Amorphous silicon photovoltaic windows intend to not only improve thethermal bridge that windows represent but also to collect energy from theradiation incident on the windows themselves. This kind of windows can beapplied anywhere, however to maximize the benefit these can bring it isrecommended for sun-oriented façades. This research aims to investigate theimpacts that this type of windows can have on the energy performance andthermal comfort of a three-story historical stone building in the cold climateof Sweden using the simulation software IDA ICE. The model used for thesimulations had previously been developed and tested in other researches thatinvolved this same building. This research shows that the yearly energyconsumption for the townhall can be reduced down to 280000 kWh,representing a reduction of 5000 kWh compared to the base model, if theHigh transparency windows are applied, representing a reduction of 1,7%.The use of any of the four proposed windows has shown to increase thepercentage of best comfort hours by at least 5% and lowers the percentage ofunacceptable comfort hours at least by a 10%, even having cases with 0 hoursat this comfort level. The upper level of the South façade would be able toprovide the building with 800 kWh yearly, being the level with the highestenergy collection due to having more windows. Approximately every windowcould collect around 90 kWh yearly, which represents 20% of what a solarpanel of the same area correctly oriented could obtain in the same period oftime. Thus, the amorphous silicon photovoltaic windows do not seem to bethe best change despite offering a very promising thermal comfort. Theeconomical viability of this project is what prevents it from being feasiblesince the energy saving/obtaining characteristics are not of great magnitude.

This study looks at how reversible windows can minimize cooling and heating energy use while maintaining thermal comfort in buildings in Sweden and Spain. The growing need for energy-efficient structures and the potential advantages of reversible windows served as the driving forces behind this study. The approach taken in this study is a comparison of energy use of buildings where reversible windows were installed. The windowpanes had properties such that different solar heat transmittance coefficients were attained at the two states of the windows, being altered in spring and autumn. The windows were tested in two different buildings, one in each country, using IDA-ICE software in order to calculate the energy consumption both in winter and cooling, focusing in heating in winter and cooling in summer in order to know if there was a real energy saving compared to the base model used.The major findings indicate that reversible windows significantly reduce cooling and heating energy usage while maintaining thermal comfort levels that are on par with those of traditional windows in buildings. The effectiveness of reversible windows may, however, fluctuate throughout nations, depending on elements including climate, building design, and user behavior. Among themain findings of the study, the ones to be mentioned would be the total energy use reduction in the whole year that add up to 15 % in Sweden and 21 % in Spain and that most of the energy savings came in Summer for both Spain and Sweden. Additionally, the study also made findings regarding the role that awnings play in energy usage, determining that they may be truly significant in terms of reducing electricity bills. The awnings helped reduced the amount of energy used for both climates, in Madrid, the reduction was of 8 % , and in Stockholm it was of 4 % , these findings lead us to believe that the awnings are better suited to warmer climates. This study also investigates the economic viability of this novel kind of windows. The idea was to calculate the extra cost that could be associated to the installation of these newer reversible windows technologies by use of the NPV method to calculate the present value of the future energy savings to know if the money investment of the reversible windows is profitable or not. When comparing the reversible window to the base window both of which share the same U-value an extra 19 % of the base window installation cost could be associated to the new installation of reversible windows (for a 30-year period) for Stockholm, and a 25 % for Madrid. Changing already existing 2-pane windows of ordinary, less insulating quality for the reversible windows, the total energy use is reduced by about 50 % in Spain and in Sweden, but it seems that is just economical for the Swedish model, regarding the well-insulated buildings. An additional conclusion is that, compared to investing in reversible windows on all façades, an investment in reversible windows only on the Southern façade and base windows on the rest becomes a bit more economical, with 25 % allowed extra cost for the reversible windows in Stockholm climate and 27 % in Madrid; however clearly less energy is saved.According to the study’s findings, reversible windows have proven to be useful tools to reduce energy usage in both climates and locations. Meaning that they may play an important role to reduce the impact of the energy crisis that affects the current situation.Reversible windows can lower a building's energy costs and carbon footprint, which can have good economic and environmental effects. For architects, builders, and legislators interested in promoting energy-efficient buildings, the study's findings may be helpful. Reversible windows are highlighted in this research as a viable solution to lower energy use and enhance thermal comfort in buildings, particularly in areas with large temperature and solar radiation changes.

Western Europe Functionalism ideas are born of the need for scientific and technological progress in producing new materials and building technologies.  Today energy efficiency has become one of the most important characteristics of any project, where functionalism reflects well-designed building components. Reducing energy consumption, improving energy efficiency and minimizing greenhouse emission in the building is vital for the planet's survival. This study intends to provide expertise in design and construction disciplines to use the idea concept of Fallingwater and Villa Savoye, functionalist-style buildings, from the golden era of functionalism. This evaluation can help a new generation of designers and architects to improve the passive energy efficiency and daylight of studied concepts, pragmatic and organic. As a case study, the authors simulated and evaluated the energy efficiency of two conventional architecture designs stated above. Energy efficiency and daylight simulation of these functionalist-style buildings were executed using the BIM-based Building Energy Simulation (BES) tool. The indoor temperature variation and the amount of illuminance for each zone were assessed. The result indicates that the main temperature variation (mean air and operative temperature) in both buildings is not suitable for living and some parts of the regularly occupied floor receive too much direct sunlight. Based on the results, some passive energy-saving measures such as improving building orientation, material and shape, window wall ratio (WWR), adding external shading device, window position, and size are suggested to help researchers in the AEC industry in the future reforming process.

The largest contributor to global warming from the construction and real estate sector comes from the emission of greenhouse gases during the production and usage phases of buildings. During production the leading contributor accounting for emissions is material production while the largest impact in the usage phase is due to energy used for heating, where the largest heat losses occur through building envelopes. Therefore, should the material selection for the building envelope be optimized both regarding the materials lifetime pollutant emissions as well as its effect on energy consumption during building use. The purpose of this paper is to review materials carbon footprint regarding its lifecycle and the effect on energy use of different exterior wall constructions during building use. To answer these questions different methods are applied such as case studies, theoretical studies and simulations. Investigated materials and exterior wall constructions are sandwich panels with a core of rock wool, CLT (cross laminated timber) combined with glass wool and CLT combined with hemp fiber insulation. The result of the study indicates that the climate impact from production of the investigated materials is small compared to the climate impact of energy use. However the study shows that the emissions from the production phase differ between materials. CLT combined with hemp fiber insulation or glass wool insulation has less of an effect on greenhouse emissions compared to sandwich panels. Furthermore, depending on the selection of dimensions for CLT and insulation there are possibilities to reduce energy consumption during building use and still maintain a lower level of emission from material production compared to sandwich panels. / Den största klimatpåverkan från bygg- och fastighetssektorn beror idag av växthusgasutsläpp under byggnaders produktionsskede och bruksskede. I produktionsskedet kommer den mest betydande andelen utsläpp från materialproduktion och i bruksskedet från energianvändning som beror av uppvärmning av fastigheter, där de största värmeförlusterna sker genom en byggnads klimatskal. Materialval i klimatskalet bör därför optimeras både med avseende på koldioxidutsläpp under dess livscykel och materialets påverkan på en byggnads energianvändning i bruksskedet (Boverket 2018:5), (Sveriges Byggindustrier 2014). Arbetets syfte är att redogöra för olika byggnadsmaterials klimatpåverkan, både med avseende på materialets livscykel och olika ytterväggskonstruktioners påverkan på energianvändning i byggnadens bruksskede. Målet är att skapa underlag inför val av material i en hallbyggnads klimatskal. Tre frågeställningar har formulerats med syftet i åtanke; Hur påverkas byggnadens energianvändning beroende på val av ytterväggskonstruktion?; Vilken klimatpåverkan har respektive ytterväggskonstruktion, med avseende på produkternas livscykler? och; Vad är byggnadens klimatpåverkan med avseende på materialproduktion och byggnadens energianvändning?. För att svara på frågeställningar tillämpas flera metoder. En fallstudie ger arbetet en utgångspunkt och en litteraturstudie skapar underlag för att analysera material och produkters klimatpåverkan. Utifrån insamlade fakta simuleras aktuell byggnad och given energianvändning kan omvandlas till klimatpåverkan. Material och ytterväggskonstruktioner som undersöks är sandwichpaneler med stenullsisolering, som referenskonstruktion. Vilken jämförs med KL-trä kombinerat med glasullsisolering respektive hampafiberisolering. Valet av studerade material åligger i att forskning visar på att kombinationen av massiva trästommar och isoleringsmaterial i klimatskalet kan bidra till att minska byggnaders energianvändning. Studien visar att klimatpåverkan från tillverkningsskedet för ytterväggarnas material är lågt i jämförelse med klimatpåverkan orsakad av bruksskedets energianvändning. Det framgår emellertid att konstruktionerna sinsemellan skiljer sig åt utsläppsmässigt vid produktion av material. Att använda KL-trä kombinerat med glasullsisolering eller hampafiberisolering ger lägre klimatpåverkan i förhållande till sandwichpanel. Beroende på val av dimensioner av KL-trä och isolering finns också möjlighet till att minska energianvändningen i byggnadens bruksskede och erhålla lägre klimatpåverkan vid materialproduktion i jämförelse med sandwichpaneler.

Buildings play a central role for livability and carbon footprint of urban areas. Ambitious energy saving and emission reduction targets created a need for a new generation of decisionsupport methods and tools that allow for detailed analysis of urban energy on a large scale. Urban building energy modeling (UBEM) that has emerged recently is an efficient approach to assess energy performance of multiple buildings and system effects from urban energy interventions. However, the further upscale of UBEMs is significantly limited due to the lack of automation for building energy performance (BEP) simulations required for such models in large amounts. This thesis aimed to explore challenges for automation of BEP simulations, and to develop a prototype tool that would serve as a middleware between UBEM and BEP simulation engine, focusing on the IDA ICE simulation software. The result of this thesis is icepy — a tool for automation of BEP simulations in IDA ICE. It uses IDA ICE API and Lisp scripting to provide interaction between UBEM process and IDA ICE in order to generate initial simulation model (IDM), execute simulation and manage results in an automated way. Being implemented as a Python package, it allows to modify multiple IDMs or export simulation results with a few lines of code. The developed tool has been tested and validated for the case building in Minneberg, Stockholm. The automation capabilities provided by icepy has allowed to perform sensitivity analysis for building design parameters as was demonstrated for the window-to-wall ratio (WWR) and three various algorithms for window distribution. The resulting tool has limited functionality as it addressed building envelopes which is only one component of building simulation. However, it has proved to be an efficient approach to automate simulation process and has shown a good potential for further development of such tools. / Byggnader spelar en central roll för urbana områdens levbarhet och koldioxidavtryck. Ambitiösa mål för energibesparing och utsläppsminskning har skapat ett behov av en ny generation beslutsstödmetoder och verktyg som möjliggör detaljerad analys av städers energianvändning i stor skala. Urban byggnadsenergimodellering (UBEM) har nyligen utvecklats och är ett effektivt tillvägagångssätt för att bedöma energiprestanda för flera byggnader och systemeffekter för olika energiåtgärder inom den urban miljön. Den ytterligare uppskalningen av UBEM är dock begränsad på grund av bristen på automation av simulering som är inriktade på byggnadsenergiprestanda (BEP), vilket krävs för att hantera stora byggnadsbestånd. Det här examensarbetet syftar till att utforska utmaningar med automatisering av BEP-simuleringar och att utveckla en prototyp som ska fungera som en mellanprogramvara mellan UBEM och BEP-simuleringsmotorer, med fokus på IDA ICE(som är en simuleringsprogramvara). Resultatet av examensarbetet är icepy, som är ett verktyg för att automatisera BEP-simuleringar i IDA-ICE. Icepy använder IDA ICE API och Lispskript för att tillhandahålla interaktion mellan UBEM-processen och IDA ICE för att generera en initial simuleringsmodell (IDM), utför själva simuleringen och slutligen hanterar resultatet på ett automatiserat sätt. Genom att icepy implementeras som ett Pythonpaket kan den modifiera flera IDM:er och även exportera simuleringsresultat med några få kodrader. Området Minneberg i Stockholm har använts i en fallstudie för att validera och testa verktyget. Automatiseringsfunktionerna i icepy har möjliggjort känslighetsanalyser för olika byggnadsdesignparametrar, exempelvis studerades påverkan av olika värden på förhållandet mellan fönster och väggar genom användning av tre olika algoritmer för fönsterdistributioner. Det utvecklade verktyget har begränsningar i funktionalitet framförallt på grund av att enbart byggnadens ytterskal studerades i byggnadsenergisimuleringarna. Verktyget har dock visat sig vara ett effektivt tillvägagångssätt för att automatisera simuleringsprocesser, vilket visar på en god potential att också vidareutveckla dessa verktyg.

The Swedish residential sector uses 140 TWh of energy, making the residential sector the largest energy user. The Swedish single-family houses (SFHs) are responsible for 12 % of the final energy use. From those dwellings, there are 417 909 single-family houses built before 1930.On the basis of the above information, the Swedish residential building stock is considered to be of relatively high age. Due to this situation, there is a great potential for the implementation of energy saving measures. This work consists in a study case of a single-family house (SFH) built in Stråtjära which uses electricity and wood as energy carrier, the aim in this dwelling is to propose measures to reduce energy expenditure proposing cost-effective measures and reaching a minimum label of bronze category in the Miljöbyggnad energy use indicators. At first, a literature review was performed to observe the renovation strategies previously applied in similar studies. A quantitative and empirical approach was completed, where energy data from the bills of 2023-2024 together with on-site data collection were combined as a way to determine the energy entering and leaving the dwelling. The research was conducted with the help of the IDA ICE energy simulation program, to monitor the energy and ventilation performance of the dwelling. The results obtained from the simulation and hand calculations indicated that there was room to improve the property. Namely, the calculations concluded that the ventilation and the primary energy number need to be improved to meet the Swedish building regulations. Furthermore, the installation of photovoltaic (PV) modules to meet part of the electricity demand could helped to improve the energy situation. Finally, the reduction of electricity use was focused on the efficient use of electricity, avoiding the electricity consumption in unused rooms, such as the guest room, and the reduction of heat/thermal losses through the insulation of the envelop. The methodology used consisted of two different scenarios, one that meets the objectives of monetary savings and economic viability and the other that seeks to comply with the requirements imposed by the Swedish authorities in terms of energy efficiency.

Low-emissivity (low-E) window films are designed to improve the energy performance of windows and prevent indoor overheating by solar radiation. These films can be applied to different types of glazing units without the need for changing the whole window. This characteristic offers the possibility to improve the energy performance of the window of old and historic buildings for which preservation regulations say windows should remain more or less unchanged. This research aims to figure out to what extent a low-E window film can improve thermal comfort and energy performance of an old three-storey historic stone building in the cold climate of Mid-Sweden. In this research, first, with help of the simulation software “IDA ICE”, the entire building was modelled without window films in a one-year simulation. Second step was to add the low-E window films (3M Thinsulate Climate Control 75 (CC75)) to all the windows and repeat the simulation. Comparison between the results of the two cases revealed an improvement in energy use reduction as well as the thermal comfort when applying the films. For the application of the window films, a cost analysis using payback method was carried out which showed a long- time payback period. Although an investment with a long-time payback period is considered as a disadvantage, for historic buildings with very strict retrofit regulations specially when it comes to the building’s facades, application of the low-emissivity window films for better energy performance and thermal comfort is among the recommendable measures, but not necessarily the best.

Syftet med detta examensarbete har främst varit att förbättra inomhusklimatet i byggnaden Greenhouse, tillhörande företaget IVT Värmepumpar i Tranås. De anställda upplever problem med värme i byggnadens utbildningslokaler främst under sommarhalvåret. Tid har även lagts på att ta fram åtgärder som sänker byggnadens energianvändning i form av el och värme. Då examensarbetet utfördes under hösten användes ett simuleringsprogram för att få en bild av inomhusklimatet under sommarhalvåret. En modell av byggnaden byggdes upp i simulationsprogrammet, komplett med ventilations- och värmesystem. För att validera modellen som konstruerats utfördes flertalet mätningar under en veckas tid. Simuleringsmodellen kalibrerades sedan mot dessa mätningar för att efterlikna de verkliga förhållandena i så stor mån som möjligt. När modellen överrensstämde mot mätningarna utfördes simuleringar under sommarhalvåret för att få en bild över inomhusklimatet och för att påvisa eventuella problem. Två olika scenarier under sommaren konstruerades med olika värmelaster och tidscheman. Scenario 1 testade hur inomhusklimatet påverkades av en stor värmelast i bara en utbildningslokal och scenario 2 behandlade en relativt stor värmelast i alla utbildningslokaler. Resultatet från simuleringarna visade på problem med värme i lokalerna, dock inte i samma utsträckning som de anställda upplever. Efter analys av inomhusklimatet och ventilations- och värmesystem togs flertalet åtgärdsförslag fram. De flesta åtgärdsförslag implementerades i simuleringsmodellen för att se vilken potential åtgärden har och se deras effekt under sommarhalvåret. Åtgärdsförslagen har antingen som mål att förbättra inomhusklimatet eller sänka energianvändningen. Nedan i Tabell 1 presenteras dessa förslag (ej inkluderad här, se istället själva rapporten), vissa förslag har även en uppskattad besparingspotential för byggnadens värmebehov och ventilationsaggregatets elförbrukning per år. Då detta examensarbete eventuellt inte löser det värmeproblem som finns i byggnaden föreslås även vidare åtgärder som kan behöva vidtas för att komma närmare en lösning på problemet. / The purpose of this thesis has primarily been to improve the indoor climate in the building Greenhouse, belonging to the company IVT Värmepumpar in Tranås. The employees are experiencing problems with heat in the building's training facilities, specifically in the summer. An effort has also been made to develop measures that reduce building energy use in the form of electricity and heat. As the thesis was conducted during the autumn a simulation program was used to obtain a picture of the indoor climate during the summer. A model of the building was constructed in the simulation program, complete with ventilation and heating systems. To validate the model constructed, several measurements were taken during one week. The simulation model was calibrated against these measurements to mimic reality as much as possible. When the model was consistent with the measurements, simulations were performed in the summer to get a picture of the indoor climate and to detect any problems.   Two different scenarios during the summer were constructed with different heat loads and time schedules. Scenario 1 tested how the indoor climate was affected by a large heat load in only one training facility, and, scenario 2 tested how the indoor climate was affected by a relatively large heat load in all training facilities. The results from the simulations showed problems with heat in the premises, albeit not to the extent of the employees previously stated experience. After analysis of the indoor climate, ventilation and heating systems, several actions were proposed. Most of these actions were implemented in the simulation model to see their potential and their effects in the summer. These proposals are either committed to improving the indoor climate or to reduce energy usage. These proposals are presented in Table 1 below (not included here, see the actual report) ; some proposals also have an estimated savings potential for total heating and the air handling unit’s electricity usage per year. Since this thesis might not solve the heat problems in the building, this report also includes suggestions on measures that may be required to reach a solution to the problem.

Uppvärmningen av ett småbostadshus står vanligen för kring hälften av dess energianvändning. Enligt energimyndigheten drar det svenska standardhuset 22,7 MWh per år varav 12,2 MWh går till uppvärmning. Att ge värmesystemet så bra förutsättningar som möjligt bör alltså vara av intresse för varje husägare, kanske främst ur ett ekonomiskt perspektiv men även ur ett ekologiskt perspektiv. I detta arbete har olika energieffektiviseringsåtgärder studerats som kan implementeras i en tvåplansvillas värmesystem bestående av en värmepump, golvvärme på nedervåningen och olika värmedistributionssystem på övervåningen. Åtgärderna har innefattat både praktiska såsom val av isolering i golvvärmesammanhang och mer teoretiska såsom reglerstrategier. Relevant teori för de ingående systemen har presenterats och utgjort grunden för implementeringar av systemen i simuleringsprogrammet IDA Indoor Climate and Energy. Programmet har använts för att simulera en modellbyggnad utrustad med de olika systemlösningarna varvid resultaten sedan jämförts mot varandra. Det mest energieffektiva systemet på övervåningen har visat sig vara lågtempererade radiatorer tack vare kombinationen med golvvärme på nedervåningen vilket tillåter värmepumpen att arbeta med en lägre värmekurva. Även då golvvärme på övervåningen användes erhölls en låg energiförbrukningen, dock på bekostnad av komforten. Elradiatorer, vilka inte kan utnyttja energin som värmepumpen hämtar ur värmekällan, gav den högsta energiförbrukningen. / Heating of a single family residence usually constitutes about half of the total energy consumption. According to Energimyndigheten, the average Swedish house consumes 22,7 MWh whereof 12,2 MWh goes to heating. To bring about as good conditions for the heating system as possible should be of interest for every house owner, maybe mostly out of an economic point of view but also out of an ecologic point of view. This work have studied different efforts aiming towards a more energy efficient system that can be implemented in the heating system of a two story single-family house equipped with a heat pump, floor heating on the first floor and different heat distribution systems on the second floor. The different efforts include both practical such as choice of insulation in relation to floor heating and more theoretical such as control strategies. Relevant theory for the different subsystems has been presented and used for implementation in the simulation software IDA Indoor Climate and Energy. The program was used to simulate a building model equipped with the different heating systems in which the results are compared to each other. The most energy efficient system on the second floor proved to be low temperature radiators due to the combination with the floor heating system on the first floor which allows the heat pump to operate with a lower heating curve. Although floor heating on the second floor also yielded a low energy consumption, it was at the expense of comfort. Electric radiators, which cannot take advantage of the energy the heat pump collects from the heat source, yielded the highest energy consumption.

Climate change and energy efficiency has become a matter of concern in recent times; therefore, energy efficiency of buildings has drawn major attention. According to the European Commission, EU countries must improve energy efficiency of existing buildings by retrofitting and renovating the buildings. A case study of a renovated commercial building is considered in this degree project. A model of the building is developed in the IDA Indoor Climate and Energy (IDA ICE) software. The model is then augmented to include renovations in the building. Further, the model is simulated in IDA ICE before and after renovations to investigate the impact of renovations on energy consumption of the building for one year. The simulation results indicate peak demands of district heating that occur in the coldest days of the year. The peak demands of energy are expected to increase the district heating cost because they serve as a basis for new pricing model introduced by the energy providers. Hence, it is important from the customer point of view to reduce the peak loads for cost shavings. The project work also provides an insight into the alternative source of energy such as heat pumps to reduce the peak load demands of district heating.