How to calculate the environmental impact of renewable energy

International audienceThe development of renewable energy since the early 2000s should continue and intensify in the coming years, changing significantly the electricity mix of the future while reducing the associated environmental impacts. It is therefore crucial to study the environmental impact of the different production sectors

Comment calculer l’impact environnemental des énergies renouvelables ?

International audienceL'essor des renouvelables depuis le début des années 2000 devrait se poursuivre et s'amplifier dans les décennies à venir. Elles modifieront substantiellement le bouquet électrique du futur et on espère qu'elles limiteront les impacts environnementaux associés à la production d’électricité. Il est donc indispensable d'étudier l'empreinte environnementale des différentes filières de production

Essence of indecision - explaining Veto Player structures and Agenda Setting processes in Swiss Foreign Policy

The Swiss foreign policy offers a deviant case. Most countries that were neutral during the Cold War have during the last decades become more cooperative, while Switzerland on the other hand still contains a rather stable foreign policy. Because traditional theories in International Politics offer no concrete explanation to this puzzle, I have been oriented towards decision-making theories in domestic politics. The research questions were explored through two case studies. The first case study analysing the veto player structures in the Swiss security reports 1973- 2010 with help of Tsebelis Veto Player Theory (1995). Finding that not all institutional veto players favoured the proposed changes in the security reports. The consent of all three veto players is however necessary in order to change a policy, leading therefore to no change. The second case study examines the agenda-setting process in the UN membership proposal in 1986 with help of Kingdon´s Multiple Stream Framework (1995). Finding that the prominent actors in the governmental agenda and the decision agenda differed, explaining therefore why the UN membership was rejected. In both case studies the people through the referendum’s where identified as the most sufficient factor influencing the decision-making process in the Swiss foreign policy

Female Labor Supply and Child Care in France

We use French household data to estimate a structural model of female labor supply and use of paid child care outside the home. Child care costs are found to have little impact on the labor market participation decision of mothers. The model is used to study various policy issues. The influence of the current tax credit on child care expenditures on the mothers’ labor supply is weak. Suppressing the APE (Parental Allowance for the Education) would cause the female participation rate in our sample to rise by 4 points and the proportion of mothers using paid care to rise by 2 points. The responses of women to policy changes are very heterogenous. Macroeconomic changes in female labor supply are equally due to switches between non-participation and participation and switches between working hours by working women.female labor supply, child care, welfare participation, fiscal policy

Environmental assessment of electricity scenarios with Life Cycle Assessment

International audienceThe environmental impacts of existing electricity generation systems have already been assessed with Life Cycle Assessment (LCA) studies. However environmental impacts assessment of scenarios is very rarely evaluated through a life cycle perspective partly because of the complex parameters it involves, such as the temporal technology variation and the spatial dependency per country. Moreover some studies only analyze the effect of limited indicators variation. Considering these parameters is however crucial when steering and evaluating policy options with regards to the possible environmental consequences. The main objective of this paper is to present the methodology undertaken to perform an LCA for energy scenarios through the analysis of environmental impacts. Such methodology has been applied to a specific scenario, a "Renewable" scenario and results are analysed for Austria. This scenario has been developped within EnerGEO European project

Eco-design of buildings and comparison of materials

International audienceSustainable building integrates many issues, for instance: reducing energy consumption while keeping a high level of thermal comfort (in winter as well as in summer conditions), global environmental problems such as global warming or ozone depletion, indoor air quality issues, relevant material resource and waste management. Such issues are highly related to the choice of building materials. Eco-design requires therefore a relevant integrated assessment for the building materials not only at the process stage but over the whole life cycle of the buildings including the dominant use phase. Life Cycle Assessment (LCA) applied to buildings is enlarging the scope of material assessment. An innovative approach, EQUER (Evaluation of environmental quality of buildings), has been developed at Ecole des Mines for architects and consultants by linking a life cycle simulation tool with a building thermal simulation. The life cycle inventory database Ecoinvent is used to evaluate the environmental impacts of material fabrication and other processes (energy, transport,...). There are still many uncertainties and limits to the present state of the art of LCA. The uncertainties concern both the data (inventories) and impact indicators. For instance, the global warming potential (GWP) of other gases than CO2 is known with a high rate of uncertainty. Global indicators related to human or eco-toxicity are doubtful because the location of the emissions is not considered: in fact air pollution inside buildings do have a much larger effect than diluted external emissions and no indoor indicator has yet been elaborated. Also, the processes occurring at the end of the building life cycle are difficult to foresee, particularly because buildings are generally long lasting (though it may be assumed that mixing materials -concrete with polystyrene or wood for instance- will make the future waste management more difficult). Despite these limits, an attempt to convert these inventories data into a meaningful environmental profile is proposed in order to perform sensitivity studies for different building materials and derive environmental material performance according to a specific building use. We propose here a contribution concerning the evaluation of quantifiable environmental impacts of buildings for different material choices and end of life scenarios. The output of the software is an eco-profile including the different CML indicators (global warming, acidification, eutrophication potentials, smog, etc.), IMPACT2002+ indicators (human toxicity and ecosystem quality) plus some aggregated values like primary energy and water consumption, generation of radioactive and other waste. These indicators are given either for the different phases or for different alternatives or projects. The methodology is presented and illustrated by a comparative study on a single family house, concerning the comparison of three structural materials: concrete blocks, bricks, and timber. The results of this exercise are presented and its limits are discussed

Evaluation of Environmental Accounting Methodologies for the assessment of global environmental impacts of traded goods and services.

Environmental accounting methods (EAM) are currently getting a strong interest from political entities, multinational corporations and citizens. EAMs are applied to a large range of socio-techno-economic activities for monitoring and managing their environmental performance over time: at macro-level to implement the environmental pillar of sustainable development, at meso-level for companies reporting and at micro-level for comparing the environmental footprints of products. IMEA project (IMports Environmental Accounting) is a SKEP-Era-net project (Scientific Knowledge for Environmental Protection) aiming at assessing the potential of EAMs to consider the challenges from globalization and environmental impacts linked to international trade. It was lead by MINES ParisTech/ARMINES with partners from the Institute of Social Ecology, Vienna, TNO, University of Oulu, and VITO, carried out between June 2008 and September 2009. The global aim of IMEA is to provide elements to answer the following question: "Does a given EAM meet societal expectations and how does it cope with new challenges from globalization?". IMEA has focused on the analysis of these challenges based on what EAMs "are", "how" they function and the use of their results in decision-making by the means of an archetypical workflow and an analytical framework. Based on this comprehensive analytical framework, the following EAMs. have been assessed in detail: Life Cycle Assessment, Economy-Wide Material Flow Analysis, Physical Input Output Tables, Environmentally Extended Input-Output Analysis, land use indicators like the Human Appropriation of Net Primary Production, the Actual Land Demand or the Ecological Footprint, and the Water Footprint

Simplified prospective LCA models for residential PV installations based on SC-SI installed in Europe in 2050

International audienceThe prospective environmental impacts and electricity production capacity of residential PV systems need to be assessed for an efficient implementation planning while minimizing their environmental impacts. These impacts must be assessed using a life cycle approach, such as Life Cycle Assessment (LCA). This study is reporting the steps towards a simplified prospective model valid for residential PV systems based on single-crystalline silicon (sc-Si), installed in Europe around 2050. Prospective greenhouse gas (GHG) performance of PV installations are compared to current situation (2011-2013) accounting for technological improvements, future electricity mixes and module manufacturing origin. Recommendations to develop a simplified prospective LCA model are provided

Reproduction de l'ordre institutionnel face à l'incertitude

Comment certains systèmes se maintiennent-ils malgré un environnement incertain et changeant ? Cette question reste peu explorée dans la littérature, en particulier en ce qui concerne la compréhension des efforts des acteurs pour reproduire des croyances et des schémas de pensée. Dans cette perspective, les auteurs focalisent l'attention sur le discours des majors du disque dans la filière musicale et déterminent leur rôle dans la relative persistance de l'ordre existant.théorie néo-institutionnaliste, maintien institutionnel, analyse de discours, industrie musicale

Hydrogen embrittlement susceptibility of a high strength steel X80

The present paper deals with hydrogen embrittlement (HE) susceptibility of a high strength steel grade (X80). The respective implication of different hydrogen populations, i.e. adsorbed, dissolved in interstitial sites, trapped on dislocations and/or microstructural elements on the associated embrittlement mechanisms has been addressed through mechanical testing in high pressure of hydrogen gas at room temperature. Tensile tests at various strain rates and hydrogen pressures have been carried out. Moreover, changes of gas (hydrogen or nitrogen) during loading have been imposed in order to get critical experiments able to discriminate among the potential hydrogen embrittlement mechanisms already proposed in the literature. The results of these tests have shown that hydrogen induces several kind of damages including decohesion along ferrite/pearlite interfaces and microcracks initiations on the specimens external surface. It is shown that decohesion is not critical under the loading paths used in the present study. On the contrary, it appears that the external microcracks initiation, followed by a quasi-cleavage fracture, is responsible for the premature failure of the material in high pressure of hydrogen gas. These experimental results have been further discussed by modeling hydrogen diffusion in order to identify hydrogen populations (adsorbed, diffusible or trapped) involved in HE. It was then demonstrated that adsorbed and near surface diffusible hydrogen are mainly responsible for embrittlement