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L’efficacité économique du secteur électrique indien
No full textIndia’s power sector has seen three waves of reform: 1991 liberalization, 2003 unbundling of state utilities, and, since 2011, large-scale renewable procurement via the Solar Energy Corporation of India (SECI). SECI’s flagship mechanism awards 25-year, flat-tariff PPAs through two-stage auctions: a sealed‐bid qualification round followed by an open descending‐clock, uniform-price final stage.The first chapter theoretically studies certain non-trivial elements of the auctions for large-scale procurement of capacity of renewable electricity production in India. The auctions, designed by SECI, award power purchase agreements (PPAs) to independent power producers (IPPs). These agreements mention the capacity (in Mega Watts) to be created by a particular IPP and the tariff paid to them per KiloWatt-Hour of power they produce, both determined through an auction. The chapter provides the details of the allocation mechanism. Thereafter, I characterise the semi-separating Bayes Nash equilibrium of an abstraction of this auction, to study the impact of a particular allocation rule, which has so far been studied only with symmetric firms. The rule results in a multi-winner open-bid uniform price auction of a large divisible good, with bidders having asymmetric demand for that good. The equilibrium in this asymmetric setting is such that this auction inadvertently provides larger contracts are awarded to higher cost firms. Therefore,the market designed by these auctions is cost-inefficient.The second chapter builds on theoretical results of the first chapter, empirically measuring the inefficiency of India’s renewable energy auctions, as well as proposing design improvements. To this end, I structurally estimate parametric cost distributions of firms, using bid data from the Solar Energy Corporation of India (SECI) and firm information from various sources. For the estimation, I use tariff offers of the bidders who got an award of zero whose dominant strategy is to bid their cost. However, owing to some qualification rules, this set of bidders is self-selected over a threshold endogenous to their cost draws due to some qualification rules. I first show that we can identify the cost distribution despite the self-selection as long as there are at least 2 zero award bidders in any auction. Thereafter, I estimate the distribution using a partial information maximum likelihood estimator. Finally, I provide a counterfactual analysis, where we can see that that the current allocation method has a 40% probability of adverse selection and has 5% lower payoff to SECI compared to the VCG mechanism.The third chapter shifts focus to the fossil fuel-based "brown" electricity sector in India, which is dominated by coal and gas-powered thermal plants. As we saw earlier, these plants account for a significant portion of India’s power production and coal consumption and will continue to play a crucial role in grid stabilization as renewable power is integrated. Since the market evolution of this subsector is different from green power sector, and auctions have not been its primary shaper, I use a different measure for efficiency, the Total Factor Productivity (TFP). The firm level estimates of TFP have direct implication for cost-efficiency. A firm with higher TFP can produce more with the same level of inputs and thus has a lower average cost of production.Overall, the thesis shows that India's power sector has inefficiencies. While the cost inefficiency for the renewable sector is an inadvertent effect of market design policy, which can be rectified, the brown sector's inefficiency may be due to legacy issues. As both sectors continue to play a dominant role in India's economy, the thesis provides important policy implications for the future.Le secteur électrique indien a connu trois vagues de réformes : la libéralisation de 1991, la scission (« unbundling ») des services publics d’État en 2003 et, depuis 2011, l’approvisionnement à grande échelle en énergies renouvelables via la Solar Energy Corporation of India (SECI). Le mécanisme phare de la SECI attribue des Power Purchase Agreements (PPA) de 25 ans à tarif fixe par le biais d’enchères en deux étapes : une phase de qualification par offres scellées, suivie d’une phase finale ouverte à horloge descendante et prix uniforme. Le premier chapitre étudie théoriquement certains éléments non triviaux de ces enchères destinées à l’acquisition de capacité de production d’électricité renouvelable à grande échelle en Inde. Conçues par la SECI, elles attribuent des PPA à des producteurs indépendants (IPP), précisant la capacité (en mégawatts) à installer et le tarif par kilowattheure qui leur sera versé, tous deux déterminés aux enchères. Le chapitre détaille le mécanisme d’allocation, puis caractérise l’équilibre de Bayes-Nash semi-séparateur d’une abstraction de ce dispositif, afin d’analyser l’impact d’une règle d’attribution étudiée jusqu’ici uniquement pour des entreprises symétriques. Cette règle donne lieu à une enchère ouverte, multi-gagnants et à prix uniforme, pour un bien divisible de grande ampleur, où les enchérisseurs ont des demandes asymétriques. L’équilibre montre qu’elle conduit involontairement à attribuer des contrats plus importants à des entreprises dont le coût est plus élevé : le mécanisme est donc inefficace en termes de coût. Le deuxième chapitre s’appuie sur ces résultats théoriques pour mesurer empiriquement l’inefficience des enchères de la SECI et proposer des améliorations de conception. Pour ce faire, j’estime structurellement des distributions de coûts paramétriques à partir des données d’enchères de la SECI (2016–2023) et d’informations sur les entreprises. J’utilise pour l’estimation les offres tarifaires des enchérisseurs ayant reçu une attribution nulle, dont la stratégie dominante est de proposer leur coût réel. Or, en raison de certaines règles de qualification, cet ensemble est auto-sélectionné selon un seuil endogène lié à leur tirage de coûts. Je montre d’abord que la distribution des coûts reste identifiable dès lors qu’au moins deux enchérisseurs zéro-attribution participent à chaque enchère. J’estime ensuite cette distribution par un estimateur du maximum de vraisemblance à information partielle. Enfin, une analyse contrefactuelle révèle que la méthode actuelle a une probabilité de 40 % de sélection adverse et procure à la SECI un rendement inférieur de 5 % par rapport à un mécanisme de type VCG. Le troisième chapitre se concentre sur le secteur de l’électricité « brun » à base de combustibles fossiles, dominé par les centrales thermiques au charbon et au gaz. Comme on l’a vu, ces centrales représentent une part importante de la production et de la consommation de charbon en Inde et demeurent essentielles à la stabilité du réseau lors de l’intégration des renouvelables. N’ayant pas été façonné par des enchères, ce sous-secteur requiert une mesure d’efficience différente : la productivité totale des facteurs (PTF). Les estimations de la PTF au niveau des entreprises—obtenues par MCO et la méthode de Levinsohn–Petrin—montrent que les grands acteurs, et même certaines sociétés détentrices de contrats renouvelables, présentent une PTF plus faible, traduisant des inefficiences de taille et de diversification. Dans l’ensemble, la thèse met en évidence les inefficiences du secteur électrique indien : celle des enchères renouvelables résulte d’un effet involontaire de la conception du marché et peut être corrigée, tandis que celle du secteur brun est probablement due à des problématiques historiques. Étant donné le rôle majeur de ces deux segments dans l’économie indienne, ces résultats offrent d’importantes pistes de politique publique pour l’avenir
La rivière et son réseau.: La participation numérique citoyenne, de l’alerte à la mobilisation environnementale
No full textNational audienceLa rivière et son réseau.La participation numérique citoyenne, de l’alerte à la mobilisation environnementale
Gender norms and partners' joint retirement decisions: learning from a Norwegian reform
No full textWe argue that gender norms may shape partners' joint retirement decision. We study a 2011 pension reform in Norway, which incentivized postponing retirement for employees of many private sector firms. Using Norwegian register data, we construct population samples of older dual-earner couples in which only one partner was eligible for the reform, and link them to their mothers' employment status when partners were young, to capture gender norms. Taking an event-study differences-in-differences approach, we find significant employment effects for the partner directly affected by the reform, and heterogeneous spillover effects for the other partner. In particular, women with an employed mother-in-law, but not those with a stay-home mother-inlaw, increase their employment, if their husband does so, due to the reform. In contrast, men with a stay-at-home mother are more likely to postpone retirement if their wife does so, following the reform
Data-based estimates of ocean carbon uptake biased high from neglect of submonthly atmospheric pressure variability
No full textCurrent estimates of the global ocean carbon sink based on measurements of CO2 fugacity are inconsistent with those obtained from global ocean biogeochemistry models. Here we investigate how this gap might be partially closed by more fully accounting for submonthly variability in observation-based estimates. While these estimates compute the air-sea CO2 flux based on hourly wind speed, other variables have only monthly resolution. Thus they neglect some high-frequency variability from short-term events such as storms. To evaluate this error, we compare fluxes at different temporal resolutions between 2009 and 2018. We find that accounting for hourly variations in atmospheric pressure and daily variations in sea surface temperature decreases the global carbon uptake estimate by 5% (0.12 Pg C yr-1) which is driven by the submonthly covariance between wind speed and atmospheric pressure, particularly in the southern extratropics. This represents 25% of the average gap between observationbased and model estimates
On the Development of a Self-Sealing Experimental Setup for Natural Claystones Considered as Potential Host Rocks for Radioactive Waste Disposal: Application to the Sandy Opalinus Clay
No full textInternational audienceA new experimental device allowing the follow-up of the self-sealing of damaged claystone has been developed. This device consists of a constant volume cell with a displacement transducer tracking the closure of the artificially created diametric fracture. Two additional sensors were installed to obtain additional information: a total pressure sensor monitoring the radial swelling pressure and a mini-pressure sensor inserted within the diametric fracture that measure the pressure changes during the sealing process. To simulate in situ conditions, a series of three small-scale mock-up tests were performed on artificially fractured Opalinus Clay samples from the lower sandy facies of the Mont Terri site. The solutions used were synthetic water with the same salt concentration and pH as the natural neutral pore water, a sodium nitrate (NaNO3) saline solution, and an alkaline solution. Results showed that the end frictions, identified from the evolution of the radial swelling pressure, together with the mini-pressure sensor, control the fracture closing. The mini-pressure sensor that was installed in the first test immediately fell out of service because of hydration, and the radial swelling pressure was affected by the rigid-rigid contact between the sample and the total pressure sensor. This series of tests revealed the key points related to the designed cell for further improvement. In the second design, a cavity to house the mini-pressure sensor was engraved on the facet of one of the two half-samples, and the preparation of this sensor was improved to ensure its water tightness. A cylindrical wedge was fabricated to avoid the rigid-rigid contact. A second series of tests with the same three solutions and the same material were then conducted. This series has been running for 270 days and its results are more satisfactory
A New Prognostic Parameterization of Subgrid Ice Supersaturation and Cirrus Clouds in the ICOLMDZ AGCM
No full textInternational audienceA new cirrus cloud parameterization for the ICOLMDZ atmospheric general circulation model (AGCM) is presented. Prognostic equations for cloud fraction, ice water content and cloudy water vapor are introduced, and the processes that affect these quantities are parameterized. In particular, the tendency in ice crystal mass concentration due to changes in water phases is calculated, as is the macroscale mixing of cirrus clouds with their environment. The parameterization simulates ice supersaturation in clear sky, an ubiquitous metastable phenomenon in the upper troposphere that is necessary for the formation of in situ cirrus clouds. Our parameterization also allows for cirrus clouds to be sub-and supersaturated with respect to ice. It is evaluated on a case study of a warm conveyor belt cirrus cloud forming and dissipating above the Paris region. The representation of high cloud cover is improved with the new parameterization relative to the default version of the cloud scheme in comparison to observations, as is the representation of water vapor. In particular, the upper tropospheric dry bias from ICOLMDZ is corrected, although it is replaced by a wet bias in some cases. Global simulations show similar results. Contrarily to the default parameterization, ice water content and high cloud cover can be tuned separately, but the ice fall velocity parameter, that controls the intensity of ice autoconversion, remains the most determining parameter controlling the overall ice water content.</div
Faire des villes des lieux à soi féminins : complémentarité des parcours virtuels et physiques du matrimoine du programme « Cité des Dames, créatrices dans la Cité »
No full textNational audienceThe “Cité des dames, women creators in the city” research project aims to highlight the contribution of women to the making of cities, notably by women’s heritage walks and mapping itineraries drawn from women’s texts. These routes, which can be followed on site or on digital applications, give special prominence to texts by women writers and to resources that help to read them. The restitution of the links between these texts and urban spaces is part of a cultural tourism approach that renews the way we look at cities.Le projet de recherche « Cité des dames, créatrices dans la cité » vise à mettre en valeur la contribution des femmes à la fabrique des villes, notamment en créant des promenades du matrimoine et des cartographies d’itinéraires tirés de textes de femmes. Ces parcours, que l’on peut effectuer sur place ou sur des applications numériques, accordent une place particulière aux textes d’autrices et aux ressources qui aident à les lire. La restitution des liens entre ces textes et les espaces urbains s’intègre ainsi dans une démarche de tourisme culturel qui renouvelle le regard sur les villes
Planning and Evaluating NATure-Based Solutions within local authoritiEs – the PENATE project
No full textInternational audienceThis poster aims to present the French ANR PENATE project, which has just started. PENATE seeks to evaluate the performance and effectiveness of Nature-Based Solutions (NbS) as a strategy for adapting urban environments to climate change. To this end, it aims to develop multi-scale, multi- criteria, context-sensitive, and adaptive evaluation tools and methods tailored for local authorities.The project is supported by a multidisciplinary consortium, bringing together expertise in hydrology, microclimatology, ecology, public policy, and law, and involving both research organizations and operational stakeholders. It includes several pilot sites where NbS are currently under monitoring. The project addresses key challenges such as mitigating urban heat islands, managing stormwater and flooding, improving quality of life, and ensuring ecological continuity across territories.To achieve these objectives, PENATE aims to:- Analyze and understand the legal, institutional, and technical constraints tied to implementing regulatory and strategic frameworks, and explore how NbS can address these challenges.- Link the intrinsic properties of vegetation with their effects on thermo-hydraulic processes in NbS infrastructure through a functional traits-based approach.- Develop digital tools capable of simulating the multifunctionality of NbS and evaluating their performance across different scales within complex territories.The outcomes of PENATE are designed to support the integration of NbS into regulatory frameworks such as Local Urban Development Plans (PLUi), Climate Air Energy Plans (PCAET), and the Zero Net Artificialization (ZAN) objective. The project will provide local authorities with a dedicated diagnostic and decision-support tool to guide land-use planning and facilitate the implementation of NbS
Quels facteurs expliquent des différentiels d'attractivité entre lignes de desserte fine du territoire ? Une analyse à partir des potentiels compatibles
No full textInternational audienceLes lignes de desserte fine du territoire constituent une proportion du réseau TER actuel qui est loin d'être négligeable. Les fréquences y sont relativement faibles, comparées aux réseaux limitrophes, et le positionnement horaire des circulations répond parfois moins aux attentes des populations riveraines qu'à des contraintes liées à l'infrastructure, dont la capacité est dimensionnante. Au-delà de solutions d'ordre purement technique visant à alléger les coûts d'exploitation sans nuire à la fréquence se pose la question de la pertinence de l'offre et de son attractivité dans des contextes où la circulation automobile demeure fluide.Nos investigations antérieures pour le compte de la région Normandie (Mimeur et al. 2021 ; Zembri 2022), puis dans le cadre du projet TELLI (Tu-Thi et al. 2024), ont mis en évidence l'écart pouvant exister entre le potentiel compatible avec le ferroviaire (POCO) et la réalité des trafics mesurés sur les lignes concernées.Cet écart n'est cependant pas constant entre les différentes lignes analysées. Par exemple, parmi l'ensemble des origines-destinations compatibles avec le transport ferroviaire, seulement 23 % des navetteurs optent pour les transports en commun comme mode de transport principal sur la ligne Rennes-Châteaubriant. Ce taux chute à 6 % pour la ligne Saumur-La Roche-sur-Yon et à 8 % pour l'Étoile ferroviaire de Saint-Pol-sur-Ternoise, des résultats très faibles qui concernent deux lignes aux niveaux de service très différents. En termes de trafic, plusieurs questions se posent. Pourquoi les voyageurs n'ont-ils pas choisi le train ? Cela est-t-il uniquement dû à la qualité du service proposé ? Si tel est le cas, une augmentation de la fréquence entraînerait-elle un report de la demande des automobilistes vers le train ? Afin de répondre à ces questions, nous proposons une méthode visant à identifier les facteurs déterminants de la transformation du potentiel compatible en usages effectifs. Cette approche fournit ainsi des leviers d'action aux décideurs publics pour capter certains trafics vers le train