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  • 201.
    Jaldell, Henrik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Measuring Productive Performance Using Binary And Ordinal Output Variables: The Case of the Swedish Fire and Rescue Services2019In: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 57, no 3, p. 907-917Article in journal (Refereed)
    Abstract [en]

    Fire protection is an example of a complex production process. This study measures efficiency by constructing binary and ordinal output variables from information on residential fires in Sweden about how a fire spreads from when the fire and rescue brigade arrives to when a fire is suppressed. The motivations behind this study are that there are only a few studies trying to estimate production efficiency for fire and rescue services, that data on a more detailed level is interesting for some public services, and there is a need to be able to measure efficiency differences even if only a binary or ordinal output variable is available. Using a logit random parameter model, the random effects are interpreted as efficiency differences. The conclusions are that fire and rescue services with a more flexible fire organisation with first response persons, working in collaboration with other municipalities and with larger populations are more efficient.

  • 202. Jansson, C.
    et al.
    Berghel, Jonas
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Interdisciplinary Basic Course in Engineering Teamwork2002Conference paper (Refereed)
  • 203.
    Jernberg, John
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Indexbaserad kartering av markfuktighet2018Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The increasing need for reliable identification of wet soils in nature preservation and forestry requires more detailed and accurate maps.  Previous maps are mostly based on aerial photos which may result in an incomplete and generalized representation of wetlands. Using high resolution LiDAR-data and modern GIS software, topographic indices can be generated which has the potential to model wetlands in a more realistic and detailed manner.

    This study evaluated the widely used Topgraphic Wetness Index (TWI) and the more recently developed Depth to Water Index (DTW). Five TWI-raster with a resolution of 2-20 m was created. Four DTW-raster with 2 m resolution was created with Flow Initiation Threshold varying between 1-8 ha. A vegetation map (GSD-Vegetationsdata) was used as reference since it was judged to be the best available option for comparison.

    The results show that the index-maps overall identify more wetland area than the vegetation map. The DTW-index generates a clearer and realistic map compared to the TWI. The methods used for index-based mapping of soil moisture has some uncertainties. However, the DTW-index has good potential for further development. It was concluded that index-based maps (primarily DTW) can be useful for identification of soil moisture, especially if combined with other sources of map data. 

  • 204.
    Johansson, Christoffer
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Energianalys och effektivisering av kommunal byggnad: Dagcenter i Hultsfred, med fokus på ventilation och belysning2012Independent thesis Advanced level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Hoten om klimatförändringar och global uppvärmning blir allt mer påtagliga och kraftiga åtgärder måste till. Genom att låta den offentliga sektorn föregå med gott exempel hoppas världens ledare att resurs- och energieffektiviserande arbete ska bli en självklar del för alla världens företag. På uppdrag av Östra Smålands Kommunalteknikförbund har därför potentialen för energieffektivisering undersökts i ett dagcenter i Hultsfred, Småland, med fokus på ventilation och belysning. Med en metod som bland annat innefattade att studera ritningar och statistik, intervjuer med fastighetsskötare samt flertalet platsbesök, har energianvändningen analyserats. För byggnaden i allmänhet och dessa båda system i synnerhet och förslag på tekniska lösningar för att minska förbrukningen av värme och el har tagits fram. Dessa har sedan utvärderats ekonomiskt, bland annat med hjälp av livscykelkostnadsanalyser. Resultatet visar att det finns möjligheter att spara väldigt mycket energi, som idag bara försvinner till ingen nytta. Ungefär 120 MWh fjärrvärme och 30 000 kWh el skulle kunna sparas, samtidigt som sådana förändringar leder till att lokalerna upplevs trevligare och personalen trivs bättre.

    Om renovering och ombyggnation blir aktuellt borde dock en konsult anlitas och sätta sig in i objektet för att ge mer exakta siffror eftersom beräkningarna inte kan förutsättas stämma exakt med verkligheten. Analysen ska betraktas som en inledande studie för att på detta sätt kunna hjälpa kommunen att minska sina energikostnader och samtidigt göra en insats för en bättre miljö, eftersom den mest miljövänliga kWh är den som aldrig behöver skapas!

  • 205. Johansson, Dennis
    Reduktion av mikroorganismer i diskmaskiner  med vattenånga.2017Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Bacteria are a type of microorganism that causes several kinds of problems in dishwashers, one problem being that the bacteria create strong and difficult smells. Bacteria arise from the fact that food residue on the dirt tray serves as nutrition for the bacteria for a long time. To minimize the bad smell, use a dishwashing program with hot water and usually a dishwasher detergent. This is independent of the amount of dirty disk actually in the dishwasher. It will be both a cost issue and an environmental issue through a waste of natural resources. The optimum is a solution that is directly aimed at removing and reducing existing microorganisms on the counter as well as in the dishwasher that does not use machine dishwashing and minimal water and electricity. This then does not need a more intensive program. The purpose of the study is to show how hot steam can be used to reduce the amount of bacteria on the dirty disk.The method used to test the reliability of the vapor treatment system was to use a solution of yeast cells with sodium chloride which had grown into a 24-hour heat sink in a pressure plate with agar solution used as a yeast cell feed. Then they were brought into a specially configured dishwasher where hot steam was injected into the system to work to reduce the bacteria on the plates.The number of microorganisms was compared before and after the treatment of the vapor. The tests were conducted until there was a clear connection between water use, the time of steam treatment and the reduction of yeast cells. This continued until a 95 percent reduction of microorganisms had been achieved throughout the dishwasher regardless of where the contaminated plates were located.The conclusion is that the steam treatment was more expensive than the existing technology, and the dishwasher needed to be supplemented by a method of heating the water to 100 °C. A simple rinse with hot water gave similar results and was cheaper and easier as the machines were already equipped with such a functionThere is a market for the steam method, as the method is especially interesting for individuals with additional disinfection needs, for example for people with poor immune system.

  • 206.
    Johansson, Emma
    et al.
    Karlstad University.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Wastewater treatment plants as energy producers: Comparison of status quo in Sweden and India2018In: Vatten, ISSN 0042-2886, Vol. 73, no 151, article id 160Article in journal (Other academic)
    Abstract [en]

    As the population of the world rises and economies grow, both energy and water will be needed in ever-increasing quantities. There is a delicate balance between these two resources called the energy-water (or the water-energy) nexus. One way to reduce the energy consumption associated with wastewater treatment is to use the sludge produced during the process to generate biogas. In most countries in the developed world, the coverage, standards and reliability of wastewater treatment are high.  But as the countries in the developing world are striving towards the living standards of those in the developed world, even as they combat population pressure, it is  imperative that they  learn from the experiences (the mistakes which occurred during the ‘learning-by-doing’ process) of the developed world. In this paper, Sweden has been used as a proxy for the developed world with a well-functioning sanitation infrastructure and reliable power supply; and India (the home country of one of the coauthors) is a proxy for the developing world which lacks the same. A very important starting point for development would be to educate people about the long-term socio-economic and environmental benefits of wastewater treatment

     

  • 207.
    Johansson, Josefina
    Karlstad University.
    Energieffektivisering av ventilationssystem i en skola: Behovsstyrd ventilation i fastigheten Eken i Karlstad kommun2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    I Sverige står bostads-och servicesektorn för nästan 40 % av den totala energianvändningen och därför har många byggnader behov av energieffektivisering. Arbetet utgår från Eken, en del av Karlbergsskolan i centrala Karlstad, som är en kulturmärkt byggnad från 1890-talet. I byggnaden pågår gymnasieutbildning, förskola samt idrottsverksamhet i en gymnastiksal. Byggnaden ventileras i dagsläget med konstant luftflödessystem (CAV).

    Behovsstyrd ventilation (DCV) innebär att reglera ventilationen efter närvaro och behov, genom att upprätthålla en bra luftkvalité och termisk komfort och samtidigt effektivisera energiförbrukningen. Syftet med detta arbete var att undersöka hur behovsstyrning med IR-sensorer eller CO2-sensorer kan påverka energiförbrukningen och driftkostnader av Ekens ventilationssystem, samt undersöka hur innetemperaturen påverkas vid CO2-reglering jämfört med befintligt driftfall. Målet var att beräkna årliga energibesparingar (MWh/år) och investeringsutrymme (kr) till utgifter som uppkommer vid ombyggnation av dagens CAV-system. Ett ytterligare mål var att beräkna innetemperatur vid olika fall då förutsättningar som rumsplacering, solinstrålning, utetemperatur och intern personbelastning varieras och beroende på CO2-reglerat eller konstant luftflöde. Energibesparingar avseende energi till fläktar och värmebatterier, beräknades i Excel baserat på olika luftflöden beroende på personbelastning. Investeringsutrymmet beräknades utifrån årliga besparingar av driftkostnader. Innetemperaturer beräknades i en dynamisk simuleringsmodell för tre dygn och tre rum med olika förutsättningar.

    Energibesparingar för IR- och CO2-reglering av ventilationssystemet resulterade i 53 MWh/år (-44 %) respektive 77 MWh/år (-64 %) jämfört med befintligt CAV-system. Efter 15 år bidrog IR- och CO2-reglering till besparingar på ca 520 kkr (IR) respektive 750 kkr (CO2). Skillnaden på innetemperaturen vid behovsstyrt flöde jämfört med konstant luftflöde var lägre än en grad i majoriteten av fallen. Den största skillnaden på 2,7 °C uppstod en solig dag för ett rum med fönster mot sydost.

    Behovsstyrning är uppenbart fördelaktigt för byggnaden ur energi- och miljöperspektiv. Investeringskostnaden för de två olika metoderna är troligtvis ungefär lika stora och hur ekonomiskt lönsam investeringen är beror på återbetalningstiden. Luftflödesreglering leder inte till några större problem för rumstemperaturen och i annat fall borde temperaturproblem kunna åtgärdas genom solavskärmning eller temporärt ökat ventilationsflöde.

  • 208.
    Johansson, Robin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Fält- och prestandatester av ett vattenvärmedrivet torkskåp: Granskning av fälttester, driftbetingelser samt styrparametrar för vattenvärmedrivet torkskåp2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 209.
    Johansson, Staffan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Energianvändning i mejeriverksamhet: En fallstudie vid Wermlands Mejeri AB med fokus på elanvändning och kylbehov2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The dairy industry is one of the world’s largest industries, and the most rapidly expanding sector of agriculture. Every year more than 800 million tons of milk is produced globally, of which the Swedish population annually consumes more than 150 kg per capita. Refinement of milk includes several processes that require large amounts of energy, mainly in the form of steam for heating of milk and electricity for cooling. Milk is an extraordinary environment for bacteria and spores to thrive in. The main reasons the milk has to go through these heating and cooling process is to reduce the bacterial count, rendering the product safe to drink and of a consistent quality. To meet the environmental challenges that lie ahead, it is important that sustainable solutions for the dairy industry are developed and implemented. According to the environmental code, all industries shall use renewable energy sources to the highest possible degree, recycling of heat shall be used and housekeeping of energy and other resources is of uttermost importance.

    Wermlands Mejeri, a dairy plant in Värmlands Nysäter, started their operations in September 2015. Today they produce around 18 400 liters of dairy product, with a product portfolio consisting of three different types of milk (0.5, 1.8, and 3 percent fat) and cream. Their goal is to expand the operation, so that the production volume will be doubled by august 2016.

    The commencing chapter of this report is based on a survey with the goal of defining the total energy consumption at the plant, and also to investigate how the use of energy is allocated between the different processes. This survey is purposed to be compared to the energy consumption at other similar dairy plants, in order to point out if (and where) there is any potential to increase the energy efficiency. When comparing different facilities, the key indicator Specific Energy Consumption (SEC) is used. SEC is defined as the total used energy divided by the amount of product, and can be applied on specific processes as well as an entire operation. The investigation consists of physical measuring, thermodynamical calculations and simulations in SimuLink.

    According to this survey, Wermlands Mejeri annually consumes 1 141 MWh of energy, equalling a SEC-value of 0.19 kWh/liter produced milk. When the production is expanded, the energy consumption is predicted to total 1 570 MWh per year, or 0.13 kWh/liter. As a point of reference, the SEC-values of two dairy plants used in the comparison are 0.11 and 0.12 kWh/liter respectively.

    In the second section of this report, five different operational improvements are defined and investigated, with the purpose of reducing the consumption of electric energy at the plant, and to reduce the operational cost. This investigation is focused on the cooling system and the ventilation equipment. The solutions consist of re-use of heat during cream cooling, usage of the ground as a heat sink for the liquid coolers, refrigerating the cold storage with outside air, extra insulation of the cold storage ceiling, and time-regulation of the ventilation system. At least three of the proposed improvements should be considered for implementation, as they indicate cost-effective ways to reduce the energy consumption.

  • 210. Johansson, Tore
    Nutidsbeskrivning av PFAS i dagvatten för området Frösö Park: Med fokus mot reningsmetoder och hur PFAS-situationen ser ut för framtiden2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    PFAS is a relatively new group of contaminants with unique characteristics, which in the early 21

    st century was understood being dangerous for both humans and the environment. In 2008, EFSA published a report on guidelines for human intake of PFAS. Target and limit values for ground and surface water around the world has been based on the information in the EFSA report. In the end of 2018, EFSA published a new preliminary report with new target values for PFAS, well below the target values published in 2008.

    Frösö Park in Östersund, Sweden, is polluted by PFAS from the time that the Swedish Armed Forces were active in the area. While the Swedish Armed Forces exercised their activities at Frösö Park, large amounts of aqueous fire-fighting foams were used, mainly for training purposes. AFFF at that time contained a mixture of many highly fluorinated chemicals known as PFAS, a collective name of more than 4,700 chemicals consisting of carbon-fluorine bonds. PFAS are, more or less, persistent, bioaccumulative and toxic. This study focuses on PFAS

    11, which Sweden has target and limit values for in respect of ground water and surface water (lake and sea). PFOS is the most common PFAS chemical and the most commonly occurring PFAS chemical at the Frösö Park area.

  • 211.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Att skilja agnarna från vetet ' om hållbar användning av genmodifierade organismer2001In: Sveriges Utsädesförenings Tidskrift 111, 21-27Article in journal (Other (popular science, discussion, etc.))
  • 212.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Biosafety Principles for GMOs in the Context of Sustainable Development2003In: International Journal of Sustainable Development and World Ecology 10, 15-27Article in journal (Refereed)
    Abstract [en]

    If genetically modified organisms are to contribute to welfare they must be considered in the context of sustainable development. Biosafety implies considering the environmental, economic and social dimensions of sustainable development. These dimensions can be interpreted through the principles of precaution, polluter pays and public participation. In this article, these key biosafety principles are operationalised and ways of implementing them in society is discussed. A comparison is made between the principles and the present EU law for deliberate release of GMOs. It is concluded that several improvements in the EU policy are necessary to ensure sustainable development really is promoted

  • 213.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Ethics of Sustainable Development ' a Study of Swedish Regulations for Genetically Modified Organisms2003In: Journal of Agricultural and Environmental Ethics 16, 51-62Article in journal (Refereed)
    Abstract [en]

    In spite of stricter provisions in the new EU directive on deliberate release of genetically modified organisms (GMOs), critics still advocate a moratorium on permits for cultivation of GMOs. However, in an attempt to meet concerns raised by the public, the directive explicitly gives Member States the possibility to take into consideration ethical aspects of GMOs in the decision-making. This article investigates the potential effects of such formulation by means of an empirical analysis of experiences gained the last years from similar Swedish regulations for GMOs, aiming at promoting sustainable development. The faulty implementation shown in the Swedish case indicates that legal stipulations for ethics as such have limited importance. It is suggested that public participation is an important factor for successful implementation of the ethics of sustainable development

  • 214.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Genetically Modified Trees in the Context of Sustainable Development2003Conference paper (Refereed)
  • 215.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Genmodifiering av skogsträd i perspektivet hållbar utveckling2004Chapter in book (Other academic)
  • 216.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Konflikthantering för hållbar utveckling ' om människor och skyddade skogar i Tanzania2004Chapter in book (Other academic)
  • 217.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Managing Complex Environmental Risks for Sustainable Development2005Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The thesis is concerned with the problematic question on how to manage complex environmental risks in a way that promotes sustainable development. While there are some positive signs on progressive and successful environmental policy, environmental change resulting from human activities still causes severe problems and risks worldwide.



    Environmental risks are conventionally handled through a process in which experts try to quantitatively assess, evaluate and manage risks. This approach harmonises with mainstream interpretations of sustainable development, aiming at describing and prescribing a certain relationship between human and natural systems, for instance by policies that define limit values for pollutants.



    Often, however, scientific incertitude (risk, ambiguity, uncertainty, ignorance) and diverging social values and norms as well as distrust, challenge such policies. The thesis describes this dilemma by an investigation of public risk policies in Sweden and the European Union for hazardous chemicals and genetically modified organisms.



    Against this background, and in the light of new ideas on the notion of risk from social sciences, a new, complementary interpretation of the concept of sustainable development is suggested. This, in turn, is operationalised by help of new formulations of three principles for improving public risk management; the precautionary principle, the polluter pays principle and the principle of public participation.



    Implementation of these principles would challenge present mainstream views on environmental decision-making. Thereby the thesis aims to contribute to the growing number of voices that ask for sustainable development in not only rhetoric, but also practices for long-term human welfare and planetary survival

  • 218.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Miljörätt och miljöpolitik2001In: Miljö i ett företagsperspektiv, Stockholm: PREVENT , 2001Chapter in book (Other academic)
  • 219.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Regulatory frameworks for sustainable control of genetically modified organisms2000Conference paper (Refereed)
  • 220.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Risk Management of Genetically Modified Organisms and Hazardous Chemicals for Sustainable Development2004Conference paper (Other (popular science, discussion, etc.))
  • 221.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Science and norms in policies for sustainable development: Assessing and managing risks of chemical substances and genetically modifed organisms in the European Union2006In: Regulatory Toxicology and Pharmacology 44, 49-56Article in journal (Refereed)
    Abstract [en]

    Use of chemical substances and genetically modifed organisms cause complex problems characterised by scientifc uncertainty and controversies. Aiming at sustainable development, policies for assessment, and management of risks in the two areas are under development in the European Union. The article points out that both science and norms play a central role in risk assessment as well as risk management and suggests that the precautionary principle, the principle of public participation, and the polluter pays principle, all adopted in the European Union, offer a way to operationalise the concept of sustainable development. It is shown, however, that a number of steps ought to be taken to better implement the principles through different policy measures. In doing so, and by recognising the role of both science and norms, the decision-making on risks related to the use of chemicals or genetically modifed organisms can be improved to better promote sustainable development

  • 222.
    Karlsson, Mikael
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    The Precautionary Principle, Swedish Chemicals Policy and Sustainable Development2006In: Journal of Risk Research, Vol. 9, No. 4, 337360,Article in journal (Refereed)
    Abstract [en]

    The precautionary principle is one of the most contested principles in the debate on the new EU chemicals legislation. The purpose of this paper is to

    operationalise the principle and to investigate the consequences of its application. Five core elements of precautionary management of chemicals are derived and traced in Swedish policy and legislation through history. It is shown that precautionary measures were required as early as the eighteenth century. The conclusion is drawn that these measures in Sweden seem to have promoted sustainable development from both an environmental and a socio-economic point of view

  • 223.
    Karlsson, Mikael
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Karlsson, Hanna
    Beyond the limits: On Violated Environmental Quality Standards and Health Effects from Particles in Sweden2006Conference paper (Refereed)
    Abstract [en]

    The present levels of particles in the air present a serious health problem in Sweden and legal quality standards for particles are violated. The article analyses if the environmental quality standard is possible to maintain by present legislation, if the standard is based on scientific facts concerning which types of particles that are most hazardous, and if the proposed legally based action programme for counteracting particle concentrations in Stockholm beyond the limits is effective. It suggests developed legislation, a new standard for fine particles and increased focus on traffic reducing measures, if the standards are to be maintained

  • 224.
    Karlsson, Mikael
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Kåberger, Tomas
    Polluter Accountability for Nuclear Energy Systems in a New Risk Context2005Conference paper (Refereed)
    Abstract [en]

    The polluter pays principle is a world-wide principal cornerstone for polluter accountability in environmental policy. It is a prerequisite for avoiding the establishment of too destructive industrial plants. According to EU legislation, the polluter is supposed to pay for both preventive measures and remediation related to adverse effects on human health and the environment.



    That said, much remains to be decided when implementing the principle in practice. This paper investigates the operationalisation of the polluter pays principle in relation to negative effects associated with nuclear power.



    More and less predictable quantities of radioactive pollution will pose uncertain risks to an unknown number of future human beings. How can polluter accountability be assessed and valued? Who should make these decisions and in what ways?



    These questions are discussed in relation to the development of the risk discourse in society since the early days of the nuclear epoch. To conclude, the new risk context leads to a questioning of present policy regimes and brings a set of new regulatory ideas to the fore

  • 225.
    Karlsson, Mikael
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Lindh, Magnus
    Understanding Sustainable Development: A Systemic View for Successful Realisation2001Conference paper (Refereed)
  • 226.
    Karlsson, Mikael
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Swahn, Johan
    Nuclear Waste, Risks and Sustainable Development2006Conference paper (Refereed)
  • 227.
    Karlsson, Simon
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Christiansson, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Calles, Olle
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Granö fiskavledare2015Report (Other academic)
    Abstract [sv]

    Utvinning av vattenkraft från Granö kraftstation påbörjades på slutet av 1950-talet. Ålen har sedan dess varit hindrad att passera genom kraftverket av ett finmaskigt och höglutande nät under ålens vandringssäsonger. Den alternativa vägen runt stationen har varit med spillvatten eller ner i den gamla ålkistan placerad i intagskanalen. Det är okänt hur många ålar som faktiskt vandrat ut med spillvattnet, men fångsterna i den gamla ålkistan har varit begränsade och mängder med ålar har dött på nätet. Ålen är nu akut hotad och åtgärder att mildra kraftverkens negativa inverkan på utvandrande blankål har högsta prioritet.

    Till följd av problem med igensättning av den så kallade ålspärren uppstod ett dammbrott 2010. För att öka dammsäkerheten och effektiviteten för åluppsamling designades och uppfördes en ny fiskavledare med åluppsamlingsanläggning 2011. Granö fiskavledare är unik i sitt slag då den har intagsgaller av kompositmaterial, ställbara lutningar (30-40˚), samt flyktöppningar som leder till en uppsamlingsbur. Vattnet från uppsamlingen pumpas tillbaka till intagskanalen, för att undvika onödigt spill.

    En stor del av utvärderingen bestod i märkning och spårning av blankål i anslutning till avledaren. Märkningsförsöken under 2012 och 2013 visade att endast en liten proportion av fisken hittar flyktöppningarna och kommer till uppsamlingsburen, dessutom har skador på fisken kunna relateras till avledaren och uppsamlingsburen. Totalt har 284 ålar märkts och 475 har visuellt bedömts för skador efter passage genom avledaren eller referensfisket Havbältan. Trots två dåliga ålvandringsår har majoriteten av den radiomärkta fisken ankommit till avledaren och totalt har 15 fisk återfångades. Hydrauliska mätningar i flyktöppningarna visar att vattenflödena igenom avledarsystemet är låga och andelen (vatten genom avledaren/totalflöde) är långt under rekommenderat vilket kan vara en anledning till de få återfångsterna av fisk.

  • 228.
    Karlsson, Victor
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Pyrolysintegration i kraftvärmeverk: Utnyttjande av kondenseringsvärme för fjärrkyleproduktion2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The pursuit of a sustainable society has been one of the most important aspects in the 21st century. The big problem is how to achieve this goal. The use of fossil fuels must be reduced, but which energy source should be used to replace it? Biomass has played a significant role in the reduction of fossil fuels used for heating purposes. With new technology its importance may be even greater.

    Fast pyrolysis is a process where a bio oil, called pyrolysis oil, is produced by the degradation of biomass. This process requires external heat, which makes it suitable to integrate with a combined heat and power plant. The problem of combined heat and power plants are its minimal operational during the summer. A pyrolysis integration would increase the use of the facility. The pyrolysis oil that is extracted can replace fossil fuels used in boilers and turbines. It can also be upgraded to bio-diesel, but currently that process is too costly.

    The pyrolysis integration would get maximum production during the summer months. During the same period the cooling demand is increased. During the summer cooling load is covered largely of refrigerating compressors run on electricity. A sustainable society means that the right kind of energy is utilized. Using the high-quality form of energy electricity for comfort is not sustainable.

    The absorption refrigeration cycle is a chiller similar to a refrigeration compressor, with the major difference that it runs on low-temperature water. The pyrolysis process requires one or more condensers in order to extract pyrolysis oil. When the pyrolysis oil condenses low temperature heat is produced. This condensation heat can be used to drive an absorption chiller, which simplified converts heat to cold, with minimal need for electricity.

    The pyrolysis integration with district cooling production would produce heat, electricity, pyrolysis oil and cooling, all originating from biomass. The result from the study shows potential. A cogeneration plant with a combustion boiler steam output of 80 MW has been studied and three different cases were investigated. The first case maximizes the production of pyrolysis oil and produces 78 000 tonnes of pyrolysis oil / year and district cooling equivalent to 11 GWh. The second case maximizes the district cooling production and produces 37 GWh of district cooling and pyrolysis oil equivalent to 68 000 tonnes / year. The last study provides a more balanced production of 74 000 tons of pyrolysis oil / year and 22 GWh of district cooling.

    Future studies should investigate how the cooling effect varies during the day in an attempt to further improve the efficiency of the plant. The liquefaction behavior of pyrolysis oil derived from biomass originating from Scandinavia should also be investigated further.

  • 229.
    Kaukojärvi, Janne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    The Role of Collaboration in Sustainable Innovation: A Case Study of a European R&D Consortium within the Area of Smart Paper-based Electronics2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    For the past decades, sustainability enhancement has become a necessity for ensuring a brighter future for the coming generations. Promoting technologybased innovation is seen as the main path for reaching the ambitious sustainable development goals. However, the academic literature about innovation highlights the need for an open innovation approach because sustainable innovations require consideration of complex issues throughout the entire product life cycle. Building on previous research on external collaboration and radical sustainability-oriented innovation, this qualitative single case study aims at extending the knowledge by particularly focusing on collaborative capabilities in the early development stages of publicly funded networks.

    The empirical findings were obtained through nine semi-structured interviews, and they were supported by available documentation, from the selected European research and development consortium within smart paper-based electronics. The outcome of the thesis is a framework summarizing success factors and challenges for the identified themes; capability, expectation, disposition, communication, management, commitment, and experience. Furthermore, the findings suggest that decision-making, preconditions, resourcing, and commitment, are the four main differences when comparing to collaborative capabilities in small and medium-sized enterprises, and large companies. Concerning managerial implications, top-level managers should carefully consider the strategic objectives of participating in networks, to guarantee organizational and personal commitment.

  • 230.
    Keck, Rolf-Erik
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Strömningsmodell över Laxede kraftsstation2007Independent thesis Basic level (professional degree), 20 points / 30 hpStudent thesis
  • 231. Khan, Z.
    et al.
    Yusup, S.
    Kamble, P.
    Naqvi, Muhammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Watson, I.
    Assessment of energy flows and energy efficiencies in integrated catalytic adsorption steam gasification for hydrogen production2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 225, p. 346-355Article in journal (Refereed)
    Abstract [en]

    This study addresses the energy flows and energy efficiency of integrated catalytic adsorption biomass steam gasification for hydrogen production in a pilot scale bubbling fluidized bed system utilizing palm kernel shell as feedstock. The integrated catalytic adsorption utilizes catalyst and CO2 adsorbent together in the single fluidized bed gasifier. Various variables such as effect of temperature (600–750 °C), steam to biomass ratio (1.5–2.5 w/w), adsorbent to biomass ratio (0.5–1.5 w/w), fluidization velocity (0.15–0.26 m/s) and biomass particle size (0.355–0.500 to 1.0–2.0 mm) are investigated. The results imply that the overall requirement of gasification energy increases with increasing gasification temperature, steam to biomass ratio, fluidization velocity, and decreases with adsorbent to biomass ratio whilst no significant increase is observed by varying the biomass particle size. However, a slight reduction in required energy is observed from 600 °C to 675 °C which might be due to strong CO2 adsorption, an exothermic reaction, and contributes to the energy requirements of the process. Besides, hydrogen-based energy efficiencies increase with increasing temperature while first increases to a medium value of steam to biomass ratio (2.0), adsorbent to biomass ratio (1.0) and fluidization velocity (0.21 m/s) followed by a slight decrease (or remains unchanged). The integrated catalytic adsorption steam gasification is found to be a high energy consuming process and thus, waste heat integration needs to be implemented for feasible hydrogen production

  • 232.
    Kjeang, Are
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Goda råd är inte dyra!: Om personlig energirådgivning i ett alltmer digitaliserat samhälle2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Improving the efficiency of energy use across all the sectors – industrial, transport and households – is one of the many necessary approaches to be adopted to ensure sustainable development. The countries of the developing world have to play a key role in such a transition. In Sweden, for close to half a century now, the municipal energy-advising function has been a governmental instrument to support decision-makers in bringing about systemic changes to improve energy efficiency on the one hand and the share of renewable energy in the mix, on the other.  This licentiate thesis has its focus on this function over the said time-period. It has also documented and analysed the energy-advising function from a social perspective. The research shows that in an increasingly-digitalised society, energy-advising must be developed further to be able to reach and impact different categories of energy users – households, small and medium scale enterprises and organisations – more effectively. The Internet happens to be the first resort of most people seeking information on energy-related issues, these days. Digital services do offer a range of possibilities but cannot substitute for the much-needed personal contact, which is provided by the energy-advising function. In this thesis, focus groups, interviews and conversations with energy advisers, homeowners and experts have been availed of, and subsequently analysed. The results also show that personal energy advice is actually popular, indispensable and effective, where replacement of interior heating systems, refurbishment or new building constructions are concerned.

    This research also shows that interactions with energy advisers are useful to test and verify the suitability of ideas and solutions obtained from the Internet. Besides, the home in which these solutions may eventually be tried out, is the perfect place for having such conversations. In this context, the social skills of the energy adviser assume paramount importance. It has been noticed that the viewpoints and experiences of women in households have often been ignored.  Further, the focus on finding solutions has sometimes been narrowed down to the technical and economic aspects, while at other times, decisions have been based on environmental or social factors like maintenance of comfort levels. In order to make the energy advising function more effective and avail of what it has to offer for the journey towards greater sustainability, it needs to be given the importance it deserves by the municipalities and there is also a need of stronger interplay among the other governmental instruments.

  • 233.
    Kjeang, Are
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Good advice need not be expensive: On personalised energy advising in an increasingly digitised society2019Report (Refereed)
    Abstract [en]

    ”Now good advice is beyond all price”, as Swedes say in a crisis. In this report, whose headline links to the saying, the development and future of Swedish energy advising function are treated. Research shows that in an increasingly digitized society, energy advice needs to be developed to better reach the target groups - households, small businesses and organizations.Digital services offer many opportunities, but the important personal contact with the energy adviser cannot be fully replaced. With the help of focus groups, interviews and conversations with energy advisors, homeowners and individual experts, it has been found that the personally performed advisory service is in demand, urgent and successful when changing the heating system and when major reconstruction or new construction is relevant. Trying ideas and solutions, preferably in the home environment before a rebuilding, is appreciated advice. In the conversation, where not only technical details and profitability are discussed, everyone in the household can be engaged. The energy advice service can be more successful, but then a greater municipal commitment and a clearer interaction with other government instruments is required. Sustainable advice can all get in Sweden today and the good advice is free! With the help of these, crises may be avoided…

    Are Kjeang is senior lecturer in Environmental and Energy Systems at Karlstad University. He is a specialist in energy efficiency in buildings and has extensive experience from working as an energy adviser in a Swedish municipality. This report is a translated and slightly processed version of his licentiate thesis Goda råd är inte dyra! Om personlig energirådgivning i ett alltmer digitaliserat samhälle (2018).

  • 234.
    Kjeang, Are
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology. Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Palm, Jenny
    2 IIIEEE, International Institute for Industrial Environmental Economics, Lund University, Lund, Sweden..
    Energy consulting services in the information age: literature review2017In: Energy, Sustainability and Society, ISSN 2192-0567, Vol. 7, no 30, p. 1-10Article in journal (Refereed)
  • 235.
    Kjeang, Are
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Palm, Jenny
    Lunds universitet.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Local Energy Advising in Sweden: Historical Development and Lessons for Future Policy-Making2017In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, no 12, p. 1-13, article id 2275Article in journal (Refereed)
    Abstract [en]

    In Sweden, energy-consulting services, here referred to as local energy advising (LEA), have traditionally contributed to improving household energy efficiency. The aim of this article is to analyze the development of this service from the 1970s, when the consultancy came into being, to the present day, through a review of documents and published literature. The analysis enables the understanding of the evolution of local energy advising as a policy instrument, and provides valuable insights for the future. Local energy advising has often been subsidized by the Swedish government and used as a state policy measure rather than a municipal one. As a policy measure, the function of the service has changed over time. In the early period, the oil crisis was a fact and the local advisers were used to inform households. In the 1980s, however, the task of energy-advising was taken over by the energy companies in the spirit of market liberalization. In the 1990s, Sweden became a member of the European Union, and the emphasis was put on general information campaigns. Recently, the development of decentralized energy systems (including micro-energy systems) has necessitated targeting individuals with information. One important lesson to learn from the historical development of LEA is the imperativeness of providing energy advising at the local rather than the state level for better efficiency.

  • 236.
    Krehel, O.
    et al.
    Eindhoven Univ Technol, Dept Math & Comp Sci, MB Eindhoven.
    Muntean, Adrian
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Knabner, P.
    Univ Erlangen Nurnberg, Dept Math, Erlangen, Germany.
    Multiscale modeling of colloidal dynamics in porous media including aggregation and deposition2015In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 86, p. 209-216Article in journal (Refereed)
  • 237.
    Kuehn, Bernhard
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Off-grid hus: En simuleringsmodell för hus utan koppling mot elnätet2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The European Union has through the Energy Performance of Buildings Directive (EPBD) given a mandate to its members to reduce energy consumption of buildings. This is part of the effort to reduce the carbon footprint across Europe. New houses have the best conditions to reduce their energy consumption by utilizing the latest technologies.

    This work examines whether it is possible to build a house that is self-sufficient in electricity in Sweden using proven technology. The survey is done by building a computer aided model of a house in Simulink to calculate energy requirements during January 2010 and December 2013. The modelhouse is 160 m2 and use climate data from Karlstad, Värmland.

    The calculations show that a self-sufficiency rate of 100 % of electricity is possible with the selected technical equipment by limiting the power consumption to 2 000 kWh per year. Heat supply is done by using solar collectors and a storage tank. Self-sufficiency for the heating is up to 58 %, wooden heating supplies the rest.

  • 238. Kåberger, Tomas
    et al.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Entropy and economic processes ' physics perspectives2001In: Ecological Economics, Vol 36, sid 165-179Article in journal (Refereed)
    Abstract [en]

    This paper is a contribution to the discussion on the relation between thermodynamics and economic theory. With respect to thermodynamic constraints on the economy, there are two diametrically opposite positions in this discussion. One claims that the constraints are insignificant (of no immediate practical importance for modelling) and in the intermediate run, do not limit economic activity and, therefore, need not be incorporated in the economic theory. The other holds that thermodynamics tells us that there are practical limits to materials recycling, which already puts bounds on the economy and, therefore, must be included in the economic models. Using the

    thermodynamic concept of entropy, we show here that there are fundamental problems with both positions. Even in the long run, entropy production associated with material dissipation need not be a limiting factor for economic development. Abundant energy resources from solar radiation may be used to recover dissipated elements. With simple, quantitative analysis we show that the rate of entropy production caused by human economic activities is very small compared to the continuous natural entropy production in the atmosphere and on the Earths surface. Further, the societal entropy production is well within the range of natural variation. It is possible to replace part of the natural entropy production with societal entropy production by making use of solar energy. Society consumes resources otherwise available for coming generations. However, future generations need not have less resources available to them than the present generation. Human industrial activities could be transformed into a sustainable system where the more abundant elements are industrially used and recycled, using solar energy as the driving resource. An economic theory, fit to guide industrial society in that development, must not disregard thermodynamics

    nor must it overstate the consequences of the laws of thermodynamics

  • 239. Landén, Angela
    et al.
    Holby, Ola
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Hall, Per
    Determination of biogenic silica in marine sediments - Selection of pretreatment method and effect of sample size1996In: Vatten 52:85-92Article in journal (Refereed)
  • 240.
    Larsson, Ida
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). RISE Research Institutes of Sweden.
    Measurement of Self-Heating of Biomass Pellets using Isothermal Calorimetry2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Self-heating in storage facilities of biomass pellet can lead to spontaneous combustion. This has resulted in many fires over the years, causing both financial and environmental losses.

    In order to assess the risk for spontaneous combustion of biomass pellets during storage, it is important to know how prone the fuel is to self-heating, i.e. to determine its reactivity. This thesis presents experimental work performed to develop a sensitive screening test procedure for biomass pellets, using isothermal calorimetry for direct measurement of the heat production rate. This method can be used to compare the reactivity of different biomass pellets. This could be useful for e.g. facility owners to gain better knowledge of their fuels propensity for self-heating and thereby facilitate safer storage.

    The screening test procedure can also be used for research purposes. Experiments have been performed with 31 different biomass pellet batches to investigate how the pellet composition, origin, etc. influence the reactivity of the pellets. The results from these experiments clearly show a significant difference in reactivity between different types of pellets. The results indicate that pine/spruce mix pellets are significantly more reactive than all other types of pellets tested, and that pellets consisting of 100 % pine are more reactive than pellets consisting of 100 % spruce. Pellets produced from winery wastes, straw, or eucalyptus, have low reactivity compared to pellets consisting of pine and/or spruce. The reactivity of the pellets was shown to be reduced by either introducing certain types of anti-oxidants into the pellets or by extracting lipids from the raw material of pellets.

    The screening test procedure is already being used today by some facility owners for assessing their fuels propensity for self-heating. The procedure is also one of the suggested test methods in “ISO/CD 20049 Solid biofuels — Determination of self-heating of pelletized biofuels”.

  • 241.
    Larsson, Ida
    et al.
    SP Technical Research Institute of Sweden, Borås, Sweden.
    Lönnermark, Anders
    SP Technical Research Institute of Sweden, Borås, Sweden.
    Blomqvist, Per
    SP Technical Research Institute of Sweden, Borås, Sweden.
    Persson, Henry
    SP Technical Research Institute of Sweden, Borås, Sweden.
    Measurement of self‐heating potential of biomass pellets with isothermal calorimetry2017In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, p. 1-9Article in journal (Refereed)
    Abstract [en]

    In order to assess the risk for spontaneous combustion of biomass pellets during storage it is important to know how prone the fuel is to self-heating, i.e. to determine the reactivity.  This article presents the results from isothermal calorimetry tests performed on 31 different biomass pellet batches. The purpose of the tests has been to characterize pellets by measuring the reactivity and investigate how the pellet composition influences the heat release rate and thereby the self-heating potential of pellets.  The results from the tests clearly indicate that there is a significant difference in reactivity between different types of pellets. The tested high reactive pellet batches reached maximum specific heat release rates (HRRmax) of 0.61-1.06 mW/g while pellet batches with low reactivity showed HRRmax of 0.05-0.18 mW/g. The tested batches were primarily ranked based on HRRmax but an alternative ranking based on specific total heat release rate during the test period was also used for comparison.  The test results also indicate that pine/spruce mix pellets are significantly more reactive than all other types of pellets tested and that pellets consisting of 100 % pine are more reactive than pellets consisting of 100 % spruce. Pellets produced from wine pruning/grape pomace (winery wastes), straw or eucalyptus are not very reactive compared to pellets consisting of pine/spruce.  The results also show that the reactivity of the pellets can be reduced by either introducing certain kinds of anti-oxidants into the pellets or by extracting lipids from the raw material of pellets.

  • 242.
    Larsson, Ida
    et al.
    Fire Research, SP Technical Research Institute of Sweden, Borås, Sweden.
    Lönnermark, Anders
    Fire Research, SP Technical Research Institute of Sweden, Borås, Sweden.
    Blomqvist, Per
    Fire Research, SP Technical Research Institute of Sweden, Borås, Sweden.
    Persson, Henry
    Fire Research, SP Technical Research Institute of Sweden, Borås, Sweden.
    Bohlén, Haleh
    Fire Research, SP Technical Research Institute of Sweden, Borås, Sweden.
    Development of a screening test based on isothermal calorimetry for determination of self-heating potential of biomass pellets2017In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, p. 1-13Article in journal (Refereed)
    Abstract [en]

    For the risk for spontaneous combustion in storage of biomass pellets to be assessed, it is important to know how prone the fuel is to self-heating. There are traditional methods that are used to determine self-heating characteristics of fuels, eg, basket heating tests. The results from basket heating tests indirectly give the reactivity from a series of tests at high temperatures. This paper presents a sensitive screening test procedure for biomass pellets using isothermal calorimetry for direct measurement of the heat production rate at typical bulk storage temperatures. This method can be used to directly compare the reactivity of different batches of biomass pellets. The results could be used, eg, by storage security managers to gain better knowledge of their fuels propensity for self-heating and thereby for safer storage. A large number of tests have been performed to develop the test procedure presented. Different parameters, such as temperature, type of the test sample (powder/crushed or pellets), mass of test sample, and preheating time, have been varied. Furthermore, gas concentrations in the sample ampoule have been measured before and after some tests to study the oxygen consumption and the formation of CO and CO2. Three different types of pellets with different characteristics were tested to assess the variation in behaviour. Based on these tests, a screening test procedure is presented with a test temperature of 60°C, a sample size of 4 g, a 15-minute preheating period at the test temperature, and 24-hour test duration.

  • 243.
    Larsson, Jenny
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Diskmaskin med ångtillförsel: Studie om ånga som glansmedel i diskmaskiner2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Despite repeated warnings regarding the global consequences of greenhouse gas emissions, they continue to increase worldwide. The main carbon dioxide emissions derive from combustion of fossil fuels, which in Europe alone is the source of over half the electricity production. To just replace the fossil fuels with green alternatives would take too long, thus, a lot of focus has been directed at electricity savings as well. The electricity usage of the households is an important sector where a lot of research has been conducted and amongst other things, this includes the electricity usage for dishwashers where a number of alternative technologies for lessened electricity usage have been developed. Dishwashers with steam injection in the pre-wash stage is one of those technologies that is available on the market today. Some dishwasher manufacturers claim that the attributes of steam makes it suitable as a rinse aid in dishwashers.

    The purpose of this study is to investigate whether or not there is any truth to the manufacturers claim regarding steam as an alternative to ordinary rinse aid. A nice gloss on dishes is important to consumers since glossy dishes are perceived as “spotlessly clean”. There is also an electricity savings potential in the use of steam. If steam is injected in the right phase during the dishing process, steam could replace the heating of water in the final rinse stage, which is a major part of the dishwashers’ electricity usage. The distribution of steam, the final temperature after steam injection and steam injection time are factors whose impact this study will examine.

    In this study, mostly practical tests have been conducted. To ensure which parameters will affect the gloss the tests have been conducted with whole dish cycles. The dishwasher that has been used is an Asko D5434, and the dishwashers’ control card has been programmed especially for these tests. The Normal wash program was the dish program used during this study since it was used during the energy labelling of the dishwasher. The Normal wash program has been reprogrammed so that there will be no heating of the water in the final rinse stage. Before each test the temperature and relative humidity of the surroundings have been noted, an average value for the water hardness has been calculated and a certain amount of detergent has been measured for every test. Five different types of dishes all made of glass, have been used as test subjects and after each test the dishes glossiness have been assessed with a light box. For the production of steam, either one or two steam generators have been used. During the tests the temperature in the dishwasher has been registered and both the electricity usage and the water usage have been noted. For the sake of comparison, reference tests were conducted with the ordinary Normal wash program and rinse aid.

    According to the results of the study, steam can be used as rinse aid as it is even better for gloss than ordinary rinse aid. Clearly, it is important for the distribution of steam where in the dishwasher steam is injected and there is also a connection between gloss and steam injection time. During the course of the study, certain discoveries where made regarding the reprogrammed Normal wash programs’ usage of water and electricity. Hence, adjusted values were calculated in order to provide a fair comparison with the results from the reference tests. According to the adjusted values, the water usage with steam injections will increase somewhat if steam were to be used in the Normal wash program. However, the adjusted values show that the dishwashers’ electricity usage can be greatly reduced if steam is to be used to raise the temperature before the drying phase instead of the dishwashers’ radiator.

    Aside from providing nice gloss, there are other advantages as well with steam. To eliminate the usage of ordinary rinse aid will decrease the amount of chemicals released into the environment and should the Normal wash program with steam be reprogrammed correctly, a lot of electricity could be saved. Further research regarding steams’ impact on drying dishes is recommended.

  • 244. Larsson, Sarah
    et al.
    Dragic, Tamara
    Elproduktion från lågvärdig spillvärme med ny teknik; ECT-processen: Modellering och jämförelse med Organic Rankine Cycle2016Independent thesis Advanced level (degree of Master (One Year)), 300 HE creditsStudent thesis
    Abstract [en]

    The constantly growing population in the world is putting more and more pressure on the earth and its natural resources. Meanwhile, the use of fossil fuels keeps creating carbon dioxide emissions that accelerates the global warming. Therefore, it is becoming increasingly important to conserve the earth’s resources and to search for alternative fuels that can replace the fossil fuels. The use of low grade waste heat, which is a by-product of industrial processes, has gained a lot of attention in the last decades. To prevent this heat from going to waste, it can be used to generate electricity. The Organic Rankine Cycle (ORC) is the most common technique to achieve this. The new technique that is evaluated in this study is called the ECT-process and is a development of the ORC-process.

     

    The ECT-process can approximately be described as three separate ORC-cycles that uses the same waste heat flow. In this study, low grade waste heat is defined as heat with a temperature at 60-200 oC and is, during the ECT-process, cooled down to a temperature at 20-50 oC. In the industry, the waste heat often exists as warm fluids or flue gases and therefore, both types have been evaluated. The refrigerant used as heat carrier in the process is R134a.

     

    The purpose of this study is to compare these techniques with respect to thermal efficiency, generated electricity and heat exchange area, to provide a picture of the performance of the ECT-process, compared to the ORC-process. Climate impact, considering emissions of carbon dioxide equivalents and the refrigerant’s impact is taken into consideration. The electricity generated by the ECT-process is expected to replace fossil-based margin electricity. An economic analysis of the ECT-process is made with respect to component cost. The cost for vaporization system, condensers and the refrigerant is calculated with a payback period of three years. The cost for pumps and turbines is unknown and its cost is to be covered by the net profit for the technique.

     

    The goal with this study is to verify the ECT-process with respect to use and cost, to facilitate a commercialization of the technique. A comparison with existing techniques is made to prove that this process has potential to use waste heat more efficiently and thereby produce more electricity.

     

    Results show that the ECT-process is better than the ORC-process both when considering thermal efficiency and electricity generation. It requires a smaller heat exchange area which contributes to a lower component cost. A greater electricity production also means that a greater deal of margin electricity can be replaced. When the waste heat is made up from flue gases, a larger heat exchange area is required which contributes to a larger component cost. Therefore, only waste heat in the form of warm fluids should be used.  

     

    The ECT-process shows better results than the ORC-process with respect to all investigated criteria but is limited by the refrigerant and therefore, further studies to find an appropriate replacement for R134a is recommended. The same scenario doesn’t always give the best result when all the criteria are considered. From an economic perspective it is for example desirable to have a small difference between the inlet- and outlet temperature of the waste heat. However, this scenario produces the least amount of electricity, which then contradicts the purpose of the ECT-process. That is why it is important to consider all the criteria when evaluating the ECT-process. 

  • 245.
    Lin, Wamei
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Nilsson, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Malutta, Raffaelle
    Waste heat recovery by organic rankine cycle (ORC) for moist exhaust gases from paper industry2017In: ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), American Society of Mechanical Engineers (ASME) , 2017, Vol. 6Conference paper (Refereed)
    Abstract [en]

    Large potential exists in recovering waste heat from paper industry processes and machinery. If the overall energy efficiency would be increased, it could lead to significant fuel savings and greenhouse gas emission reduction. The organic Rankine cycle (ORC) system is a very strong candidate for converting low-grade waste heat into power. However, there is a lot of water vapor containing latent heat in the exhaust gases from the drying process in the paper industry. Thus, the aim of this research work is to increase the efficiency of the ORC system by recovering not only the sensible heat but also the latent heat from the exhaust gases in the paper drying process. In order to recover the latent heat from the moist exhaust gases, one idea of this article is to introduce a direct contact condensing unit into the ORC system. The performance of ORC system with the direct contact condensing unit was analyzed by using the CHEMCAD software. A case study was conducted based on data of the exhaust gases from a tissue production / drying machine. Latent heat will be recovered when the evaporating temperature of the ORC working fluid is lower than the dew point of the water vapor in the exhaust gases. The results showed that the available heat load was increased when the evaporating temperature was reduced. Furthermore, a performance comparison of the ORC systems with and without the direct contact condensing unit was carried out in the case study as well. The results showed that the ORC system with the direct contact condensing unit not only could recover latent heat from the water vapor in the exhaust gases but also could have a small size and small volume evaporator in the ORC system.

  • 246.
    Lindborg, Jenny
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Solceller utsatta för partiell skuggning: Jämförelse mellan olika systemkonfigurationer2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The effects of global warming has lead to a temperature rise in the atmosphere. Many countries have agreed to reduce the greenhouse gas emissions in order to mitigate climate change. The energy production today is highly dependent on fossil fuels and thus one solution to reduce emissions is to use more renewable resources. Solar cells are today growing on the market and in Sweden one can expect that solar energy will represent 5 – 10 % of the electricity production in year 2040. Partial shading is still a problem causing losses in the electricity production for solar cells. To reduce the losses due to shading bypass-diodes are built-in on modules. Further successful method can also be to change the interconnections among moduls in a system. At the time of writing this paper, configurations with series-parallel connections between modules are most commonly used, but during partial shading it has been shown that increasing interconnections can increase the outgoing effect.

    The purpose of this study was to show guidelines for the investor of solar cells, who plans an installation near objects that will creates shadows on the cells. The target consisted of two parts. First, there was an experimental objective which compared two different system configurations where the solar modules first were connected in series and thereafter in “Total Cross Tied”. The other part of the study considered a theoretical simulation to answer questions as how the energy production during a year was changed for a solar panel by placing it near a chimney. Thereafter it should also state guidelines on how to place the panel around the chimney so that the shading effects are no noticeables.

    The experiments were done outdoors and the system consisted of sixteen monocrystalline solar panels. First the panels were connected in series (S) and thereafter in “Total Cross Tied” (TCT). The system included also an inverter that changed direct current from the solar panels to alternating current. In the first experiment the electricity produced from the systems was measured, whereof one module was exposed to different types of shading. As a final experiment, one module was separated from the system where is was exposed to the same shading pattern as before.

    The results showed that the PV systems had an efficiency of 16 % for an irradiance between 400 – 700 W/m2. For lower irradiances than 400 W/m2 and higher than 700 /m2 the systems experienced a decreasing efficiency of about 1 – 2 %. A high irradiance occurs normally during the middle of the day when the solar cells have a higher temperature, which decreases the efficiency.

    The experiments proved that shading more cells so that current will flow through more bypass diodes resulted in a lower electricity production. For example if only one bypass diode is activated it means that the remaining cells that are not connected to that bypass diode can work freely and gets a higher maximum power point (MPP) on the IU characteristics. When a module got completely shaded it reduced the electricity output power with 7,72 % for the system with series connected modules. For the TCT-configuration the system experienced a reduction of 13,87 %. These results may be a contradiction according to previously research. A conceivable explanation is that the TCT-configuration produces higher current, which can exceed the allowed value for a functionally bypass diode. If the current in a shaded module flows through its bypass diodes it results in a short-circuit of the module so that it cannot contribute to the voltage. The more parallel PV arrays a system includes, a higher effect loss will occur since the unshaded strings may experience an identical voltage drop as the shaded one. The TCT-configuration included two strings connected in parallel.

    The sensitivity analysis where one module was separated from the whole system showed nearly the same results as for the whole system. Placing the shading object far away from the module resulted in a higher electricity production for some tests, as it is only the direct radiation that disappears.

    The simulations results were expressed in terms of “shading performance” and it showed how much a shaded solar module produced compared to an unshaded. It was shown that the parameters that had the biggest influence on the results were the height of the chimney and how far the solar module was placed with respect to the chimney. As a worst-case scenario, the shading performance was 41 % for a series-connected module. This was for a chimney with 2 m of height that placed next to the solar module.

    The results indicated that having a higher chimney had a decreasing effect of the shading performance for the solar module. To get a higher shading performance one can choose to place the solar cells at a larger distance from the chimney. Conclusively, placing the solar module so that the chimney is located to the south of the module the shadow will affect the panel more, and a longer distance is therefore needed. If the solar cells are located on a distance that is at least 0,3 m from a shading object with a height of 0,5 m, it means that the solar cells will produce 95 % of what that would have given unshaded. For a shading object with a height of 2 m it means that the solar cells must be placed at a distance of 2,1 m from the object.

  • 247. Lindgren, K.
    et al.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Entropy Production in a Chaotic Chemical System1986In: Zeitschrift für Naturforschung, 41a, 1111-1118Article in journal (Refereed)
    Abstract [en]

    The average rate of entropy production in a homogeneous chemical system is investigated in oscillating periodic and chaotic modes as well as in coexisting stationary states. The simulations are based on an abstract model of a chemical reaction system with three freely varying concentrations. Five concentrations are assumed to be kept constant by suitable flows across the boundary. A fixed concentration is used as a control parameter. Second order mass action kinetics with reverse reaction is used. An unexpected result is that periodic modes in some windows in the chaotic interval have higher average rate of entropy production than the surrounding chaotic modes. A chaotic mode coexists with a stable stationary state with smaller entropy production. A unique (unstable) stationary state produces more entropy than the corresponding oscillating mode

  • 248.
    Lindh, Helena
    et al.
    Lund Univ, Dept Design Sci, Packaging Logist, SE-22100 Lund, Sweden..
    Williams, Helen
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Olsson, Annika
    Lund Univ, Dept Design Sci, Packaging Logist, SE-22100 Lund, Sweden..
    Wikstrom, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Elucidating the Indirect Contributions of Packaging to Sustainable Development: A Terminology of Packaging Functions and Features2016In: Packaging technology & science, ISSN 0894-3214, E-ISSN 1099-1522, Vol. 29, no 4-5, p. 225-246Article in journal (Refereed)
    Abstract [en]

    Packaging has great potential to contribute to sustainable development through its functions. Previous research has indicated a need for increased knowledge among consumers, suppliers, authorities and media of how packaging functions and features influence sustainable development. Previous research also shows the need for a common terminology of packaging functions and features in order to facilitate and improve communication and understanding in development and decision processes. This conceptual paper sets out to identify, collect, analyse and systemize packaging functions and features and evaluate them based on their indirect contributions to sustainable development. The systemized functions and features are expressed in generic terminology. Three clusters of packaging functions were identified from the literature: protect, facilitate handling and communicate. Nineteen packaging features were also identified. They were grouped under the three functions and elaborated based on their indirect contributions to the environmental, social and economic dimensions of sustainable development. Fourteen potential positive indirect effects were identified including decreased product waste, reduced risk for human health hazards, increased handling and transport efficiency. Decreased product waste was generated by 13 of the features and was thus the most frequently appearing. Reducing waste is thereby indicated to be a manifold matter, but also one of great potential. The proposed terminology can contribute to an increased understanding of how packaging can actually contribute to sustainable development. In a theoretical context, this paper attempts to complement earlier work in sustainable packaging development by its emphasis on the indirect contributions of packaging to sustainable development.

  • 249.
    Lund Björnås, Kristine
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Spatially explicit models: planning salmonid habitat restoration in regulated rivers2019Report (Other academic)
  • 250.
    Lundin, Lucas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Karlsson, Simon
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Barriers and opportunities for implementation of a return system for industrial packaging: A case study at Valmet AB2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sustainability has become a more and more important aspect within companies worldwide. Environmental aspects within companies are often connected to higher profits and increased corporate image. One field of importance, to create a more effective supply chain within companies, regards to the logistic process. An area within logistics is reverse logistics, which regards to the activities related to taking back goods, information or material from the consumer or customer to receive value from it or to dispose it. By reusing goods or material, reverse logistics together with handling solutions could form a return system. Implementation of a return system could moreover be related to circular economy, which means effective use of resources within a closed loop supply chain. By combining logistics, handling, return system and circular economy, a more effective supply chain could be achieved.

    The study aims to create a theoretical framework on how barriers can hinder implementation of a return system and to identify potential solutions. This is done by investigating two research questions, namely how industrial packaging is handled today and further to investigate the barriers and opportunities for a return system. The questions and the aim will be answered through a case study of the company Valmet AB where internal documentation has been examined and interviews has been conducted. In addition to this, theory has been reviewed and a life-cycle assessment has been performed to examine possible benefits of a return system.

    The study shows that there exist barriers and opportunities, where some of them are mentioned in the existing theory while others are scarcely investigated. In the relevance to previous research, new barriers that need further investigation have been identified, in relation to the studied industry. These are lack of internal communication, lack of time and location barriers. Moreover, the study shows that there exists environmental incentive for implementation of a return system. However, it is hard to guarantee economic profit, since there are unknown costs due to storage, personnel and refurbishing. Future research should further examine the new barriers in the context of combined theoretical dimensions.

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