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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.
1

Energieffektivisering av ventilationssystem i en skola : Behovsstyrd ventilation i fastigheten Eken i Karlstad kommun / Energy Efficiency of Ventilation System in a School : Demand-Controlled Ventilation for a Building in Karlstad

Johansson, Josefina January 2018 (has links)
I Sverige står bostads-och servicesektorn för nästan 40 % av den totala energianvändningen och därför har många byggnader behov av energieffektivisering. Arbetet utgår från Eken, en del av Karlbergsskolan i centrala Karlstad, som är en kulturmärkt byggnad från 1890-talet. I byggnaden pågår gymnasieutbildning, förskola samt idrottsverksamhet i en gymnastiksal. Byggnaden ventileras i dagsläget med konstant luftflödessystem (CAV). Behovsstyrd ventilation (DCV) innebär att reglera ventilationen efter närvaro och behov, genom att upprätthålla en bra luftkvalité och termisk komfort och samtidigt effektivisera energiförbrukningen. Syftet med detta arbete var att undersöka hur behovsstyrning med IR-sensorer eller CO2-sensorer kan påverka energiförbrukningen och driftkostnader av Ekens ventilationssystem, samt undersöka hur innetemperaturen påverkas vid CO2-reglering jämfört med befintligt driftfall. Målet var att beräkna årliga energibesparingar (MWh/år) och investeringsutrymme (kr) till utgifter som uppkommer vid ombyggnation av dagens CAV-system. Ett ytterligare mål var att beräkna innetemperatur vid olika fall då förutsättningar som rumsplacering, solinstrålning, utetemperatur och intern personbelastning varieras och beroende på CO2-reglerat eller konstant luftflöde. Energibesparingar avseende energi till fläktar och värmebatterier, beräknades i Excel baserat på olika luftflöden beroende på personbelastning. Investeringsutrymmet beräknades utifrån årliga besparingar av driftkostnader. Innetemperaturer beräknades i en dynamisk simuleringsmodell för tre dygn och tre rum med olika förutsättningar. Energibesparingar för IR- och CO2-reglering av ventilationssystemet resulterade i 53 MWh/år (-44 %) respektive 77 MWh/år (-64 %) jämfört med befintligt CAV-system. Efter 15 år bidrog IR- och CO2-reglering till besparingar på ca 520 kkr (IR) respektive 750 kkr (CO2). Skillnaden på innetemperaturen vid behovsstyrt flöde jämfört med konstant luftflöde var lägre än en grad i majoriteten av fallen. Den största skillnaden på 2,7 °C uppstod en solig dag för ett rum med fönster mot sydost. Behovsstyrning är uppenbart fördelaktigt för byggnaden ur energi- och miljöperspektiv. Investeringskostnaden för de två olika metoderna är troligtvis ungefär lika stora och hur ekonomiskt lönsam investeringen är beror på återbetalningstiden. Luftflödesreglering leder inte till några större problem för rumstemperaturen och i annat fall borde temperaturproblem kunna åtgärdas genom solavskärmning eller temporärt ökat ventilationsflöde. / In Sweden, the housing and services sector accounts for close to 40 % of the total energy use, hence why many buildings require energy efficiency. This study is based on the Eken building, which is a historical building from the 1890s, a part of Karlbergsskolan in central Karlstad. The building operates with a secondary education, preschool and a gymnasium. It is currently ventilated by a constant air volume-system (CAV). Demand controlled ventilation (DCV) involves controlling the ventilation according to occupancy and requirement, by maintaining acceptable indoor air quality and thermal comfort, while simultaneously decreasing the energy consumption. The purpose of this study was to investigate how demand-controlled ventilation can improve energy efficiency and operating costs of the ventilation system in Eken, using either IR- or CO2-sensors, as well as investigating how indoor temperature is affected by reduced air flow due to CO2-controlled ventilation. The goal was to calculate the annual energy savings (MWh/year) and anticipate the investment range (SEK) for expenses incurred in rebuilding the current CAV-system. An additional goal was to calculate indoor temperature due to CO2-controlled airflow or constant airflow (CAV) under different circumstances. We did this by varying conditions such as location, solar radiation, outdoor temperature and occupancy. Energy savings for fans and heaters were calculated in Excel, based on different airflows depending on occupancy. The investment range was calculated on the basis of annual savings of operating costs. Indoor temperatures were calculated with a dynamic simulation model for three days, in three rooms, with different conditions. Energy savings for an IR- or CO2-controlled ventilation system resulted in 53 MWh/year (- 44 %) and 77 MWh/year (-64 %) respectively compared to consisting CAV-system. After 15 years, IR- and CO2-regulation contributed to savings of about 520 kkr (IR) and 750 kkr (CO2). The difference of indoor temperature during the demand-controlled flow rate in comparison to constant airflow, was less than one degree in the majority of cases. The biggest difference of 2,7 °C occurred on a sunny day in a room with windows facing southeast. Demand-controlled ventilation is clearly beneficial from an energy- and environmental perspective. The investment cost of the two different methods is probably about the same range and the economic profit depends on the payback period. Airflow regulation does not lead to any major temperature problems, however if there are any problems they may be addressed by solar shielding or temporarily increased air flow rate.
2

Utvärdering av behovsstyrt ventilationssystem i skolbyggnad : Energieffektivisering av ventilation

Kindblom, Johan January 2017 (has links)
New buildings today are built with great care and contain modern technology in order to minimize the energy cost and therefore also their upkeep. This project has tried to evaluate the effect of a smart demand-controlled ventilation system which measures the actual airflow demand and adjusts accordingly. By using exact data from a system inside a school and studying the building itself, an accurate model of the school was created. Using this model the demand-controlled system was compared to a conventional, constant flow, system. The results showed that the demand-controlled system reduced the specific energy consumption of the school by 34 % and that the systems components could be downsized to 70 % of the original size. This means that this kind of integration of control technology is a powerful tool to further increase the energy efficiency in buildings.
3

Behovsstyrdventilation för en befintlig kontorsfastighet : )  En LCC-jämförelse mellan DCV och CAV / Demand controlled ventilation for an existing office building. : - A LCC-comparison between DCV and CAV

Bergsten, Mathias January 2018 (has links)
Demand controlled ventilation has in this study been investigated in a life cycle cost (LCC) - perspective for an existing office property. The goal was to examine whether a complementary of the existing constant air volume (CAV)-system to a demand controlled ventilation (DCV) -system is profitable. This project has been executed on behalf of Fastpartner AB. The studied property is an office building of floor area 6000                          in Stockholm, Sweden. Two different types of DCV systems were analyzed: C controlled ventilation and C with temperature controlled ventilation. The software IDA ICE was used in order to examine the energy consumption for district heating, district cooling and electricity for the air handling unit. The building has been modelled as accuracy as possible in order to represent the real building. In order to see the effect of various loading rate, simulations with three different occupancy levels for CAV and the DCV-systems was made. The occupancy levels represented organizations with high, low and medium occupancy. In the end nine simulations was made. The net present value method was used for each system in the LCC analyses. Costs for installation, purchase and maintenance have been taken into account. The results from the study showed that both of the DCV-systems gives a lower LCC than the existing CAV- system. The most profitable DCV-system is C with temperature- controlled ventilation, that presents a theoretical cost saving up to 250 000 kr. The variation of occupancy levels didn’t affect the outcome of LCC for C and temperature controlled ventilation, however C controlled ventilation showed a significant difference depending on low versus high occupancy level. Low occupancy level results in a higher cost saving. The fans for the air handling unit had the largest energy saving based on energy sector. Where a reduction up to 75 % can be achieved for C controlled ventilation at low occupancy level.
4

Volvo Cars servicestrategi för eftermarknaden

Reimblad, Johan, Kaleby, Erik January 2006 (has links)
Demands on businesses are constantly increasing and the competition in the market-place is becoming ever tougher. To gain the long-term confidence of customers, not only the best businesses, but also the best supply chains are required. Volvo Cars is experiencing a changing competitive situation and their retailers are having trouble stocking the right spare parts. Shorter product life cycles and the growth of Volvo’s product program result in an increase in the number of spare parts to be stocked. In order to adapt to market trends and meet customer demands, Volvo has developed the LDC model, establishing a number of regional warehouses in strategic locations in Sweden, de-signed to supply spare parts to the regions’ retailers through so-called Vendor-Managed In-ventory (VMI). The purpose of the study is to examine Volvo personbilar Sverige’s (VPS) motivation for a modified customer-service strategy through LDC. Furthermore, we aim to survey the LDC model and its function, and to identify the pros and cons of VMI and different inventory strategies. Next we will examine how retailers are affected by a transition to VMI and re-gional distribution centers (the need to adapt the organizations and working methods). Fi-nally we will examine how the alliance with VPS for the retailers choosing to join LDC is transformed, and the potential for improvement for the LDC model in action and in the implementation phase. To attain our purposes, we have chosen conduct interviews with select retailers and key persons at VPS and Volvo Cars. Our conclusions show that VPS has a well-developed strategy behind the LDC model and that VPS’ motive is to enhance customer service and the total performance of the supply chain. The retailers understand the need for change during the introduction of a new logis-tics system. However, our study shows that the biggest problem for the retailers when in-troducing the LDC model is getting employees to change their working methods and rou-tines. An unexpected conclusion of the study was that the alliance and transparence had not changed to the extent we had expected after the introduction of LDC. The most im-portant improvement suggested by the study is that VPS should work to integrate all func-tions and finished products for the after-sales market in the LDC model, allowing them to offer retailers a complete solution.
5

Volvo Cars servicestrategi för eftermarknaden

Reimblad, Johan, Kaleby, Erik January 2006 (has links)
<p>Demands on businesses are constantly increasing and the competition in the market-place is becoming ever tougher. To gain the long-term confidence of customers, not only the best businesses, but also the best supply chains are required.</p><p>Volvo Cars is experiencing a changing competitive situation and their retailers are having trouble stocking the right spare parts. Shorter product life cycles and the growth of Volvo’s product program result in an increase in the number of spare parts to be stocked. In order to adapt to market trends and meet customer demands, Volvo has developed the LDC model, establishing a number of regional warehouses in strategic locations in Sweden, de-signed to supply spare parts to the regions’ retailers through so-called Vendor-Managed In-ventory (VMI).</p><p>The purpose of the study is to examine Volvo personbilar Sverige’s (VPS) motivation for a modified customer-service strategy through LDC. Furthermore, we aim to survey the LDC model and its function, and to identify the pros and cons of VMI and different inventory strategies. Next we will examine how retailers are affected by a transition to VMI and re-gional distribution centers (the need to adapt the organizations and working methods). Fi-nally we will examine how the alliance with VPS for the retailers choosing to join LDC is transformed, and the potential for improvement for the LDC model in action and in the implementation phase.</p><p>To attain our purposes, we have chosen conduct interviews with select retailers and key persons at VPS and Volvo Cars.</p><p>Our conclusions show that VPS has a well-developed strategy behind the LDC model and that VPS’ motive is to enhance customer service and the total performance of the supply chain. The retailers understand the need for change during the introduction of a new logis-tics system. However, our study shows that the biggest problem for the retailers when in-troducing the LDC model is getting employees to change their working methods and rou-tines. An unexpected conclusion of the study was that the alliance and transparence had not changed to the extent we had expected after the introduction of LDC. The most im-portant improvement suggested by the study is that VPS should work to integrate all func-tions and finished products for the after-sales market in the LDC model, allowing them to offer retailers a complete solution.</p>
6

Moderniseringar av tekniska installationer i kulturhistoriskt värdefulla byggnader

Argérus, Simon, Dimitrakis, Sebastian January 2018 (has links)
Studien undersöker om behovsstyrning av inomhusbelysning, ventilationssystem och värmesy- stem är ett effektivt sätt att modernisera kulturhistoriskt värdefulla byggnader. Moderniseringen ska vidare kunna ske utan att förändringen inskränker på byggnadernas individuella bevaran- dekrav. Undersökningen har genomförts på tre byggnader i Lunds kommuns fastighetsbestånd. Byggnaderna som ingår i studien är Ekska huset som uppfördes år 1823, Lunds konsthall som uppfördes år 1956 och Vårfruskolan som byggdes år 1868. Samtliga byggnader innehar ett kul- turhistoriskt värde.Intervjuer med specialister inom byggnadsbevarande, el, ventilation och värme har genomförts för att skapa en förståelse för respektive ämne. Insamlat teoretiskt material har legat till grund för de frågeställningar vi tagit med till intervjuerna. Specialisternas djupgående kunskap och mångåriga erfarenheter har varit nyckeln i analysen av det teoretiska materialet. De förslag på moderniseringar som är framtagna genom studien grundas sammantaget såväl i tidigare forsk- ning som verkliga erfarenheter.Den teknik som används för att behovsstyra olika installationer är fysiskt liten och kan ofta installeras på befintliga installationer. Detta innebär att energieffektiviseringar kan uppnås utan större synliga ingrepp på byggnaderna. Behovsstyrning av installationerna kan därför imple- menteras utan att inskränka på kulturhistoriskt värdefulla byggnaders bevarandekrav.En större mängd styrteknik kan medföra stora energibesparingar. Samtidigt kan modernisering- arna resultera i ökade investerings-, drift- och underhållskostnader. Individuella bedömningar avgör därför hur mycket teknik som är ekonomiskt lönsamt att installera för varje specifik byggnad. / This thesis explores whether, demand-controlled lighting, ventilation and heating is an effective way of modernizing buildings with cultural heritage values. Furthermore, the possibility of modernizing the buildings should not interfere with the individual conservation requirements.A survey has been carried out on three buildings of cultural importance in Lund. The buildings included in the study are Ekska huset built in 1823, Lunds konsthall built in 1956 and Vårfrus- kolan built in 1868.Specialists within the building conservation, electricity, ventilation and heating sectors have been interviewed for the purpose of creating an understanding of the respective subjects. Gath- ered theoretical material has provided the basis for the questions during the interviews. The in- depth knowledge and multiple years of professional experience of the interviewees has been the key in analyzing the theoretical material. The proposals for modernization that have been brought forward through the study is founded in prior research as well as real experiences.The technology used to control the different installations on demand, are physically small and can often be implemented on existing systems. This means that energy efficiency can be achieved without greater visible intervention to the buildings. Demand controlled installations can therefore be implemented without interfering with the conservation requirements of build- ings with a cultural heritage value.A greater amount of control technology can contribute to greater energy savings. However, modernizations can result in increased investment, operating and maintenance costs. Individual assessments therefore determine how much technology is financially beneficial to install for each specific building.
7

Energieffektivisering och dess påverkan på inomhusmiljön - En fallstudie av en kontorsbyggnad

Sandgren, Stefan January 2008 (has links)
Titel: Energieffektivisering och dess påverkan på inomhusmiljön – en fallstudie av en kontorsbyggnad. Syfte: Syftet är att undersöka och utreda resultatet av en energieffektivisering i en befintlig kontorsbyggnad samt att ta reda på hur brukarna upplever inomhusmiljön. Bakgrund: En byggnad, benämnd LU1, på Umeå universitet har i samband med en renovering genomgått en rad energieffektiviserande åtgärder. Ett nytt närvaro- och tryckstyrt luftbehandlingssystem som regleras ända ned på rumsnivå har installerats, en rad styr- och reglertekniska funktioner har implementerats men även en rad andra övriga åtgärder har vidtagits. Metod: Diverse mätningar har utförts i byggnaden tillsammans med en enkätundersökning med brukarna. Slutsats: Den specifika energianvändningen för uppvärmning, kyla och fastighetsel är efter energieffektiviseringen cirka 52 kWh/m2/år vilket går att jämföra med 126 kWh/m2/år som var genomsnittet för 123 kontorsbyggnader i en studie utförd av energimyndigheten. Resultat från både mätningar och enkätundersökning visar på att inomhusmiljön är mycket bra efter de åtgärder som utförts. Samtliga bestämmelser och krav har uppfyllts för inomhusmiljön i LU1 och enkätresultaten visar på mycket nöjda brukare. Den enda punkt där ett missnöje visas gäller sammanträdesrummen. / Title: Energy efficiency improvement and its impact on the indoor climate – A case study of an office building Purpose: The purpose is to examine and investigate the results of energy efficiency improvement in an existing office building and to find out how the working staff experience the indoor climate Background: A building, named LU1, at the University of Umeå has been through a series of energy efficiency measures as the building was renovated. A new presence- and pressure controlled air treatment system that adjusts all the way down to a room level has been installed as well as a series of automatic control functions. A series of other measures have also been taken. Method: Measurements have been made as well as a poll amongst the working staff. Conclusion: The specific energy use for heating, cooling and electricity used for building purposes is about 52 kWh/m2/year after the energy efficient measures were carried out, which compares to 126 kWh/m2/year which was the average for 123 office buildings in a study carried out by Energimyndigheten. The results from both the measurements and the poll however indicates that the indoors climate is very satisfactory after the measures carried out. All rules and regulations have been met for the indoors climate in LU1 and the results from the poll demonstrate that the working staff is very satisfied. The only aspect that indicates any dissatisfaction regards the conference rooms.
8

Energikartläggning och driftoptimering genom behovsstyrning i befintlig fastighet / Energy audit and operational optimization through demand control in existing building

Karlsson, Joakim January 2014 (has links)
Energy supply in Sweden year 2011 amounted to 577 TWh. The final energy consumption for industrial, residential and service was 379 TWh. Sweden has energy policy goals to reduce energy use in buildings. One of these goals is to reduce the energy use by 20 % in 2020 compared to the year 1995. An important step to achieve this goal is to target energy efficiency measures in existing buildings. There are also financial incentives to implement energy efficiency measures due to the fact that the cost of energy represents 30-40% of a buildings maintenance costs. In general, up to 20 % of the energy consumption can be reduced without major reconstruction. In this master thesis project presented here, an energy audit was performed and energy efficiency measures was proposed for an existing building located at Järfälla, Stockholm. The property belongs to SAAB - Defence and Security. They have an internal target to reduce energy use in their buildings with 50 % by 2015 compared to 2009. The work of this master thesis project was limited to a building locally termed hus A. This part of the property is the oldest and was built in 1968, but has expanded gradually to the year 1977. Hus A contains of offices, a production hall, laboratories and storage areas. The energy audit showed that the electricity use is far greater in hus A, compared to the an average office and administration building. This is mainly due to production processes. A breakdown of the highest electricity consumers are: Industrial processes – 61.9 kWh/m2/year Lighting – 35.7 kWh/m2/year Fans – 33.2 kWh/m2/year Refrigeration – 21.8 kWh/m2/year Compressed air – 18.9 kWh/m2/year Computer units – 7.8 kWh/m2/year Frequency converters – 4.4 kWh/m2/year Waste heat from industrial processes, primarily from the production hall leads to high cooling demand to maintain good thermal comfort. Limitations in operation control of the buildings HVAC (Heating, Cooling and Air-conditioning) systems causes high heating and cooling demand and hence the buildings thermal mass is not properly utilized. Energy saving measures was mainly focused on increasing the controlling capability of HVAC systems. By implementing the energy efficiency measures presented in this master thesis report, building thermal mass will be more efficiently utilized. In addition, end use of electricity, heat and cooling will be reduced. In total, seven energy-saving measures proposed.  One measure is implemented to prevent heating and cooling at the same time. A brief description of the energy efficiency measures and the expected result is found below. Adjust set point for TAFA301 Energy saving: 94.0 MWh/yearPayback time: 0 year Establish time schedule for compressed air systemEnergy saving: 110.8 MWh/yearPayback time: 2.5 months Demand controlled temperature set point to heating systemEnergy saving: 167.0 MWh/yearPayback time: 3.5 months Demand control of airflow in the production hallEnergy saving: 155,5 MWh/yearPayback time: 2 years and 10 months Establish time schedule for frequency invertersEnergy saving: 104.0 MWh/yearPayback time: 3 years and 2 months Radiator thermostats to the first part of the production hall Energy saving: 6.5 MWh/yearPayback time: 5 years and 2 months Demand control of airflow in conference roomsEnergy saving: 11.0 MWh/yearPayback time: 12 years and 2 months

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