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International audience; The building stock accounts for 43% of the total French final energy consumption in 2017. The French building stock mainly includes residential and tertiary buildings, which have very different consumption patterns. Today, building stock models are largely used in many countries for energy demand forecast and decision making. In this context, good knowledge of the building stock is essential for modeling. However, this type of model is lacking for the tertiary sector, as it is difficult to categorize buildings that have a wide variety of area and energy uses, different systems and complex dynamic trends. Existing stock models are mostly based on an aggregated representation of the total heated floor area of the building stock. Such a representation limits explicit studies of the factors affecting the energy demand and fails at taking into account heterogeneity. This paper exposes and discusses new methods aiming at modeling the tertiary building stock at the city scale in France. While mainly relying on open source public data, methods are designed to be applicable at any scale (from small cities to large region or even national scale). 1. Introduction For many years, building energy modeling and simulation have been largely used in advising decision makers in the domain of energy policy [1]. The building stock accounts for 43% of the total French final energy consumption in 2017 [2]. The tertiary sector is responsible for one third of the total building stock's consumption. Whereas considerable research has been devoted to the residential building stock, less attention has been paid to the tertiary building stock. Heterogeneity is the main reason that makes it difficult to study the tertiary sector. The representation of the tertiary building stock is usually based on the total heated floor area of economic sub-sectors, aggregated at national scale, omitting heterogeneity. Through this work, we develop a building stock model which allows a detailed description of this sector's building stock. The purpose of this model is to study the energy demand as well as long-term projections of the tertiary stock. Recently, detailed individual building and building stock models have begun to merge into hybrid methods that might help evaluating the energy demand of a group of buildings, which may contain from dozens to thousands individuals [3]. Our ambition is to represent the tertiary building stock as a group of individual buildings. The first important step is to determine the area of each building. Many building stock models use the area as a key variable for estimating the energy demand. For example in the econometric model NEMS-National Energy Modeling System, the US tertiary building stock is described in its Commercial Demand Module [4]. In NEMS, the floor area is used in many of

International audience

Thanks to their high theoretical efficiency, residential heat pumps (HP) are a promising technology when attempting to reduce the energy consumption of heating in dwellings. Evaluation of their real performances on-field is thus crucial to promote their development and deployment. However, measuring accurately real heating capacity of air-to-air HP is not easy, since measuring air enthalpy and mass flow rate is challenging. A previously developed non-intrusive internal method based on the compressor energy balance has been improved. It can calculate the coefficient of performance (COP) of different HP types, including air-to-air, on field, thanks to real-time measurements, without interfering with normal operation of the system, and without technical data of the specific heat pump. In this study, a complete validation of this method has been led on a test bench, using an air-to-water HP in order to compare the results of the method with the water-side measurements. This internal refrigerant method was tested for various climatic conditions and heating needs, in stationary and dynamic conditions, including starting and defrosting phases. Different faults were simulated to analyse the behaviour of the method in these conditions, including refrigerant undercharging and exchanger fouling. The analysis also extends to identifying which parameters need to be observed to early detect these faults. The method proves to be robust and its uncertainty to remain low, although it varies with the different working phases. The precise knowledge of real-time performances obtained with this method can help to assess the performance impact of faults and thus to improve associated fault detection and diagnostic methods. On a longer-term scale, the comparison of measured field performances and performances obtained via simplified models, such as regulatory models for instance, could give interesting indications to improve these models.

International audience; RÉSUMÉ. Les outils de simulation sont couramment employés pour évaluer la consommation énergétique d'un bâtiment. Lors du processus de modélisation, des choix doivent être réalisés par l'utilisateur de l'outil, tels que la division du bâtiment en zones thermiques. Le but de ce travail est d'évaluer l'influence du découpage en zones sur les résultats de la simulation thermique dynamique en incluant ou non les flux d'air et les transferts thermiques entre les zones. À cette fin, cinq découpages en zones (modèles de 49 à 11 zones) sont appliqués au même immeuble de bureau. L'impact de la fusion des étages est analysé en considérant différents isolants de plancher et toiture et celui de l'union des orientations est étudié à l'aide de différents taux de surface vitrée. Les résultats des simulations thermiques dynamiques sont comparés en termes de besoins énergétiques (chauffage et refroidissement) ainsi qu'en temps de calcul et de paramétrage du modèle.ABSTRACT. Simulation tools are widely used to assess the energy consumption of a building. In the modeling process, some choices should be made by the simulation tool user such as the division of the building into thermal zones. The aim of this work is to assess the influence of building zoning on the results of the dynamic thermal simulation including or not airflow and thermal transfers between zones. For this purpose, several different building zonings (49-zone to 11-zone models) are applied to the same office building. The impact of merging the floors is analyzed by considering different roof and floor insulations and the impact of merging the orientations is studied by using different glazed surface ratio. The results of the dynamic thermal simulations are compared in terms of energy demand (heating and cooling) and computational and setup times.

International audience; The decrease of heat demands in the low energy buildings requires to reexamine modeling approaches in the building simulation, particularly the dynamic response of the building and its equipments lead to re-examine modeling rules. From a review of air-to-air heat pump models, three types are compared in order to evaluate the ability of each one to predict the energy consumption and power demands. These air-to-air heat pump models coupled to a single zone building are simulated on Modelica. The aim is to underline the advantages and the drawbacks of the different modeling approaches for dynamicsimulationinrespectofthedifferentphenomena to represent.

Article accessible gratuitement en ligne à l'adresse http://aicvf.org/la-revue-cvc/n%C2%B0867-janvierfevrier-2011/; National audience; L'usage de la climatisation en Europe est aujourd'hui en très forte augmentation. À titre d'exemple, environ 3,5 millions de climatiseurs individuels ont été vendus en 2005 contre 1,6 million en 1996 (120 % d'augmentation en dix ans). L'existant n'échappe pas à cette tendance, l'isolation des bâtiments lors d'une réhabilitation thermique, nécessaire pour réduire les consommations de chauffage, peut notamment se traduire par des inconforts d'été détectés après coup et favoriser l'installation ultérieure de systèmes de rafraichissement mécanique.

International audience; The energy savings achievable in the end-use space cooling depend on a number of variables related to the building envelope, the plants and to some extent the behavior of occupants. They are hence complex to evaluate and consequently often underrepresented in designers, energy managers and policy makers decisions.This paper is based on some results of the European Commission supported project KeepCool2. It discusses a methodology for bottom-up assessment of the energy savings related to “sustainable summer comfort” solutions: to do this, reference base case building typologies in offices and commercial sector are analyzed in 5 european typical climates, and dynamic simulations are used to calculate the reductions in the energy needs for cooling which can be achieved by specific retrofit actions (e.g. additions of effective solar protections, increased thermal insulation, day-time and nighttime mechanical ventilation, natural ventilation, low solar absorbance surfaces and others); also thermal comfort conditions in the analysed base cases are evaluated by using Fanger model and Adaptive ones, according to the european standard EN15251. Conducted dynamic simulations also allow to evaluate the effects on energy consumptions of the interactions between several considered energy efficiency improvement action. By using the developed methodology, we show typical values of energy savings related to single or packaged technical measures of sustainable summer comfort applied to typical building, in typical european climates. The adoption of different types of shadowing devices and relative manual and automatic controls and the use of adequate ventilation strategies show great potential in energy savings for cooling.

ISSN : 0016-5328 Site web de l'éditeur: http://www.afgaz.fr/site/page-afg-428.html; Aujourd'hui, les infrastructures d'importation de gaz en Italie se résument à quatre gazoducs principaux et jusqu'à très récemment à un seul terminal méthanier sur le site de Panigaglia, dans la province de La Spezia. En octobre 2009 a eu lieu la mise en service d'un deuxième terminal, l'Adriatic LNG, à proximité de Porto Levante. Le ministère de l'Économie et du développement italien s'attend dans les prochaines années à une forte croissance de la consommation de gaz naturel, aujourd'hui principalement satisfaite par la Russie et l'Algérie. C'est pourquoi l'Italie doit construire d'importantes infrastructures pour faire face à cette demande. Une part significative de la demande devrait être prise en charge par les nouveaux terminaux de regazéification. État d'avancement des principaux projets de terminaux méthaniers en Italie.

ISBN : 978-2911762932; 2911762932; Les transferts thermiques font partie des Sciences de base de l'ingénieur et il existe peu de domaines industriels où la thermique ne joue un rôle petit ou grand. Au minimum, l'ingénieur doit donc en connaître les principes fondamentaux, être capable d'évaluer leur importance dans un problème particulier et dégager les ordres de grandeur par une modélisation simple. Ce livre est le cours de thermique tel qu'il est enseigné aux élèves ingénieurs de l'Ecole des Mines de Paris. Sans prétendre à l'exhaustivité d'un manuel de référence, qui serait plus particulièrement dédié aux ingénieurs thermiciens, ce cours résume de manière claire et condensée les notions principales de la thermique. Ses deux principaux objectifs sont : • de faire comprendre les phénomènes physiques mis en jeu dans les échanges énergétiques : conduction, rayonnement, convection • de savoir mettre en œuvre des méthodes appropriées pour appréhender le dimensionnement et le fonctionnement de dispositifs énergétiques. Le premier chapitre de ce cours est harmonisé avec le cours de Thermodynamique également publié aux Presses de l'Ecole des Mines.