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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.
51

Implementierung und Validierung eines Algorithmus zur thermischen Simulation von transparenten Bauteilen für die energetische Ertüchtigung von Fenstern im Bestand

Conrad, Christian 21 July 2021 (has links)
Der Klimaschutz ist eine Herausforderung und eine Verantwortung insbesondere gegenüber den nachfolgenden Generationen. Ein Baustein zum Klimaschutz ist die erhebliche Senkung des Energieverbrauches der bestehenden Gebäude. Bei der Sanierung von älteren oder gar zu Denkmalen erklärten Gebäuden stellt die Erhaltung der Originalsubstanz und des Erscheinungsbildes erhöhte Anforderungen an alle am Bau Beteiligten. Für eine energetische Ertüchtigung von historischen Fenstern, welche auch zukünftigen Anforderungen an den Klimaschutz genügen, zeigt diese Arbeit, dass eine detaillierte Planung und eine bauphysikalische Betrachtung notwendig sind. Diese Arbeit leistet einen Beitrag, damit zukünftig das thermische Verhalten der einzelnen Bestandteile (Verglasung, Randverbund, Rahmen) des energetisch ertüchtigten Fensters realitätsnah simuliert und bewertet werden kann. Ausgehend von einer vorbildhaften energetischen Sanierung eines Baudenkmals, welche auch zukünftige Anforderungen an den Klimaschutz genügt, wurden die Erfahrungen der Herstellung der Hochleistungsfenster des Modellgebäudes über die Beobachtungen in einem Zeitraum von über 15 Jahren dargelegt. Bei der Literaturrecherche zum Stand der Wissenschaft und Technik zum Thema Berechnung und Simulation von transparenten Bauteilen wurde besonders auf die freie Konvektion im geschlossenen Scheibenzwischenraum eingegangen. Darauf beruhend wurden eine Parameterstudie und eine Bewertung der Konvektionsmodelle vorgenommen. Das am Institut für Bauklimatik entwickelte numerische Simulationsprogramm [DELPHIN] beruht auf der Finite-Volumen-Methode für opake Bauteile und berücksichtigt den gekoppelten Wärme-, Feuchte-, Luft- und Salztransport für 1D-, 2D- und 3D- Probleme. Dieses Programm wurde parallel zu dieser Arbeit durch das DELPHIN-Entwicklerteam auf der Grundlage der Validierungen mittels Messungen an den Fenstern des Modellgebäudes um die freie Konvektion im geschlossenen Hohlraum zu einem Programm zur Berechnung von transparenten Bauteilen weiterentwickelt. Zusätzlich können damit unter Berücksichtigung der Feuchtespeicherung hygrothermische Schadensprognosen in der Ingenieurpraxis vorgenommen werden. Im Vergleich zur CFD-Simulation wird nur ein Bruchteil der Rechenleistung und Rechenzeit benötigt. Der Ansatz, mit den Messungen der Oberflächentemperatur und der Globalstrahlung senkrecht zur Fassadenebene alle wesentlichen Parameter zu erfassen und durch Nachsimulation von Scheibenoberflächentemperaturen im Kastenzwischenraum das Simulationsmodell und das Programm zu validieren, hat sich bewährt. Durch die Validierung unter Realbedingungen steigt die Akzeptanz dieser Simulation vor allem in der Praxis. Das entwickelte Simulationsmodell stellt ein Werkzeug für die wissenschaftlich gestützte Weiterentwicklung moderner Fenster für die Industrie dar. Zukünftig soll es zur Optimierung von anderen transparenten Bauteilen wie z. B. der thermischen Solarkollektoren sowie der Kombination aus thermischen Solarkollektoren und PV-Kollektoren beitragen. Eine weitere Zielgruppe dieser Arbeit sind Fachplaner und Fachbetriebe, welche sich auf die energetische Sanierung von Bestandsfenstern spezialisiert haben. Die Simulationen der Kastenfenster haben gezeigt, dass bei der Bauteil- und Gebäudesimulation die Berücksichtigung der Absorption der kurzwelligen Strahlung und die daraufhin veränderten freien Konvektionen und der langwellige Strahlungsaustausch in den geschlossenen Hohlräumen nicht vernachlässigt werden können. Der Fehler bei dem Monatsbilanzverfahren zur Berechnung des Heizenergiebedarfes ist bei 2-Scheibenverglasungen noch vertretbar. Bei hochenergieeffizienten Mehrscheibenverglasungen sollte das normative statische Berechnungsverfahren zur U-Wertermittlung von transparenten Bauteilen Verglasungen vorzugsweise durch eine thermische Simulation ersetzt werden. Hierbei sind der Klimastandort und die Ausrichtung für die Absorption der kurzwelligen Strahlung zu berücksichtigen. Eine Vereinfachung für ein Monatsbilanzverfahren für die jeweiligen Klimastandorte der Testreferenzjahre (TRY) [DWD] ist vorstellbar. Bei der Bauteil- und Gebäudesimulation unter Verwendung von Stundenwerten und noch kleineren Zeitschritten sowie in der Hitzeperiode muss diese Modellerweiterung implementiert werden. Durch die realitätsnahe Simulation der Scheibenoberflächentemperaturen auf der Raumseite kann die Empfindungstemperatur berechnet und nachfolgend eine Behaglichkeitsbewertung durchgeführt werden. Die Untersuchungsergebnisse beim Modellgebäude und der Simulation fließen in Vorschläge zur energetischen Ertüchtigung von Bestandsfenstern mittels schmaler Wärmeschutzverglasung mit reduziertem Emissionsgrad ein. Auf der Grundlage dieses Modells kann das Optimum des Scheibenzwischenraumes der einzelnen Edelgase in Abhängigkeit der Neigung ermittelt werden. Das Modell gibt die Möglichkeit zur Bewertung und nachfolgend zur Minimierung von Schadprozessen, welche die Dauerhaftigkeit von transparenten Bauteilen beeinträchtigen. Für die Gebäudesimulation ist die Simulation der Wärmeströme der Verglasung und eine Betrachtung der Strahlungstransmission zu empfehlen. Die separate Simulation von U-Werten ist nicht zu bevorzugen.:1. Motivation, Ausgangssituation und Ziele 9 1.1. Motivation 9 1.2. Ziele, Thesen, Methodik und Relevanz des Dissertationsthemas 11 1.3. Strukturierung der Arbeit 16 2. Modellgebäude Handwerk 15 in Görlitz 17 2.1. Energetisches Gesamtkonzept 18 2.1.1. Dämmmaßnahmen 19 2.1.2. Erneuerung Anlagentechnik 20 2.2. Geschichte und Beurteilung des Denkmalwertes des Modellobjektes 24 2.3. Besondere Anforderungen an die Fenster am Beispiel des Gebäudes Handwerks 15 32 2.3.1. Brandschutzanforderungen 32 2.3.2. Schallschutzanforderungen 33 2.3.3. Belichtung 33 2.3.4. Architektonische Anforderungen-Beibehaltung des historischen Erscheinungsbildes 34 2.4. Energetische Ertüchtigung der Fenster des Modellgebäudes 37 2.4.1. Ausgangssituation 37 2.4.2. Verwendete Verglasung und Low-e-Beschichtung 39 2.4.3. Holz-Kastenfenster mit 2-Scheiben-Wärmeschutzverglasung aus Solarglas 41 2.4.4. Holz-Einfachfenster mit 3-Scheiben-Wärmeschutzverglasung aus Solarglas 44 2.5. Messungen und Beobachtungen am Modellgebäude 46 2.5.1. Messkonzept und Dokumentation des Monitorings und Messerfassungssystems 47 2.5.2. Messaufbau zur Erfassung des Innen- und Außenklimas 48 2.5.3. Bauteilmessstrecke Kastenfenster, 2. OG Nord 50 2.5.4. Bauteilmessstrecke Kastenfenster, 1. DG Süd 54 2.5.5. Bauteilmessstrecke Dachliegefenster, Nord, 2. DG 57 2.5.6. Beschreibung von bauphysikalischen Vorgängen bei den Verglasungen 63 2.5.7. Beschreibung von physikalischen Schadprozessen bei Fenstern 65 2.5.8. Zusammenfassung und Fazit aus den Messungen und den Beobachtungen 70 3. Stand der Wissenschaft und Technik 71 3.1. Aktuelle europäische Normung 72 3.2. Analytisches Modell für die Konvektion innerhalb des Scheibenzwischenraumes 78 3.3. Modell nach ISO 15 099 88 3.4. Modell nach Hollands, Unny, Raithby und Konicek u. a. 90 3.5. Modellzusammenstellung nach Klan und Thess 93 3.6. CFD-Simulationen von Mehrscheibenverglasungen 96 3.6.1. CFD-Simulationen im Vergleich zur DIN EN 673 96 3.6.2. CFD-Simulationen in Kombination mit Messungen im Versuchsstand 102   3.7. Übersicht über die Umsetzung der Verglasungsmodelle in den Computerprogrammen 104 3.7.1. Programm glaCE 3.03 von Glas-Trösch 105 3.7.2. Programm Calumen II 1.3.3/ CalumenLive von SAINT-GOBAIN GLASS 105 3.7.3. Programmpaket Optics, Windows und Therm mit Übergabe in Energy Plus 105 3.7.4. Einzonensimulationsprogramm Therakles 3.0 vom Institut für Bauklimatik 110 3.7.5. Programme der Energieeinsparverordnung 111 3.7.6. Programmpaket PHPP 8 111 3.7.7. Übersicht über die Software zur Berechnung von Verglasungskennwerten 112 3.8. Übersicht über die thermische Beanspruchung von Verglasungen 113 4. Vergleich und Bewertung der Konvektionsmodelle 117 4.1. Analytische Konvektionsmodelle 117 4.2. CFD–Simulation mit EasyCFD 124 4.3. Zusammenfassung und Bewertung der Konvektionsmodelle 125 5. Herleitung und Anwendung des Simulationsmodells 127 5.1. Benennung und Beschreibung der Wärmetransportmechanismen 127 5.2. Algorithmus zur thermischen Simulation von transparenten Bauteilen 140 5.3. Auswertung der Messung und der Simulation bei Kastenfenstern 148 5.4. Validierte thermische Simulation der Kastenfenster 156 5.5. Auswertung der Messung bei dem Dachliegefenster 160 6. Energetische Ertüchtigung von Bestandsfenstern 163 6.1. Situation bei Bestandsfenstern 164 6.2. Beispiele für die energetische Fenstersanierung 166 6.2.1. Bestandskastenfenster 167 6.2.2. Kastenfenster mit K-Glass™ 171 6.2.3. Kastenfenster mit Wärmeschutzverglasung und K-Glass im Innenflügelpaar 174 6.2.4. Kastenfenster mit Wärmeschutzverglasung und K-Glass im Außenflügelpaar 178 6.2.5. Energetische Ertüchtigung durch zusätzliche Fensterebene 182 6.3. Ergebnisse der umgesetzten energetischen Ertüchtigung von Bestandsfenstern 186 7. Zusammenfassung und Ausblick 187 Literaturverzeichnis 189 Anhang 197 Anhang I. Begriffe und Kennzahlen der Strömungsmechanik 197 Anhang II. Eigenschaften von Gasen nach DIN EN 673 199 Anhang III. Berechnung des optimalen Scheibenabstandes 202 Anhang IV. Simulation des optimalen Scheibenabstandes 205 Anhang V. Hinweise zur statistischen Auswertung 208 / Climate protection is a challenge and a responsibility, especially towards future generations. One component of climate protection is the considerable reduction of the energy consumption of existing buildings. When renovating older buildings or even buildings that have been declared monuments, the preservation of the original substance and appearance places increased demands on all those involved in the construction. For an energetic retrofitting of historic windows, which also meet future requirements for climate protection, this work shows that a detailed planning and a structural-physical consideration are necessary. This work makes a contribution so that in the future the thermal behavior of the individual components (glazing, edge seal, frame) of the energetically upgraded window can be realistically simulated and evaluated. Based on an exemplary energetic refurbishment of an architectural monument, which also meets future climate protection requirements, the experiences of the production of the high-performance windows of the model building were presented via the observations over a period of more than 15 years. During the literature research on the state of the art in science and technology on the subject of calculation and simulation of transparent building components, special attention was paid to free convection in the closed space between the panes. Based on this, a parameter study and an evaluation of convection models were carried out. The numerical simulation program [DELPHIN] developed at the Institute of Building Climatology is based on the finite volume method for opaque building components and considers the coupled heat, moisture, air and salt transport for 1D, 2D and 3D problems. This program was further developed in parallel to this work by the DELPHIN development team on the basis of validations by means of measurements at the windows of the model building around the free convection in the closed cavity to a program for the calculation of transparent building components. In addition, hygrothermal damage predictions can be made in engineering practice with this program, taking moisture storage into account. Compared to CFD simulation, only a fraction of the computing power and computing time is required. The approach to capture all essential parameters with measurements of surface temperature and global radiation perpendicular to the facade plane and to validate the simulation model and the program by post-simulation of pane surface temperatures in the inter-box space has proven to be successful. The validation under real conditions increases the acceptance of this simulation, especially in practice. The developed simulation model represents a tool for the scientifically supported further development of modern windows for the industry. In the future, it should contribute to the optimization of other transparent components such as thermal solar collectors as well as the combination of thermal solar collectors and PV collectors. Another target group of this work are professional planners and specialized companies, which have specialized in the energetic renovation of existing windows. The simulations of the box-type windows have shown that in the component and building simulation, the consideration of the absorption of short-wave radiation and the resulting changes in free convection and long-wave radiation exchange in the closed cavities cannot be neglected. The error in the monthly balance method for the calculation of the heating energy demand is with 2-pane glazing is still acceptable. In the case of highly energy-efficient multi-pane glazing, the normative static calculation procedure should be used for the U-value calculation of transparent glazing components should preferably be replaced by a thermal simulation. Here, the climatic location and orientation should be taken into account for the absorption of short-wave radiation. A simplification for a monthly balance procedure for the respective climate locations of the test reference years (TRY) [DWD] is conceivable. For the component and building simulation using hourly values and even smaller time steps as well as in the heat period, this model extension has to be implemented. By the realistic simulation of the pane surface temperatures on the room side, the sensation temperature can be calculated and subsequently a comfort evaluation can be carried out. The results of the investigations in the model building and the simulation are incorporated into proposals for the energy upgrading of existing windows by means of narrow thermal insulation glazing with reduced emissivity. On the basis of this model, the optimum of the space between the panes of the individual noble gases can be determined as a function of the inclination. The model gives the opportunity to evaluate and subsequently minimize damage processes that affect the durability of transparent building components. For the building simulation, the simulation of the heat fluxes of the glazing and a consideration of the radiation transmission is recommended. The separate simulation of U-values is not to be preferred. The advice on the design or evaluation of the impairment due to condensation and frost formation on the outside of the glazing of transparent constructions should be continued by implementing the slope dependence of convection in the software and a validation by comparing measurement and simulation.:1. Motivation, Ausgangssituation und Ziele 9 1.1. Motivation 9 1.2. Ziele, Thesen, Methodik und Relevanz des Dissertationsthemas 11 1.3. Strukturierung der Arbeit 16 2. Modellgebäude Handwerk 15 in Görlitz 17 2.1. Energetisches Gesamtkonzept 18 2.1.1. Dämmmaßnahmen 19 2.1.2. Erneuerung Anlagentechnik 20 2.2. Geschichte und Beurteilung des Denkmalwertes des Modellobjektes 24 2.3. Besondere Anforderungen an die Fenster am Beispiel des Gebäudes Handwerks 15 32 2.3.1. Brandschutzanforderungen 32 2.3.2. Schallschutzanforderungen 33 2.3.3. Belichtung 33 2.3.4. Architektonische Anforderungen-Beibehaltung des historischen Erscheinungsbildes 34 2.4. Energetische Ertüchtigung der Fenster des Modellgebäudes 37 2.4.1. Ausgangssituation 37 2.4.2. Verwendete Verglasung und Low-e-Beschichtung 39 2.4.3. Holz-Kastenfenster mit 2-Scheiben-Wärmeschutzverglasung aus Solarglas 41 2.4.4. Holz-Einfachfenster mit 3-Scheiben-Wärmeschutzverglasung aus Solarglas 44 2.5. Messungen und Beobachtungen am Modellgebäude 46 2.5.1. Messkonzept und Dokumentation des Monitorings und Messerfassungssystems 47 2.5.2. Messaufbau zur Erfassung des Innen- und Außenklimas 48 2.5.3. Bauteilmessstrecke Kastenfenster, 2. OG Nord 50 2.5.4. Bauteilmessstrecke Kastenfenster, 1. DG Süd 54 2.5.5. Bauteilmessstrecke Dachliegefenster, Nord, 2. DG 57 2.5.6. Beschreibung von bauphysikalischen Vorgängen bei den Verglasungen 63 2.5.7. Beschreibung von physikalischen Schadprozessen bei Fenstern 65 2.5.8. Zusammenfassung und Fazit aus den Messungen und den Beobachtungen 70 3. Stand der Wissenschaft und Technik 71 3.1. Aktuelle europäische Normung 72 3.2. Analytisches Modell für die Konvektion innerhalb des Scheibenzwischenraumes 78 3.3. Modell nach ISO 15 099 88 3.4. Modell nach Hollands, Unny, Raithby und Konicek u. a. 90 3.5. Modellzusammenstellung nach Klan und Thess 93 3.6. CFD-Simulationen von Mehrscheibenverglasungen 96 3.6.1. CFD-Simulationen im Vergleich zur DIN EN 673 96 3.6.2. CFD-Simulationen in Kombination mit Messungen im Versuchsstand 102   3.7. Übersicht über die Umsetzung der Verglasungsmodelle in den Computerprogrammen 104 3.7.1. Programm glaCE 3.03 von Glas-Trösch 105 3.7.2. Programm Calumen II 1.3.3/ CalumenLive von SAINT-GOBAIN GLASS 105 3.7.3. Programmpaket Optics, Windows und Therm mit Übergabe in Energy Plus 105 3.7.4. Einzonensimulationsprogramm Therakles 3.0 vom Institut für Bauklimatik 110 3.7.5. Programme der Energieeinsparverordnung 111 3.7.6. Programmpaket PHPP 8 111 3.7.7. Übersicht über die Software zur Berechnung von Verglasungskennwerten 112 3.8. Übersicht über die thermische Beanspruchung von Verglasungen 113 4. Vergleich und Bewertung der Konvektionsmodelle 117 4.1. Analytische Konvektionsmodelle 117 4.2. CFD–Simulation mit EasyCFD 124 4.3. Zusammenfassung und Bewertung der Konvektionsmodelle 125 5. Herleitung und Anwendung des Simulationsmodells 127 5.1. Benennung und Beschreibung der Wärmetransportmechanismen 127 5.2. Algorithmus zur thermischen Simulation von transparenten Bauteilen 140 5.3. Auswertung der Messung und der Simulation bei Kastenfenstern 148 5.4. Validierte thermische Simulation der Kastenfenster 156 5.5. Auswertung der Messung bei dem Dachliegefenster 160 6. Energetische Ertüchtigung von Bestandsfenstern 163 6.1. Situation bei Bestandsfenstern 164 6.2. Beispiele für die energetische Fenstersanierung 166 6.2.1. Bestandskastenfenster 167 6.2.2. Kastenfenster mit K-Glass™ 171 6.2.3. Kastenfenster mit Wärmeschutzverglasung und K-Glass im Innenflügelpaar 174 6.2.4. Kastenfenster mit Wärmeschutzverglasung und K-Glass im Außenflügelpaar 178 6.2.5. Energetische Ertüchtigung durch zusätzliche Fensterebene 182 6.3. Ergebnisse der umgesetzten energetischen Ertüchtigung von Bestandsfenstern 186 7. Zusammenfassung und Ausblick 187 Literaturverzeichnis 189 Anhang 197 Anhang I. Begriffe und Kennzahlen der Strömungsmechanik 197 Anhang II. Eigenschaften von Gasen nach DIN EN 673 199 Anhang III. Berechnung des optimalen Scheibenabstandes 202 Anhang IV. Simulation des optimalen Scheibenabstandes 205 Anhang V. Hinweise zur statistischen Auswertung 208
52

Centrum léčby roztroušené sklerozy / Centre for treatment of sclerosis' multiplex

Beláčková, Katarína January 2015 (has links)
The building of the monastery is located on the edge of the historic town of Prostejov. Currently unused and falling into disrepair. Work creates a new concept for functional use of the monastery and garden. The building opens up new entry from Vojáčkova Square. On the ground floor there is a function for the city's residents as a community center or gallery, pharmacy and smaller commercial areas. The rest of the object is dedicated to the center of multiple sclerosis. The facility is 27 beds, rooms for occupational therapy, physiotherapy. There's designed object of swimming pool and other facility needed for centre work . The area is a large garden for daily use patients and citizens.
53

Cirkulära affärsmodeller som ettverktyg för fördröjdmaterialanvändning : En kvalitativ studie av cirkulära möbelflöden på KTH / Circular business models as a tool for slowing resource usage : A qualitative study of circular furniture flows at KTH

Zetterberg, Edwina, Gerdbo, Sara January 2022 (has links)
Denna rapport är en kvalitativ undersökning av cirkulära möbelflöden som verktyg för fördröjd materialanvändning. Dagens konsumtions- och produktionsmönster är inte förenliga med målen hållbar utveckling. Genom att ersätta linjära affärsmodellerna med cirkulära affärsmodeller kan resurseffektivisering och materialbesparing åstadkommas. De har som mål att fördröja eller sluta materialcykeln vilket kräver olika insatser i designfasen som gör produkter lämpliga för återanvändning, materialåtervinning eller förlängd livscykel.  För närvarande pågår ett renoveringsprojekt av en K-märkt byggnad som tillhör CBH-skolan på KTH där även inventarierna kommer rustas upp. Möblerna kommer i första hand renoveras och återbrukas för att bli en del av ett cirkulärt möbelflöde vilket kräver implementering av cirkulära affärsmodeller. I denna studie undersöks hur återbruket av möblerna, specifikt mötesstolar, hanteras på KTH samt vilka hinder som finns i praktiken vid implementering av cirkulära affärsmodeller och återbruk. Studiens övergripande metoder för att besvara frågeställningarna består av litteraturstudier, intervjuer och inventering. Resultaten från dessa har analyserats och utvärderas i förhållande till befintliga cirkulära affärsmodeller.  Utifrån studien har det identifierats att det på KTH främst finns organisatoriska hinder på grund av avsaknaden av centraliserade beslut som främjar cirkulära möbelflöden. Det saknas ett helhetsgrepp som minskar incitamenten att styra mot ett cirkulärt flöde och det blir då enklare att agera efter linjära affärsmodeller. Dagens marknad är i mångt och mycket anpassad efter linjära affärsmodeller och det leder till att verksamheter riskerar att konkurrera ut sig själva i den cirkulära omställningen. Därför krävs en större acceptans för mer cirkulära användningsmönster och starkare incitament att få marknaden att ställa om. / This is a qualitative study about how circular furniture flow works as a tool to slow the use of material resources. Our modern ways of consumption are not aligned with sustainable development. The substitution of linear business models with circular business models can contribute to resource efficiency and material savings. The main goal of circular business models is to either slow or close the material cycle, and products need to be designed for reuse, recycling, or a prolonged life cycle.  There is an ongoing renovation of the listed building used by the school of CBH at KTH. Along with the renovation, the furniture is also being refurbished. The current furniture will primarily be renovated and reused with the goal of creating a circular furniture flow by implementing circular business models. This study examines how the refurbishment of chairs is handled at KTH by observing the main challenges for implementing circular business models. This has been done with the help of literature studies, qualitative interviews, and an inventory of chairs. The results have been analyzed and compared to existing circular business models.  Based on this study, the main challenges are identified as organizational due to the lack of centralized decisions in favor of circular furniture flows. There is a lack of a holistic approach that creates incentives to move the organization in a more circular direction and to obstruct the use of linear business models. The market is mostly adapted for linear business models, and businesses are at the risk of outcompeting themselves by adopting more circular approaches. Circular usage needs to be widely accepted with the help of stronger incentives to move in a more circular direction.
54

Förutsättningar för en cirkulär möbelindustri : en fallstudie på ett nordiskt möbelföretag / Prerequisites for a circular furniture industry : a case study of a Nordic furniture company

Axelsson, Fritjof, Ericson, Tim January 2023 (has links)
The furniture industry is an integral part of the European economy and is now facing economic, environmental, and regulatory challenges. Within the European Union (EU), a large amount of furniture every year goes to incineration or landfill, with only 10% being recycled. One of the causes is the increased supply of low-quality furniture that is put on the market, causing increased consumption levels, resulting in an increasing amount of waste. Additionally, most of the climate impact occurs within the extraction of raw materials. From an environmental perspective, vast opportunities present themselves. Simultaneously, new stricter legislation demands decreased use of resources and climate impact, and the introduction of new circular economy guidelines forces companies to act. By adopting a circular approach in the organisation, companies can improve their resource usage and climate impact. However, the adoption itself demands new types of business models, which is a challenge for the corporates in the furniture industry to realize.  The furniture industry can be split into two sections, business to business (B2B) and business to consumer (B2C), where the first one has reached a bit further than the latter, regarding circularity. This can be explained, among other things, by knowledge gaps between the two sections and that Product-Service System (PSS) is more established for B2B. PSS integrates products and services to fulfil the customer’s needs, which is seen as an enabler for circular economy. The aim of this thesis is to explore the furniture industry within B2C in Sweden by identifying which circular business practices are offered today, as well as exploring the challenges and opportunities for furniture companies to implement more circular business practices. In addition, it examines which prerequisites are central to a more circular furniture industry. To achieve the purpose of this thesis, a qualitative approach has been used through a case study at a large Swedish B2C furniture company. Data has been collected through a literature study and an interview study where a total of 14 respondents have been interviewed. The interviewees consisted of both internal respondents at the case company as well as external parties consisting of experts and suppliers. In addition, a mapping consisting of a website study has been conducted to identify the current circular business practices that B2C furniture companies offer in Sweden today. The result indicates that linear business models are currently dominating in the furniture industry and that there is an extensive demand for low-priced furniture, which often lacks quality. Regarding circular business practices, there is a limited amount that is being offered on the market. Out of 40 companies considered, four offered two circular business practices, 18 companies offered one circular business practice and 18 companies offered none. The offers included furniture care guides, reconditioning services, furniture leasing, recycling guides and second-hand sales. The most central obstacles a circular furniture industry faces are the price aspect and the consumer attitude, where circular initiatives in many cases can be more expensive compared to buying new products. Cheap furniture has worse prerequisites for circularity due to the inadequate design and lack of spare parts. In addition, the hygiene aspect and logistical issues were found to be central barriers as well. On the other hand, one major opportunity for circular business practices is changes in consumer attitudes, which is changing with the coming generation due to an increasing interest in sustainability. Furthermore, there are upcoming directives and legal requirements as well as benefits consisting of increased profitability for companies in an early transition to a more circular business. The most essential prerequisites to enable a more circular furniture industry is enabling cooperation between actors and joint efforts to change current trends. It is thus clear that a change in the furniture industry is required, which requires actors to dare to change towards a more circular business.
55

Energy savings potential of building envelope refurbishment in Swedish single-family houses

Kousah, Rami January 2023 (has links)
Sweden has ca. 2 million single family houses (SFH) housing 52% of the population and representing 44.6% of the overall heated floor area. SFHs account for 39.5% of the total heating demand in Sweden. Energy consumption in older SFHs is much higher than in new ones. SFHs built in the 1960s consume ca. 170% of the annual heating energy demand of SFH built in the 2010s. This study aims to explore the energy savings potential in existing SFHs built between 1960 and 1975 in Sweden through refurbishment of elements of the building envelope and analyze their energy and costefficiency of these measures. Furthermore, it aims to study the effects of variations in climate in Sweden on the energy and cost efficiency of these measures. A hypothetical un-refurbished SFH was modeled and defined using energy simulation tool IDA-ICE based on statistical data and relevant literature reviews. Variations in climate between regions of Sweden were analyzed and 4 suitable locations were suggested to place the hypothetical model in. Suitable building envelope refurbishmentmeasures were selected for the elements of the building envelope. These measures were (a) adding extra insulation to the outer side of external wall (b) replacing and insulating the slab on ground (c) insulating the cold attic on top the existing horizontal slab, and (d) replacing the exiting external doors and windows. Suggested U-values for renovated SFHs from Boverket were used as a goal for the suggested refurbishment measures to reach. Energy performance simulations were performed to estimate savings potential in energy used for heating purposes for the un-refurbished building and each of the suggested measures. Life cycle cost (LCC) study using UPV* method was performed over a lifespan of 30 years. The results of the energy performance simulation showed energy savings potential in all the suggested measures, ranging from ca. 6% to ca. 20% with the measure of replacing the external doors and windows had the most savings potential. The study highlighted rate of improvement in U-values, surface area within which heat losses are occurring, status of thermal bridges, and differences in temperature between air and soil as factors effecting the energy savings potential. The results showed no significant effects of changing locations on the savings potential. LCC analysis showed that the measure of adding extra insulation in the cold attic is the most cost-efficient. It also showed that higher heating demands in colder climate led to more significant role for the energy savings potential in determining the cost efficiency, while the initial costs played a bigger role in warmer climate. The study also showed that choosing materials and products with longer lifespan in addition to having a good energy savings potential may lead to a change in results on the cost-efficiency analysis. The study concludes with highlighting the energy savings potential in building envelope refurbishment and the importance of including both and energy and cost efficiency perspectives when choosing refurbishment measures for existing SFH.
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Embodied carbon and waste generation of building refurbishment : Case studies of office fit out in Sweden / Inbyggd kol och avfallsgenerering vid renovering av byggnader : Fallstudier av hyresgästanpassning i kontorsbyggnader i Sverige

Budiyani, Ansheila Gabriela January 2023 (has links)
Buildings contribute to various environmental impacts. Office fit out, as a type of refurbishment in the building life cycle, tends to recur often and is resource-intensive. Still few studies have researched the topic. Through four fit out case studies in offices in Sweden, this study investigates the impacts of office fit out by calculating the waste generation and embodied carbon of fit out. The results show that the waste generation and embodied carbon for each case study projects was 31-38 kg/m2 refurbished GFA and 93-96 kg CO2e/m2 refurbished GFA. Over time, the accumulated recurring embodied carbon of fit out can surpass the initial embodied carbon of the building when no improvement for embodied carbon reductions is made. Scenarios modelling explores how prolonging fit out recurrency and incorporating circular methods to the practice could reduce the accumulation of embodied carbon of fit out. According to the results, recommendations for the actors involved are proposed and methodological reflections are presented. This study provides an overview and initial understanding of the impacts of fit out from real-life cases to help identify what can be done to reduce environmental impacts. / Byggnader bidrar till olika typer av miljöpåverkan. Hyresgästanpassning i kontorsbyggnader är en typ av renovering under en byggnads livscykel som tenderar att upprepas många gånger och är resurskrävande. Trots det är det få studier som än så länge har undersökt ämnet. Genom fyra fallstudier av hyresgästanpassningsprojekt i kontorsbyggnader i Sverige studeras effekterna av hyresgästanpassning genom att beräkna generering av avfall och inbyggd klimatpåverkan (eng. embodied carbon). Resultaten visar att för de fyra fallstudierna genereras avfall i omfattningen 31-38 kg/m2 renoverad BTA och inbyggd klimatpåverkan i omfattningen 93-96 kg CO2e/m2 renoverad BTA. Över tid kan den ackumulerade inbyggda klimatpåverkan av återkommande hyresgästanpassningsprojekt överskrida byggnadens initiala inbyggda klimatpåverkan när inga strategier för att minska inbyggd klimatpåverkan tillämpas i projekten. Modellering av ett antal scenarier undersökte hur en lägre frekvens av återkommande hyresgästanpassningsprojekt och införlivning av cirkulära strategier kan minska ackumuleringen av inbyggd klimatpåverkan över byggnadens livscykel. Baserat på studiens resultat föreslås rekommendationer till berörda aktörer och reflektioner som rör beräkningsmetoden presenteras. Den här studien ger en översiktlig förståelse av klimatpåverkan av hyresgästanpassning i kontorsbyggnader från verkliga fallstudier, vilket kan bidra med att identifiera vad som kan göras för att minska miljöpåverkan.
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[en] ASSESSMENT OF ENERGY LOSSES AND CHARACTERIZATION OF THE RESALE AND MAINTENANCE MARKET OF REFURBISHED ELECTRIC MOTORS IN BRAZIL / [pt] AVALIAÇÃO DAS PERDAS ENERGÉTICAS E CARACTERIZAÇÃO DO MERCADO DE REVENDA E DE MANUTENÇÃO DE MOTORES ELÉTRICOS RECONDICIONADOS NO BRASIL

RODRIGO SANTOS VIEIRA 20 February 2019 (has links)
[pt] Os motores elétricos no Brasil são responsáveis pelo consumo de cerca de 25 porcento de toda a energia elétrica no país e, em sua grande parte, estão presentes na indústria. Estes equipamentos são fabricados para uso em bombas hidráulicas, compressores de ar, elevadores etc., podendo ser comercializados se atenderem aos índices de eficiência mínimos definidos pela Portaria INMETRO/MDIC N488 de 2010, garantindo o seu perfeito funcionamento e o consumo energético adequado. Contudo, alguns estabelecimentos estão comercializando produtos usados recondicionados, não atendendo à regulamentação desta Portaria, além de reformarem motores sem condições de uso. O objetivo desta dissertação é dimensionar e caracterizar o mercado de revenda e manutenção de motores elétricos de indução recondicionados no Brasil, estimando a perda de energia decorrente do recondicionamento incorreto. A metodologia do trabalho pode ser dividida em cinco etapas: estudo do estado da arte de recondicionamento de motores; quantificação de empresas e funcionários por meio de consultas às bases de dados governamentais; pesquisa de campo em amostras de empresas que fazem recondicionamento; extrapolação do estudo conduzido nas amostras para a população de empresas pesquisadas durante a pesquisa de campo; comparação dos resultados com estudos anteriores e dimensionamento das perdas elétricas do Brasil. Como resultado foi caracterizado e dimensionado o mercado de motores recondicionados, contendo: 6.503 empresas; 24,4 mil funcionários; 45 porcento das empresas realizando revenda de recondicionados; 6,9 milhões de motores recondicionados por ano, totalizando 7,46 porcento de perda, equivalentes a 2,9 Terawatt-hora. Além disso, dos 20 milhões de motores existentes no Brasil em 2016 há uma perda de 8,4 Terawatt-hora por uso de motores recondicionados e um grande aumento da venda de motores importados de baixa qualidade. Foram, assim, atingidos todos os objetivos propostos nesta pesquisa, sendo identificadas as novas tendências do mercado de motores brasileiro e gerando subsídios para o desenvolvimento de novas políticas de eficiência energética no país. / [en] Electric motors in Brazil are responsible for the consumption of about 25 percent of all electricity in the country and, being mostly presented in the industry. These equipments are manufactured for being used in hydraulic pumps, air compressors, elevators, etc., and can be commercialized in compliance with the energy efficiency levels defined by INMETRO/MDIC Ordinance N488 of 2010, ensuring adequate energy consumption. However, some establishments are commercializing refurbished motors, not complying with the regulation considered by the Ordinance, including reforming motors without a minimum condition of use. The aim of this dissertation is to evaluate the Brazilian market of refurbished motors, including resale market and maintenance market, estimating the energy losses due to incorrect reconditioning. The methodology of the work can be divided in five steps: state of the art of refurbished motors; quantifying companies and employees by querying the database come from the government; survey on samples of companies that are doing the refurbishing service; extrapolation of the study conducted in the surveyed samples of companies to the population of companies; comparison of results with previous studies and estimating of energy losses in Brazil. As a result, the market for refurbished motors was characterized and dimensioned, containing: 6 503 companies; 24.400 employees; 45 percent of companies performing resale of refurbished motors; 6.9 million motors being refurbished per year, totaling 7.46 percent of energy losses, equivalent to 2.9 TW h. In addition, of the 20 million motors remaining in Brazil in 2016, there is a loss of 8.4 TW h per use of refurbished motors, and a large increase of the sale of low quality imported motors. Thus, all the proposed objectives in this dissertation were achieved, having been identified the new trends in the Brazilian electric motor market and generating subsidies for energy efficiency policies in the country.
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Energy Renovation: A case study of a multi-family house built during the Million program in Djursholm

Bold, Adiltogtokh January 2022 (has links)
Large share of Swedish building stock were built during 1940-1980 when people were not fully aware of the energy efficiency concept. Majority of the buildings that made energy declaration are in energy class E-G, which are considered as high energy consumption buildings with low energy performance, and only few buildings meet the Swedish requirements for near zero energy buildings which are in energy class A-C. The energy renovation rate of the existing buildings is low and more needs to be done to make the Swedish building stock energy and resource efficient. In this thesis the potential of energy efficiency improvement is investigated for an old multi family house built during the Million program in Sweden. Passive energy renovation measures on the demand-side along with active energy renovation measures on the supply-side were investigated together with their combinations resulting in eight different cases. The investigated demand-side refurbishments are additional attic floor insulation and replacement of windows with insulated glass windows while the supply-side refurbishments are rooftop PV installation and conversion to water-based heating system with GSHP. The results of this study show that combination of all four energy efficiency measures has the highest energy-saving potential and yields the highest NPV compared to the other cases for an assumed real discount rate of 3% and grid purchase price of 1.60 SEK/kWh, while requiringthe highest CAPEX. On the other hand, GSHP with water-based heating system requires two times lower CAPEX, however, has high energy-saving potential and yields high NPV. / En stor del av Sveriges byggnadsbestånd byggdes under 1940-1980, då folk inte var fullt medvetna om energieffektiviseringskonceptet. Större delen av byggnaderna som har upprättat energideklaration är i energiklass E-G vilket anses vara byggnader med hög energibrukning med låg energiprestanda och endast ett fåtal byggnader uppfyller de svenska kraven som ställs för nära noll energi byggnader som är i energiklass A-C. Energirenoveringstakten i de befintliga byggnaderna är låg och mer behöver göras för att göra Sveriges byggnadsbestånd energi- och resurseffektivt. I detta examensarbete undersöks potentialen för energieffektivisering i ett äldre flerfamiljshus som byggdes under Miljonprogrammet i Sverige. Passiva energirenoveringar som avser energiefterfrågesidan såväl som aktiva energirenoveringar som avser energiförsörjningssidan undersöktes tillsammans med deras kombinationer, vilket resulterade i åtta olika fall. De undersökta energirenoveringarna som avser energiefterfrågesidan är tilläggsisolering av vindbjälkslag och byte av fönster till isolerglas medan energirenoveringarna som avser energiförsörjningssidan är installation av solceller på taket och konvertering till vattenburen värme med bergvärmepump. Resultatet av denna studie visar att kombinationer av alla fyra energieffektiviseringsåtgärder har den högsta energibesparingspotentialen och ger den högsta NPV jämfört med de andra fallen för en antagen real kalkylränta på 3% och ett elpris på 1.60 SEK/kWh, samtidigt som det kräver högst CAPEX. Däremot, bergvärmepump med vattenburen värme kräver två gånger lägre CAPEX, samtidigt som det har hög energibesparingspotential och ger hög NPV.
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Indirekt klimatpåverkan vid renovering av lokaler inom fastighetsbranchen : En fallstudie rörande Hufvudstadens scope 3-utsläpp vid ombyggnation / Indirect climate impact during renovation within the real estate market : A case study concerning the scope 3-emissions arising from refubishments of Hufvudstadens´s facilities

Ernström, Simon January 2020 (has links)
Bakgrund: Bygg- och fastighetsbranschens växthusgasutsläpp i Sverige står i paritet med utsläppen från inrikes transporter i Sverige. För att uppnå Sveriges regerings mål om att landets nettoutsläpp av växthusgaser ska vara noll vid 2045 krävs en omställning i branschen. Av de totala växthusgasutsläppen från bygg- och fastighetsbranschen står ombyggnationer och förvaltning för cirka 20 procent. För att kunna minska dessa utsläpp krävs det att fastighetsägare har möjlighet att ta medvetna val vid ombyggnationer för att minska deras klimatpåverkan. Det finns studier som fokuserar på klimatberäkning vid nybyggnationer av byggnader, men en aspekt som oftast utelämnas är klimatberäkningar vid ombyggnationer och renoveringar, trots att dessa bidrar med en betydande del av de totala växthusgasutsläppen från branschen. Syfte: Studiens syfte är att undersöka möjligheten för fastighetsbolag att beräkna deras indirekta klimatutsläpp från ombyggnationer, samt att modellera en typisk ombyggnation för att estimera dess klimatpåverkan i form av koldioxidekvivalenter per kvadratmeter. Metod: Studien utgår från forskning inom området för livscykelanalyser och information från leverantörer inom bygg- och fastighetsbranschen genom årsredovisningar, hållbarhetsrapporter och information från hemsidor. Studien är baserad på en fallstudie bestående av en nulägesanalys av fyra leverantörer anlitade av Hufvudstaden vars hållbarhetsarbete analyserades, samt modellering av en typisk ombyggnation genomförd av Hufvudstaden. Modelleringen genomfördes med hjälp av programmet One Click LCA (2015) där klimatdata om material kunde inhämtas från programmets databas. Slutsats: Studien visar att möjligheterna för att fastighetsbolag ska kunna beräkna deras indirekta klimatutsläpp vid ombyggnationer beror till stor del av kvalitén av informationsutbyte mellan leverantörer och fastighetsbolag, vilket visade sig variera mellan olika företag. Bristen på kunskap om hur man genomför livscykelanalyser är också ett hinder som framkommit av studien. Resultatet av modelleringen visade att en typisk ombyggnation ger upphov till ett klimatutsläpp på 210 𝑘𝑘𝑘𝑘 𝐶𝐶𝐶𝐶2𝑒𝑒/𝑚𝑚2. / Background: Greenhouse gas emissions from the construction and real estate industry in Sweden stands for approximately the same amount as the emissions from Sweden’s domestic transports. To achieve Sweden´s governments goal that Sweden´s net emissions of greenhouse gases should become zero until 2045 a major readjustment in the industry is needed. Greenhouse gas emissions from reconstruction and management stands for approximately 20 percent of the total emissions from the whole construction and real estate industry. To reduce these emissions real estate owners must be able to take suitable options regarding material in the reconstruction process to be able to reduce their emissions. Most studies focus on climate calculation regarding new buildings, but often excludes emissions from reconstruction and refurbishments, although they stand for a significant part of the total emissions from the industry. Purpose: This study aims to investigate the possibility for a real estate owner to calculate their indirect emissions from reconstructions and construct a model for a typical reconstruction and estimate its climate emissions in terms of carbon dioxide equivalents per square meter. Method: The study is based on research in the field of life cycle analysis and information from suppliers within the construction and real estate industry through annual reports, sustainability reports and information from their websites. The study is based on a case study including an analysis of four suppliers and how they work with climate and model of a typical reconstruction of an office owned by Hufvudstaden. The model was based on the program One Click LCA (2015) where climate data could be retrieved from their database. Conclusions: The study show that it is important with information exchange between real estate owners and their suppliers to be able to calculate their indirect climate emissions, which can vary a lot between different companies. The lack of knowledge about life cycle analysis can also cause troubles while trying to get climate data about the material that is used during the reconstruction phase. The result from the modelling showed that a typical reconstruction causes climate emission of 210 𝑘𝑘𝑘𝑘 𝐶𝐶𝐶𝐶2𝑒𝑒/𝑚𝑚2.
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Design d'un territoire avec des bâtiments sans énergie fossile à l'horizon 2050 / Design no fossil fuel consumptions in building sector for 2050

Kotnarovsky, Grégory 27 February 2013 (has links)
Avec 42% de la consommation d'énergie finale et 25% des émissions de CO2, le secteur des bâtiments en France représente un enjeu majeur pour maîtriser la facture énergétique des ménages, des collectivités et de l'État. Cette thèse s'attache ainsi à analyser la façon dont les territoires sont en capacité de s'engager dans des projets destinés à réduire les consommations énergétiques des bâtiments. Elle propose de formaliser une démarche de conception collaborative de programmes d'efficacité énergétique des bâtiments, mobilisable par des acteurs souhaitant s'engager dans de tels projets. L'hypothèse de base de la thèse consiste en effet à affirmer qu'une amélioration significative et durable des bâtiments ne peut s'envisager sans revoir en profondeur le fonctionnement actuel du secteur bâtiment-énergie afin de l'engager vers un modèle basé sur l'économie de fonctionnalité. Trois terrains d'expérimentations ont servi de référence à la construction de l'argumentation et à sa validation : les départements de Meuse et de Haute-Marne, les villages de Dammarie-sur-Saulx et Epizon, et la ville de Commercy.Ce travail conclut sur les facteurs clés de succès d'un programme d'efficacité énergétique et de son évaluation ; la nécessité d'avoir un nouveau modèle économique comme repère pour fonder la pertinence de l'action. Elle souligne enfin son intérêt pour d'autres programmes prenant en charge une évolution de l'organisation de la filière du bâtiment / With 42% of the final energy consumption and 25% of CO2 emissions, the French building sector represents a major challenge to manage the energy bill for households, regional communities and the State. This doctoral thesis analyses how communities are able to be involved in projects aiming at reducing energy consumptions in buildings. It proposes to formalize a collaborative design process of energy efficiency program, usable for local actors. The original thesis hypothesis asserts that a significant improvement of the energy efficiency in buildings depends on a paradigm shift of the economic model and proposes the functional economy as a potential solution. Three experimentations were followed to build the argumentation and its validation: the departments of Meuse and Haute-Marne, the two villages of Dammarie-sur-Saulx (Meuse) and Epizon (Haute-Marne) and the city of Commercy (Meuse). This work defines on key success factors of a energy efficiency program and its assessment; the need to use a new economic model as a landmark to establish the action relevance. This work highlights also other programs taking account an evolution of the building sector organisation

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