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• 1.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Optimization of Energy Supply Systems for a Sustainable District in Stockholm Using Genetic Algorithms2014Inngår i: Proceedings of the World Sustainable Buildings Conference 2014, 2014Konferansepaper (Fagfellevurdert)
• 2.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Värmelaster i laboratorium: Undersökning av laboratorieutrustnings värmeavgivning2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Byggnader med laboratorier är ofta mer utrustningstunga och därmed blir de större förbrukare av energi än vanliga kontorsbyggnader. Med stor mängd utrustning och med utrustning som dessutom kan ha en hög effektförbrukning kommer det stora värmelaster till rummet som behöver kylas bort och detta behov av kyla måste fastställas under projekteringsfasen av ett byggprojekt. En utmaning som man ställs inför vid projektering av kylsystem är att göra en bedömning för hur stora de interna värmelasterna är från den elektroniska utrustningen som finns i rummen. I många fall gör man en bedömning genom att använda schablonvärden för de interna lasterna då det tidigt i projektet inte är fastlagt vad för typ av utrustning som kommer att placeras i rummen och i vilken utsträckning utrustningen kommer att användas. Denna uppskattning av interna värmelaster blir i många fall felaktigt bedömd. Vid projektering av laboratorier är utmaningen ännu större då byggprojekt med laboratorier är få vilket innebär att det finns mindre erfarenhet och kunskap att kunna göra en välgrundad bedömning. Detta leder till att laboratorier i många fall har system för kyla som är överdimensionerade vilket leder till onödigt höga investeringskostnader, ineffektiva installationer och högre driftkostnader.

Syftet med detta examensarbete har varit att ge bättre underlag för framtida projekteringar av laboratorier genom att undersöka hur väl utrustningstillverkarnas angivelser för märkeffekten stämmer överens med den verkliga effektförbrukningen. Arbetet har även försökt visa på hur ofta och i vilken omfattning utrustningen används genom att studera en utvald laboratoriebyggnad vid Karolinska Institutet. Detta har gjorts genom att anta att all effekt som utrustningen förbrukar omvandlas till värme och tillförs till rummet. Genom detta antagande har värmeavgivningen kunnat bestämmas genom att mäta och logga elförbrukningen under en veckas tid med hjälp av en eleffektsmätare.

I detta arbete gjordes det mätningar på åtta stycken utrustningstyper och resultatet i arbetet visar att användningsdiversiteten för all utrustning som det gjordes mätningar på är 43 %. Delar man upp utrustningen utefter märkeffekt över och under 1000 W blir användningsdiversiteten 4 % för det förstnämnda samt 53 % för det sistnämnda. Ismaskinen och skakinkubator hade 65 % av den totala förbrukningen under mätperioderna och var med det de överlägset största förbrukarna i mätningarna. Av de utrustningar som har intermittent användningsmönster var det de mikrobiologiska säkerhetsbänkarna samt skakinkubatorn som hade mest tid i aktivt läge.

Jämför man med mätdata som finns för laboratorieutrustning på Labs21 Wiki-sida hade utrustning med märkeffekt över 1000 W en genomsnittlig användningsdiversitet som var 50 % och utrustning med märkeffekt under 1000 W en genomsnittlig användningsdiversitet som var 74 %.

Som slutsatserna i detta arbete visar finns det stort utrymme för en förbättrad och mer precis projektering av ett laboratoriums värmelaster. Med en mer precis projektering kommer det dock nya utmaningar såsom riskhantering om ett system istället blir underdimensionerat och möjligheterna för framtida förändringar av ett laboratoriums utrustningar minskar. Fördelarna med ett mer precist kylsystem är många där det finns stor besparingspotential både ekonomiskt och miljömässigt.

• 3.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Calibrating symphonies2016Inngår i: CLIMA 2016 - proceedings of the 12th REHVA World Congress / [ed] Heiselberg, Per Kvols, Aalborg University, Department of Civil Engineering, 2016, Vol. 6, artikkel-id 225Konferansepaper (Fagfellevurdert)

In this paper we address the general topic of calibrating initial Building Energy Performance Simulationmodels, iBEPS. We build upon a recently published paper entitled “Narrowing the Gap- A Framework for Connecting and Auto-Tuning a Design BPS Model to a Physical Building”to outline a methodology for calibrating iBEPS models. We highlight common trends and pitfallsencountered in iBEPS calibration studies, and propose strategies and a methodology for overcomingthese obstacles. The methodology is implemented and tested on IEA Annex 58 single housingmodel.

• 4.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Modelling and Analysis of Daylight, Solar Heat Gains and Thermal Losses to Inform the Early Stage of the Architectural Process2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

The EU building sector is a main contributor to greenhouse gas emissions, which need to be cut as part of the global response to anthropogenic climate change. This cut can be realised through improvements in building energy performance, such as optimisation of facade design. The early stage of the architectural process has been identified as the ideal time to implement such sustainable design choices. There is need for simple guidelines and tools to provide quantitative data to support these architectural decisions. BIM and parametric design can provide this, by facilitating model-based analysis and simulation, as part of an unbroken flow of information through the design process. This study uses Dynamo (the visual programming add-in for Autodesk Revit) together with the Honeybee and Ladybug environmental plugins, to conduct daylight, solar heat gains and thermal losses analyses and simulations. The aim was to identify limitations and opportunities in using Dynamo-Revit, to establish an optimal range for glazing-to-wall ratio (GWR) and to provide some simple room-sizing guidelines for architects in the early stage of the design process. The Dynamo-Revit workflow was found to be effective for specific projects, but difficult to perfect for multiple different projects. An optimal range for GWR was found as 30-40% for east, south and west-facing rooms and around 50% for rooms facing only north. Results were tabulated, linking room orientation and depth with estimated daylight access, solar heat gains and thermal losses. The results were reasonable, but could be improved by the use of more sophisticated analysis and simulation techniques, which should be facilitated by forthcoming development of Honeybee and Ladybug in Dynamo.

• 5.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Assessing the Thermal Performance of Glazed Curtain Wall Systems: S+G Project Case Study2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

The improvement of curtain wall thermal performances and the optimisation of the issues connected with this technology can lead to a sensible reduction of the energy consumption of the building as well as to an increase level of occupant comfort and longer durability of the façade.

The aim of this work is to improve the curtain wall technology especially as far as the connection between the glass and the frame is concerned, since it is the part that mainly affects the performances of the whole façade. This project focuses on the different aspects of the thermal performance of curtain wall systems in order to achieve a higher thermal performance, meeting the objectives of lowering energy demand, improving durability and enhancing indoor comfort.

In order to develop new high performance curtain wall connections and to test their level of performance compared with the state of the art ones, two methods were deployed: a numerical and an experimental one. FEM analysis was performed with the software THERM (LBNL) analysing the profile of surface temperatures and the U-values of the details. In the FEM analysis, different materials and geometries were studied. The experimental characterisation of the thermal energy performance of the studied design options was performed by means of thermometric measurements in a climatic cell. The purpose of the experimental analysis was the verification of the effective improvement of the performance in the new details and the comparison with the simulation, aiming at the validation of the simulation model.

• 6.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Daylight Optimization - A Parametric Study of Atrium Design: Early Stage Design Guidelines of Atria for Optimization of Daylight Autonomy2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

This thesis investigates the design of atria for daylighting in large scale buildings. Athree dimensional test building with a central atrium was constructed and various parameters of the atrium altered. The impact of these changes was studied through computer simulations of annual daylight distribution by implementing state of theart software. Daylight autonomy is simulated for an annual climate file for Stockholm, Sweden.

In the thesis, notion is made of basic daylighting concepts, the importance of bringing daylight into buildings is argued, and the daylighting criteria of three environmental certification tools introduced.

Furthermore, a detailed comparison is made on several well known daylight simulation tools. A newly developed, state of the art, daylight simulation tool called Honeybee, is used in the simulation process. The tool utilizes the calculation engines of wellknown daylight simulation software Radiance and Daysim, which apply backward ray-tracing to reach accurate results. Honeybee is coupled to the graphical algorithmeditor Grasshopper for Rhinoceros 3D, which allows for an efficient way of parametric modelling. The comparison of five different daylight simulation tools showed that Honeybee outweighs the capabilities of many of them by offering a wast range of simulation capabilities and also giving the user exceptional control of result data within multiple zones of the test building.

The results of the daylight study have been compiled into a document which purpose is to serve as early stage design guidelines of atria for architects.

Many factors have been shown through simulation to have a dramatic impact on daylighton an annual basis, and several suggestions have been made on how to maximize the quantity of daylight within buildings containing atria.

• 7.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Characterization of greywater heat exchangers and the potential of implementation for energy savings2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Buildings account for up to 32% of the total energy use in different countries. Directives from the European Union have pointed out the importance of increasing energy efficiency in buildings. New regulation in countries like Sweden establishes that new buildings should fulfill regulations of Nearly Zero Energy Buildings (NZEB), opening an opportunity for new technologies to achieve these goals. Almost 80-90% of the energy in domestic hot water use is wasted from different applications with almost no use and with a lot of potential energy to be recovered.

The present work studied the characteristics of greywater heat exchanger as a solution to recuperate heat from greywater to increase efficiency in buildings. This study explored the fluid mechanics involved in the vertical greywater heat exchangers, analyzing the falling film effect present in drain pipes and the effects of the secondary flow generated in the external helical coil. A heat transfer model from a theoretical approach was proposed and validated. In addition, this study explored the different variables influencing the economic feasibility of the technology and an economic analysis was performed. A theoretical comparison between a greywater heat exchanger application and a reference case without it was evaluated highlighting the importance of all the variables involved in the potential of implementation of the technology. The technology shows big potential in households with high water consumptions, especially with electric boilers.

• 8.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Investigating The Relationship Between Mean Radiant Temperature (MRT) And Predicted Mean Vote (PMV): A case study in a University building2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

No conclusions could be made in terms of ankle draft discomfort due to experimental limitations and more research would be required to investigate this phenomenon.

• 9.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. Högskolan Dalarna.
Högskolan Dalarna. Högskolan Dalarna. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Techno-economic analysis of three HVAC retrofitting options2014Konferansepaper (Fagfellevurdert)

Accounting for around 40% of the total final energy consumption, the building stock is an important area of focus on the way to reaching the energy goals set for the European Union. The relatively small share of new buildings makes renovation of existing buildings possibly the most feasible way of improving the overall energy performance of the building stock. This of course involves improvements on the climate shell, for example by additional insulation or change of window glazing, but also installation of new heating systems, to increase the energy efficiency and to fit the new heat load after renovation. In the choice of systems for heating, ventilation and air conditioning (HVAC), it is important to consider their performance for space heating as well as for domestic hot water (DHW), especially for a renovated house where the DHW share of the total heating consumption is larger.

The present study treats the retrofitting of a generic single family house, which was defined as a reference building in a European energy renovation project. Three HVAC retrofitting options were compared from a techno-economic point of view: A) Air-to-water heat pump (AWHP) and mechanical ventilation with heat recovery (MVHR), B) Exhaust air heat pump (EAHP) with low-temperature ventilation radiators, and C) Gas boiler and ventilation with MVHR. The systems were simulated for houses with two levels of heating demand and four different locations: Stockholm, Gdansk, Stuttgart and London. They were then evaluated by means of life cycle cost (LCC) and primary energy consumption. Dynamic simulations were done in TRNSYS 17.

In most cases, system C with gas boiler and MVHR was found to be the cheapest retrofitting option from a life cycle perspective. The advantage over the heat pump systems was particularly clear for a house in Germany, due to the large discrepancy between national prices of natural gas and electricity. In Sweden, where the price difference is much smaller, the heat pump systems had almost as low or even lower life cycle costs than the gas boiler system. Considering the limited availability of natural gas in Sweden, systems A and B would be the better options. From a primary energy point of view system A was the best option throughout, while system B often had the highest primary energy consumption. The limited capacity of the EAHP forced it to use more auxiliary heating than the other systems did, which lowered its COP. The AWHP managed the DHW load better due to a higher capacity, but had a lower COP than the EAHP in space heating mode. Systems A and C were notably favoured by the air heat recovery, which significantly reduced the heating demand.

It was also seen that the DHW share of the total heating consumption was, as expected, larger for the house with the lower space heating demand. This confirms the supposition that it is important to include DHW in the study of HVAC systems for retrofitting.

• 10.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. Högskolan Dalarna.
University of Innsbruck. Högskolan Dalarna. Högskolan Dalarna. Univeristy of Innsbruck. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Energy performance comparison of three innovative HVAC systems for renovation through dynamic simulation2014Inngår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 82, s. 512-519Artikkel i tidsskrift (Fagfellevurdert)

In this paper, dynamic simulation was used to compare the energy performance of three innovativeHVAC systems: (A) mechanical ventilation with heat recovery (MVHR) and micro heat pump, (B) exhaustventilation with exhaust air-to-water heat pump and ventilation radiators, and (C) exhaust ventilationwith air-to-water heat pump and ventilation radiators, to a reference system: (D) exhaust ventilation withair-to-water heat pump and panel radiators. System A was modelled in MATLAB Simulink and systems Band C in TRNSYS 17. The reference system was modelled in both tools, for comparison between the two.All systems were tested with a model of a renovated single family house for varying U-values, climates,infiltration and ventilation rates.It was found that A was the best system for lower heating demand, while for higher heating demandsystem B would be preferable. System C was better than the reference system, but not as good as A or B.The difference in energy consumption of the reference system was less than 2 kWh/(m2a) betweenSimulink and TRNSYS. This could be explained by the different ways of handling solar gains, but also bythe fact that the TRNSYS systems supplied slightly more than the ideal heating demand.

• 11.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Energy Quality Management for Building Clusters and Districts Using a Multi-Objective Optimization Approach2016Doktoravhandling, med artikler (Annet vitenskapelig)

As society develops, energy needs and the warnings of global warming have become main areas of focus in many areas of human life. One such aspect, the building sector, needs to take responsibility for a significant portion of energy use. Researchers need to concentrate on applying innovative methods for controlling the growth of energy use. Apart from improving energy efficiency by reducing energy use and improving the match between energy supply and demand, energy quality issues have become a key topic of interest. Energy quality management (EQM) is a technique that aims to optimally utilize the exergy content of various renewable energy sources. The evaluation of the optimum energy systems for specific districts is an essential part of EQM.

The optimum energy system must follow the concept of “sustainability.” In other words, the optimization process should select the most suitable energy systems, which fulfill various sustainable requirements such as high energy/exergy performance, low environmental impacts and economic cost, as well as acceptable system reliability. A common approach to dealing with complex criteria involves multi-objective optimization, whereby multi-objective optimization is applied in the context of EQM of building clusters and districts (BCDs). In the present thesis, a multi-objective optimization process is proposed that applies a genetic algorithm (GA) to address non-linear optimization problems. Subsequently, four case studies are used to analyze how the multi-objective optimization process supports EQM of BCDs. Detailed information about these cases is provided below:

1. Basic case (UK): This case is used to investigate the application possibility of the approach in BCD energy system design and to analyze the optimal scenario changes, along with variations of optimization objective combinations. This approach is proven to be time-effective

2. Case 1 (Norway): The use of renewable energy sources can be highly intermittent and dependent on local climatic conditions; therefore, energy system reliability is a key parameter be considered for the renewable energy systems. This section defines system reliability as a constraint function and analyzes the system changes caused by the varying reliability constraints. According to the case, system reliability has been proven to be one of the most important objectives for the optimization of renewable energy systems.

3. Case 2 (China): In this section, the approach is applied in order to search for the optimal hybrid system candidates for a net-zero exergy district (NZEXD) in China. Economic analysis is included in this case study. Through the optimization process, the proposed approach is proven to be flexible and capable of evaluating distinct types of energy scenarios with different objective functions. Moreover, the approach is able to solve practical issues, such as identifying the most feasible options to the stepwise energy system transition for a specific case.

4. Case 3 (China): This section makes two major contributions. The first is to test the expansibility of inserting additional objectives into the approach; a parametric study is then applied to investigate the effects of different energy parameters. The second contribution is the conclusion that the optimum energy systems might vary significantly, depending on certain parameters.

According to the analyses in these case studies, the multi-objective optimization approach is capable of being a tool for future BCDs’ energy system design. It should also be noted that the findings from the case studies – especially the parametric study – might provide some interesting research topics for future work.

• 12.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
A Systematic Approach to Integrated Building Performance Assessment and Visualisation2016Licentiatavhandling, med artikler (Annet vitenskapelig)

The aim of this project was to develop a holistic approach to building-performance assessment without limiting it to energy use (usually expressed in kWh/m2/year), but rather include more parameters that represent the following aspects: Economic, environmental, and quality of service provided to the occupant/client. If it can be shown that buildings can be operated not only in an energy-efficient way, but also in a way that takes into consideration the needs of the occupants, a case could be built that a higher quality of indoor environment does not necessarily mean a higher economic impact. It is also important to show that having access to high-quality building-performance data leads to high-quality analysis and visualisation, and consequently to a chance to detect faults and improve building operation. To answer these questions, a large office building in Stockholm, Sweden was used as a case study. The building was equipped with energy meters and 1,700 sensor points, uniformly distributed over the occupied areas, that measured room temperature, duct temperature, occupancy presence/absence and supply airflow, in addition to other states. The data was processed using RStudio, and various types of visualisation plots were used, including carpet plots, masked scatter plots, bar plots, line graphs, and boxplots. The data pointed to some interesting results. First, just knowing the energy use is not sufficient for understanding the quality of the service provided to the occupants. Second, performing a thorough analysis of room unit data can detect faults. Third, using carpet plots for energy-data visualisation is effective for energy-use pattern recognition. Finally, visualising the building performance parameters in a parallel coordinate plot is a more informative representation of integrated building performance compared to the energy performance certificates typically used today.

• 13.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Occupant Presence Modeling Using Random Forests2016Inngår i: YRSB16 – iiSBE Forum of Young Researchers in Sustainable Building 2016 / [ed] Julie Železná, Petr Hájek, Jan Tywoniak, Antonín Lupíšek, Kateřina Sojková, Czech Technical University in Prague , 2016, s. 188-195Konferansepaper (Annet vitenskapelig)
• 14.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
A Holistic Approach to Building Performance: A Case Study of an Office Building in Sweden2016Inngår i: CLIMA 2016 - proceedings of the 12th REHVA World Congress / [ed] Heiselberg, Per Kvols, Aalborg University, Department of Civil Engineering , 2016, Vol. 6, artikkel-id 246Konferansepaper (Fagfellevurdert)

With the increase of building certification systems worldwide, the evaluation of building performance has been standardized. These certifications provide some points for indoor air quality and thermal comfort in reference to standards like ASHRAE 55 and ISO 7730. However, the assessment is performed taking into account whether the design fulfils the requirements of the standards, in addition to measurements and a survey of the occupants’ thermal comfort (Miljobyggnad Gold). In fact, this only ensures that the requirements are met at the time of the inspection and little is known about the building’s performance after the inspection.In order to analyze the thermal comfort of occupants, a lot of studies have been done applying either the rational or adaptive approach. The rational approach is based on a heat balance model of the human body, while the adaptive approach concentrates on what happens outside controlled environments taking into account the humans’ interaction with their surroundings.This paper presents a new methodology to assess building performance in a holistic manner. The key parameters that are considered include the energy use, the occupants’ thermal comfort, the environmental impact and the corresponding cost. An office building located in Stockholm, Sweden is used as a case study. The energy use is measured through installed energy meters, whereas the thermal comfort is assessed using the degree hours criteria, described in standard EN 15251 (2007).The results allow a better understanding of the correlation between the amount of used energy (kWh per square meter) and the quality of the delivered service. Moreover a long term monitoring of the building leads to a better understanding of how the building should be operated and in some instances to energy savings without compromising on the quality.

• 15.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Long-term performance assessment of autonomous demand controlled ventilation units: A case study of an office building in SwedenInngår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178Artikkel i tidsskrift (Fagfellevurdert)
• 16.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Assessing the impact of the indoor environment on productivity: A case study in a university building in Stockholm2018Independent thesis Advanced level (degree of Master (Two Years)), 300 hpOppgave

The impact that the indoor environment has on productivity is a topic that has been investigated in numerous studies. There are a variety of different methods that have been used to evaluate productivity with. There are quantitative methods and there are qualitative ones, and both have been used in the literature as indicators or real productivity. The quantitative ones are for instance short arithmetical or linguistic performance tests or measurements of the actual quantitative output of a job. Qualitative assessments of productivity consist of different ways of allowing the subjects to rate their own productivity. Both these two approaches of evaluating productivity are claimed to be subject to different issues, and the question of which way is preferable is a matter of contention among the researchers. The quantitative approach is claimed to be unable to reflect the complex and qualitative output of many modern jobs, while the qualitative one is believed to be highly influenced by bias. This master’s degree project has investigated the associations between the two approaches and conducted a qualitative assessment of the impact of the indoor environment on the productivity in a university building in Stockholm.

Numerous studies have been reviewed that include both quantitative evaluations of productivity and qualitative evaluations of the indoor environment. Qualitative evaluations are for instance evaluations of environmental satisfaction, as well as evaluations of healthiness and productivity. The relationship between the quantitative measurements and the subjective evaluation is indeed complex. However, there appears to be a consistency to some extent between the two, and the trend seems to indicate that occupants who are more productive are also more satisfied with the indoor environment or perceive themselves to be healthier or more productive.

A working hypothesis has been formulated; that subjective evaluations of the indoor environment may act as indicators of productivity. This approach has been used in a university building in Stockholm, where the productivity of the students has been evaluated through a survey, together with physical measurements of the indoor environment. The survey is designed based on the current literature within the field. It has a large emphasis on productivity, with several questions concerning it directly and indirectly. The physical parameters that were measured were radiant temperature, air velocity, relative humidity, CO2- concentration and sound pressure level. Considerable correlations were observed between perceived productivity and environmental satisfaction, perceived environmental control and between different ways of evaluating productivity subjectively. The correlations between the physical measurements and the subjective evaluations were in general considerably weaker than the ones between the different subjective parameters. The correlations between the mean CO2-concentration and productivity was weak, and similar findings were obtained concerning sound pressure level. This emphasise the importance of heeding the opinions of the occupants while evaluating the performance of a building, as physical measurements alone appear to be unable to reflect the users’ perspective reliably. The correlation between the thermal parameters (evaluated by the PMV- value) and the subjective evaluations were, on the other hand, considerably stronger. This may indicate that the thermal parameters are among the most influential ones in creating a productive workplace.

Furthermore, the study discusses different methods that have been used to evaluate productivity with. It discusses their weaknesses and strengths and what elements they contain that may be used for future studies of productivity.

• 17. Kilkis, Siir
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Strömnings- och klimatteknik. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Cleaner energy scenarios for building clusters in campus areas based on the Rational Exergy Management Model2017Inngår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 155, s. 72-82Artikkel i tidsskrift (Fagfellevurdert)

Principles based on the quality of energy, namely exergy, can assist in attaining a more efficient and cleaner energy supply structure. This paper analyzes two building clusters in campus areas based on a stepwise approach with four steps according to the Rational Exergy Management Model. The clusters involve 8 buildings at the KTH Royal Institute of Technology and those in the Albano district that is a former industrial site and will become a joint campus area in Stockholm. The energy supply for the campus and urban vicinity includes a combined heat and power plant with district heating and cooling. In this context, the energy and exergy profiles of the building clusters are compared. The level of exergy match in the energy system is analyzed. Four scenarios are then devised, which involve energy savings and different shares of various supply options. These include a new biofuel unit, seawater heat pumps, large scale aquifer thermal energy storage, heat supply from solar collectors, and electricity and heat from photovoltaic thermal arrays. The present case and four scenarios are found to have exergy matches that range between 0.49 and 0.81. The scenarios indicate that savings of 16 GWh energy, 9.6 GWh exergy, and 2663 tonnes of carbon dioxide emissions are possible. The paper contributes to exergy based analyzes for campus areas and concludes with the prospect of using campus areas as pioneering case studies for advancing the transition to cleaner energy scenarios.

• 18. Kilkis, Siir
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Cleaner energy supply structures for campus building clustersManuskript (preprint) (Annet vitenskapelig)

The comparison of building clusters based on energy and the quality of energy (exergy) is a

key aspect for determining steps towards cleaner energy supply structures. This paper

compares two building clusters based on an integrated approach that involves building and

energy system level analyses. The first cluster involves 8 buildings with diverse energy profiles

at the KTH Royal Institute of Technology campus, including faculty buildings, laboratories, and

a data center with waste heat recovery. The second cluster involves planned buildings in the

Albano district in the vicinity of the KTH campus that will be a joint area with lecture buildings

and accommodation for 3 universities in Stockholm. The present energy supply structure for

the campus and the surrounding urban area includes a local combined heat and power (CHP)

plant. The comparison of the building clusters involve analyses based on the Rational Exergy

Management Model. Four scenarios, which involve different shares for the existing CHP units,

new biofuel CHP unit, seawater heat pumps, peak load boilers, electric boilers, large scale

aquifer thermal energy storage, heat supply from solar collectors, and electricity and heat from

photovoltaic thermal arrays are devised for comparison. The scenarios have at most an exergy

match of 0.81. The paper concludes with useful results that are in line with the aims of IEA

Annex 64 on Optimised Performance of Energy Supply Systems with Exergy Principles.

• 19.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
En god natts sömn och återvunnen energi: Modellering av avloppsvärmeväxling på ett stockholmshotell och spa2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

As buildings have become more energy efficient, the energy demand for preparation of domestic hot water stands out as an increasing part of the operational cost and carbon footprint of a building. Most of the heat in the water is used for a short time and then discharged to the main sewer line. Clarion Hotel Stockholm is an example of such a building, with many showers, bathtubs and a spa.

The hotel business is growing around the world and its customers demand comfortable stays. A parallel trend is a more environmentally aware tourism and business travel. Hotels show a great potential for energy savings, while still offering comfortable accommodation. In this master's thesis a case study evaluates the possibilities for heat recovery from the wastewater of Clarion Hotel Stockholm. Three types of heat exchangers were modelled in the system dynamic modelling environment STELLA: a horizontal, a vertical and a shower heat exchanger. Recovered heat was used for pre-heating of the incoming water for domestic hot water preparation. The flows of heat through the hotel's tap water and wastewater systems were schematically modelled using system dynamic modelling, which provides a foundation for the development of mathematical models and further research into the area. The first results point to possible reductions of the heating demand for domestic hot water preparation at Clarion Hotel Stockholm.

• 20.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Evaluation of acoustic, visual and thermal comfort perception of students in the Educational Building at KTH Campus: A study case in a university building in Stockholm2018Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave

In recent years the focus and application of sustainability in buildings has risen. Both for environmental and human well-being reasons. The quality of the indoor environment affects the well-being, productivity and work performance, but it can also affect the occupants negatively, like increasing risks of different diseases and health issues. A good indoor environment alongside with sustainable materials, proper HVAC (Heating, ventilation, and air conditioning) installations and building code regulations contribute to a sustainable solution with low environmental impact and reduced energy consumption. Since buildings alone are responsible for 38% of all human GHG (Greenhouse gas) emissions (Wikipedia, 2017), most countries recommend new more sustainable solutions to reduce that percentage. For example, in the EU, the 2020 climate and energy package targets to: cut 20% in greenhouse gas emissions, 20% of EU energy from renewables and 20% improvement in energy efficiency (European Comission, n.d.).

In addition to the positive aspect of low environmental impact new constructions have, they also create a good living or working environment for the users. Studies have shown that a better indoor quality increases the productivity and work performance, but most of all the occupants feel comfortable and satisfied with their environment. A great number of papers have reviewed the acoustic, visual, thermal comfort and indoor air quality, which are main aspects of the indoor climate. Most papers focus on the users’ perception of these four aspects as well as other parameters that influence the indoor environment (architectural geometry, materials, etc.). Similarly, in this study case I focus on two different methods of obtaining the results, the objective method that contains the indoor environment measurements and the subjective method which includes a questionnaire created specifically for this research project.

By obtaining these two sets of data, key focus points are developed, such as if the building’s certification meets the recommendations of Miljöbyggnad, what aspects influence the students’ perception the most, and whether there are any distinct connections between measured and calculated data. This study case was developed in a university building in Stockholm, where the four main aspects of the indoor environment were evaluated. The physical parameters such as temperature, air velocity, relative humidity, CO2 concentration and acoustics were measured in five different classrooms. In addition, a survey was developed for this study which included perception questions of the thermal, visual, acoustic comfort and indoor air quality. As found in other studies, gender and climate zone origin affected the overall indoor environmental perception. Even though the majority of both genders voted for “no change”, the remaining females answered that they preferred the conditions warmer. Also, the majority of answers from all climate zones were “no change”. However, the second highest opinion for students from warmer climate zones was “warmer”, which has also been found in other studies. Significant negative correlations were found between the acoustics and the satisfaction level of the acoustic comfort. Similarly, high correlations were observed between the visual comfort satisfaction level and the three aspects influencing it. Furthermore, the results showed that all physical measurements influenced the students’ thermal comfort and indoor air quality perception. All measurements obtained indicated a good indoor environment in all classrooms, and all values were between the Swedish Standards recommendations. Low correlation was found between the measured PVM and the AMV from the questionnaires even though all the values were among the limitations.

Lastly, this study reviews methods that could be applied to similar future studies and, discusses what kind of errors to avoid in the future. There is still a lot of research that can be developed in order to gain a deeper understanding of the indoor environment and how humans perceive it.

• 21.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Building certification as a driver in green building design: The holistic apporach of WELL2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Construction industry is based on the evaluation of building environmental impact. The current situation shows buildings reaching high standards in the field of environmental sustainability, but they often neglect occupants' satisfaction. The International Well Building Institute (IWBI) has released a new building standard called WELL, whose aim is to create sustainable buildings paying attention to occupants' health and well-being. The goal of this thesis is to understand what does WELL add to existent building certification systems. There is a large number of certification systems, green codes, green standards and several other kinds of documents that influence the way in which designers think and develop their projects. A research background is carried out to identify their requirements and fields of applicability. The innovative concepts proposed by the IWBI, need to interface with requirements from different regulations or certifications. The gap analysis performed in this work highlights which are the gaps and the overlaps between WELL and Swedish building regulations (BBR), Miljöbyggnad, BREEAM-SE and LEED-IT. The White Arkitekter's office in Stockholm, known as Katsan and certified with Miljöbyggnad Gold, is used as a case study to have a more specific approach to the problem than the general approach provided with the gap analysis. The report shows significant gaps between WELL and the other regulations and certifications, which are reduced when considering the case study. The outcomes for the different standards have been compared and they have evidenced some innovative features present only in WELL. These features answer to the research question and underline what WELL adds to sustainability concepts.

• 22.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Energy retrofit of an office building in Stockholm: feasibility analysis of an EWIS2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

The energy retrofit of existing buildings has always been a challenging task to accomplish. The example of the Swecohuset building, proves how an integrated approach design between architectural and energetic aspects as well as the use of well-known and efficient technologies are key aspects to achieve the energy-saving goal. This work, in the first part describes the Swecohuset retrofit process, along with the reasons behind the choices which have led to the current result of a reduction by 2/3 of the energy need for space conditioning purposes. Then, in the second part, after a brief focus on the passive aspects which characterize the current energy performance of the building, it is carried out a feasibility analysis of an EWIS (external wall insulation system) by studying its interaction with a complex system as an optimization problem, with the main purpose of understanding the basis of the BPO and explore further building potentialities.

• 23.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Inverkan av värmesystem på termisk komfort i ett flerbostadshus med hänsyn till energianvändning2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Inomhusklimatet har en avgörande roll för människans hälsa och välmående då människor befinner sig inomhus i nästan halva sitt liv. Det finns flera aspekter till hur det ska erhållas ett bra inomhusklimat men de mer betydelsefulla aspekterna är både god luftkvalitet och termisk komfort. Samtidigt som innebörden av reducering av energianvändning har en viktig roll i dagens utveckling. Då det ständigt arbetas med att försöka reducera energianvändningen i syfte till att underlätta för miljö- belastningen, väcker det frågor om hur den termiska komforten påverkas av detta.

Rapportens syfte kommer därmed ligga i identifikation av uppvärmningssystem för ett givet flerbostadshus i Stockholmsområdet med fokus på termisk komfort och energianvändning. Utvärderingen baseras på olika typer av inverkan från diverse system som har utförts med beräkningssprogrammet IDA ICE. Ett referensfall för ett flerbostadshus användes som underlag och modellerades enligt A- och K-ritningar samt indata enligt Sveby. Det kommer även att inkludera de miljöcertifieringar som används i störst utsträckning här i Sverige och både ange deras krav gällande den termiska komforten samt respektive fokusområde då olika miljöcertifieringar har olika bedömningskriterier.

Under denna studie visade det sig att det sällan tas hänsyn till den termiska komforten på motsvarande sätt som energianvändningen. Det har även visat sig att i de fall där krav gällande den termiska komforten finns, är den otillräckligt definierad för att ge en god uppfattning av komforten. Kraven tar, med andra ord, inte hänsyn till hur bra ett hus presterar under ett helt år utan fokuserar på ett momentant värde. Till simuleringen gjordes en känslighetsanalys som påvisade vikten och behovet av en tydlig standard för odefinierade variabler för att uttrycka människors bedömning av termisk komfort. Efter samtliga simuleringarna, granskades energiberäkningar efter erhållen granskningsmall från WSP Systems i syfte att utföra en egenkontroll samt ge ett underlag för rimlighetsbedömning.

Från de erhållna resultaten visade det sig att golvvärme och ökad börvärde till 22 °C gav en ökad termisk komfort men samtidigt en ökning i energianvändningen medan FTX-systemet med radiatorer gav upphov till reducerad energianvändning med cirka en tredjedel samt en liten ökning av den termiska komforten. Det visade sig även vara att vid val av FTX-systemet gav högst årlig energibesparing men att det även bör tas hänsyn till installationskostnaderna för FTX-system och golvvärmesystemet till skillnad från om börvärdet ökas till 22 °C. Det blir då en kostnadsfråga och en avgörande parameter för val bland dessa tre systemen.

• 24.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
A study of the design criteria affecting energy demand in new building clusters using fuzzy AHP2013Inngår i: Sustainability in Energy and Buildings: Proceedings of the 4th International Conference in Sustainability in Energy and Buildings (SEB´12), Springer Berlin/Heidelberg, 2013, s. 955-963Konferansepaper (Fagfellevurdert)

The level of concern regarding the total energy consumption in new building clusters/urban districts (BCDs) has increased recently. Rising living standards have led to a significant increase in building energy consumption over the past few decades. Therefore, along with sustainability requirements, it is essential to establish an effective and precise energy demand model for new building clusters/districts. In principle, energy demand in building clusters is hard to plan and pre-calculate because a number of design criteria influence energy performance. Establishing such a model would require a decision-making base, and the present study proposes two methods for achieving this objective. The study uses general survey aims to collect and identify the design criteria that affect the energy demand model and to evaluate the priorities of each criterion using the fuzzy analytical hierarchy process (AHP) method. Four main criteria - location, building design, government and cluster design - are established, along with a total of 13 secondary criteria. The results show that the use of the AHP method can accurately guide the energy demand model and automatically rank significant criteria. The method can provide the weighting value for each criterion as well as the relative ranking for the energy demand building model. According to the sustainability concept, one crucial benefit is an improvement in the energy performance of building clusters/urban districts and a reduction in energy consumption. Another advantage of this methodology is that it can provide accurate energy input for future energy supply system optimisation.

• 25.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. Electric Power Research Institute, Yunnan Electric Power and Research Institute (Group), Kunming, China .
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Transition path towards hybrid systems in China: Obtaining net-zero exergy district using a multi-objective optimization method2014Inngår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 85, s. 524-535Artikkel i tidsskrift (Fagfellevurdert)

A hybrid energy system including both off-site and distributed energy sources, energy conversion technologies and operation methods, is a necessary step on a transition path towards a sustainable energy system. The challenge is to identify such a combination of design options that result in minimum life cycle cost (LCC) and maximum exergy efficiency (EE) at each phase of the transition path. In this paper, a time-effective multi-objective optimization method based on genetic algorithm (GA), is proposed for the transition path problem. The proposed model makes use of a fitness function approach to reduce the model into one objective function and to reduce the computational time. In a case study, the model is applied to a potential net-zero exergy district (NZEXD) in Hangzhou, China. Here, three possible hybrid energy scenarios and three preference treatment strategies are analyzed. The study suggests that the proposed approach is workable for the identification of the most feasible options to be gradually integrated in an NZEXD in a multi-stage process. In the Hangzhou case, with the reduction of investments in distributed energy components and escalating market prices of fossil fuels, distributed energy system (DES) may have more feasibility in the near future.

• 26.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. Key Laboratory of Efficient Utilization of Low and Medium Grade Energy (Tianjin University), China.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Parametric analysis of energy quality management for district in China using multi-objective optimization approach2014Inngår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 87, s. 636-646Artikkel i tidsskrift (Fagfellevurdert)

Due to the increasing energy demands and global warming, energy quality management (EQM) for districts has been getting importance over the last few decades. The evaluation of the optimum energy systems for specific districts is an essential part of EQM. This paper presents a deep analysis of the optimum energy systems for a district sited in China. A multi-objective optimization approach based on Genetic Algorithm (GA) is proposed for the analysis. The optimization process aims to search for the suitable 3E (minimum economic cost and environmental burden as well as maximum efficiency) energy systems. Here, life cycle CO2 equivalent (LCCO2), life cycle cost (LCC) and exergy efficiency (EE) are set as optimization objectives. Then, the optimum energy systems for the Chinese case are presented. The final work is to investigate the effects of different energy parameters. The results show the optimum energy systems might vary significantly depending on some parameters.

• 27.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Retrofitting a Single-family Home with Increased Use of Renewable Energy2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Buildings account for up to 40% of the total energy use in the world. Directives from the European Union have pointed out the significance of increasing the energy efficiency in buildings. New regulation in countries like Sweden has established that new buildings should fulfil regulations of Nearly Zero Energy Buildings (NZEB), providing the opportunity for renewable energy technologies to achieve these goals. In this paper, the retrofitting potential of renewable energy technologies for a single-family home in Sweden was investigated.The present work studied the characteristics of several renewable energy technologies and their applications for a single-family home in Sweden, including biomass, solar photovoltaics, solar thermal, heat pump, and small-scale wind turbine. Three renewable energy technologies (solar thermal, heat pump and small-scale wind turbine) and one renovation method (window) were selected to investigate. The analysis was made of the current energy use and the potential energy (and cost) savings from each retrofitting of these facilities by means of simulation models using IDA ICE software. The study results show that the proposed renewable energy technologies are technically feasible and economically viable as a source of alternative renewable energy in order to produce clean energy and reduce electricity bills for an electric-heated single-family home located in Sweden. Moreover, the combined retrofitting scheme consist of solar thermal system and window renovation was also proposed and explored. As a result the energy performance of the single-family home would satisfy the nearly-zero energy building requirements and thermal comfort could be maintained at an acceptable level.

• 28.
University of Technology, Sydney, Australia.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Multidisciplinary AEC Education Utilising BIM / PLIM Tools and Processes2013Inngår i: IFIP Advances in Information and Communication Technology, 2013, s. 663-674Konferansepaper (Fagfellevurdert)

The construction industry worldwide is moving towards more collaborative working practices, aided by building information modelling (BIM) tools and processes. BIM could be more accurately described as Project Lifecycle Information Management (PLIM). Many firms are claiming to be ‘doing BIM’, but are just scraping the surface in terms of the benefits that can be leveraged from true integrated, collaborative design and construction. New graduates, trained in collaboration and PLIM techniques will be the best people to drive positive change, but current educational models do not tend to provide these skills. This paper describes current worldwide educational trends in collaborative multidisciplinary education, and a proposed framework to assist academics in implementing changes to AEC curricula.

• 29.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Energy retrofit of an office building in Stockholm: energy performance analysis of the cooling system2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

The increasing attention towards energy efficiency issues has triggered an important process involving the renovation of existing buildings and, at the same time, the creation of recognized certifications assuring the quality of the projects. In line with this trend, the Sweco headquarters, an office building characterized by 24700 m2 of floor area and located in Stockholm, was totally retrofitted in 2012 and obtained the Gold rating after being assessed with the Miljöbyggnad certification procedure. The HVAC system was a key element of the retrofit project since one of the final aims was to combine high indoor environment standards with efficient system performances. However, even if the quality of the design is certified, it is possible that, under real operating conditions, complex systems behave differently from the expectations and adjustments are necessary to correct the emerged gap. To achieve this goal, it is essential to identify the points of weakness of the system by carrying out an energy performance analysis, which is the core of this project. In fact, after providing an overview of the building and the retrofit, this work focuses on the analysis of the cooling system installed in the Sweco building and proves the importance of adopting a step-by-step approach to the problem. Therefore, an increasing level of detail characterizes each step of the analysis, whose final aim is to highlight potential aspects to be improved and create a baseline to test possible solutions.

• 30.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Optimization of Energy Systems for a Sustainable District in Stockholm Using Genetic Algorithms: The case of Albano2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Multi-objective optimization tools using genetic algorithms (GAs) are being increasingly used for improving building performances and sustainability. However, few research studies focus on district-scale solutions. In the present project, a multi-objective optimization method using genetic algorithms was applied in order to help decision makers find the optimal energy mix of a district energy system in the preliminary design phase.

A case study consisting of the new campus Albano in Stockholm (comprising lecture buildings and student residences) was used for the analysis. A wide range of energy systems was included as a design variable: wind turbines, solar thermal collectors and photovoltaic cells, ground-source heat pumps, biomass boilers, combined cooling, heating and power, district heating and district cooling. The energy provided by the chosen technologies and the district energy balances are simulated on an annual basis using a steady-state method with an hourly resolution.

Three objectives functions were to be minimized: (1) the life-cycle costs; (2) the greenhouse gas emissions; and (3) the annual non-renewable primary energy consumption of the district. The optimization process was implemented on MOBO, a multi-objective optimization tool based on genetic algorithms.

The findings include understanding the trade-offs among the three objectives and a selection of alternatives of energy supply systems to be further investigated in the detailed design phase.

• 31.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Energirelevanta aspekter inom miljöklassificeringssystemen LEED och BREEAM2011Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave

Sammanfattning

Syftet med denna rapport är att granska skillnaden mellan energikategorierna i miljöcertifieringssystemen LEED och BREEAM. Eftersom amerikanska LEED bygger på det brittiska BREEAM finns det många aspekter som liknar varandra. BREEAM utgår ifrån de nationella standarderna i första hand. Om sådana inte finns är det de europeiska som används. Klassningen av byggnaden visar hur bra byggnaden är jämfört med de krav som finns nationellt. Dessa är i sin tur anpassade till förutsättningarna som finns i landet.

LEED grundar sig istället på kraven som beskrivs utifrån den amerikanska standarden ASHRAE. Dessa krav är inte anpassade till svenska eller europeiska standarder vilket gör det svårt att jämföra rakt av. Detta innebär att kraven som ställs i ASHRAE och LEED är olika svåra att uppfylla då förutsättningarna i länderna är olika. Till exempel tillhör Sverige klimatzon 6, tillsammans med Chile, Ryssland, Kanada och de nordliga delarna i USA. Detta ger olika utgångspunkter för att klara kriterierna då de naturliga förutsättningarna skiljer sig i olika länder.

För att bedöma om en byggnad är energieffektiv behövs någon typ av verktyg för att verifiera byggnaden. För svenska företag som vill visa att de är miljömedvetna och vill ha låga energikostnader behövs någon typ av märkning av byggnaden. Även utländska företag på svenska marknaden letar efter byggnader med bra energieffektivitet som har ett intyg på att byggnaden följer hårda miljö- och byggnationskrav. Det är då en stor fördel att använda stora internationella system som exempelvis LEED och BREEAM som intygar att byggnaden uppfyller de hårda kraven som finns i systemen. Det indikeras med olika certifieringsnivåer beroende på hur väl byggnaden uppfyller kraven.

Respektive systems energikategori anses viktigast i båda systemen och det är framförallt reduceringen av energianvändningen som spelar en avgörande roll, även användandet av förnyelsebar energi är en viktig del. Generellt i båda systemen sker liknande ställningstaganden i de flesta frågorna för att reducera byggnaders påverkan av miljön, genom olika förbättringsåtgärder. Sporren för att göra byggnaden bättre är att minska miljöpåverkan, sänka driftkostnaden, öka trivseln, förbättra driften och att uppnå en hög certifieringsnivå.

Generellt fås en uppfattning av att BREEAM är enklare att använda än LEED, eftersom den utgår från kraven i BBR. Båda systemen räknar ut en procentuell förbättring eller anger att uppställda värden uppfyllts. Exempelvis räknas reduceringen av koldioxid och energieffektivisering ut procentuellt. I LEED ska även ASHRAE användas utöver BBR och beräknar energieffektivisering utifrån reducering av kostnaden i dollar jämfört med referensbyggnaden.

• 32. Olivero, E.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
On key parameters influencing building energy performance2015Inngår i: 14th International Conference of IBPSA - Building Simulation 2015, BS 2015, Conference Proceedings, International Building Performance Simulation Association (IBPSA), 2015, s. 480-487Konferansepaper (Fagfellevurdert)

This paper describes the methodology used for selecting the most influential parameters on the energy performance of a building, using limited computing power. Detailed building energy performance models development and their manual calibration are depicted. Novel interfaces for the connection of a detailed building simulation software with advanced analytics are then presented. After a first screening of the parameters by domain experts, two techniques are deployed on the models to reduce the number of parameters to be considered in an automatic calibration process: boundaries check and Morris method. The methodology is applied on two non-residential buildings. Finally, the study results are presented, providing deep insight on the buildings energy performance and thus setting the basis for automatic model calibration and faults detection.

• 33.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Energy system and service optimization for building clusters of new urban development: Applying multi-objective genetic algorithmsManuskript (preprint) (Annet vitenskapelig)
• 34.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. University of Melbourne.
A Framework for Integrated Energy Systems, Infrastructure, and Services Optimization with Visualization and Simulation Platform for Low-carbon Precincts2013Inngår i: Proceedings of the International Symposium for Next Generation Infrastructure, 1 - 3 October 2013, 2013Konferansepaper (Fagfellevurdert)

The energy informatics can be enhanced to support decision-making, communication and benchmarking of the energy performance both in design and operational phases. To enable engineers, developers and policy-makers to better understand the implications of energy systems and services, computer-generated visualization is a powerful tool to inform a range of technological options and to analyze the effects of energy system strategies. Visualization increases the transparency of results and the understanding of interactions between users and energy systems. This paper presents a novel conceptual framework for integrating energy systems, infrastructure and services optimization with a visualization and simulation platform. It focuses on the development of a tool for low-carbon energy systems and high quality energy services at precinct scale. The paper describes the vision and architectural design for the integrated framework. It is expected to serve as a next generation approach to managing energy services, carbon emissions and efficient resource use in the built environment. This will help to deliver new environmentally sustainable infrastructure and achieve carbon neutrality in urban development.

• 35.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Modeling urban energy flows at macro and district levels: towards a sustainable urban metabolism2015Doktoravhandling, med artikler (Annet vitenskapelig)

The urban sustainability is a growing importance in the built environment research. Urban areas play a key role in planning for sustainable city development. Urbanization has implications for future energy systems and energy-related emissions. The new built environment requires systems that are cost-efficient and have more efficient utilization of energy with a low environmental impact. This can be analyzed and designed with efficient tools for current and future energy systems. The objectives of this dissertation are to examine and analyze the metabolic flows of urban areas, and to develop a methodology for optimization of energy systems and services for the urban district. The dissertation is comprised of two phases and eight appended publications.

In the first phase of this dissertation, the research is emphasized on an in-depth understanding of the complex dynamics of energy utilization in large urban areas. An integrated approach applied in this phase includes the energetic urban metabolism, the long-term energy systems modeling using the Long-range Energy Alternative Planning (LEAP) system, and the Multi-Criteria Decision-Making (MCDM) approach. The urban metabolism approach has been employed to analyze the urban energy flows at macro level. The LEAP model and MCDM approach have been used to develop and evaluate energy scenarios in both demand and supply sides.

In the second phase, the research recognizes the lack of tools that applicable for district energy systems analysis. This phase concentrates on the important role of the district level in urban energy systems. Research methods include the Multi-Objective Optimization using Genetic Algorithms, the carbon budget approach, and the case study method. Research in the second phase is mainly focused on the development of tool for energy systems and services at the district level.

• 36.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
A proposal of urban district carbon budgets for sustainable urban development projects2013Inngår i: Sustainability in Energy and Buildings: Proceedings of the 4th International Conference in Sustainability in Energy and Buildings (SEB´12), Springer Berlin/Heidelberg, 2013, s. 947-954Konferansepaper (Fagfellevurdert)

Energy security and carbon emissions are key issues for policy-makers and research communities worldwide. Climate change mitigation poses many challenges for all levels of society. Energy-related carbon emissions in urban areas have received a great deal of attention. This paper builds on the principle that urban areas are major sources of emissions and play an important role in the carbon cycle. Urban development can serve as a cornerstone for achieving transition towards a sustainable city. This paper proposes and describes a framework for carbon budgets with a focus on urban district level. The urban district carbon budget is a mechanism for embedding long-term total emission restrictions into the urban economy. This paper proposes a proposal of urban district carbon budgets in an effort to provide the figure for emission allowances that can be emitted in a given amount of time. The paper presents a design framework of urban district carbon budgets and discusses the scope and scale of carbon budget allocation approaches. It also examines the emission reduction potential and co-benefits of the proposal.

• 37.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Distributed energy resource systems towards carbon-neutral urban development: A review and applicationManuskript (preprint) (Annet vitenskapelig)
• 38.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Hybrid Ventilation: Simulation of Natural Airflow in a Hybrid Ventilation System2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

This thesis investigates the possibilities of using hybrid ventilation in an office building in Stockholm. The focus is on simulating the natural airflow to find out for which conditions it is sufficient. The thesis is done at White Arkitekter AB in cooperation and under the supervision of environmental specialists working there. A literature study is carried out to study what has been done before in Sweden as well as in other countries. Computer simulations are used to simulate the airflow to examine the conditions and architecture. A synthetic computer model representing a realistic office building is built up as a starting point. The ventilation method for the natural ventilation part is to take air in through the fa\c{c}ade and use the stack effects in an atrium for natural ventilation. By altering the architecture and the sizes of the openings according to the results from the simulations the building is dimensioned and formed to cope with the rules and requirements about the indoor air quality in workplaces. The simulations are done with a multi zone energy performance simulation tool that can simulate airflows and indoor air climate conditions in the zones as well as the energy consumption. Computational fluid dynamics calculations are then used to more closely simulate the conditions within the zones. The results from those simulations suggest that the natural ventilation as a part of a hybrid ventilation works for all the floors of the building for up to 10$\,^{\circ}\mathrm{C}$. The computational fluid dynamics simulations showed that the thermal comfort of all the occupants is fulfilled for these conditions but there is a risk of occupants experiencing draught because of to high velocities in the air especially for the colder outdoor temperatures. For the higher outdoor temperatures the airflow needs to be enforced to ensure sufficient conditions for the occupants and for the colder temperatures mechanical ventilation is needed to decrease heat losses and avoid the risk of draught.

• 39.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
High-Performance Building Design and Decision-Making Support for Architects in the Early Design Phases2013Licentiatavhandling, monografi (Annet vitenskapelig)

Based on the design decision making process from an architect’s point of view, a related literature review, theoretical analyses, and inductive inferences, this thesis proposes a new interpretation of high-performance building (HPB), translates/maps criteria issues related to building environmental assessment (BEA) tools for key design decision making elements, and identifies sources of inspiration for HPB designs. This thesis intends to propose an integrated conceptual model for the design of HPBs to provide direct knowledge-based decision making support to architects in the early design phase. Studies on key design decision making elements, sources of inspiration, and building information modeling are integrated into this genesis of conceptual design.

The concept of the HPB proposed in this thesis emphasizes comprehensive sustainable building performance in environmental, economic, and socio-cultural aspects. The concept takes the view that HPBs should be aesthetically attractive, socio-culturally adapted, safe, healthy, and comfortable, and should operate at a high level of environmental, resource, and economic efficiency throughout their life cycle. This thesis discusses the topics of the necessity, benefits, and design principles of HPBs.

An analysis of the characteristics of BEA tools and HPB design decision making revealed their relationship: the consequence of goals and the mismatch of practices. BEA tools provide the basic information (such as framework, content, evaluation methods, and processes) related to decision making to promote a holistic HPB design at a practical level. However, given the mismatch of practices between BEA tools and HPB design decision making, most such tools are still used for testing and verifying the design results and do not consider the design decision making process. Existing BEA tools primarily guide or indirectly affect the design work but, in practice, play a limited role in directly helping architects make early decisions regarding HPB design.

First, for a detailed comparison, this thesis identified the common criteria issues for the three existing BEA tools: SBTool 2012 (maximum version), LEED NC-v3, and the Chinese Evaluation Standard for Green Building (ESGB). A total of 51 common/similar criteria issues were identified and such issues were found to be primarily allocated in the energy and resources, indoor environmental quality, environmental loads, and site areas. SBTool 2012 contains the widest range and most comprehensive criteria issues of building performance, whereas the LEED NC-v3 and ESGB frameworks poorly cover social- and economic-related issues. Second, this thesis separated the criteria into whether they relate to decision making factors or building performance factors. Third, this thesis mapped HPB criteria issues into HPB

design decision making elements.

This thesis establishes a framework for key design decision elements for Chinese residential buildings by selecting a residential building type in China as a case study for the mapping approach application. The optimum criteria issues for Chinese residential buildings contain 10 primary criteria issues and 35 sub-criteria issues that cover aspects within the entire sustainable performance range and that correspond to key design decision making elements in this framework.

This thesis also proposes two fundamental support approaches to creative design for HPBs: rational technical support and irrational divergent inspirational support. Based on practical design examples, three major types of irrational sources of inspiration in an architect’s design for HPBs have been identified: previous empirics, nature objects and phenomena, and advanced science and technologies.

Finally, a new integrated conceptual model to support an architect’s early design decisions is established based on the BIM platform. The model contains two main aspects of the work: an initial building information model and an optimal building information model for HPBs during the early design stage. This conceptual model is presented as a generic approach that can be customized for different designers and project conditions. The model can also be used as a framework for providing knowledge-based creative support for decision making related to HPB design.

In summary, this thesis intends to provide both a theoretical base and feasible measures for better HPB design and references for developing design decision making support tools for architects to use during the early HPB design process.

• 40.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Northwestern Polytechnical University. Xi'an University of Science and Technology.
Interpretation of Transparency in the Design of Green Office Buildings2013Inngår i: Civil, materials and environmental sciences, Trans Tech Publications Inc., 2013, Vol. 742, s. 131-135Konferansepaper (Fagfellevurdert)

Green buildings have caught increasing attention in the global context. For green office building (GOB), the design should satisfy both the natural and working environmental considerations. Noticing that while a wide range of eco-technologies have been applied in existing GOBs, comparatively less than enough attentions have been put on the art performance of such buildings, this paper introduces and discusses how transparency, as an important visual language in modern architecture, can be used as a tool to bridge and emphasize the inseparable connection between art and technology in the architectural design area. The purpose of this paper is not only to explore and discuss new concepts regarding design of GOBs, but also to provide references for sustainable design in a larger perspective.

• 41.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Northwestern Polytechnical University. Xi'an University of Science and Technology.
The BIM-based Early Design Decision-making Support for Green Office Building2012Inngår i: Huazhong Architecture, ISSN 1003-739X, Vol. 12, s. 45-48Artikkel i tidsskrift (Fagfellevurdert)

Building Information Modeling (BIM) is a booming technological revolution that is anticipated to greatly increase the productivity of the building industry. As a shared building information resource, BIM can provide important support for design decision-making during the whole building life cycle. This paper selects office building as a research prototype, and proposes a BIM-based early design decision-making concept model for the design of green office buildings. The model proposes to combine building environmental assessment tools and BIM software in estimating the potential environmental performance of green office buildings at design stage. It is expected to be a new approach for providing architects with accurate, effective and fast design decision-making support with the purpose to effectively improve the green office building design.

• 42.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. WSP.
Dagsljusfaktorer vid Miljöcertifiering av Byggnader -En jämförelse mellan beräkningar och mätningar.: Daylight factors in the Environmental Certification of buildings-A comparison between Calculations and Measurements.2014Independent thesis Advanced level (degree of Master (Two Years)), 300 hpOppgave
• 43.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Investigations of Flow Patterns in Ventilated Rooms Using Particle Image Velocimetry: Applications in a Scaled Room with Rapidly Varying Inflow and over a Wall-Mounted Radiator2015Doktoravhandling, med artikler (Annet vitenskapelig)

This thesis introduces and describes a new experimental setup for examining the effects of pulsating inflow to a ventilated enclosure. The study aimed to test the hypothesis that a pulsating inflow has potential to improve ventilation quality by reducing the stagnation zones through enhanced mixing. The experimental setup, which was a small-scale, two-dimensional (2D), water-filled room model, was successfully designed and manufactured to be able to capture two-dimensional velocity vectors of the entire field using Particle Image Velocimetry (PIV). Using in-house software, it was possible to conclude that for an increase in pulsation frequency or alternatively in the flow rate, the stagnation zones were reduced in size, the distribution of vortices became more homogeneous over the considered domain, and the number of vortices in all scales had increased. Considering the occupied region, the stagnation zones were moved away in a favorable direction from a mixing point of view. In addition, statistical analysis unveiled that in the far-field occupied region of the room model, stronger eddies were developed that we could expect to give rise to improved mixing. As a fundamental experimental study performed in a 2D, small-scale room model with water as operating fluid, we can logically conclude that the positive effect of enhanced mixing through increasing the flow rate could equally be accomplished through applying a pulsating inflow.

In addition, this thesis introduces and describes an experimental setup for study of air flow over a wall-mounted radiator in a mockup of a real room, which has been successfully designed and manufactured. In this experimental study, the airflow over an electric radiator without forced convection, a common room-heating technique, was measured and visualized using the 2D PIV technique. Surface blackening due to particle deposition calls for monitoring in detail the local climate over a heating radiator. One mechanism causing particle deposition is turbophoresis, which occurs when the flow is turbulent. Because turbulence plays a role in particle deposition, it is important to identify where the laminar flow over radiator becomes turbulent. The results from several visualization techniques and PIV measurements indicated that for a room with typical radiator heating, the flow over the radiator became agitated after a dimensionless length, 5.0–6.25, based on the radiator thickness.

Surface properties are among the influencing factors in particle deposition; therefore, the geometrical properties of different finishing techniques were investigated experimentally using a structured light 3D scanner that revealed differences in roughness among different surface finishing techniques. To investigate the resistance to airflow along the surface and the turbulence generated by the surfaces, we recorded the boundary layer flow over the surfaces in a special flow rig, which revealed that the types of surface finishing methods differed very little in their resistance and therefore their influence on the deposition velocity is probably small.

• 44.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Particle Image Velocimetry Visualization and measurement of Air Flow over a Wall-Mounter RadiatorManuskript (preprint) (Annet vitenskapelig)
• 45.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
PARTICLE IMAGE VELOCIMETRY (PIV) VISUALIZATION OF AIR FLOW OVER A WALL-MOUNTED RADIATOR2014Konferansepaper (Fagfellevurdert)

A common room heating technique is to use a wall-mounted radiator without forced convection. The cold surrounding air passes adjacent to the warm surfaces of the radiator, gets heated, and the buoyancy difference gives this heated air a momentum to rise along the wall surface (as plume) and finally circulate and get mixed into the whole room. The properties of heated plumes are important for assessing the risk of soiling of the wall surfaces through particle deposition driven by thermophoresis and turbophoresis. It is important to identify where there is a transition from laminar to turbulent flow. With the objective to characterize the plume of heated air flow in the vicinity of wall surface, the airflow over the radiator is visualized and measured using the two-dimensional Particle Image Velocimetry (2D PIV) technique. The PIV technique yields two-dimensional vector fields of the flow. The resulted vector maps are size and peak validated and post processed using in house developed software to provide the average streamlines. In the near wall PIV measurements there are practical problems; generating a homogeneous global seeding that makes it possible to study both the plume and the surrounding entrainment region, and optical problems due to strong laser reflection from the wall surface which limits the investigation area. These issues are dealt with in the present study. In addition to visualization with PIV, visualization with a CMOS video camera was also conducted.

• 46.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. KTH/HiG.
HiG.
PIV Study of Ventilation Quality in Certain Occupied Regions of a Two-Dimensional Room Model with Rapidly Varying Flow Rates2013Inngår i: The International Journal of Ventilation, ISSN 1473-3315, E-ISSN 2044-4044, Vol. 12, nr 2, s. 187-194Artikkel i tidsskrift (Fagfellevurdert)

The use of supply jet flows is the most common type of air distribution for general ventilation. Usually the supply flow rate is constant or slowly varying (VAV-systems) to cope with a varying load. A novel air distribution method, with the potential to reduce stagnation and to increase the ventilation efficiency, is to introduce rapid flow variations (pulsations). This paper reports on a fundamental study of this type of air distribution. The purpose of the study was to explore the effect of flow variations on stagnant zones and the levels of the turbulent kinetic energy and the relative turbulence intensity. A small scale room model is used that consists of an enclosure with a ventilation supply at the bottom and an extract at the top of the opposite wall. Water was used as an operating fluid and the model had a design which mainly generated a two-dimensional flow. The size of the model made it possible to investigate the two-dimensional velocity vector field using the Particle Image Velocimetry (PIV) method in regions corresponding to occupied regions. Further post processing was conducted from the resulting vector fields. The comparison between cases of constant inflow and pulsated inflow (flow variations with frequency of 0.5 Hz) was conducted for three domains: two belonging to the far-field occupied zone and one belonging to the near-field, downstream of the supply wall jet.

• 47.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. University of Gävle, Sweden.
Plaster finishes in historical buildings – Measurements of surface structure, roughness parameters and air flow characteristics2013Inngår i: Plaster finishes in historical buildings: Measurements of surface structure, roughness parameters and air flow characteristics / [ed] A. Troi, E. Lucchi, 2013, s. 69-75Konferansepaper (Fagfellevurdert)

Soiling of surfaces in historical buildings by deposition of particles is a common problem.  Minimizing soiling is an important goal for conservation of structures and objects. The surfaces give rise to an interference with the air motions along the surfaces. Properties of surfaces may therefore influence the particle deposition. It is well known that with increasing roughness of the surfaces the particle deposition rate increases. The properties of surfaces in historical buildings are not well documented.  We have investigated samples of surfaces finished by wood float finish, steel float finish and brushed finish. As a reference we have used an MDF board. The geometrical properties of the surfaces have been documented by using the stripe projection method. The resistance to airflow along the surface and the turbulence generated by the surfaces have been investigated by recording the boundary layer flow over the surfaces in a special flow rig. The work reported is part of a project where the process of soiling is studied both in laboratory and in field studies. The air velocity adjacent to the surfaces will be recorded with both PIV (Particle Image Velocimetry) and hot-wire technique. The temperature gradient close to the walls will be recorded with cold-wire technique.

• 48.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem. Building Technology, Högskolan Dalarna (Dalarna University), Falun, Sweden.
Particle image velocimetry visualization and measurement of airflow over a wall-mounted radiator2015Inngår i: The International Journal of Ventilation, ISSN 1473-3315, E-ISSN 2044-4044, Vol. 14, nr 3, s. 289-302Artikkel i tidsskrift (Fagfellevurdert)

A common room-heating technique involves the use of a wall-mounted radiator without forced convection. The cold surrounding air passes adjacent to the warm surfaces of the radiator where it absorbs heat and gains momentum to rise along the wall surface and finally circulate in the entire room. Understanding the properties of heated airflows is important for several purposes. To understand the flow process it is important to identify where the transition from laminar to turbulent flow occurs and to quantify the turbulent fluctuations. With the objective to characterize the airflow in the vicinity of wall surfaces, the local climate over the radiator was visualized and measured using a two-dimensional particle image velocimetry technique. The PIV technique yields 2D vector fields of the flow. The resulting vector maps were properly validated and post-processed using in-house software to provide the average streamlines and other statistical information such as standard deviation, average velocity, and covariance of the entire vector field. The results show that, for a room with a typical heating power, the airflow over the radiator becomes agitated after an ordinate of N = 5 - 6.25 over the radiator upper level, in which N is the dimensionless length based on the thickness of the radiator. Practical problems encountered in near-wall PIV measurements include generating a homogeneous global seeding that makes it possible to study both plume and entraining region, as well as optical problems due to near-surface laser reflection that makes the measurement process more complicated.

• 49. Smedje, G.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
SBS symptoms in relation to dampness and ventilation in inspected single-family houses in Sweden2017Inngår i: International Archives of Occupational and Environmental Health, ISSN 0340-0131, E-ISSN 1432-1246, Vol. 90, nr 7, s. 703-711Artikkel i tidsskrift (Fagfellevurdert)

Purpose: To investigate the relationships between symptoms compatible with the sick building syndrome (SBS) in adults and building dampness and ventilation in single-family houses. Methods: Within the Swedish BETSI study, a national sample of single-family houses were inspected by professional building experts, and adults living in the houses answered a questionnaire on SBS. Relationships between building factors and SBS were analysed using logistic regression. Results: Of the respondents, 23% reported having had weekly SBS symptoms during the last three months. A large proportion of houses exhibited building or construction problems. In total, 40% of houses had dampness problems in the foundation, and this was related to a higher prevalence of both mucous and dermal symptoms, and any SBS symptoms. Furthermore, high air humidity was related to more symptoms, with the relationship with absolute humidity being stronger than that with relative humidity or moisture load. Symptoms were also more prevalent in houses with a high U value, reflecting a poor thermal insulation. Compared to natural ventilation, living in a house with mechanical supply and exhaust ventilation was related to a lower prevalence of general symptoms and any SBS symptoms, but there were only weak associations between measured air exchange rate and symptoms. Conclusions: A large proportion of single-family houses have dampness problems in the foundation, and pollutants may enter the living space of the house and affect the health of the occupants. Furthermore, absolute air humidity should be measured more often in indoor air studies.

• 50.
KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installations- och energisystem.
Projektering av Solceller: En studie av solcellsteknikens tillämpning i byggbranschen2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Solceller har på senare tid blivit allt hetare ämne inom byggbranschen med utveckling som ger allt bättre förutsättningar för dess tillämpning både gällande effektiv användning av solinstrålning och billigare tillverkningsprocess.

Höga koldioxidutsläpp och det faktum att energiresurser som vi idag är beroende av kommer ta slut ställer allt högre krav på att vi som samhälle kan hitta alternativa hållbara lösningar. Solceller har stor potential för detta då de möjliggör egen lokal elförsörjning för byggnader vilket inte bara skapar trygghet för fastighetsägaren som kan nyttja den i princip oändliga energikällan solen vilket sker utan koldioxidutsläpp förutsatt att produktion av solceller sker från en förnyelsebar energikälla, det möjliggör även elproduktion i städer och andra områden närmare elanvändningen än hur det traditionellt sker idag. Denna potential ger upphov till två viktiga frågor, hur solceller påverkar ekonomin samt hur det påverkar miljön. För att lösningen skall vara attraktiv krävs att den ger utdelning både ekonomiskt och med miljöpoäng för att bidra till företagets miljöprofil.

Följande arbete studerar tillämpningen av solceller i byggbranschen med fokus på ekonomi och process. Två referensobjekt ligger till grund för arbetet, Norra 2 för bostadshus och Torsplan för kontor, som används för att ta fram en resultatkalkyl för typbyggnad kontor och bostad.

Studien baseras på ekonomiska modeller som livscykelkostnad, internränta, nettonuvärde, annuitet, återbetalningstid och s.k. levelized cost of energy. En viktig del av ekonomi för solceller i Sverige är att beräkna hur stor del av den producerade elen som kan användas direkt i byggnaden, detta eftersom det kan vara stor prisskillnad på den använda elen och den som skickas ut som överskott på elnätet, det har därför gjorts en jämförelse på timbasis mellan användningsprofiler och den momentant producerade elen för att uppskatta lönsamheteten för planerad solcellsanläggning. Hänsyn tas även till lagar och regler som gäller i Sverige och hur användning av solceller ger poäng inom de olika miljöcertifieringssystemen LEED, BREEAM, Miljöbyggnad, Svanen och GreenBuilding.

Resultatet av arbetet är ett projekteringsförslag för användning av solceller på referensobjekten Torsplan och Norra 2 vilket används för att analysera de tre grundfrågorna till arbetet:

• Påverkar elanvändning i byggnaden optimal riktning för solcellsinstallation
• Hur kan man utvärdera investering av solceller och hitta lönsamheten
• Är solceller en hållbar lösning i dagens samhälle
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