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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Retrofitting a high-rise residential building to reduce energy use by a factor of 10

Richards, Christopher John 30 April 2007 (has links)
This thesis details the ways in which energy is consumed in an existing Canadian high-rise apartment building and outlines a strategy to reduce its consumption of grid purchased energy by 90%. Grid purchased energy is targeted because the building is located in Saskatchewan where energy is predominantly generated from fossil fuels that release greenhouse gas emissions into the environment. Greenhouse gas emissions are targeted because of the growing consensus that human activities are the cause of recent global climate destabilization and the general trend towards global warming. Energy consumption is also a concern because of anticipated resource shortages resulting from increases in both global population and average per capita consumption. Many researchers are beginning to claim that a factor 10 reduction in energy use by industrialized nations will be required in order for our civilization to be sustainable.<p>The building that was studied is an 11 story seniors high-rise with a total above ground floor area of 8,351 m2. It was constructed in 1985, in Saskatoon, SK, and it is an average user of energy for this region of the world and for a building of its size and type. Numerous field measurements were taken in the building, both during this study and previously by the Saskatchewan Research Council. These measurements were used to create a computer model of the building using EE4. After the computer model of the building was created different energy saving retrofits were simulated and compared. <p>Over 40 retrofits are presented and together they reduce the annual grid purchased energy of the building from 360 kWh/m2 (based on above ground floor area) to 36 kWh/m2, a factor 10 reduction. Natural gas consumption was reduced by approximately 94% and grid purchased electrical consumption was reduced by approximately 81%. As a result of these energy savings, a factor 6.6 reduction (85%) in greenhouse gas emissions was also achieved. The goal of factor 10 could not be achieved only through energy conservation and the final design includes two solar water heating systems and grid-connected photovoltaic panels. These systems were modeled using RETScreen project analysis tools.<p>Capital cost estimates and simple payback periods for each retrofit are also presented. The total cost to retrofit the building is estimated to be $3,123,000 and the resulting utility savings from the retrofits are approximately $150,000 per year. This is a factor 6.0 reduction (83%) in annual utility costs in comparison to the base building. While the typical response to proposing a green building is that financial sacrifices are required, there is also research available stating that operating in a more sustainable manner is economically advantageous. This research project adds to the green building economics debate by detailing savings and costs for each retrofit and ranking each retrofit that was proposed. The most economically advantageous mechanical system that was added to the building was energy recovery in the outdoor ventilation air. It should also be noted that there was already a glycol run-around heat recovery system in the building and even greater savings would have been obtained from installing the energy recovery system had this not been the case.<p>While the goal of factor 10 required economically unjustifiable retrofits to be proposed, the majority of the retrofits had simple payback periods of less than 20 years (30 out of 49). This research shows that certain retrofits have highly desirable rates of return and that when making decisions regarding investing in auditing a building, improving energy efficiency, promoting conservation, or utilizing renewable energy technologies, maintaining the status quo may be economically detrimental. This would be especially true in the case of new building construction.
152

Management of building energy consumption and energy supply network on campus scale

Lee, Sang Hoon 19 January 2012 (has links)
Building portfolio management on campus and metropolitan scale involves decisions about energy retrofits, energy resource pooling, and investments in shared energy systems, such as district cooling, community PV and wind power, CHP systems, geothermal systems etc. There are currently no tools that help a portfolio/campus manager make these decisions by rapid comparison of variants. The research has developed an energy supply network management tool at the campus scale. The underlying network energy performance (NEP) model uses (1) an existing energy performance toolkit to quantify the energy performance of building energy consumers on hourly basis, and (2) added modules to calculate hourly average energy generation from a wide variety of energy supply systems. The NEP model supports macro decisions at the generation side (decisions about adding or retrofitting campus wide systems) and consumption side (planning of new building design and retrofit measures). It allows testing different supply topologies by inspecting which consumer nodes should connect to which local suppliers and to which global suppliers, i.e. the electricity and gas utility grids. A prototype software implementation allows a portfolio or campus manager to define the demand and supply nodes on campus scale and manipulate the connections between them through a graphical interface. The NEP model maintains the network topology which is represented by a directed graph with the supply and demand nodes as vertices and their connections as arcs. Every change in the graph automatically triggers an update of the energy generation and consumption pattern, the results of which are shown on campus wide energy performance dashboards. The dissertation shows how the NEP model supports decision making with respect to large-scale building energy system design with a case study of the Georgia Tech campus evaluating the following three assertions: 1. The normative calculations at the individual building scale are accurate enough to support the network energy performance analysis 2. The NEP model supports the study of the tradeoffs between local building retrofits and campus wide energy interventions in renewable systems, under different circumstances 3. The NEP approach is a viable basis for routine campus asset management policies.
153

Development of a commercial building/site evaluation framework for minimizing energy consumption and greenhouse gas emissions of transportation and building systems

Weigel, Brent Anthony 17 May 2012 (has links)
In urbanized areas, building and transportation systems generally comprise the majority of greenhouse gas (GHG) emissions and energy consumption. Realization of global environmental sustainability depends upon efficiency improvements of building and transportation systems in the built environment. The selection of efficient buildings and locations can help to improve the efficient utilization of transportation and building systems. Green building design and rating frameworks provide some guidance and incentive for the development of more efficient building and transportation systems. However, current frameworks are based primarily on prescriptive, component standards, rather than performance-based, whole-building evaluations. This research develops a commercial building/site evaluation framework for the minimization of GHG emissions and energy consumption of transportation and building systems through building/site selection. The framework examines, under uncertainty, multiple dimensions of building/site operation efficiencies: transportation access to/from a building site; heating, ventilation, air conditioning, and domestic hot water; interior and exterior lighting; occupant conveyances; and energy supply. With respect to transportation systems, the framework leverages regional travel demand model data to estimate the activity associated with home-based work and non-home-based work trips. A Monte Carlo simulation approach is used to quantify the dispersion in the estimated trip distances, travel times, and mode choice. The travel activity estimates are linked with a variety of existing calculation resources for quantifying energy consumption and GHG emissions. With respect to building systems, the framework utilizes a building energy simulation approach to estimate energy consumption and GHG emissions. The building system calculation procedures include a sensitivity analysis and Monte Carlo analysis to account for the impacts of input parameter uncertainty on estimated building performance. The framework incorporates a life cycle approach to performance evaluation, thereby incorporating functional units of building/site performance (e.g energy use intensity). The evaluation framework is applied to four case studies of commercial office development in the Atlanta, GA metropolitan region that represent a potential range of building/site alternatives for a 100-employee firm in an urbanized area. The research results indicate that whole-building energy and GHG emissions are sensitive to building/site location, and that site-related transportation is the major determinant of performance. The framework and findings may be used to support the development of quantitative performance evaluations for building/site selection in green building rating systems and other efficiency incentive programs designed to encourage more efficient utilization and development of the built environment.
154

Μελέτη ενεργειακών υλικών και ήπιων μεθόδων δροσισμού κτιρίων για την αντιμετώπιση του φαινομένου των αστικών θερμικών νησίδων και την εξοικονόμηση ενέργειας

Βαρδουλάκης, Ευτύχιος 26 August 2014 (has links)
Στα πλαίσια της έλλειψης της μελέτης του φαινομένου της ΑΘΝ σε περιφερειακές Ελληνικές πόλεις, η παρούσα διδακτορική διατριβή παρουσιάζει και αναλύει τα αποτελέσματα της μελέτης του φαινομένου της ΑΘΝ σε δύο μικρές πόλεις της περιφέρειας, το Αγρίνιο και τα Ιωάννινα. Στόχος της εργασίας είναι να μελετήσει την ύπαρξη της ΑΘΝ, καθώς και να προσδιορίσει την ένταση και τη μορφή της. Για το σκοπό αυτό ένα δίκτυο αισθητήρων θερμοκρασίας σε συνδυασμό με μετεωρολογικούς σταθμούς αναπτύχθηκε στις δύο πόλεις και θερμοκρασιακά δεδομένα συλλέχθηκαν για το σχηματισμό του θερμικού τους προφίλ. Τα αποτελέσματα δείχνουν έντονη παρουσία του φαινομένου κυρίως κατά τις βραδινές ώρες και ένταση θερμικής νησίδας που φτάνει και τη μέση τιμή των 3.8 οC το μήνα Αύγουστο στο Αγρίνιο ενώ στα Ιωάννινα για την ίδια περίοδο το φαινόμενο έχει πιο ήπια μορφή (1.5 οC). Για την αντιμετώπιση του φαινομένου, την εξοικονόμηση ενέργειας καθώς και τη βελτίωση της θερμικής άνεσης των κτιρίων πόλεων που αντιμετωπίζουν πρόβλημα με την ΑΘΝ, μελετήθηκε η περίπτωση χρήσης υδρόφιλων ενεργειακών υλικών ως επικάλυψη οροφών, για μείωση της ροής θερμότητας από την οροφή με εξατμιστικό δροσισμό καθώς και τα δευτερεύοντα ενεργειακά κέρδη από μια πιθανή εγκατάσταση φωτοβολταϊκών οροφής. Η μελέτη περιλάμβανε την ανάπτυξη πειραματικής διάταξης αεροσήραγγας για τη δοκιμή των υλικών, με προσομοίωση των καιρικών συνθηκών της πόλης κατά του καλοκαιρινούς μήνες, όπου και το φαινόμενο της αστικής θερμικής νησίδας είναι πολύ έντονο, καθώς και ανάπτυξη φωτοβολταϊκών σε ταράτσα πανεπιστημιακού κτιρίου. Τα αποτελέσματα δείχνουν ότι ο εξατμιστικός δροσισμός μπορεί να αποτελέσει μια πολλά υποσχόμενη μέθοδο για την αντιμετώπιση της ΑΘΝ, ενώ η εγκατάσταση φωτοβολταϊκών μπορεί να συνεισφέρει επίσης στην εξοικονόμηση ενέργειας για δροσισμό τους καλοκαιρινούς μήνες, επιπλέον της παραγωγής ενέργειας. / Due to the lack of research on the field of the UHI effect in minor Greek cities, this thesis presents and analyzes the results of studying the UHI phenomenon in two small cities of the Greek province, Agrinio and Ioannina. Our aim was to study the existence of the UHI phenomenon as well as to determine its intensity and its type. In order to achieve that, a network of thermal sensors and meteorological stations was set on the two cities and temperature data were collected in order to define their thermal profile. The results point severe presence of the phenomenon especially during the nocturnal hours while the intensity of the phenomenon reaches up to 3.8 οC during August in Agrinio while in Ioannina at the same period the phenomenon is softer (1.5 οC). To mitigate the problem, save energy and improve the thermal capacity of the urban buildings in cities where the UHI occurs, the use of hydrophilic materials as a layer sheathing the roof was developed, in order to control the thermal flow from the roof by evaporative cooling. Furthermore, secondary energy benefits from a possible photovoltaics roof installation were investigated. Our research included the developing of an experimental set-up of a wind tunnel where sample materials were tested, by simulating the weather conditions of the city during the summer months, exactly the period of the high UHI intensity, as well as the installation of photovoltaics on a terrace of the university. The results indicate that evaporative cooling might be a very promising method in the field of the UHI phenomenon confrontation while the installation of photovoltaics can contribute in power saving for cooling during the summer months, in addition to electricity production.
155

Technical solutions for low-temperature heat emission in buildings

Ploskic, Adnan January 2013 (has links)
The European Union is planning to greatly decrease energy consumption during the coming decades. The ultimate goal is to create sustainable communities that are energy neutral. One way of achieving this challenging goal may be to use efficient hydronic (water-based) heating systems supported by heat pumps. The main objective of the research reported in this work was to improve the thermal performance of wall-mounted hydronic space heaters (radiators). By improving the thermal efficiency of the radiators, their operating temperatures can be lowered without decreasing their thermal outputs. This would significantly improve efficiency of the heat pumps, and thereby most probably also reduce the emissions of greenhouse gases. Thus, by improving the efficiency of radiators, energy sustainability of our society would also increase. The objective was also to investigate how much the temperature of the supply water to the radiators could be lowered without decreasing human thermal comfort. Both numerical and analytical modeling was used to map and improve the thermal efficiency of the analyzed radiator system. Analyses have shown that it is possible to cover space heat losses at low outdoor temperatures with the proposed heating-ventilation systems using low-temperature supplies. The proposed systems were able to give the same heat output as conventional radiator systems but at considerably lower supply water temperature. Accordingly, the heat pump efficiency in the proposed systems was in the same proportion higher than in conventional radiator systems. The human thermal comfort could also be maintained at acceptable level at low-temperature supplies with the proposed systems. In order to avoid possible draught discomfort in spaces served by these systems, it was suggested to direct the pre-heated ventilation air towards cold glazed areas. By doing so the draught discomfort could be efficiently neutralized.     Results presented in this work clearly highlight the advantage of forced convection and high temperature gradients inside and alongside radiators - especially for low-temperature supplies. Thus by a proper combination of incoming air supply and existing radiators a significant decrease in supply water temperature could be achieved without decreasing the thermal output from the system. This was confirmed in several studies in this work. It was also shown that existing radiator systems could successfully be combined with efficient air heaters. This also allowed a considerable reduction in supply water temperature without lowering the heat output of the systems. Thus, by employing the proposed methods, a significant improvement of thermal efficiency of existing radiator systems could be accomplished. A wider use of such combined systems in our society would reduce the distribution heat losses from district heating networks, improve heat pump efficiency and thereby most probably also lower carbon dioxide emissions. / <p>QC 20131029</p>
156

Information Technology & Sustainability: An Empirical Study of the Value of the Building Automation System

Simmonds, Daphne Marie 16 September 2015 (has links)
This study examines the environmental and economic effects of green information technology (IT). Green IT describes two sets of IT innovations: one set includes innovations that are implemented to reduce the environmental impact of IT services in organizations; and the other IT to reduce the environmental impact of other organizational processes. The two sets respond to the call for more environmentally friendly or “greener” organizational processes. I developed and tested a preliminary model. The model applied the resource based view (RBV) of the firm (Wernerfelt 1984) the stakeholder theory (Freeman 1984) and included four constructs: (1) BAS implementation; environmental value conceived in a novel way as the conservation of electric energy in buildings; economic value -- from energy cost savings; and BAS complements. These four constructs formed three propositions: (1) BAS implementation is positively associated with environmental value; (2) environmental value is positively associated with economic value; and BAS complements moderate the relationship BAS implementation and environmental value. The model was used to guide the investigation of three research questions: 1. What are the environmental and economic values of green IT? 2. How do green IT create the above values? 3. Are other dimensions of value created? If so, what are they? The focal IT investigated was the building automation system – a system designed to conserve electric energy and decrease operational costs. The unit of analysis of the study was the facilities management team – the implementers of the system. I collected data on a sample of six diverse cases of BAS implementations. The cases were diverse in terms of the BAS types, the building purposes, the building locations and the building occupancy and management. Two types of BAS were involved in the study, each with a different level of artificial intelligence: the more intelligent BAS self-reconfigured when changes in setpoints, for example, were necessary; the less intelligent BAS must be reconfigured by an engineer in similar circumstances. There was also diversity in terms of the buildings in which the systems were implemented and the occupancy and management of the buildings. The buildings include: the corporate headquarters of a global telecommunications firm; university classrooms; a residence hall in a university; and three multi-tenanted office complexes. The building occupancy and management differ in that some buildings are owner-occupied and are managed in-house, while the others are leased and their management outsourced. Data collection involved recorded semi-structured interviews of three sets of users in the organizations: building engineers; chief engineers; and property/facilities managers. The interviews were prearranged and were conducted onsite using an interview protocol. Each interview lasted approximately one hour and was conducted in one session. The data were transcribed and analyzed in Nvivo 10. The findings showed support for the presence of the four constructs within the preliminary model as well as for the three propositions in the preliminary model. The data also revealed contextual details of the BAS implementation and BAS complements constructs. There were also new dimensions value including: unanticipated types of economic value (including savings from reduced labor demand; social value (comfort and safety for building occupants); and strategic value (knowledge used to position the organizations for greater efficiency and effectiveness). Overall, the value outcomes of the implementations can be summarized as short term social, environmental and economic value as well as strategic value – consistent with the concept of sustainable value defined by Hart et al. (1995). Also, consistent with Zuboff’s (1985) description of the duality of intelligent IT systems -- the ability to informate and automate, the BAS implementation construct was found to include two distinct sources of value: equipment automation; and equipment information. The unanticipated value dimensions and types, as well as the sources of value were used to refine the research model. The study therefore a preliminary theoretical model – the resource based view of the sustainable organization (RBV-SO) -- as well as contextual implementation details that can be used to guide future investigations of the value created by intelligent green IT systems such as the BAS, as well as measurement items that can be used to inform quantitative studies of these systems. The study also adds to the practical body of knowledge concerning green IT implementations in general and implementations of the BAS in particular, concerning: details of the information value – for example, for measuring the environmental impact of the system and for substantiating claims in the application for green funds available to organizations; and details of some key complementary resources that enhance value creation within the context. Two major limitations of this study are: (1) a single coder was used in the analysis process and therefore no inter-coder reliability was established for the results; and (2) user perceptions rather than actual quantities were used to validate the findings. Some future research prospects include: use of these findings to conduct a quantitative study of an intelligent system extended with, for example, investigation of the impact of external forces such as government regulations, environmental issue salience, and market forces on the value created by green IT (such as the BAS); and investigation of the impact over time of the development of the strategic capabilities enabled by the BAS on creation of value.
157

Impacts of Climate Change on US Commercial and Residential Building Energy Demand

January 2016 (has links)
abstract: Energy consumption in buildings, accounting for 41% of 2010 primary energy consumption in the United States (US), is particularly vulnerable to climate change due to the direct relationship between space heating/cooling and temperature. Past studies have assessed the impact of climate change on long-term mean and/or peak energy demands. However, these studies usually neglected spatial variations in the “balance point” temperature, population distribution effects, air-conditioner (AC) saturation, and the extremes at smaller spatiotemporal scales, making the implications of local-scale vulnerability incomplete. Here I develop empirical relationships between building energy consumption and temperature to explore the impact of climate change on long-term mean and extremes of energy demand, and test the sensitivity of these impacts to various factors. I find increases in summertime electricity demand exceeding 50% and decreases in wintertime non-electric energy demand of more than 40% in some states by the end of the century. The occurrence of the most extreme (appearing once-per-56-years) electricity demand increases more than 2600 fold, while the occurrence of the once per year extreme events increases more than 70 fold by the end of this century. If the changes in population and AC saturation are also accounted for, the impact of climate change on building energy demand will be exacerbated. Using the individual building energy simulation approach, I also estimate the impact of climate change to different building types at over 900 US locations. Large increases in building energy consumption are found in the summer, especially during the daytime (e.g., >100% increase for warehouses, 5-6 pm). Large variation of impact is also found within climate zones, suggesting a potential bias when estimating climate-zone scale changes with a small number of representative locations. As a result of climate change, the building energy expenditures increase in some states (as much as $3 billion/year) while in others, costs decline (as much as $1.4 billion/year). Integrated across the contiguous US, these variations result in a net savings of roughly $4.7 billion/year. However, this must be weighed against the cost (exceeding $19 billion) of adding electricity generation capacity in order to maintain the electricity grid’s reliability in summer. / Dissertation/Thesis / Doctoral Dissertation Environmental Social Science 2016
158

The net zero-energy home: Precedent and catalyst for local performance-based architecture

January 2014 (has links)
abstract: The building sector is responsible for consuming the largest proportional share of global material and energy resources. Some observers assert that buildings are the problem and the solution to climate change. It appears that in the United States a coherent national energy policy to encourage rapid building performance improvements is not imminent. In this environment, where many climate and ecological scientists believe we are running out of time to reverse the effects of anthropogenic climate change, a local grass-roots effort to create demonstration net zero-energy buildings (ZEB) appears necessary. This paper documents the process of designing a ZEB in a community with no existing documented ZEB precedent. The project will establish a framework for collecting design, performance, and financial data for use by architects, building scientists, and the community at large. This type of information may prove critical in order to foster a near-term local demand for net zero-energy buildings. / Dissertation/Thesis / Appendix M - Simulation and Weather Data / M.S. Built Environment 2014
159

Impacts des enveloppes végétales à l’interface bâtiment microclimat urbain / Impacts of green envelopes at the interface between buildings and urban microclimate

Djedjig, Rabah 11 December 2013 (has links)
Cette étude s’inscrit dans le cadre du projet "ANR-Villes Durables VegDUD : Rôle du végétal dans le développement urbain durable ; une approche par les enjeux liés à la climatologie, l’hydrologie, la maîtrise de l’énergie et les ambiances" (2010-2013). Elle traite de la modélisation et de l’expérimentation de toitures et de façades végétales, en vue de l’évaluation de leurs impacts hygrothermiques sur les bâtiments et sur les microclimats urbains. Un modèle physique a été développé pour décrire les mécanismes de transferts couplés de chaleur et de masse au sein de la paroi végétale. L’implémentation de ce modèle dans un code de simulation thermique dynamique permet de prédire l’impact de la végétalisation sur la performance énergétique des bâtiments. L’extension de cette démarche à l’échelle d’une rue-canyon permet d’inclure l’interaction microclimatique dans la simulation thermohydrique des bâtiments. Sur le plan expérimental, une maquette reconstituant une scène urbaine est mise en place pour étudier l’impact de différentes typologies de parois végétales dans plusieurs configurations microclimatiques. La confrontation des résultats expérimentaux et ceux issus de la modélisation numérique a été entreprise à l’échelle du système constitué du bâtiment et du microclimat urbain environnant. Pour cela, l’étude du comportement d’un bâtiment et d’une rue végétalisés par rapport au comportement du même bâtiment et d’une rue témoins a permis d’évaluer l’incidence des transferts thermiques, hygrométriques et radiatifs de la végétalisation. Ceci a permis d’entreprendre la validation des outils de prédiction numérique développés. Les résultats de l’étude montrent que les transferts thermiques et hydriques sont fortement couplés et que le comportement thermique des parois végétales est tributaire de l’état hydrique du substrat de culture. Pour l’été comme pour l’hiver, les simulations numériques et les données expérimentales montrent que la végétalisation permet d’améliorer la performance énergétique des bâtiments et de réduire les îlots de chaleur urbains. / This study was conducted in the framework of the National Program "ANR-VegDUD Project : Role of vegetation in sustainable urban development, an approach related to climatology, hydrology, energy management and environments" (2010 -2013). It deals with the experimental and numerical modeling of green roofs and green facades to evaluate their thermohydric effects on buildings and urban microclimates. A physical model describing the thermal and water transfer mechanisms within the vegetated building envelopes has been developed. The model’s program has been implemented in a building simulation program. Using this tool, we are able to predict the impact of green roofs and green facades on building energy performance. This approach is extended to the street canyon in order to assess the microclimatic interaction in building simulation. An experimental mockup modeling an urban scene at reduced scale is designed to study the impact of different types of green roofs and walls. The comparison of the measurements carried out on vegetated buildings and streets with the reference highlights the hygrothermal and radiative impacts of vegetated buildings envelopes. In addition, these experimental data are used to verify and validate the reliability of developed tools. The results show that thermal and water transfers are strongly coupled. Hence, the thermal behavior of green roofs and green walls depend on the water availability within the growing medium. In summer and winter, measurements and numerical simulations show that green envelopes improve the energy efficiency of buildings and reduce the urban heat island.
160

Contribution à l'étude d'un échangeur de chaleur air-sol (puits canadien) pour le rafraîchissement de l'air sous le climat chaud et semi-aride de Marrakech / Contribution to the study of an earth to air heat exchanger for air cooling in hot and semi-arid climate of Marrakech

Khabbaz, Mohamed 17 December 2016 (has links)
La conception des bâtiments à faible consommation d'énergie est devenue un enjeu très important à travers le monde afin de minimiser la consommation d'énergie et les émissions de gaz à effet de serre associés. Au Maroc, le secteur du bâtiment représente 25% de la consommation énergétique finale du pays avec 18% réservée au résidentiel et 7% pour le tertiaire (ADEREE 2011). L'intégration de systèmes passifs ou semi-passifs de rafraîchissement/chauffage dans le bâtiment est désormais indispensable pour la réduction de la consommation énergétique tout en améliorant le confort thermique. Un de ces systèmes est l’échangeur air-sol (EAHX). Le principe du rafraîchissement à l'aide de l’échangeur air-sol est bien établi, mais le comportement d'un tel système dépend des conditions climatiques et de la nature du sol. L’échangeur air-sol étudié est installé dans une maison type villa située dans la banlieue de Marrakech. Un monitoring de ce système a été réalisé durant l’été 2013 à travers un suivi des températures et de l'humidité durant 39 jours. Les résultats montrent que l’échangeur air-sol est un système adapté pour le rafraîchissement de l’air dans les bâtiments à Marrakech, puisqu’il procure une température de soufflage quasi-constante d’environ 22°C pour le débit 244 m3/h et 25°C pour le débit de 312m3/h, avec une humidité relative autour de 50 % alors que la température extérieure dépasse 40°C. Le modèle mathématique choisi et l’outil de simulation associé, Type 460 opérant sous le logiciel commercial TRNSYS, sont analysés et validés par confrontation avec les résultats expérimentaux. Cette confrontation a montré une excellente concordance, avec un écart absolu moyen entre la mesure et la simulation toujours inférieur à 0,5°C et décroit à 0,2°C à la sortie de tube enterré. La validation de l’outil de simulation avec un échangeur air-sol enterré dans un sol soumis à conditions météorologiques extérieures n’a pas été réalisée auparavant. D'autre part, les simulations dynamiques de l’échangeur air-sol sont réalisées en fonctionnement continu, avec 1 et 3 tubes durant la période chaude de l’année (mai-septembre). Les résultats montrent que le système procure une température à la sortie de tube enterré de 25,1°C (1 tube) et 26 °C (3 tubes). Il en résulte une capacité de refroidissement de 58w/m2 (1 tube) et 55w/m2 (3 tubes) pour une température à l’entrée de 44,6°C. Une étude de sensibilité, utilisant la méthode de Sobol, de la performance thermique de l'échangeur durant la saison chaude (mai-septembre) a permis de dégager les paramètres les plus influents. Par la suite, une étude paramétrique complète sur l’énergie sensible totale perdue par l’air lors dans son passage dans l’échangeur air-sol est réalisée en fonction des paramètres les plus influents déterminés auparavant. / The low energy buildings tendency has become a major worldwide key to minimize energy consumption and greenhouse gas emissions issues. In Morocco, the building sector represents 25% of the total final energy consumption, whereas 18% is dedicated for residential and 7% for the tertiary sector (ADEREE 2011). The integration of passive or semi-passive for cooling/heating purposes into buildings is an essential act for reducing energy consumption while improving thermal comfort. One of these systems is the Earth to Air Heat Exchanger (EAHX). Its principle to use the ground-coupled heat exchanger for cooling is well established, but the behavior of such a system depends on the climate and the soil, which influences the choice of design parameters of this system. We performed a numerical and experimental study on the thermal performance of an Earth to air heat exchanger installed in a villa type house in the suburbs of Marrakech. A monitoring survey was conducted during the summer period of 2013, to acquire temperature and humidity measurements for 39 days. The results show that the earth to air heat exchanger is a system more adapted to refresh the air in buildings in Marrakech, as it provides a quasi constant air temperature of approximately 22°C for flow 244 m3/h and 25°C for flow of 312 m3/h, with relative humidity that is around 50% when the outside temperature exceeds 40°C. The mathematical model chosen and the associated simulation tool used is Type 460 operating under the TRNSYS commercial software, analyzed and validated by comparison with experimental results. This comparison showed excellent agreement, with an average absolute difference between the measurement and simulation that is always lower than 0.5°C and 0.2°C as it decreases at the output of the buried pipe. On the other hand, dynamic simulations of the EAHX using TRNSYS software (TYPE 460) were performed with one pipe or three pipes continuously running. The achieving specific cooling capacity is 58 W/m2 (one pipe) and 55 W/m2 (three pipes) obtained for air temperatures of 25 °C and 26 °C respectively, at the EAHX outlet and 44.6 °C at its inlet. A sensitivity analysis, using the method of Sobol, of the thermal performance of the earth air heat exchanger (EAHX) in the hot season (May-September) has identified the most influential parameters. Thereafter, a complete parametric study on the total sensible energy lost through the air when in passing through the air-ground heat exchanger is made based on the most influential parameters determined previously.

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