Recent literature has recommended that life cycle assessments (LCA) of forest bioenergy supply chains consider the impact of biomass harvest on ecosystem carbon stocks as well as the net emissions arising from combustion of various forms of biofuels compared with reference fossil fuel systems. The present study evaluated the magnitude and temporal variation of ecosystem C stock changes resulting from harvest of roadside residues and unutilized whole trees for bioenergy. The Carbon Budget Model (CBM-CFS3) was applied to the Gordon Cosens Forest, in northeastern Ontario, along with the Biomass Opportunity Supply Model (BiOS-Map), for cost analysis of different types of biomass comminution. Natural gas (NG) steam and electricity, grid electricity, and coal electricity reference systems were analyzed for a pulp and paper mill. The findings showed that the forested landscape becomes a net sink for carbon following the 20th year of roadside residue harvest, compared to whole-tree harvest, where the forested landscape remained a net source of carbon over the entire 100 year rotation. The cumulative ecosystem carbon loss from whole-tree harvest was 11 times greater compared to roadside residue harvest. BiOS-Map analysis suggested that due to technical and operational limits, between 55%-59% and 16%-24% of aboveground biomass was not recovered under roadside residue and whole-tree harvest respectively. The cost of delivering roadside residues was estimated at $52.32/odt–$57.45/odt, and for whole trees $92.63/odt–$97.44/odt. The Life Cycle Assessment (LCA) analysis showed break-even points of 25, 33 and 6 years for roadside residues displacing NG steam, NG electricity, and coal, respectively. No GHG reduction was achieved when forest biomass was used to displace grid electricity that is generated in Ontario. Whole-tree bioenergy resulted in no GHG reduction for NG displacement, and a break-even point of 70-86 years for coal. A net GHG reduction of 67% and 16% was realized when roadside residues and whole trees were used to displace coal, compared to 45% and 38% when roadside residues were used to displace NG steam and NG electricity, respectively. Therefore, it is recommended that bioenergy deployment strategies focus on the utilization of roadside residues, if the main goal is GHG mitigation.

根據歐盟2009 年發布之再生能源指令，定義熱泵系統所擷取之大氣熱能、水熱能以及地熱能為再生能源之選項，熱泵技術不受日夜與天候影響，且具安全、有低耗能、低排碳的優點，可應用在空調、暖氣、熱水等設備，備受歐美日本等先進國家重視，也是歐美各國政府極力推廣的項目之一。本研究針對台灣地區家戶住宅所使用小型空氣源熱泵熱水機組，透過環境資源及能源效率的角度，來探討熱泵熱水系統對於台灣住宅部門的適用性。 在研究方法上，針對國內熱泵個案廠商進行系統盤查分析，並且估算使用運轉過程中所需之能源投入，以計算熱水系統在製造過程與運轉使用過程中之環境影響。選擇生命週期評估軟體SimaPro 7.3做為評估工具，使用Eco-Indicator 95、EPS 2000兩種衝擊評估模式，來以生命週期評估探討熱泵熱水系統對環境之影響。並輔以淨能源分析法中能源投資報酬率與能源回收期，以及估算熱泵熱水系統生命週期CO2排放量，來衡量熱泵熱水系統之能源效率是否具有其效益。並進一步針對不同的再生能源發電比例與提升熱泵能源效率比例，探討不同方案的敏感度分析。 根據本研究分析結果顯示，熱泵熱水系統不管從Eco-indicator 95或EPS 2000衝擊評估模式下，運轉使用階段對環境衝擊較大，主要的衝擊項目為重金屬汙染，是因為熱泵熱水系統運轉所使用的電力消耗所致。使用熱泵熱水系統對環境衝擊程度遠較電熱水系統來得小，雖在Eco-indicator 95之衝擊評估模式下，瓦斯熱水系統較熱泵熱水系統環境衝擊程度較小，但以EPS 2000衝擊評估模式下，熱泵熱水系統對環境是最為友善的熱水系統。以淨效益估算熱泵熱水系統源投資報酬（EROI）值為1.45～5.55，能源回收期約為0.22年至2.16年，表示熱泵熱水系統從生命週期的角度來檢視能源效率是具有效益的。由於目前熱泵熱水系統對環境最大的負擔來源是電力的使用，若未來能提高再生能源發電比例、降低臺灣電能含碳濃度，或者提高熱泵能源生產效率，均能降低熱泵熱水系統對環境的負面影響。 / The purpose of this study is to apply life cycle assessment (LCA) and net energy analysis to explore the environmental impacts of the heat pump water heater in Taiwan. In order to achieve this objective, domestic data inventory was gathered from local heat pump industry in Taiwan through questionnaires including input of energy, product output and waste, etc. The SimaPro7.3 program and two impact assessment methods including Eco-Indicator 95, EPS 2000 were utilized to evaluate the environmental impact of the heat pump water heater. Also, we used net energy analysis such as energy return on investment and energy payback time, and estimated the life-cycle CO2 emissions to see whether if the heat pump water heater has its energy efficiency. In addition, the sensitivity analysis was performed by varying renewable energy generation portfolio and the heat pump energy efficiency ratio. Emprical results of two impact assessment methods (Eco-indicator 95 and EPS 2000) show that the main impact on environment of heat pump water heater is from operation phase. When operating the heat pump water heater, it needs to consume electricity which is generated from fossil fuel and caused the environmental impact. Compared with the electric water heater, the environmental impact degree of heat pump water heater is much smaller. In Eco-indicator 95 method, gas water heater has less influence on the environment than heat pump water heater; however, heat pump water heater is the most environment-friendly system in EPS 2000 method. That is because gas is a kind of nonrenewable resource. From the viewpoint of resource stock, gas indeed influence “Depletion of reserves” of environmental impact. By utilizing net energy analysis, the estimated energy return on investment (EROI) of heat pump water heater is 1.45～5.55, and energy payback time is 0.22~2.16 years. It indicates that heat pump water heater has significant benefit from life-cycle perspective. The main impact to environment by heat pump water heater is essentially derived from electricity input. To mitigation this environmental issue, one can reduce environmental impact by increase the proportion of renewable energy generation, and reducing the electricity CO2 emission. Furthermore, improving the energy efficiency of the heat pump would also helpful.

I Sverige står bostadssektorn för mer än en tredjedel av landets energianvändning. Byggnader måste minska sin energianvändning för att således kunna uppfylla framtida lagkrav om maximal tillåten energianvändning, men också för att minska påverkan till global uppvärmning. Ytterligare en problematik som råder, däribland i Sverige, är bostadsbrist. Kommunala bostadsbolag står inför utmaningen att kunna bygga bostäder snabbt, billigt och miljövänligt för att minska bostadsbristen i landet. Ett sätt att studera två av tre hållbarhetsaspekter vid val av framtida bostadsbyggande är att utföra en livscykelanalys (LCA) och livscykelkostnadsanalys (LCC) kring de tilltänkta husen. LCA:er indikerar vilken miljöpåverkan en produkt förorsakar under dess livslängd. LCC:er avser att studera vilka kostnader produkter ger upphov till under en given analysperiod. Det svenska kommunala bostadsbolaget Stångåstaden AB står inför utmaningen kring bostadsbrist och vill bygga hållbara bostäder. Bostadsbolaget har önskat en jämförande LCA och LCC av två verkliga flerbostadshus som de genom ramavtal kan upphandla, detta är utgångspunkten för denna studie. Den ena byggnaden har stomme av betong, den andra har stomme av trä. Husen är tänkta att placeras i utkanten av Linköping, Sverige. Studien har valt att analysera miljöpåverkan från husens olika livscykelfaser samt kostnader över analysperioden 50 år. Utöver detta studeras även vilka energieffektiviseringsåtgärder (EEÅ) till byggnaderna som är optimala att genomföra för att öka den termiska prestandan hos huskonstruktionerna. Från litteraturen finns det relativt få studier som kombinerar både LCA och LCC för vanligt förekommande hustyper i städer. I dess standardfall påvisade resultatet från LCA:n att huset med betongkonstruktion hade något lägre påverkan i sex av sju studerade miljöpåverkanskategorier, jämfört med flerbostadshuset i trä. Resultatet skilde sig lite åt då annan typ av indata användes. Vad gäller kostnader under husens livslängd var huset i trä ungefär 20 % dyrare jämfört med huset med betongkonstruktion. Trots annan typ av indata var träkonstruktionen dyrare än betongkonstruktionen. Med en kalkylränta på 7,5 % var det inte lönsamt att genomföra EEÅ för husen, med halverad kalkylränta blev det dock lönsamt att tilläggsisolera krypgrunden i huset med trästomme. Fler studier behöver utföras för att generalla slutsatser ska kunna dras kring vilket konstruktionsmaterial som är mest hållbart. Denna studie baseras på två specifika fall. Samma resultat kan eventuellt inte förväntas för andra byggnader med stomme i betong och trä. / The residential sector accounts for more than a third of the energy use in Sweden. To reduce the energy use of buildings is a necessity in order to meet future regulationof maximum allowable energy, but also important to reduce the impact on global warming. Another complexity arising in Sweden is the shortage of accommodation. Municipal housing corporations face the challenge of constructing residences fast, cheap and with concern of environmental effects in order to reduce the shortage of accommodation. One way of assessing two of the three aspects of sustainability when looking at future construction of residential buildings is to carry out a Life Cycle Assessment (LCA) and a Life Cycle Cost Assessment (LCCA). An LCA can indicate what kind of environmental impact a product causes over its lifetime and the LCC allows for assessing what types of costs are associated with the product. For the municipal housing corporation Stångåstaden AB the shortage of accommodation is a reality and their mindset is sustainable construction of residences. This study was conducted upon request from Stångåstaden who wanted a comparative LCA and LCCA between two prefabricated multi-residential buildings that are available to them through a framework agreement. The first building has a concrete foundation and the second one is made of wood. The houses are planned to be placed at the outskirts of Linköping, Sweden. The focus of this study has been to comparatively assess the environmental impact from the different life cycle phases and the economic costs of the two buildings during a time period of 50 years. Moreover, the thesis also analyze the optimal retrofit strategy for the buildings in order to find the optimal (lowest) life cycle cost. Furthermore, the current literature has conveyed relatively few studies that combine both LCA and LCC methodology for house types that are common in most towns. The result from the LCA indicated that the house with concrete construction had a little less impact in six of the seven studied environmental impact categories compared to the house made of wood. The result differed slightly when the input data were changed. Regarding the LCCA the house made of wood was roughly 20 % more expensive than its concrete counterpart. Changing the input data revealed no difference in the result. With an interest rate of 7,5 % no retrofits were profitable for either building, however reducing the interest rate to half its original value made it cost optimal to increase the floor insulation for the house made of wood. More studies should be conducted to be able to draw general conclusions regarding which construction material that is the most sustainable. This thesis is based on two specific and real cases. The same result could possibly not be expected from other studies comparing buildings with concrete and wood construction.

En raison de la demande croissante d’énergie dans le monde et des nombreux dommages causés par l’utilisation des énergies fossiles, la contribution des énergies renouvelables a augmenté de manière significative dans le mix énergétique global dans le but de progresser vers un développement plus durable. Dans ce contexte, ce travail vise à l’élaboration d’une méthodologie générale pour la conception de systèmes photovoltaïques, basée sur les principes d’écoconception, en tenant compte simultanément des considérations technico-économiques et environnementales. Afin d’évaluer la performance environnementale des systèmes PV, une technique d’évaluation environnementale basée sur l’Analyse du Cycle de Vie (ACV) a été utilisée. Le modèle environnemental a été couplé d’une manière satisfaisante avec le modèle de conception d’un système PV connecté au réseau pour obtenir un modèle global, apte à un traitement par optimisation. Le modèle de conception du système PV résultant a été développé en faisant intervenir l’estimation du rayonnement solaire reçu dans une zone géographique concernée, le calcul de la quantité annuelle d’énergie produite à partir du rayonnement solaire reçu, les caractéristiques des différents composants et l’évaluation des critères technico-économiques à travers le temps de retour énergétique et le temps de retour sur investissement. Le modèle a ensuite été intégré dans une boucle d’optimisation multi-objectif externe basée sur une variante de l’algorithme génétique NSGA-II. Un ensemble de solutions du Pareto a été généré représentant le compromis optimal entre les différents objectifs considérés dans l’analyse. Une méthode basée sur une Analyse en Composantes Principales (ACP) est appliquée pour détecter et enlever les objectifs redondants de l’analyse sans perturber les caractéristiques principales de l’espace des solutions. Enfin, un outil d’aide à la décision basé sur M- TOPSIS a été utilisé pour sélectionner l’option qui offre un meilleur compromis entre toutes les fonctions objectifs considérées et étudiées. Bien que les modules photovoltaïques à base de silicium cristallin (c-Si) ont une meilleure performance vis-à-vis de la production d’énergie, les résultats ont montré que leur impact environnement est le plus élevé des filières technologiques de production de panneaux. Les technologies en « couches minces » présentent quant à elles le meilleur compromis dans tous les scénarios étudiés. Une attention particulière a été accordée aux processus de recyclage des modules PV, en dépit du peu d’informations disponibles pour toutes les technologies évaluées. La cause majeure de ce manque d’information est la durée de vie relativement élevée des modules photovoltaïques. Les données relatives aux procédés de recyclage pour les technologies basées sur CdTe et m-Si sont introduites dans la procédure d’optimisation par l’écoconception. En tenant compte de la production d’énergie et du temps de retour sur énergie comme critères d’optimisation, l’avantage de la gestion de fin de vie des modules PV a été confirmé. Une étude économique de la stratégie de recyclage doit être considérée et étudiée afin d’avoir une vision plus globale pour la prise de décision. / Because of the increasing demand for the provision of energy worldwide and the numerous damages caused by a major use of fossil sources, the contribution of renewable energies has been increasing significantly in the global energy mix with the aim at moving towards a more sustainable development. In this context, this work aims at the development of a general methodology for designing PV systems based on ecodesign principles and taking into account simultaneously both techno-economic and environmental considerations. In order to evaluate the environmental performance of PV systems, an environmental assessment technique was used based on Life Cycle Assessment (LCA). The environmental model was successfully coupled with the design stage model of a PV grid-connected system (PVGCS). The PVGCS design model was then developed involving the estimation of solar radiation received in a specific geographic location, the calculation of the annual energy generated from the solar radiation received, the characteristics of the different components and the evaluation of the techno-economic criteria through Energy PayBack Time (EPBT) and PayBack Time (PBT). The performance model was then embedded in an outer multi-objective genetic algorithm optimization loop based on a variant of NSGA-II. A set of Pareto solutions was generated representing the optimal trade-off between the objectives considered in the analysis. A multi-variable statistical method (i.e., Principal Componet Analysis, PCA) was then applied to detect and omit redundant objectives that could be left out of the analysis without disturbing the main features of the solution space. Finally, a decision-making tool based on M-TOPSIS was used to select the alternative that provided a better compromise among all the objective functions that have been investigated. The results showed that while the PV modules based on c-Si have a better performance in energy generation, the environmental aspect is what makes them fall to the last positions. TF PV modules present the best trade-off in all scenarios under consideration. A special attention was paid to recycling process of PV module even if there is not yet enough information currently available for all the technologies evaluated. The main cause of this lack of information is the lifetime of PV modules. The data relative to the recycling processes for m-Si and CdTe PV technologies were introduced in the optimization procedure for ecodesign. By considering energy production and EPBT as optimization criteria into a bi-objective optimization cases, the importance of the benefits of PV modules end-of-life management was confirmed. An economic study of the recycling strategy must be investigated in order to have a more comprehensive view for decision making.

L’objectif de ce travail est de développer un cadre méthodologique et générique d’éco-conception de procédés chimiques couplant des outils de modélisation et de simulation traditionnels de procédés (HYSYS, COCO, ProSimPlus et Ariane), d’Analyse du Cycle de Vie (ACV), d’optimisation multiobjectif basée sur des Algorithmes Génétiques et enfin des outils d’aide à la décision multicritère (ELECTRE, PROMETHEE, M-TOPSIS). Il s’agit de généraliser, d’automatiser et d’optimiser l’évaluation des impacts environnementaux au stade préliminaire de la conception d’un procédé chimique. L’approche comprend trois étapes principales. Les deux premières correspondent d’une part aux phases d’analyse de l’inventaire par calcul des bilans de matière et d’énergie et d’autre part à l’évaluation environnementale par ACV. Le problème du manque d’information ou de l’imprécision dans les bases de données classiques en ACV pour la production d’énergie notamment sous forme de vapeur largement utilisée dans les procédés a reçu une attention particulière. Une solution proposée consiste à utiliser un simulateur de procédés de production d’utilités (Ariane, ProSim SA) pour contribuer à alimenter la base de données environnementale en tenant compte de variations sur les conditions opératoires ou sur les technologies utilisées. Des sous-modules « énergie » sont ainsi proposés pour calculer les émissions relatives aux impacts liés à l’utilisation de l’énergie dans les procédés. La troisième étape réalise l’interaction entre les deux premières phases et l’optimisation multi-objectif qui met en jeu des critères économiques et environnementaux. Elle conduit à des solutions de compromis le long du front de Pareto à partir desquelles les meilleures sont choisies à l’aide de méthodes d’aide à la décision. L’approche est appliquée à des procédés de production continus : production de benzène par hydrodéalkylation du toluène HDA et production de biodiesel à partir d’huiles végétales. Une stratégie à plusieurs niveaux est mise en oeuvre pour l'analyse de l'optimisation multi-objectif. Elle est utilisée dans les deux cas d'étude afin d'analyser les comportements antagonistes des critères. / The objective of this work is to propose an integrated and generic framework for eco-design coupling traditional modelling and flowsheeting simulation tools (HYSYS, COCO, ProSimPlus and Ariane), Life Cycle Assessment, multi-objective optimization based on Genetic Algorithms and multiple criteria decision-making methods MCDM (Multiple Choice Decision Making, such as ELECTRE, PROMETHEE, M-TOPSIS) that generalizes, automates and optimizes the evaluation of the environmental criteria at earlier design stage. The approach consists of three main stages. The first two steps correspond respectively to process inventory analysis based on mass and energy balances and impact assessment phases of LCA methodology. Specific attention is paid to the main issues that can be encountered with database and impact assessment i.e. incomplete or missing information, or approximate information that does not match exactly the real situation that may introduce a bias in the environmental impact estimation. A process simulation tool dedicated to production utilities, Ariane, ProSim SA is used to fill environmental database gap, by the design of specific energy sub modules, so that the life cycle energy related emissions for any given process can be computed. The third stage of the methodology is based on the interaction of the previous steps with process simulation for environmental impact assessment and cost estimation through a computational framework. The use of multi-objective optimization methods generally leads to a set of efficient solutions, the so-called Pareto front. The next step consists in identifying the best ones through MCDM methods. The approach is applied to two processes operating in continuous mode. The capabilities of the methodology are highlighted through these case studies (benzene production by HDA process and biodiesel production from vegetable oils). A multi-level assessment for multi-objective optimization is implemented for both cases, the explored pathways depending on the analysis and antagonist behaviour of the criteria.

Cette thèse de doctorat, a consisté, dans une première partie, à introduire d’une part, la notion de l’analyse du cycle de vie « ACV » et celle des biocarburants. D’autre part, à présenter l’intérêt d’appliquer une ACV sur des biocarburants afin de valoriser leurs bilans énergétiques et analyser leurs impacts environnementaux face aux carburants conventionnels. Dans une deuxième partie, nous avons comparé, d’un point de vue énergétique et environnemental, 3 scénarios de production d’électricité : 2 scénarios de cogénération (turbine à vapeur et ORC) pour la production d’énergie électrique et thermique à partir de biomasse, et un scénario de cogénération par moteur diesel. Ces scénarios sont comparés à l’aide de deux méthodes orientées « analyse des dommages »: Eco-indicateur 99 (E) et IMPACT2002+Dans une troisième partie, on a abordé la valorisation du biogaz sous forme de carburant dans des moteurs "dual fuel" pour des engins agricoles dans le but de déterminer l’impact environnemental lié à l’utilisation de ce carburant alternatif au diesel par rapport aux autres biocarburants. Les méthodes Eco-indicateur 99 (E) et CML ont été utilisées ici. On a pu ainsi identifier les principaux polluants générés à chaque étape du cycle de vie de l’agrocarburant et les étapes qui ont les plus grands impacts environnementaux et on a identifié, selon nos critères et par rapport au contexte, le scénario énergétique le plus compatible avec le principe de développement durable. / This thesis has consisted in a first part to introduce, on one hand, the concept of each of: lifecycle assessment "LCA" and biofuels, on the other hand, to present the benefits of applying aLCA on biofuels to evaluate their energy balances and to analyze their environmental impactsagainst conventional fuels.In a second part, we compared, from point of view energetic and environmental, 3 scenariosof electricity production: 2 scenarios of cogeneration (steam turbine and ORC) for theproduction of electrical energy and of heat from biomass, and a scenario of cogeneration by adiesel engine, these scenarios have been compared using two damage-oriented analysismethods: Eco-indicator 99 (E) and IMPACT2002 +In a third part, we worked on the evaluation of methane as fuel in "dual fuel" engines foragricultural purpose, the aim was to determine the environmental impact associated with theuse of this alternative fuel for diesel compared to other biofuels. Methods Eco-indicator 99(E) and CML have been used here.We were able to identify the main pollutants generated at each stage of the life cycle ofbiofuel and the steps that have the greatest environmental impacts, and to identify, accordingto our criteria and to the context the energy scenario the most consistent with the principle ofsustainable development.

Alors que nous faisons face à une crise biologique majeure, acteurs institutionnel et ONGs exhortent les entreprises à s’engager pour enrayer cette érosion écologique. L’objectif de la thèse est d’analyser, évaluer et faire évoluer la contribution potentielle des entreprises à la conservation de la biodiversité dans le cadre de leur responsabilité sociétale (RSE).Un cadre d’analyse est développé pour évaluer la prise en charge par une entreprise de ses responsabilités écologiques en termes de moyens – les initiatives RSE a priori favorables à la biodiversité mises en œuvre – et de résultats – la compatibilité des activités de l’entreprise avec la conservation de la biodiversité. Après avoir caractérisé les initiatives RSE à partir de l’étude d’engagements d’entreprises endossés comme contributions à la Stratégie nationale pour la biodiversité, une méthode est proposée pour détecter si les activités d’une entreprise sont écologiquement non-durables. Le postulat est que le respect des capacités de charge des écosystèmes est un prérequis à la conservation effective de la biodiversité. Cette méthode, adaptée de l’évaluation environnementale absolue de la durabilité, est appliquée, dans le cadre de deux projets de recherche-intervention, au portfolio alimentaire du Groupe Casino et au cycle de vie de deux installations de stockage de déchets dangereux de SARP Industries. Des orientations stratégiques visant à éviter-réduire-compenser les pressions non durables sont proposées. Soulignant l’importance de renforcer la prise en charge des pressions étendues, cette thèse ouvre plus largement des perspectives pour les secteurs d’activité et les politiques publiques. / As we are experiencing a major biological crisis, institutional actors and NGOs are calling on businesses to engage efforts aiming at halting biodiversity loss. The objective of the thesis is to analyze and evaluate the potential contribution of corporate social responsibility (CSR) to biodiversity conservation.A framework is developed to analyze to which extent a company takes in charge its ecological responsibilities. After characterizing CSR initiatives based on the case study of business commitments to contribute to the French National Biodiversity Strategy, a method is proposed to test whether business activities exert unsustainable pressures on ecosystems. It is assumed that compatibility with ecosystems’ carrying capacities is a prerequisite for effective biodiversity conservation. This method, adapted from the “absolute environmental sustainability assessment” (AESA) approach, is applied in the context of research-intervention projects to the food portfolio of the mass-market retailer Groupe Casino and to the life cycle of two facilities of SARP Industrie specialized in the disposal and storage of hazardous waste. The comparison of the company’s environmental footprints with the ecological constraints is used to draw a comprehensive strategy based on the mitigation hierarchy. As our results highlight the opportunity to strengthen the management of extended pressures through CSR, possible implications for sectors and public policies are discussed.

Uma das formas mais integradas, completas e eficazes para a gestão ambiental de atividades produtivas é baseada no ciclo de vida do produto, sendo a avaliação do ciclo de vida sua principal ferramenta. O produto avaliado é o álcool etílico hidratado combustível, por ser passível de melhorias ambientais durante seu ciclo de vida, alternativo frente aos fósseis e de grande importância estratégica para o Estado de São Paulo e para o Brasil. O objetivo é a avaliação do ciclo de vida do álcool etílico hidratado combustível utilizando o método EDIP (Environmental Development of Industrial Products) e introduzindo as avaliações exergéticas e emergéticas na avaliação e valoração do impacto. A estrutura metodológica está baseada nas normas da série NBR-ISO 14.040 e ISO 14.040. Os resultados do EDIP mostram que a atividade da colheita de cana apresenta o maior potencial de impacto para o consumo de recursos renováveis, o aquecimento global, a formação fotoquímica de ozônio troposférico, a acidificação e a toxicidade humana. O preparo do solo apresenta maior potencial para o consumo de recursos não renováveis e para a ecotoxicidade da água. O trato cultural apresenta maior influência na eutrofização e na ecotoxicidade do solo. Pela exergia, verifica-se que, para cada litro de álcool consumido, há uma perda de exergia pelas emissões atmosféricas de seu ciclo de vida, considerando que 25% da cana colhida seja crua, equivalente à exergia de, aproximadamente, 1,38 litro de álcool. Pela emergia, 69% do consumo de energia solar equivalente é realizado pelo veículo automotor. Portanto, a fim de adequar ambientalmente o ciclo de vida do etanol hidratado combustível, indica-se a eliminação da queimada, a redução do uso de agrotóxicos, de combustível fóssil e formas mais eficientes de uso do álcool combustível. / One of the most integrated, complete and efficacious means for the environmental management of productive activities is based on the life cycle of the product, whose main tool is the life cycle assessment. The assessed product is the hydrated ethylic alcohol fuel because of the environmental improvement possibilities during its life cycle, an alternative for fossil fuel and its great strategic importance to Sao Paulo State and Brazil. The goal is the life cycle assessment of hydrated ethylic alcohol fuel using EDIP (Environmental Development of Industrial Products) method and introducing exergy and emergy methods on the impact assessment and valuation. The methodological structure is based on the norms NBR-ISO 14.040 and ISO 14.040 series. The EDIP results show that the sugar cane harvesting activity presents the highest potential impact for the renewable resources consumption, the global warming, the photochemical ozone formation, the acidification and the human toxicity. The soil preparation activity presents the highest potential for the non-renewable resources and the ecotoxicity in water. The cultivation activity presents the highest potential for the nutrient enrichment and the ecotoxicity in soil. With the exergy method, it is verified that for each liter of alcohol consumed, there is an exergy lost by the atmospheric emissions of its life cycle, considering 25% of the total sugar cane cultivated and harvested is not burned, which is equivalent to the exergy of, approximately, 1.38 liter of alcohol. By the emergy method, 69% of the equivalent solar energy consumption is performed by the vehicle. Therefore, in order to achieve an environmentally benign life cycle of the hydrated ethylic alcohol fuel, it is indicated the sugar cane burning elimination, pesticides and fossil fuel reduction and more efficient manners of using alcohol fuel.

L’Analyse du Cycle de Vie (ACV) est une méthode d’évaluation multicritère des impacts environnementaux des biens et services. A ces débuts, l’ACV, dite Attributionnelle (ACVA), s’est attachée à analyser les impacts environnementaux dans des situations statiques pour la réalisation d’études comparatives, la communication environnementale et le développement de produits. De récents développements méthodologiques ont vu l’émergence de l’ACV Conséquentielle (ACVC) qui vise à quantifier les impacts directs et indirects de changements, via les mécanismes de marchés, permettant ainsi l’évaluation de politiques publiques. Cette thèse vise à proposer un cadre méthodologique pour l’évaluation d’instruments de politiques publiques dans le secteur de l’élevage laitier en combinant ACV et modèles économiquesElle s’articule autour de trois axes : i) identification et caractérisation des performances environnementale de technologies de production laitières par ACVA ; ii) adaptation du modèle économique MATSIM-LUCA pour les besoins de la thèse ; iii) évaluation par ACVC des impacts environnementaux de la suppression des quotas laitiers et de l’introduction d’une prime à l’herbe en Europe. Les travaux réalisés fournissent : i) une première proposition méthodologique pour l’évaluation d’instruments de politiques publiques par ACVC dans le secteur de l’élevage et ii) plusieurs pistes d’amélioration nécessaires pour rendre la méthode opérationnelle pour les décideurs publics. / Life Cycle Assessment (LCA) is a multicriteria method to assess environmental impacts of goods and services. In its early stages, LCA, known as Attributional (ALCA), was used to assess environmental impacts in a status-quo situation for benchmarking, environmental communication and product development. Recent methodological developments led to Consequential LCA (CLCA), which aims to quantify direct and indirect impacts of changes, through market mechanisms, allowing for public policy assessment. The aim of this Ph.D. thesis is to develop a methodological framework to assess public policy instruments in the livestock sector by combining LCA and economic modellingThis thesis is organized into three axes: i) identification and characterization of environmental performances of dairy production technologies through ALCA; ii) adaptation of MATSIM-LUCA economic model to the needs of the thesis; iii) environmental impact assessment through CLCA of dairy quota removal and implementation of a grass premium in the European Union. This work provides i) initial development of a methodological framework for assessing public policy instruments in the livestock sector and ii) identification of several improvements needed to make the method operational for stakeholders.

In the pursuit of low-carbon, renewable energy sources one option with great potential in the UK is tidal energy. Specifically the proposed construction of the Swansea Bay Tidal Lagoon (SBTL) in South Wales has become one such discussed option. With a potential net annual output of 400 GWh and a 120-year lifetime the scheme represents a long-term and large-scale electricity production option. An assessment of carbon emissions and embodied energy (EE) of the lagoon’s life cycle was carried out. Total lifetime carbon emissions for the SBTL are in the region of 470,000 tCO2e and EE was found to be around 7,800 TJ. The assessment shows that the SBTL has significantly lower emissions per year than the existing National Grid mix and with emissions of around 0.01 kgCO2e/KWh is significantly lower than the UK emissions target of 0.07 kgCO2e/KWh. Energy payback of the SBTL was found to be in the region of 5.5 years. The use of dredged ballast infill sourced from within the area of the lagoon plays an important role in keeping emissions and energy use low; and is a key consideration when planning future tidal lagoon structures.