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Cette thèse a pour objectif d'évaluer l'efficacité des dispositifs publics qui visent à inciter les agents à rénover leur logement afin d'en réduire la consommation énergétique. Il s'agit de combiner les deux dimensions clés de l'évaluation ex-post de l'intervention : la dimension récapitulative qui revient à déterminer l'efficacité des mesures mises en œuvre et la dimension formative qui vise à comprendre les résultats obtenus et à identifier les voies d'amélioration. Cela nécessite dans un premier temps de réaliser une analyse détaillée des facteurs qui sont à l'origine du faible niveau d'investissements, qualifié de déficit d'efficacité énergétique (" energy efficiency gap "). Ce déficit est dû à la présence de défaillances de marchés, aux conséquences de la rationalité limitée des ménages, ainsi qu'aux difficultés de coordination entre agents en particulier dans le cadre de la copropriété. Dans un deuxième temps il convient d'analyser le déficit d'efficacité énergétique en comparant les prescriptions qui peuvent être issues des calculs utilisés en économie publique concernant les investissements à réaliser, avec les données issues des études de terrain sur les investissements effectifs. Cette analyse permet de bien identifier les critères de décisions des ménages et ainsi de comprendre comment les barrières à l'efficacité énergétique se manifestent. L'identification des différentes barrières permet alors, dans un troisième temps, de voir si les dispositifs d'incitations aujourd'hui en application en France permettent de lever tous les obstacles aux investissements d'amélioration énergétique. Il apparaît que la multitude de dispositifs mis en oeuvre ne peut suffire à réduire fortement le déficit d'efficacité énergétique. D'une part, certaines barrières ne sont pas levées car aucun outil approprié n'existe. D'autre part, certains facteurs de blocages ne sont que partiellement traités car l'utilisation pratique des outils diffèrent de leur conception théorique. Finalement, l'analyse des programmes de réhabilitation thermique des logements qui ont été engagés sur le territoire grenoblois permet de déterminer l'efficacité des dispositifs additionnels c'est à dire d'évaluer dans quelle mesure ces interventions " renforcées " permettent de lever les barrières qui n'ont pu l'être avec les dispositifs nationaux. La mise en perspective de ces quatre analyses successives - des causes du déficit ; de sa manifestation ; des instruments nationaux ; des programmes mis en œuvre à l'échelle locale - aboutit à la conclusion d'un nécessaire renforcement des mesures non financières pour l'accompagnement des agents afin d'amorcer la dynamique d'investissement et ainsi créer les conditions de l'efficacité des instruments économiques plus généraux. This PhD dissertation focuses on energy efficiency policies in housing. It aims at evaluating the effectiveness of public incentives designed to increase household's investment in energy efficiency of their dwelling. To reach this objective this research combines the two key dimensions of ex-post evaluation, i.e. summary and formative dimensions. The first one aims at knowing the effectiveness of public policies whereas the other one targets to understand what the public policies' consequences are and to identify ways for improvement. To reach this purpose, the research follows four steps. Firstly, it requires a detailed analysis to understand the origins of the energy efficiency gap. This gap can be explained by markets failures, consequences of bounded rationality and coordination problem between stakeholders, especially in multi-family dwellings. Secondly, the argument progresses by drawing a parallel between results from normative analysis and from observations of actual level of investments in thermal retrofit actions. It aims at identifying investment households' criteria and then at understanding how barriers to energy efficiency raise. Thirdly, thanks to the inventory of these various energy efficiency barriers it becomes possible to examine if the incentives currently implemented in France can remove them all. It appears that the national policy does not significantly reduce the energy efficiency gap. On the one hand, some barriers remain because no tool has been proposed to overcome them. On the other hand, some barriers are only partially eliminated because the practical use of tools differs from their theoretical design. Finally, using the analysis of retrofitting programs implemented on the Grenoble area this research assesses the effectiveness of additional incentives. The objective is to know to what extent these "reinforced" policies remove barriers still existing after national tools implementation. From these four successive analyses - causes, appearance of the energy efficiency gap, national tools, programs implemented at the local level - we conclude to a necessary strengthening of non-financial measures which support agents to initiate an investment dynamic and in the meanwhile to an increase of the reliability of economic tools, such as taxes or subventions.

Cette thèse a pour objectif d'évaluer l'efficacité des dispositifs publics qui visent à inciter les agents à rénover leur logement afin d'en réduire la consommation énergétique. Il s'agit de combiner les deux dimensions clés de l'évaluation ex-post de l'intervention : la dimension récapitulative qui revient à déterminer l'efficacité des mesures mises en œuvre et la dimension formative qui vise à comprendre les résultats obtenus et à identifier les voies d'amélioration. Cela nécessite dans un premier temps de réaliser une analyse détaillée des facteurs qui sont à l'origine du faible niveau d'investissements, qualifié de déficit d'efficacité énergétique (" energy efficiency gap "). Ce déficit est dû à la présence de défaillances de marchés, aux conséquences de la rationalité limitée des ménages, ainsi qu'aux difficultés de coordination entre agents en particulier dans le cadre de la copropriété. Dans un deuxième temps il convient d'analyser le déficit d'efficacité énergétique en comparant les prescriptions qui peuvent être issues des calculs utilisés en économie publique concernant les investissements à réaliser, avec les données issues des études de terrain sur les investissements effectifs. Cette analyse permet de bien identifier les critères de décisions des ménages et ainsi de comprendre comment les barrières à l'efficacité énergétique se manifestent. L'identification des différentes barrières permet alors, dans un troisième temps, de voir si les dispositifs d'incitations aujourd'hui en application en France permettent de lever tous les obstacles aux investissements d'amélioration énergétique. Il apparaît que la multitude de dispositifs mis en oeuvre ne peut suffire à réduire fortement le déficit d'efficacité énergétique. D'une part, certaines barrières ne sont pas levées car aucun outil approprié n'existe. D'autre part, certains facteurs de blocages ne sont que partiellement traités car l'utilisation pratique des outils diffèrent de leur conception théorique. Finalement, l'analyse des programmes de réhabilitation thermique des logements qui ont été engagés sur le territoire grenoblois permet de déterminer l'efficacité des dispositifs additionnels c'est à dire d'évaluer dans quelle mesure ces interventions " renforcées " permettent de lever les barrières qui n'ont pu l'être avec les dispositifs nationaux. La mise en perspective de ces quatre analyses successives - des causes du déficit ; de sa manifestation ; des instruments nationaux ; des programmes mis en œuvre à l'échelle locale - aboutit à la conclusion d'un nécessaire renforcement des mesures non financières pour l'accompagnement des agents afin d'amorcer la dynamique d'investissement et ainsi créer les conditions de l'efficacité des instruments économiques plus généraux. This PhD dissertation focuses on energy efficiency policies in housing. It aims at evaluating the effectiveness of public incentives designed to increase household's investment in energy efficiency of their dwelling. To reach this objective this research combines the two key dimensions of ex-post evaluation, i.e. summary and formative dimensions. The first one aims at knowing the effectiveness of public policies whereas the other one targets to understand what the public policies' consequences are and to identify ways for improvement. To reach this purpose, the research follows four steps. Firstly, it requires a detailed analysis to understand the origins of the energy efficiency gap. This gap can be explained by markets failures, consequences of bounded rationality and coordination problem between stakeholders, especially in multi-family dwellings. Secondly, the argument progresses by drawing a parallel between results from normative analysis and from observations of actual level of investments in thermal retrofit actions. It aims at identifying investment households' criteria and then at understanding how barriers to energy efficiency raise. Thirdly, thanks to the inventory of these various energy efficiency barriers it becomes possible to examine if the incentives currently implemented in France can remove them all. It appears that the national policy does not significantly reduce the energy efficiency gap. On the one hand, some barriers remain because no tool has been proposed to overcome them. On the other hand, some barriers are only partially eliminated because the practical use of tools differs from their theoretical design. Finally, using the analysis of retrofitting programs implemented on the Grenoble area this research assesses the effectiveness of additional incentives. The objective is to know to what extent these "reinforced" policies remove barriers still existing after national tools implementation. From these four successive analyses - causes, appearance of the energy efficiency gap, national tools, programs implemented at the local level - we conclude to a necessary strengthening of non-financial measures which support agents to initiate an investment dynamic and in the meanwhile to an increase of the reliability of economic tools, such as taxes or subventions.

Abstract The Antarctic and Greenland ice contains an almost direct record of past atmospheric CH 4 . The record over the last 200 years reveals a spectacular 150% increase of the CH 4 atmospheric mixing ratio since pre-industrial times. At the scale of a glacial-interglacial cycle the record shows a remarkable correlation with climatic changes, with high (low) CH 4 levels during warm (cold) periods. A striking feature of the glacial-interglacial CH 4 record is the presence of large and abrupt (at the scale of a century or less) changes during the last glaciation and glacial-interglacial transition. The classical interpretation for the origin of CH 4 changes prior to the industrial era involves mainly the wetland source. In the context of gas hydrates the question is to know whether the past ice-core record contains fingerprints of catastrophic hydrate release (CHR). We currently conclude that the available record shows no evidence for CHR but additional ice-core analyses are necessary to reach a more definitive conclusion.

Abstract The Antarctic and Greenland ice contains an almost direct record of past atmospheric CH 4 . The record over the last 200 years reveals a spectacular 150% increase of the CH 4 atmospheric mixing ratio since pre-industrial times. At the scale of a glacial-interglacial cycle the record shows a remarkable correlation with climatic changes, with high (low) CH 4 levels during warm (cold) periods. A striking feature of the glacial-interglacial CH 4 record is the presence of large and abrupt (at the scale of a century or less) changes during the last glaciation and glacial-interglacial transition. The classical interpretation for the origin of CH 4 changes prior to the industrial era involves mainly the wetland source. In the context of gas hydrates the question is to know whether the past ice-core record contains fingerprints of catastrophic hydrate release (CHR). We currently conclude that the available record shows no evidence for CHR but additional ice-core analyses are necessary to reach a more definitive conclusion.

Abstract Tidal circulation and tidal stream resource in Alderney Race (Raz Blanchard) were assessed by using a towed acoustic Doppler current profiler (ADCP) system and tidal modeling. Optimal Interpolation (OI) was applied to process the underway velocity measurements recorded at neap tide flood and ebb flow. The interpolation technique allows reconstructing space-time evolution of the velocity field within the domain during surveying periods. The method employs velocity covariances derived from numerical simulations by a 2D hydrodynamic model MARS. Model covariances are utilized by the OI algorithm to obtain the most likely evolution of the velocity field under the constraints provided by the ADCP observations and their error statistics. The resulting velocity fields were used for assessing the tidal stream resource at site. The largest overall difference between the kinetic power density derived from simulated and interpolated velocity fields was found for ebb tide. Model simulations constrained by velocity measurements demonstrated a significant (up to 30%) decrease of power available in the flow. A significant change in spatial pattern of power density distribution was also identified. It is demonstrated that by merging high resolution velocity measurements at tidal energy site with modeling the tidal stream potential estimation becomes more accurate.

Abstract Tidal circulation and tidal stream resource in Alderney Race (Raz Blanchard) were assessed by using a towed acoustic Doppler current profiler (ADCP) system and tidal modeling. Optimal Interpolation (OI) was applied to process the underway velocity measurements recorded at neap tide flood and ebb flow. The interpolation technique allows reconstructing space-time evolution of the velocity field within the domain during surveying periods. The method employs velocity covariances derived from numerical simulations by a 2D hydrodynamic model MARS. Model covariances are utilized by the OI algorithm to obtain the most likely evolution of the velocity field under the constraints provided by the ADCP observations and their error statistics. The resulting velocity fields were used for assessing the tidal stream resource at site. The largest overall difference between the kinetic power density derived from simulated and interpolated velocity fields was found for ebb tide. Model simulations constrained by velocity measurements demonstrated a significant (up to 30%) decrease of power available in the flow. A significant change in spatial pattern of power density distribution was also identified. It is demonstrated that by merging high resolution velocity measurements at tidal energy site with modeling the tidal stream potential estimation becomes more accurate.