Spelling suggestions: "subject:"boperating anda maintenance costs"" "subject:"boperating ando maintenance costs""
1 |
Osäkerhet i investerares avkastningsbedömning av kommersiella fastigheter. - Osäkerheter i bedömningen av drift- och underhållskostnader? / Uncertainty in investors' return assessment of commercial real estate. - Uncertainties in the assessment regarding the operating and maintenance costs?Ekeberg, Sanna, Karlsson, Viktor January 2015 (has links)
No description available.
|
2 |
LCC and LCA for Low Temperature Heating Integrated with Energy Active Envelope SystemsBuitrago Villaplana, Esther January 2020 (has links)
Windows has been always considered as heat sinks and they can account more than 25% of a building envelope. For this reason, its design and performance in dwellings play a major role in regulating the indoor environment. The construction sector has been investing in better insulation envelope systems for the last decades to reduce the heat transmissions losses and energy consumption in households. LOWTE is a Swedish firm specialized in low energy building components and due to all these facts, it has recently developed a double slot energy active envelope window (EAW) for improving energy-saving in buildings. EAW is a window prototype that integrates low-temperature heating and energy active systems, and it is planned to be installed at Testbed KTH in Stockholm (Sweden). Waste heat from the current heating systems will be used during its whole operation. Then, a life cycle assessment (LCA) will be accomplished for evaluating EAW feasibility and costeffectiveness before its implementation. Furthermore, an LCA comparison with other two passive window systems will be made. A double-glazed and a triple-glazed window will represent the reference system and a competent alternative solution, respectively. A sensitivity analysis for each model will be developed in order to consider multiples scenarios and obtain which variables affect the most EAW profitability. Thus, the feasibility of the EAW would be studied from an economic and environmental perspective. The simulations of both models show the potential that EAW can represent for the current heating system in KTH Live-In-Lab apartments. Since EAW is quite subjected to the thermal conditions of the room, the ambience, and the internal flowing air; costs savings and avoided environmental impacts will depend mainly on the thermal performance of the whole system. / Fönster har alltid betraktats som kylflänsar och de kan stå för mer än 25% av byggnadens kuvert. Av denna anledning spelar deras design och prestanda i bostäder en viktig roll för att reglera inomhusmiljön. Byggsektorn har investerat i bättre isoleringshölje system under de senaste decennierna för att minska värmeöverförings förlusterna och energiförbrukningen i hushållen. LOWTE är ett svenskt företag som är specialiserat på byggnadskomponenter med låg energi och på grund av alla dessa fakta har det nyligen utvecklat ett fönster med dubbelspalt och energi aktivt kuvert (EAW) för att förbättra energibesparing i byggnader. EAW är en fönster prototyp som integrerar låg temperatur värme och energi aktiva system som kommer att installeras på Testbed KTH i Stockholm (Sverige). Avfallsvärme från de nuvarande värmesystemen kommer att användas under hela driften. Sedan kommer en livscykelanalys (LCA) att genomföras för att utvärdera EAW med avseende pågenomförbarhet och kostnadseffektivitet innan denna implementering. Dessutom kommer en LCAjämförelse med andra två passiva fönstersystem att göras. Ett dubbelglasat och ett tredubbelt fönster representerar referenssystemet respektive en kompetent alternativ lösning. En känslighetsanalys för varje modell kommer att utvecklas för att ta hänsyn till flera scenarier och utvärdera vilka variabler som mest påverkar EAW-lönsamhet. Således skulle genomförbarheten för EAW studeras ur ett ekonomiskt och miljömässigt perspektiv. Simuleringarna av båda modellerna visar potentialen som EAW kan representera för det nuvarande värmesystemet i KTHs Live-In-Lab-lägenheter. Eftersom EAW är helt utsatt för de termiska förhållandena i rummet, atmosfären och den inre flödande luften; beror kostnadsbesparingar och minskad miljöpåverkan främst på värmeprestandan för hela systemet.
|
3 |
Gröna bostadsbyggnader : Fastighetsföretags uppfattning av de ekonomiskt positiva faktorerna / Green residential buildings : Realestatecompaniesperceptionoftheeconomically positive factorsGustavsson, Sara, Therese, Jönsson January 2017 (has links)
Gröna byggnader hjälper till att driva den hållbara utvecklingen framåt, vilket behövs inom fastighetsbranschen på grund av dess stora miljöpåverkan. Den fortsatta utvecklingen kännetecknas av problem såsom bristande medvetenhet samt en osäkerhet kring det ekonomiska utfallet. Resultaten som framförs i denna studie bidrar till en ökad förståelse av hur medvetna fastighetsföretag är om gröna bostadsbyggnader samt hur de uppfattar de ekonomiska följderna. Studiens syfte är att belysa hur fastighetsföretag uppfattar de ekonomiskt positiva faktorerna (hyra, vakans, drift- och underhåll, image, inomhusmiljö och risk) som sammankopplas med gröna byggnader. Enbart en del av problemområdet berörs, varvid fokus är på de positiva faktorer som frekvent förekommit i tidigare studier på ämnesområdet. För att besvara syftet har en kvalitativ metod med ett deduktivt ansats valts. Sex fastighetsföretag med varierande miljöengagemang har intervjuats, där samtliga är verksamma i södra Värmland. Intervjufrågorna har baserats på identiskt material för att sedan delvis anpassas efter respektive fastighetsföretag. Resultatet av intervjuerna framkommer i studiens empiriska sammanställning samt analyseras utgående från den teoretiska referensramen. Både likheter och skillnader har observerats. Slutsatsen är att samtliga av de intervjuade fastighetsföretagen värdesätter någon av faktorerna, samt vidrör att ett långsiktigt förhållningssätt är viktigt. Det har framkommit att minskade drifts- och underhållskostnader samt en förbättrad image är de faktorerna som värdesätts högst. Den faktor som företagen anser har minst samband med gröna byggnader är minskad vakans, vilket kan bero på den rådande bostadsbristen. / Green buildings help to drive the sustainable development forward, which is needed in the real estate industry due to its major environmental impact. The continued development is characterized by problems such as a lack of awareness and an uncertainty about the economic outcome. The results presented in this study contributes to an increased understanding of how aware real estate companies are, and how they perceive green residential buildings financial impact. The purpose of this study is to illustrate how real estate companies perceive the economically positive factors (rent, vacancy, operating- and maintenance costs, image, indoor environment and risk) which are linked to green buildings. Only a part of the problem area is examined, whereas focus is going to be on the positive factors which frequently appear in previous studies on the subject area. A qualitative method with an deductive approach has been chosen for this essay in order to answer the purpose of the study. Interviews have been conducted with six real estate companies located in Southern Värmland, whom had varied environmental commitment. The questions that was used have been based on identical material and then been partly adapted after each company. The results from the interviews are stated in the empirical compilation and are being analysed in connection to the theoretical framework. Both similarities and differences have been observed. The concludes are that all of the interviewed real estate companies appreciate some of the factors. All of them mention that a long term approach is of relevance despite their varied startup presumption. It has emerged that the reduced operation- and maintenance cost and an improved image are the most appreciated factors. The factor that the real estate companies consider to have least correlance with green buildings is reduced vacancy, which can be due to the current lack of housing.
|
4 |
Analysis of a novel thermoelectric generator in the built environmentLozano, Adolfo 05 October 2011 (has links)
This study centered on a novel thermoelectric generator (TEG) integrated into the built environment. Designed by Watts Thermoelectric LLC, the TEG is essentially a novel assembly of thermoelectric modules whose required temperature differential is supplied by hot and cold streams of water flowing through the TEG. Per its recommended operating conditions, the TEG nominally generates 83 Watts of electrical power. In its default configuration in the built environment, solar-thermal energy serves as the TEG’s hot stream source and geothermal energy serves as its cold stream source. Two systems-level, thermodynamic analyses were performed, which were based on the TEG’s upcoming characterization testing, scheduled to occur later in 2011 in Detroit, Michigan.
The first analysis considered the TEG coupled with a solar collector system. A numerical model of the coupled system was constructed in order to estimate the system’s annual energetic performance. It was determined numerically that over the course of a sample year, the solar collector system could deliver 39.73 megawatt-hours (MWh) of thermal energy to the TEG. The TEG converted that thermal energy into a net of 266.5 kilowatt-hours of electricity in that year. The second analysis focused on the TEG itself during operation with the purpose of providing a preliminary thermodynamic characterization of the TEG. Using experimental data, this analysis found the TEG’s operating efficiency to be 1.72%.
Next, the annual emissions that would be avoided by implementing the zero-emission TEG were considered. The emission factor of Michigan’s electric grid, RFCM, was calculated to be 0.830 tons of carbon dioxide-equivalent (CO2e) per MWh, and with the TEG’s annual energy output, it was concluded that 0.221 tons CO2e would be avoided each year with the TEG. It is important to note that the TEG can be linearly scaled up by including additional modules. Thus, these benefits can be multiplied through the incorporation of more TEG units.
Finally, the levelized cost of electricity (LCOE) of the TEG integrated into the built environment with the solar-thermal hot source and passive ground-based cold source was considered. The LCOE of the system was estimated to be approximately $8,404/MWh, which is substantially greater than current generation technologies. Note that this calculation was based on one particular configuration with a particular and narrow set of assumptions, and is not intended to be a general conclusion about TEG systems overall. It was concluded that while solar-thermal energy systems can sustain the TEG, they are capital-intensive and therefore not economically suitable for the TEG given the assumptions of this analysis. In the end, because of the large costs associated with the solar-thermal system, waste heat recovery is proposed as a potentially more cost-effective provider of the TEG’s hot stream source. / text
|
Page generated in 0.15 seconds