition and routines also stand in the way of creating a sustainable reuse of these products.

The residential sector is recognized as a major energy consumer and thus a significant contributor to climate change. Rather than focus only on current energy consumption and the associated emissions, there is a need to broaden sustainability research to include full life cycle contributions and impacts. This thesis looks at houses from the perspective of the Ecological Footprint (EF), a well-known sustainability indicator. The research objective is to integrate EF and Life Cycle Analysis (LCA) measures to provide an enhanced tool to measure the sustainability implications of residential energy retrofit decisions. Exemplifying single-detached houses of the early 20th century, the century-old REEP House (downtown Kitchener, Canada), together with its high performance energy retrofits, is examined in detail. This research combines material, energy and carbon emission studies. Its scope covers the life cycle of the house, including the direct and indirect consumption of material and energy, and concomitant carbon emissions during its stages of material extraction, transportation, construction, operation, and demolition. The results show that the REEP House had a significant embodied impact on the environment when it was built and high operating energy and EF requirements because of the low levels of insulation. Even though the renovations to improve energy efficiency by 80% introduce additional embodied environmental impacts, they are environmentally sound activities because the environmental payback period is less than two years.

The residential sector is recognized as a major energy consumer and thus a significant contributor to climate change. Rather than focus only on current energy consumption and the associated emissions, there is a need to broaden sustainability research to include full life cycle contributions and impacts. This thesis looks at houses from the perspective of the Ecological Footprint (EF), a well-known sustainability indicator. The research objective is to integrate EF and Life Cycle Analysis (LCA) measures to provide an enhanced tool to measure the sustainability implications of residential energy retrofit decisions. Exemplifying single-detached houses of the early 20th century, the century-old REEP House (downtown Kitchener, Canada), together with its high performance energy retrofits, is examined in detail. This research combines material, energy and carbon emission studies. Its scope covers the life cycle of the house, including the direct and indirect consumption of material and energy, and concomitant carbon emissions during its stages of material extraction, transportation, construction, operation, and demolition. The results show that the REEP House had a significant embodied impact on the environment when it was built and high operating energy and EF requirements because of the low levels of insulation. Even though the renovations to improve energy efficiency by 80% introduce additional embodied environmental impacts, they are environmentally sound activities because the environmental payback period is less than two years.

No cenário mundial atual, em que é observado o aumento da população, da demanda por alimentos e da utilização de energia, também é observada a busca por fontes de energia alternativas às fósseis, diminuindo a dependência e risco econômico e ambiental oriundo de seu uso exclusivo. A análise de fluxos de energia possibilita uma avaliação da sustentabilidade de sistemas de produção agrícola, que visa o uso eficiente de insumos em termos energéticos. Essas análises também permitem identificar culturas como fonte de bioenergia, além de poderem ser utilizadas como complemento às análises econômicas, na busca por sistemas de produção mais eficientes. Esse estudo teve como objetivo apresentar uma análise do uso de insumos e energia, bem como a sua eficiência, em sistemas de produção de plantas forrageiras, tradicionalmente utilizadas para alimentação animal, na região dos Campos Gerais, Paraná. Foram determinados o fluxo de materiais (FM), demanda (EE) e disponibilização de energia (ES), balanço energético (BE), lucratividade energética (EROI) e energia incorporada (EI) da biomassa foram aplicados nesses sistemas. O FM determinou o consumo de insumos por área, e serviu de base para o cálculo da EE dos sistemas. Com características das culturas, calculou-se a ES, e com base nesses parâmetros, calculou-se os indicadores BE, EROI e EI. Com base nos resultados, concluiu-se que as culturas que se apresentaram mais eficientes do ponto de vista energético foram as gramíneas perenes, cultivares de P. maximum e Tifton 85, e as gramíneas anuais, milho e sorgo, pois apresentaram os melhores valores de indicadores da eficiência energética (ES, BE, EROI e EI), o que justificaria uma posterior investigação detalhada no uso energético dessas culturas. As culturas da aveia, azevém, cevada e milheto apresentaram os valores menos favoráveis no enfoque energético, portanto não adequadas à finalidade energética em relação às demais culturas estudadas. A operação que apresentou maior demanda de energia foi a distribuição de fertilizantes, devido aos insumos aplicados (mais que 47% da demanda total de todas as operações realizadas nas culturas). Os insumos que apresentaram maiores demandas de energia (mais de 57% do total) nos sistemas foram os fertilizantes, seguidos do diesel. Destacou-se o uso do fertilizante nitrogenado que representou mais de 50% da demanda total de energia em todos os sistemas de produção. O EROI para as cultivares de P. maximum, Tifton 85, milho, sorgo, milheto, azevém, cevada e aveia, foram: 14,2; 13,7; 10,1; 8,9; 7,2; 5,0; 4,6 e 3,8, respectivamente. / In the current world scenario, in which is observed the increase in population, demand for food and energy use, it is also observed the search for alternative energy sources to fossil fuels, decreasing dependence and environmental and economic risk arising from your use. Energy flows analysis enables an assessment of the sustainability of agricultural production systems, aiming the efficient use of inputs in energy terms. These analysis can also identify crops as a bioenergy source, and can be used as a complement to economic analysis, in the search for more efficient production systems. This study aimed to present an analysis of the use of inputs and energy, as well as its efficiency, in forage production systems, traditionally used for food, in the region of Campos Gerais, Paraná. Material flow (MF), demand (ED) and energy availability (EA), energy balance (EB), energy profitability (EROI) and embodied energy (EE) of biomass were calculated for all the systems. MF determined the inputs use per area, and was basis for the ED determination. With crop characteristics, EA was obtained, and based on these parameters, the indicators EB, EROI and EE were determined. Based on the results, it was concluded that the crops that were more efficient in energy terms were the perennial grasses, P. maximum cultivars and Tifton 85, and the annual grasses, maize and sorghum, since they presented the best values in the used energy indicators (EA, EB, EE and EROI), which would justify a further detailed investigation concerning the energy use of these crops. Oats, rye, barley and millet showed less favorable values, therefore not suitable for energy purposes in relation to other studied crops. The mechanized operation with the highest energy demand was the fertilizer distribution due to applied inputs (more than 47% of the total energy demand of all operations performed in cultures). The inputs that presented higher energy demand (more than 57% of the total) were fertilizers, followed by diesel, in all production systems. The use of nitrogen fertilizer is emphasized, since it represented over 50% of total energy demand in all production systems. The EROI for the cultivars of P. maximum, Tifton 85, maize, sorghum, millet, rye, barley and oats, were 14.2, 13.7, 10.1, 8.9, 7.2, 5.0, 4.6 and 3.8 , respectively.

No presente trabalho se analisou o consumo energético de uma moradia social, para isto se calculou a energia incorporada nos materiais construtivos utilizados no projeto da moradia analisada e o consumo energético provocado pelo comportamento térmico da envolvente térmica da edificação estudando como a mudança dos materiais construtivos como: telhados e paredes modificam o valor da energia incorporada e o consumo de energia elétrica pelo comportamento térmico, uma vez que se considera possível que o consumo energético por motivos térmico seja maior que a energia incorporada. Para o calculo da energia incorporadados materiais construtivos que compõem a envolvente, foram utilizados coeficientes de energia incorporada propostos por Tavares, (2006), Graf; Tavares, (2010), Lobo, (2010). A pesquisa foi enfocada ao setor habitacional por ser um dos setores que apresentam maior consumo de energia, enfocando-se especificamente à moradia social. A metodologia para avaliar o consumo energético da edificação no período de análise, se divide em quatros etapas: 1) Quantificação de materiais da envolvente 2) Cálculo de energia incorporada 3) Cálculo de gasto energético nos períodos de 1 e 40 anos realizado por meio de simulações no software Energy Plus 4) Cálculo dos coeficientes de correlação das variáveis.Tomaram-se as cidades de São Carlos, SP e Belém, PA, como exemplos de análise. A primeira cidade participa com 11% no rubro de condicionamento ambiental no setor residencial e segunda participa com 40%. Os resultados foram trabalhados e analisados com gráficos de Excel, para a posterior análise e conclusão. Identificou-se um coeficiente de correlação que indica uma forte correlação entres as variáveis analisadas no presente. O que indica que existe uma relação entre a quantidade de energia incorporada nos materiais e no consumo energético operacional pelo comportamento térmico destes. / In this study were analyzed the energy consumption of a housing, for it is calculated the embodied energy of construction materials, and energy consumption caused by the thermal behavior of the building envelope. It was change the building materials in the building, modifying the value of embodied energy and electricity consumption, since it is possible that the energy consumption of thermal behavior can be higher than the energy embodied. To calculate the embodied energy, were used a embodied energy coefficients proposed by Tavares, (2006), Graf; Tavares, (2010)Lobo, (2010).(TAVARES, SERGIO FERNANDO, 2006). This research is focus to residential sector as one of the sectors with higher energy consumption, focusing specifically on social housing. The methodology to evaluate energy consumption in the building during the period of analysis is divided into three steps: 1) Quantification of the materials 2) Calculate the embodied energy 3) Calculate the consumption of energy in the period of 40 years, made by simulations in Energy Plus software 4) Calculate the correlation ship between the variables analyzed. It follows the cities of São Carlos, SP and Belem, PA as examples of analysis; the first city participates with 11% in the energy consumption used in environmental conditioning in the residential sector and the second city participates with 40%. Changes were made in the materials of walls and roofs, trying to identify the differences of embodied energy and electricity consumption. The data obtained were worked in Excel spread sheets for further analysis and conclusion of the data. It was identified a strongly correlation coefficient between the analyzed variables.

CO2 is one of the main gases accountable for the increment of the greenhouse effect, of climate changes, and of environmental degradation arising from this ecological unbalance. Civil construction is one of the main sources of CO2 emissions, using construction techniques that are more sustainable can contribute to the reduction of those emissions. Furthermore, the energy content of materials must be taken into account as well due to the fact that the consumption of petroleum by-products increases the CO2 indexes in the atmosphere. It becomes then clear that the less energy is consumed, even those renewable, the less environmental impact there is. Thus, it is indispensable to analyse not only the emissions of CO2 but also the energy content of materials used in three roofing technologies under scrutiny in this research: green roofs, fibre cement, and ceramic tiles. Green roofs are a sustainable alternative to be implemented in covering the top of buildings. This research, therefore, aims to compare the CO2 emission to the energy content of two green roof solutions and of two traditional coverage solutions in the pre-operational phase in the cities of Porto Alegre and Santa Maria, both in the state of Rio Grande do Sul. The method used to identify left from the layers and constituents in each green cover, and the raw materials used in traditional roofs, measuring how much material was used for each cover, analyzing all the material traversed by the means of transport, quantifying emissions CO2 and energy consumption of materials by processes fabrication them and finally to compare all results. Common belief is that green roofs have the potential to mitigate environmental damages, especially those caused by the civil construction sector concerning CO2 emissions and energy consumption in the pre-operational phase, just as advantages in the operational phase are described. Such hypothesis was confirmed for the tested cover. However, among the possibilities discussed below for closing the top of buildings, green roofs are the only technology capable of mitigating environmental damage, in particular, the emission of carbon dioxide, and provide an environmental service to the community carbon sequestration to throughout his life . Nonetheless, amongst the building coverage possibilities herein analysed, green roofs are the only technology capable of integrally mitigating environmental damages in a few years, especially the emission of carbon dioxide, and also the only technology capable of providing an environmental service to the collectivity of carbon sequestration to throughout his life. / O CO2 é um dos principais gases responsáveis pelo incremento do efeito estufa, das mudanças climáticas e da degradação ambiental decorrente deste desequilíbrio ecológico. Sendo a construção civil uma das principais responsáveis pela emissão de CO2, o uso de técnicas construtivas mais sustentáveis pode contribuir para a redução dessas emissões. Além disso, o conteúdo energético dos materiais também é importante ser considerado, pois além de incrementar, através de consumo de derivados de petróleo, os índices de CO2 na atmosfera, o menor consumo de energia possível, mesmo as renováveis, representa menores impactos ambientais. Assim sendo, imprescindível analisar não só a emissão de CO2, como também o conteúdo energético dos materiais empregados nas três tecnologias de cobertura objetos de estudo desta pesquisa: coberturas verdes, de fibrocimento e de telhas cerâmicas. As coberturas verdes são uma possibilidade sustentável a ser implementada no fechamento de topo de edificações. A presente pesquisa visa a comparar as emissões de CO2 e o conteúdo energético de duas soluções de cobertura verdes e duas soluções de coberturas tradicionais, na fase pré-operacional, localizadas em Porto Alegre e outra em Santa Maria RS. O método utilizado partiu desde identificar as camadas e elementos constituintes em cada cobertura verde, bem como os insumos utilizados nas coberturas tradicionais, mensurar quanto material foi utilizado para cada cobertura, analisar o percorrido de todos os materiais pelos meios de transportes, quantificar as emissões de CO2 e o consumo energético dos materiais pelos processos de fabricações dos mesmos e finalmente comparar todos os resultados. O senso comum considera que as coberturas verdes têm o potencial de mitigar danos ambientais, especialmente os causados pelo setor da construção civil de emissão de CO2 e de consumo energético na fase pré-operacional, da mesma forma como são descritas as vantagens na fase operacional. Tal hipótese se confirmou para as coberturas avaliadas. Dentre as possibilidades aqui analisadas para fechamento de topo de edificações, as coberturas verdes são a única tecnologia capaz de mitigar os danos ambientais, em especial, a emissão de dióxido de carbono, e fornecer um serviço ambiental à coletividade de sequestro de carbono ao longo de sua vida útil.