Techno-economic analysis of three HVAC retrofitting options

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.

A Microdata Analysis Approach to Transport Infrastructure Maintenance

Maintenance of transport infrastructure assets is widely advocated as the key in minimizing current and future costs of the transportation network. While effective maintenance decisions are often a result of engineering skills and practical knowledge, efficient decisions must also account for the net result over an asset's life-cycle. One essential aspect in the long term perspective of transport infrastructure maintenance is to proactively estimate maintenance needs. In dealing with immediate maintenance actions, support tools that can prioritize potential maintenance candidates are important to obtain an efficient maintenance strategy. This dissertation consists of five individual research papers presenting a microdata analysis approach to transport infrastructure maintenance. Microdata analysis is a multidisciplinary field in which large quantities of data is collected, analyzed, and interpreted to improve decision-making. Increased access to transport infrastructure data enables a deeper understanding of causal effects and a possibility to make predictions of future outcomes. The microdata analysis approach covers the complete process from data collection to actual decisions and is therefore well suited for the task of improving efficiency in transport infrastructure maintenance. Statistical modeling was the selected analysis method in this dissertation and provided solutions to the different problems presented in each of the five papers. In Paper I, a time-to-event model was used to estimate remaining road pavement lifetimes in Sweden. In Paper II, an extension of the model in Paper I assessed the impact of latent variables on road lifetimes; displaying the sections in a road network that are weaker due to e.g. subsoil conditions or undetected heavy traffic. The study in Paper III incorporated a probabilistic parametric distribution as a representation of road lifetimes into an equation for the marginal cost of road wear. Differentiated road wear marginal costs for heavy and light vehicles are an important information basis for decisions regarding vehicle miles traveled (VMT) taxation policies. In Paper IV, a distribution based clustering method was used to distinguish between road segments that are deteriorating and road segments that have a stationary road condition. Within railway networks, temporary speed restrictions are often imposed because of maintenance and must be addressed in order to keep punctuality. The study in Paper V evaluated the empirical effect on running time of speed restrictions on a Norwegian railway line using a generalized linear mixed model.

Sleeping gazelles : High profits but no growth

Among 104,231 limited liability firms in Sweden with at least two employees during 1997- 2010, almost 10% did not hire new employees in any given 3-year period despite having high profits. Nearly half of these firms continued to have high or medium profits in the next threeyear period, but still no growth. Regression analysis indicates that these firms were not randomly distributed; rather they were small and young, did not belong to an enterprise group, and operated in local markets with high profit-opportunities. We conclude that it might be more beneficial to focus policy towards these firms instead of towards a few high-growth firms that, having just grown exponentially, may not be best positioned to grow further.

Young adults’ perceptions of and affective bonds to a rural tourism community

Many rural areas, in Sweden and worldwide, experience population decline where the young leave for education and work in urban areas. Employment has declined in several rural industries, such as agriculture, forestry, and fishing, while growing in other industries are often located in urban areas. Politicians and organizations have put much hope in tourism as a tool of rural development, but can tourism help reverse the rural out-migration trend among young adults? This paper explores how tourism affects young inhabitants’ perceptions of and affective bonds to a rural area in Sweden, the ski resort of Sälen. Students from the 1993–1995 elementary school graduating classes were interviewed about their migration history, childhood, and view of and ties to Sälen. The respondents experience that tourism contributes to a more vital community incorporating influences from elsewhere, but without eliminating the positive aspects of rural life. The regular flow of people – tourists, seasonal workers, and entrepreneurs – passing through Sälen presents opportunities to extend one’s social network that are widely appreciated by respondents. The high in and out mobility constitutes a key part of Sälen’s character. Contributions from tourism – such as employment, entertainment, leisure, and opportunities to forge new social relationships – are available during the adult transition, the life phase when rural areas are often perceived as least attractive. Even though out-migration occurs in Sälen, and some respondents still find Sälen too small, tourism has clearly increased the available opportunities and contributed significantly to making Sälen more attractive to young adults.

Reindeer habitat selection under the risk of brown bear predation during calving season

The depredation of semi-domesticated reindeer by large carnivores reflects an important human-wildlife conflict in Fennoscandia. Recent studies have revealed that brown bears (Ursus arctos) may kill substantial numbers of reindeer calves (Rangifer tarandus tarandus) in forest areas in Sweden. Several authors have suggested that predation risk is an important driver of habitat selection in wild Rangifer populations where predation is a limiting factor, but little is known about these mechanisms in semi-domesticated populations. We examined the habitat selection of female reindeer in relation to spatial and temporal variations in brown bear predation risk on the reindeer calving grounds and evaluated the simultaneous responses of brown bears and reindeer to landscape characteristics. We used GPS data from 110 reindeer years (97 individuals) and 29 brown bear years (19 individuals), from two reindeer herding districts in the forest area of northern Sweden. Our results did not indicate that reindeer alter their behavior in response to spatiotemporal variation in brown bear predation risk, on the scale of the calving range. Instead, we suggest that spatiotemporal behavioral adjustments by brown bears were the main driver of prey-predator interactions in our study system. Contrasting responses by brown bears and reindeer to clear-cuts and young forest indicate that forestry can influence species interactions and possibly yield negative consequences for the reindeer herd. Even if clear-cuts may be beneficial in terms of calf survival, logging activity will eventually cause greater abundance of young regenerating forest, reducing available reindeer habitats and increasing habitat preferred by brown bears. Domestication may have made semi-domesticated reindeer in Fennoscandia less adapted to cope with predators. Areal restrictions, limiting the opportunity for dispersion and escape, possibly make the calves more susceptible to predation. Also, a generally higher population density in semi-domesticated herds compared to wild populations can make dispersion a less efficient strategy and the reindeer calves easier prey. Overall, the lack of ability of the reindeer females to reduce brown bear encounter risk on the scale of the calving range is probably an important reason for the high brown bear predation rates on reindeer calves documented in our study areas. 

Sustainability & Consumer behavior towards Sustainability in Norway and Sweden

AimSustainability has become an important factor to consider while buying goods and services. People are being more conscious toward environmental impacts of products and services. This attitude has motivated many businesses to develop their production in contact with sustainability. The aim of this paper is to investigate different consumer behaviors toward sustainability in general and in relation to vehicles in Norway and Sweden.ApproachThe project has been embarked by dividing it into two tasks.1. Analyzing past, present and future development, growth and importance of sustainability concept. Describe the role of Government authorities in Norway and Sweden to promote sustainable consumption.2. Investigating important factors of consumer behaviors which influence their buying decision toward sustainable products in general and in relation to sustainable vehicles. Highlight the role of vehicle manufacturing companies to promote sustainable consumption.MethodA research has been conducted in order to explore consumer behavior toward sustainability in Norway and Sweden. Research is based on Document study and primary research which include questionnaire survey with consumers and interviews with vehicle dealers. In addition an expert inquiry is conducted to light up consumer intensions in Norway and Sweden toward sustainability.ResultsThe result of investigation has been revealed in shape of analyses and conclusion at the end. A comparison has been made between primary research and secondary research and findings are overlapping. Sustainable vehicles are being more popular among consumers in Norway and Sweden. Consumption trends are changing over time and environmental friendly attitudes are more developing among Swedish consumers as compared to Norwegian.

Perceptions of climate change at ski resorts in midsouth of Sweden

Climate change as a phenomenon will imply new risks for the ski industry. Intergovernmental Panal on Climate Change presents three future scenarios, during the periods between 1990-2100, in forms of increased temperatures, a rise in the sea level and seasonal variations, variables out of which two have direct impacts on the ski industry. The aim for this study was to explore and compare attitudes towards climate change between five ski resorts located in mid-south of Sweden. This was done through in depth interviews in both face to face and by telephone. The result of the study was that all the chosen ski resorts were aware of climate change as a phenomenon but have not yet recognized its consequences. All ski resorts use methods to maintain skiing i.e. artificial snow production though not because of climate change.

Obstacles and Opportunities Foreign Graduates Meet In Dalarna Labour Market, Sweden

Foreign graduates have been part of the success stories of many developed countries. This is as a result of their immeasurable deposit of ideas, knowledge, and innovation in the host country. Though the process of these foreign graduates penetrating and integrating into the labour market of the host country could be slow and rough as they encounter some obstacles on the way; they still strive to break through and be part of the country’s workforce because they foresee some opportunities therein. This research study is about the obstacles and opportunities foreign graduates meet in Dalarna labour market. The study investigated and identified the obstacles and opportunities foreign graduates meet in Dalarna labour market. For a thorough execution of this research, we collected primary data by handing questionnaires to 65 foreign graduates searching for jobs in Dalarna region and interviewed eight people, among which seven were foreign graduates and one of them was a staff at Arbestförmedlingen (Employment Agency) to give us a general view of the Dalarna labour market. We read previous research works and related articles to understand the topic in order to get an overview of the terminologies and concept to apply. This study concluded that language is a major obstacle foreign graduates meet in the Dalarna labour market. Other possible obstacles include culture, poor integration policies, lack of a placement bureau, lack of trust, limited opportunities, favoritism, lack of jobs, lack of references and experience. On the other hand factors like job availability, outgoing labour force and unskilled labour are possible opportunities foreign graduates meet in the Dalarna labour market. Furthermore flexible work time, good working atmosphere, experience, social security/welfare, good standard of living, family friendly region, higher wages, job security and cheap cost of living are also possible benefits that foreign graduates get in Dalarna.

Sustainability and research integrated in engineering courses at Dalarna University, Sweden

Högskolepedagogik, högskolepedagogisk utbildning, BHU

Corporal Punishment : A study about attitudes and opinions to corporal punishment and the connection to children’s rights in South Africa and Sweden

Corporal punishment is a worldwide problem. The purpose withthis thesis is to promote a constructive discussion about the problem andconnect this to children’s rights. This gives the possibility to start adiscussion about suggestions and measures to reduce the problem. Thetheory is that corporal punishment is used as a disciplinary method tochange behavior. Children’s rights is regulated by conventions and nationallaws. The method is to conduct an analysis with interpretations andcommentaries of the research materials from South Africa and Sweden.The conclusion is that those who are positive to corporal punishment thinksit is an efficient working method, and it is about children’s safety. Thosewho are negative have experienced that alternative methods works. Asuggestion is to involve children in the work with children’s rights andeducate them in human and children’s rights with focus on obligations andresponsibility.

On processing GPS tracking data of car-movements in Borlänge, Sweden

The advancement of GPS technology enables GPS devices not only to be used as orientation and navigation tools, but also to track travelled routes. GPS tracking data provides essential information for a broad range of urban planning applications such as transportation routing and planning, traffic management and environmental control. This paper describes on processing the data that was collected by tracking the cars of 316 volunteers over a seven-week period. The detailed information is extracted. The processed data is further connected to the underlying road network by means of maps. Geographical maps are applied to check how the car-movements match the road network. The maps capture the complexity of the car-movements in the urban area. The results show that 90% of the trips on the plane match the road network within a tolerance.

Teacher’s leadership in web-based language courses in Dalarna University, Sweden

The purpose of this presentation is to discuss how teacher’s leadership can be used as a teaching method in web based language education. The environments that offer online courses provide a wide field for discussion on the contact between teacher and student. My intention is to contribute to the debate on teacher leadership in online courses. In my earlier studies on leadership, I have explored how some religious leaders affected different social movements in Brazil during the military dictatorship (1964-1985). Pruth (2004) by examining the three kinds of legitimacy described by Max Weber I aimed at seeing and analyzing how religious leaders used different teaching methods to explain their messages to ordinary citizens. Thus my research showed how educational leadership is a way to get people to reach their goals. I became interested in the subject teacher’s leadership whenI participated in a survey of the teaching methods of language courses in Dalarna University which is funded by the NGL Center of Dalarna University. In  this project, we have made interviews with the teachers, undertaken the course plans (in the language department at Dalarna University) and categorized the learning outcomes. A questionnaire was constructed based on the learning outcomes and then either sent out remotely to teachers or completed face to face through interviews. The answers provided to the questionnaires enabled the  project to identify many differences in how language teachers interact with their students but  also, the way of giving feedback, motivating and helping students, types of class activities and materials used. This made me aware of how teachers use their leadership or not in their teaching. My focus is to look at the relationship between teachers and students as an important part of the development and quality of online courses. The teacher's performance on campus is different from online courses. I want to understand how the contact between teachers and students in online courses develop and look at how students can make use of this contact and what influence the teacher's leadership has on the ability for the students to achieve the goals of their course

Geoprocessing journey-to-work data : delineating commuting regions in Dalarna, Sweden

Delineation of commuting regions has always been based on statistical units, often municipalities or wards. However, using these units has certain disadvantages as their land areas differ considerably. Much information is lost in the larger spatial base units and distortions in self-containment values, the main criterion in rule-based delineation procedures, occur. Alternatively, one can start from relatively small standard size units such as hexagons. In this way, much greater detail in spatial patterns is obtained. In this paper, regions are built by means of intrazonal maximization (Intramax) on the basis of hexagons. The use of geoprocessing tools, specifically developed for the processing ofcommuting data, speeds up processing time considerably. The results of the Intramax analysis are evaluated with travel-to-work area constraints, and comparisons are made with commuting fields, accessibility to employment, commuting flow density and network commuting flow size. From selected steps in the regionalization process, a hierarchy of nested commuting regions emerges, revealing the complexity of commuting patterns.

Modeling Hospital Readmissions in Dalarna County, Sweden

Unplanned hospital readmissions increase health and medical care costs and indicate lower the lower quality of the healthcare services. Hence, predicting patients at risk to be readmitted is of interest. Using administrative data of patients being treated in the medical centers and hospitals in the Dalarna County, Sweden, during 2008 – 2016 two risk prediction models of hospital readmission are built. The first model relies on the logistic regression (LR) approach, predicts correctly 2,648 out of 3,392 observed readmission in the test dataset, reaching a c-statistics of 0.69. The second model is built using random forests (RF) algorithm; correctly predicts 2,183 readmission (out of 3,366) and 13,198 non-readmission events (out of 18,982). The discriminating ability of the best performing RF model (c-statistic 0.60) is comparable to that of the logistic model. Although the discriminating ability of both LR and RF risk prediction models is relatively modest, still these models are capable to identify patients running high risk of hospital readmission. These patients can then be targeted with specific interventions, in order to prevent the readmission, improve patients’ quality of life and reduce health and medical care costs.