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  • 1.
    Aftab, Mohammad Adnan
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Biofuel, An alternative source for jet fuel in Aviation2017Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The transport industry is one of the fastest growing industries with the sector playing a significant role in negative impact on global warming and pollution through the emission of greenhouse gases. Aviation in particular, has enjoyed growth especially in the few decades. New airlines and aircraft manufacturers are coming up with different innovations and technologies to ensure they make the best possible environmentally friendly aircraft. The new main area of focus has been on how to come up with fuel that will reduce the greenhouse gas-emissions. The stakeholders in the same effort include developed nations like the United States, United Kingdom, Russia, France, Germany, and Canada among others. Energy providers as well as jet fuel suppliers are also making efforts to conserve the environment. The purpose of this thesis is to explore the area of biofuel in aviation by looking into various stakeholders involved in the efforts of the transition from fossil fuel to biofuel. The conclusion of this thesis is that biofuels are viable options in the aviation industries since there have been positive results in the tests made. 

  • 2.
    Alex, Ansu
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Comparison study of various current and potential liquid biofuels in road freight transport: Application on a case study on Transport Centralen in Halmstad2017Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The role of liquid biofuels in transportation to minimize the effects of climate change is  evident and has led to a number of studies on finding effective solutions to replace fossil fuels. Liquid biofuels are especially important for heavy duty transports as the effective ‘green’ alternatives are not as many compared to light duty vehicles; for which for e.g. electrification is an option. This thesis presents a comparison study of 8 liquid biofuels with a total of 13 different fuel pathways for use in road freight transports; both current and potential future fuels are assessed in terms of their environmental effects, fuel properties and compatibility with the heavy duty vehicle engines (see Table 10, page 36). Furthermore, a case study is performed to assess the practicality of the results of the study.  Hydro-treated vegetable oil, Bio Dimethyl ether, Liquefied Bio Methane/ ED95 are identified as fuels with considerable potential in the shorter term. Algal biofuel and Biomass to liquid (BTL) fuels from synthesis gas, if realized commercially would be a breakthrough for biofuels in overall transportation sector. However, life cycle analysis has to be performed for the different fuel pathways to completely understand the various impacting factors.

  • 3.
    Alkiswani, Mutaz
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Spectrum conversion in solar cells industry: Novel model concept and steps towards commercialization2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Solar photovoltaic industry is a hot research field, massive attempts are going on all over the world to increase its productivity in different ways. One of the challenges for solar cells is the light spectrum mismatch losses, which referred to the part of solar spectrum that cannot be utilized to electricity by the conventional cells.

    Two ways have been suggested to overcome solar spectrum mismatch losses, the first is multi layered cells (tandem cells) with a different light behavior for each layer, and the second is spectrum conversion which is this researches subject.

    Spectral modification or conversion in solar cells industry has been studied and different lab scale models have been introduced. According to nanoscale journal, such technology may be the base of the next generation solar cells, mentioning specifically the use of luminescence down conversion and up conversion techniques to control the light spectrum on the solar cell, these endeavors targets to produce solar cells that is not subjugated to Shockley-Queisser maximum efficiency limit of 31%.

    This research aims to draw a map of various ideas introduced to incorporate similar technologies in solar cell products, beside further suggestion to enhance its technical behavior and to push the commercialization of the technology forward. This is expected to reveal clear image about technology’s future development map for the upcoming studies, and to create a motivation for further studies towards a commercial production scale.

    The proposed commercialized model will result in enhancing the maximum theoretical efficiency limit to 48% if all spectral mismatch loses have been eliminated. Quantum energy level diagrams have been illustrated to describe each model’s performance under a theoretical light spectrum.

  • 4.
    Al-Mimar, Samer
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap. Halmstad University.
    Integration of solar and wind power at Lillgrundwind farm.: Wind turbine shadow effect on solar farm atLillgrund wind farm.2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The supply of energy is a key factor in modern societies. As the old fossil sources for energy are dwindling, conflicts arise between competing nations and regions. Fossil energy sources also contribute to the pollution of the environment and emission of greenhouse gases.

    With renewable energy sources many of these drawbacks with fossil fuels can be eliminated as the energy will be readily available for all without cost or environmental impact.

    Combining the renewable energy sources will be very effective, particularly in commercial areas where lake of electricity is high. The cost of combining onshore wind and solar power plant is affordable. Furthermore there is no power failure or load shedding situation at any times. When it is manufactured in a large scale, cost of this integrated natural resources power generation system is affordable. Moreover there is no power failure or load shedding situation at any times. Therefore, it is the most reliable renewable power or electricity resources with less spending and highly effective production. ref [1].

    The thesis work would take planning of offshore renewable plant (Lillgrund) with considering the resources of renewable power. The study would take in account combining the Lillgrund wind farm with solar system and take close look into the advantage and disadvantage of combining the renewable resources together and figure out if such station can work in proper way and provide sufficient power production. The study would take in account the effect of each resource on other resource, also calculations would be done.

    The study site is Lillgrund in south of Sweden. The Lillgrund wind farm is the most important offshore wind power plant installed in Sweden with a total capacity of 110 MW, corresponding to 48 turbines. ref [2].

  • 5.
    Al-samuraaiy, Omar
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Efficiency comparison between Heat Pump andMicro CHP located in two different location inSweden2016Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Efficiency of a ground source heat pump with thermal capacity of 6 kW determined in two differentlocations in Sweden. In the north side with low average temperature which could go down to -10 ᵒCand in the south side, with low average temperature with +2 ᵒC. The heat pump has refrigerantR407c, which could be connected to both, ground source heat feeding methods the horizontal, andthe vertical model. The heat pump give heat for both space heating and domestic hot watercompared the micro CHP which has thermal capacity of 12.5 kW and electrical capacity of 4.4 kW. Ithas IC engine which means the engine has internal combustion work. It also works with two kinds offuel, natural gas and propane MOZ 92; the energy and exergy of the fuel in micro CHP feeding thethermal process by heat. That heat used for space heating and domestic hot water after going outthe process for the cooling which keep the heat in storage tank and it heat the liquid to the gas to beused in the turbine to produce the electricity. The two locations in the north and south of Swedenwill influence the thermal operation and that influence power used for compressor for heat pumpand somehow the pump in the micro CHP. The study shows that the different in exergy and energyefficiency between these two heat technologies by located them in the locations. Higher efficiencyof the micro CHP which give the advantage of use Micro CHP some technology give the benefit byusing the fuel for producing the heating and electricity , the benefit which give the customer manybenefit shows in the study. That’s comparing with the heat pump which is large use in Sweden. Inthis paper will introduce Micro CHP as heating technology which has been used in the rest of Europecould be used in Sweden for future heating technology with electricity producing, shall change thecostumer from energy consumption costumer to producing costumer.

  • 6.
    Andersen, Niklas
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Ismail, Zahir
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Solel från ljudbarriär: längs Annetorpsvägen i Hyllie, Malmö2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.

    The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers. Along distance A, a PVNB with a total capacity of 19 kWp is expected to generate 18 000 kWh per year assuming realistic shadowing, which equals 6% losses compared to production without shadows. The PVNB along distance B with installed capacity of 37 kWp has no considerable problems with shadowing and is expected to generate 37 500 kWh per year. This gives a total production of 56 500 kWh per year.

    The combined investment costs (excluding costs for the actual noise barrier) for both power plants are assumed to be approximately one million SEK. Expected economical outcome is a negative capital value after 25 years, although a change of critical factors such as investment aid, investment cost, electricity prices and cost of capital may result in a more positive outcome. Production losses from shadowing and dirt seem to have a minimal effect on the outcome

    Despite uncertainty in the economical outcome, realizing the project would have several other positive effects such as reduction of carbon dioxide emissions and a positive impact on the public view of renewable energy.

  • 7.
    Andersson, Gustav
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Ericsson, Emil
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Dark Ages Interferometer (DALI) Deployment Rover: Energy System2014Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    The cosmic “Dark Ages” is the cosmic era between the epochs of recombination of cosmic microwave background and the formation of the first stars. The only signal from this epoch is from neutral hydrogen, which could represent one of the richest data sets in cosmology. In order to extract this data, NASA/JPL has proposed a rover mission to the farside of the moon to deploy several radio arrays. Here the arrays would gather data undisturbed by human interference. This thesis examines the possibility of using photovoltaic and electric batteries as an energy solution for a rover on the moon. The requirement for such a system to survive on the moon is discussed in a literature study. A proof of concept simulation using a Simulink model has also been done. The thesis concludes that a rover can deploy the radio array using solar energy. It would be able to hibernate through the night using radioisotope heating. It would need to wait for its batteries to charge before each night.

  • 8.
    Andreasson, Tobias
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Lindh, Emelia
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Förnybar energi på Svalbard2018Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    This degree thesis investigates the possibilities of producing food inside a container at Svalbard, using renewable energy and energy storage. The idea was to be able to place the container at remote places without the need of being connected to the grid. We chose Svalbard, where it is cold and the sun is shining 24 hours a day at summertime. In the winter the opposite occurs and the sun is absent from the sky.

    The work is divided into theoretical studies and results based on different calculations. Such as economical evaluations (LCOE), and simulations using the computer programs Matlab and PVsyst. We have investigated if solar power and wind power is suitable as energy sources. Options for storage were batteries, grid and hydrogen storage. Different cases with Photovoltaics- and wind power plants, with batteries or grid, were compared against each other. It is not possible to use the grid as storage. This resulted in different sizing of our cases, with no excess energy production. The result showed that a 5 kWp photvoltaic plant with dual axis tracking system, was the most profitable. The Pay off would be 14 years and the total profit 63 453 SEK. If it will become possible in the future to use the grid at Svalbard as storage, it will open up opportunites for bigger systems. This will lead to higher profit than with smaller ones. Our results show that it is now most profitable with solar power.

  • 9.
    Averfalk, Helge
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Ingvarsson, Paul
    ÅF, Division Industry, Stockholm, Sweden.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Gong, Mei
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Large heat pumps in Swedish district heating systems2017Inngår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 79, s. 1275-1284Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Power-to-heat solutions like heat pumps and electric boilers are foreseen to be possible future tools to stabilise international power markets with high proportions of variable power supply. Temporary low cost electricity can be used for heat generation at times with high availability of wind and solar power through substitution of ordinary heat supply, hence contributing to increased energy system sustainability. Power-to-heat installations in district heating systems are competitive due to low specific investment and installation costs for large electric boilers, heat pumps, and heat storages. Several large-scale heat pumps were installed in Swedish district heating systems during the 1980s, since a national electricity surplus from new nuclear power existed for some years. The aim of this paper is to summarise the accumulated operation experiences from these large Swedish heat pumps to support and facilitate planning of future power-to-heat solutions with heat pumps in district heating systems. Gained experiences consider; installed capacities, capacity utilisation, heat sources used, refrigerant replacements, refrigerant leakages, and wear of mechanical components. The major conclusion is that many of the large thirty-year-old heat pumps are still in operation, but with reduced capacity utilisation due to internal competition from waste and biomass cogeneration plants in the district heating systems.

  • 10.
    Averfalk, Helge
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Ingvarsson, Paul
    ÅF, Division Industry, Stockholm, Sweden.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    On the use of surplus electricity in district heating systems2014Inngår i: Proceedings from the 14th International Symposium on District Heating and Cooling: September, 6-10, 2014: Stockholm, Sweden / [ed] Anna Land, Stockholm: Swedish District Heating Association , 2014, s. 469-474Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Maintained balance between supply and demand is a fundamental prerequisite for proper operation of electric power grids. For this end, power systems rely on accessibility to various balancing technologies and solutions by which fluctuations in supply and demand can be promptly met. In this paper, balancing approaches in the case of surplus electricity supply, due to long-term, seasonal, or short-term causes, are discussed on the basis mainly of compiled experiences from the Swedish national power grid. In Sweden, a structural long-term electricity surplus was created in the 1980s when several new nuclear plants were commissioned and built. One of four explicit domestic power-to-heat solutions initiated to maximize the utilization of this surplus electricity, as export capacities were limited, was the introduction of large scale electric boilers and compressor heat pumps in district heating systems. In retrospective, this solution not only satisfied the primary objective by providing additional electricity demand to balance the power grid, but represents today – from an energy systems perspective – a contemporary example of increased system flexibility by the attainment of higher integration levels between power and heat sectors. As European power supply will be reshaped to include higher proportions of fluctuating supply technologies (e.g. wind and solar), causing occasional but recurring short-term electricity surpluses, the unique Swedish experiences may provide valuable input in the development of rational responses to future balancing challenges. The main conclusions from this study are that district heating systems can add additional balancing capabilities to power systems, if equipped with electrical heat supply technologies, hereby contributing to higher energy system flexibility. Consequently, district heating systems also have a discrete but key role in the continued integration of renewable intermittent power supply technologies in the future European energy system.

  • 11.
    Basavalingappa, Sharat
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Grid-Tied Solar Photovoltaic (PV) System with Battery storage: A Brief Techno-Economic Analysis2019Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Most of the world’s electricity is being generated through conventional sources of energy like coal and nuclear. People are realizing the dire effect of using these fuels, and the amount of CO2 being released into the environment. Therefore, in recent year there has been a shift in emphasis towards cleaner ways of generating electricity. One such recent trend is solar photovoltaics (PV), which has seen rapid growth over the years. This ever-increasing trend of adopting PV system allows consumers to be producers or “Prosumers”. Due to the irregular production capability of solar PV, the need for an energy storage system like a battery bank is on the rise as well. This report evaluates how solar PV can be used in combination with a battery bank to supply the annual electricity demand for a household with little to no support from the grid. The building is assumed to be located in Bangalore, India. The energy demand for the household is estimated based on the requirements of a basic Indian house standard. The size and configuration of each component have been done with regards to the total load demand. Furthermore, the cost of the whole system is estimated in order to evaluate the feasibility of the grid-tied system from an economic perspective. The results show that a PV system consisting of four 270W solar panels, a battery bank of eight150Ah lead-acid batteries and a 48V 4kW inverter is required to meet the annual energy demand of the house. The results show that from a technical standpoint, the above-mentioned technology is feasible. The results from the economic evaluation show that the localized cost of energy(LCOE) for the system is ₹6.01/kWh or € 0.078/kWh or 0.84SEK/kWh and the payback time for the given system is 16.19 years. On the bright side, there are new technological advancements in the PV field every day, which could mean that an energy system of this type can be an achievable and practical alternative.

    Most of the world’s electricity is being generated through conventional sources of energy like coal and nuclear. People are realizing the dire effect of using these fuels, and the amount of CO2 being released into the environment. Therefore, in recent year there has been a shift in emphasis towards cleaner ways of generating electricity. One such recent trend is solar photovoltaics (PV), which has seen rapid growth over the years. This ever-increasing trend of adopting PV system allows consumers to be producers or “Prosumers”. Due to the irregular production capability of solar PV, the need for an energy storage system like a battery bank is on the rise as well.

    This report evaluates how solar PV can be used in combination with a battery bank to supply the annual electricity demand for a household with little to no support from the grid. The building is assumed to be located in Bangalore, India. The energy demand for the household is estimated based on the requirements of a basic Indian house standard. The size and configuration of each component have been done with regards to the total load demand. Furthermore, the cost of the whole system is estimated in order to evaluate the feasibility of the grid-tied system from an economic perspective.

    The results show that a PV system consisting of four 270W solar panels, a battery bank of eight 150Ah lead-acid batteries and a 48V 4kW inverter is required to meet the annual energy demand of the house. The results show that from a technical standpoint, the above-mentioned technology is feasible. The results from the economic evaluation show that the localized cost of energy (LCOE) for the system is ₹6.01/kWh or € 0.078/kWh or 0.84SEK/kWh and the payback time for the given system is 16.19 years. On the bright side, there are new technological advancements in the PV field every day, which could mean that an energy system of this type can be an achievable and practical alternative.

  • 12.
    Berg, Nichlas
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Kårhammer, Per
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Säsongslagring av spillvärme: Ersättning av Halmstad fjärrvärmenäts spetslastanläggning2013Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I Sverige används mycket energi för uppvärmning av bostäder och lokaler. För att uppfylla det ständigt ökande behovet av värme, byggs exempelvis nya värmeproducerande anläggningar som komplement i fjärrvärmesystem. Samtidigt finns det outnyttjad energi i industrin som i sin produktion får värme som oönskad biprodukt.

    Denna rapport undersöker möjligheten att utnyttja denna biprodukt från industrin för att tillföra energi till ett befintligt fjärrvärmenät och lagra i ett säsongsvärmelager. När värmebehovet ökar under den kalla delen av året, skall säsongsvärmelagret bidra med värme.

    Idén är att lagret skall ersätta delar av de värmeproducerande anläggningarna som utnyttjas i Halmstads fjärrvärmesystem. Målet är att all fossil bränsleanvändning skall kunna tas bort. Rapporten undersöker även ekonomiska lönsamheten samt miljövinsten i att ersätta del av biobränsleanvändningen.

    I Halmstad finns ett stålverk, Höganäs Halmstadverken, som kan bidra med överskottsenergi i form av värme. Rapporten genomför beräkningar på industrins potential att leverera prima värme till fjärrvärmenätet.

    Med hjälp av beräkningar och simuleringar i Microsoft Excel tas ett system med lämplig lagringsmetod samt spillvärme från lokal industri fram. Detta system skall optimeras med hänsyn till ekonomiska och miljömässiga förutsättningar.

    Resultatet visar att Halmstads förutsättningar är goda för att integrera ett groplager samt att det finns potential att leverera spillvärme från Höganäs Halmstadverken. Storlekarna på vattenburna säsongsvärmelager optimeras till 200 000 m3 för ersättning av endast fossila bränslen respektive 550 000 m3 för ersättning av fossila och biobränslen. Spillvärmeeffekten från Höganäs Halmstadverken beräknas till 15 MW.

    De ekonomiska kalkylerna resulterar i en årlig vinst på upp till 8 miljoner kronor med en payoff-tid på 8 år. Den totala miljövinsten i minskade växthusgasutsläpp blir 4 800 ton koldioxidekvivalenter per år.

  • 13.
    Berkan, Yaroslav
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Simris lokala energisystem2018Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
  • 14.
    Connolly, David
    et al.
    Aalborg University, Aalborg, Denmark.
    Lund, Henrik
    Aalborg University, Aalborg, Denmark.
    Mathiesen, Brian Vad
    Aalborg University, Aalborg, Denmark.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Möller, Bernd
    Aalborg University, Aalborg, Denmark.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Boermans, Thomas
    Ecofys, Köln, Germany.
    Trier, Daniel
    PlanEnergi, Copenhagen, Denmark.
    Østergaard, Poul Alberg
    Aalborg University, Aalborg, Denmark.
    Nielsen, Steffen
    Aalborg University, Aalborg, Denmark.
    Heat Roadmap Europe: Combining district heating with heat savings to decarbonise the EU energy system2014Inngår i: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 65, s. 475-489Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Six different strategies have recently been proposed for the European Union (EU) energy system in the European Commission’s report, Energy Roadmap 2050. The objective for these strategies is to identify how the EU can reach its target of an 80% reduction in annual greenhouse gas emissions in 2050 compared to 1990 levels. None of these scenarios involve the large-scale implementation of district heating, but instead they focus on the electrification of the heating sector (primarily using heat pumps) and/or the large-scale implementation of electricity and heat savings. In this paper, the potential for district heating in the EU between now and 2050 is identified, based on extensive and detailed mapping of the EU heat demand and various supply options. Subsequently, a new ‘district heating plus heat savings’ scenario is technically and economically assessed from an energy systems perspective. The results indicate that with district heating, the EU energy system will be able to achieve the same reductions in primary energy supply and carbon dioxide emissions as the existing alternatives proposed. However, with district heating, these goals can be achieved at a lower cost, with heating and cooling costs reduced by approximately 15%. © 2013 Elsevier Ltd.

  • 15.
    Connolly, David
    et al.
    Department of Development and Planning Aalborg University, Aalborg, Denmark.
    Lund, Henrik
    Department of Development and Planning Aalborg University, Aalborg, Denmark.
    Vad Mathiesen, Brian
    Department of Development and Planning Aalborg University, Aalborg, Denmark.
    Möller, Bernd
    Department of Development and Planning Aalborg University, Aalborg, Denmark.
    Østergaard, Poul Alberg
    Department of Development and Planning Aalborg University, Aalborg, Denmark.
    Nielsen, Steffen
    Department of Development and Planning Aalborg University, Aalborg, Denmark.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Trier, Daniel
    PlanEnergi, Copenhagen, Denmark.
    The role of district heating in decarbonising the EU energy system and a comparison with existing strategies2013Inngår i: Book of Abstracts: 8th Conference on Sustainable Development of Energy, Water and Environment Systems, 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Many strategies have already been proposed for the decarbonisation of the EU energy system by the year 2050. These typically focus on the expansion of renewable energy in the electricity sector and subsequently, electrifying both the heat and transport sectors as much as possible. In these strategies, the role of district heating has never been fully explored system, nor have the benefits of district heating been quantified at the EU level. This study combines the mapping of local heat demands and local heat supplies across the EU27. Using this local knowledge, new district heating potentials are identified and then, the EU27 energy system is modelled to investigate the impact of district heating. The results indicate that a combination of heat savings, district heating in urban areas, and individual heat pumps in rural areas will enable the EU27 to reach its greenhouse gas emissions targets by 2050, but at a cheaper price than a scenario which focuses primarily on the implementation of heat savings.

  • 16.
    Deutschmann, Oliver
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Johansson, Thomas
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Framtidens elbilar utmanar nutidens elnät: Påverkan av ett ökat antal elbilar på ett halländskt elnät2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The challenges facing low voltage grids are rising as an increasing number of domestic houses transition from fossil fueled heating to electricity based heating. Several environmental goals and visions have the same transition from fossil based power to electricity based power in mind for the transportation sector. One of the most important tools for this transformation is widely regarded to be the electric vehicle. With the demands of the electric vehicle pressuring the power grid, several questions arise regarding the growth of the electric vehicle market and what repercussions it may have on the grid. This paper focuses on a typical low voltage grid in southern Sweden and what effects a growing electric vehicle market may have on it. Through computer-assisted simulations based on several future scenarios regarding the EV market, this paper finds that few modifications and reinforcements are needed on this particular grid within the next 10 to 15 years. After this timeframe the voltage drop becomes a serious concern and should be addressed.

  • 17.
    Farah, Hamad
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Hybrid solar system for heat and electric demands in a simple housing within Sweden and China2019Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The access to ideal heating and power techniques has always been highly thought after.This is mainly due to the development in housing architecture and the cold nature of certain regions which has led to an increase in popularity of the heating market and modernised heating technologies. The current DH systems make use of CHP plants for thegeneration of power and electricity. These CHP plants for the most part, are powered through biomass and during winter periods the demand for heating is highly increased.The biggest issue with relying on biomass solely is the constant need to burn wasteproducts which not only results in increasing the demand for consuming in more waste,but also results in producing remains (by-products) that cannot be broken down further and hence might require the utilization of land-space (landfills) for their disposal. Solar modules on the other hand, have gained increased popularity in the recent age. This is mainly due their extremely high flexible ability in converting solar irradiance intoelectrical and thermal energies. This study will try to provide a comprehensive study intothe utilization of a hybrid solar system that combines a standard PV module with a flat-plate collector through estimating the energy demands for a simple housing within Sweden and China. This will be the main aim of the study, however the possibilities of integrating this hybrid solar system alongside current DH systems will mostly be discussed in the first sections to proof the possibility of executing such a system. The theoretical work carried out will only include simulations of having just separate,standalone PV and flat-plate collector modules. However, designing a hybrid solar and DH system will not be the major focus of this study. The results at the end of the report,concluded that the electrical production for the Swedish case were noticeably higher thanthat of the Chinese case in spite of maintaining the same load values through both cases and higher solar irradiation for the Chinese case. Due to PVsyst simulation constraints,the results show that the investment cost of the Swedish PV (electrical component) module was about 3.6 times greater than that of the Chinese which could possibly mean that the Swedish case has a bigger PV module area than the Chinese case in order to meetel ectricity demand monthly. However, when it came to the thermal energy production, it was possible to assume different collectors cases and hence an area of 7m2 was chosen for the Swedish perspective while an area of 4m2 has been considered for the Chinese case. The thermal useful energy values where then compared with heating demands for both of the cases. Finally, the thesis concluded that there was no requirement for having an integrated DH network within the standalone houses, having small electricity and heat demand and hence, it might be more beneficial to have an integrated DH and solar system within more densely populated housing areas.

  • 18.
    Farouq, Shiraz
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS).
    Byttner, Stefan
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Gadd, Henrik
    Öresundskraft AB, Ängelholm, Sweden.
    Towards understanding district heating substation behavior using robust first difference regression2018Inngår i: Energy Procedia, Amsterdam: Elsevier, 2018, Vol. 149, s. 236-245Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The behavior of a district heating (DH) substation has a social and operational context. The social context comes from its general usage pattern and personal requirements of building inhabitants. The operational context comes from its configuration settings which considers both the weather conditions and social requirements. The parameter estimating thermal energy demand response with respect to change in outdoor temperature conditions along with the strength of the relationship between these variables are two important measures of operational efficiency of a substation. In practice, they can be estimated using a regression model where the slope parameter measures the average response and R2 measures the strength of the relationship. These measures are also important from a monitoring perspective. However, factors related to the social context of a building and the presence of unexplained outliers can make the estimation of these measures a challenging task. Social context of a data point in DH, in many cases appears as an outlier. Data efficiency is also required if these measures are to be estimated in a timely manner. Under these circumstances, methods that can isolate and reduce the effect of outliers in a principled and data efficient manner are required. We therefore propose to use Huber regression, a robust method based on M-estimator type loss function. This method can not only identify possible outliers present in the data of each substation but also reduce their effect on the estimated slope parameter. Moreover, substations that are comparable according to certain criteria, for instance, those with almost identical energy demand levels, should have relatively similar slopes. This provides an opportunity to observe deviating substations under the assumption that comparable substations should show homogeneity in their behavior. Furthermore, the slope parameter can be compared across time to observe if the dynamics of a substation has changed. Our analysis shows that Huber regression in combination with ordinary least squares can provide reliable estimates on the operational efficiency of DH substations. © 2018 The Authors. Published by Elsevier Ltd.

  • 19.
    Fältström, Mattias
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Ferdinandsson, Mikael
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Förutsättningar för absorptionskyla: Examensarbete på Öresundskraft2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Efterfrågan av kyla ökar i Sverige trots det kalla klimatet vilket då medför att behovet av fjärrkyla kan öka. Fjärrkyla är en centraliserad kylproduktion med fördelar som säkrare drift, minskade haverier samt att buller avlägsnas i jämförelse med lokala kylanläggningar. Således är absorptionskyla ett alternativ till fjärrkyla som börjar bli mer och mer intressant för fjärrvärmeintegrering. Syftet med rapporten är att ge företaget Öresundskraft ett underlag över de tekniska och ekonomiska förutsättningarna för absorptionskyla i Helsingborg. Problemställningarna har varit att undersöka: temperaturen på fjärrvärmen som ska användas till absorptionsanläggningen, hur absorptionsmaskinens kylfaktor påverkar förutsättningarna, hur absorptionsanläggningen ska dimensioneras, utreda olika placeringsalternativ för absorptionsanläggningen, om den befintliga ackumulatortanken kan användas i framtiden och om det är lönsamt att investera i en absorptionsanläggning. Problemställningarna besvarades genom intervjuer, sammanställning och beräkning av data, granskning av forskningslitteratur samt annan litteratur. Slutsatser som författarna har kommit fram till är att absorptionsmaskinen ska dimensioneras till 2,2 MW och att den ska placeras på Västhamnsverket. Under de förutsättningar att det fanns tillgång till billig värme samt att driften endast sker på sommaren fick resultatet ett utfall som gav lönsamhet i en absorptionsanläggning.

  • 20.
    Gadd, Henrik
    et al.
    Oresundskraft AB, S-25106 Helsingborg, Sweden..
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Fault detection in district heating substations2015Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 157, s. 51-59Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Current temperature levels in European district heating networks are still too high with respect to future conditions as customer heat demands decrease and new possible heat source options emerge. A considerable reduction of temperature levels can be accomplished by eliminating current faults in substations and customer heating systems. These faults do not receive proper attention today, because neither substations nor customer heating systems are centrally supervised. The focus of this paper has been to identify these faults by annual series of hourly meter readings obtained from automatic meter reading systems at 135 substations in two Swedish district heating systems. Based on threshold methods, various faults were identified in 74% of the substations. The identified faults were divided into three different fault groups: Unsuitable heat load pattern, low average annual temperature difference, and poor substation control. The most important conclusion from this early study of big data volumes is that automatic meter reading systems can provide proactive fault detection by continuous commissioning of district heating substations in the future. A complete reduction of current faults corresponds to approximately half the required reduction of the current temperature levels in the effort toward future low-temperature district heating networks. (C) 2015 The Authors. Published by Elsevier Ltd.

  • 21.
    Gadd, Henrik
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Thermal energy storage systems for district heating and cooling2015Inngår i: Advances in Thermal Energy Storage Systems: Methods and Applications / [ed] Luisa F. Cabeza, Cambridge: Woodhead Publishing Limited, 2015, 1, s. 467-478Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    The context for this chapter is the current use and typical applications of thermal energy storages within contemporary district heating and cooling systems in the Nordic countries. Examples include a new assessment method, distributed heat storages, and hourly, daily, weekly, and seasonal heat and cold storages. Specific sizes have been estimated for 209 heat storages and 9 cold storages.

  • 22.
    Ghadirinejad, Nickyar
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Design of an off-grid renewable-energy hybrid system for a grocery store: a case study in Malmö, Sweden2018Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    On planet Earth, fossil fuels are the most important sources of energy. However, these resources are limited and being depleted dramatically throughout last decades. Finding feasible substitutes of these resources is an essential duty for humanity. Fortunately, Mother Nature is providing us a number of good solutions for this crucial threat against our planet. Solar irradiance, wind blowing, oceanic and maritime waves are natural resources of energy that are capable of completely covering the annual consumption of all inhabitants on the Earth. In this research a set of components including “Northern Power NPS 100-24” wind generators, “Kyocera KD 145 SX-UFU” PV arrays, “Gildemeister 10kW-40kWh Cellcube” battery bank and HOMER bi-directional converter system were considered and successfully applied on HOMER tool and Particle Swarm Optimization (PSO) method. The main design goals of the presented hybrid system are to use 100% renewable energy resources in the commercial sector, where all power is produced in the immediate vicinity of the business place, adding strong advertising values to the setup. In order to supply hourly required load for a grocery store   (1000 ) in Malmö city with 115 kW peak load and 2002 kWh/d with maximum 0.1% unmet, the system was optimized to achieve minimum Levelized Cost of Energy (LCOE) and the lowest Net Present Cost (NPC). The HOMER simulation for quantitative analysis, along with a Particle Swarm Optimization (PSO) solution method is proposed and the results are compared. The results show that an optimized hybrid system with 3.12  LCOE, and power production of 28.5% by PV arrays and 71.5% by wind generators, is the best practice for this case study. 

  • 23.
    Ghebre, Temesghen Tesfazghi
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    The Viability of Installing Mid-Size PV Solar Parks in Sweden: "A paper that evaluates the economic viability of installing mid-size PV solar parks ranging from 250 kW to 2 MW in the village of Åled."2017Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The ambition of the Swedish government is rapidly concentrating on the development of the

    renewable energy systems especially on wind energy, bio energy and solar energy. It has been

    observed on the growth of the production of electricity and heat from these three mentioned renewable

    energy systems. But, relatively in Sweden the share of production of electricity obtained from PV is

    quite smaller than the other two. The PV electricity production in Sweden comprises in a large scale

    of mainly the grid connected distributed PV systems and with a small number of installed solar parks.

    The aim of this paper is to analyze the viability of installing mid -size PV solar parks in Sweden and

    to simulate the effect of the proposed project in the village’s (Åled is the village where the proposed

    site is located) and the country’s electricity production. This study includes designing, simulation and

    financial analysis of different grid connected centralized mid -size capacities of PV solar parks of 250

    kWp,500 kWp,1MWp and 2MWp. They are all fixed ground mounted systems. Moreover, it also

    discusses the main reasons that hinders decision makers, the PV complications that are connected to

    the grid, Sweden’s energy regulations particularly the emission regulation and the financial policies

    of PV. Also, study visit, telephone and email contacts have supplemented it.

    This study was done with the collaboration of Nyedal Solenergi, in which the proposed site was

    owned by the company and this paper will be a future guide for the investment of the mid-size PV

    solar park. According to the study a discussion has been made with the grid supplier (EON) in that

    area on the investment on one of the designed projects which are presented in this paper.

    The results of the study show that the effect of the proposed systems on the production of electricity

    in the village of Åled was between 2.68 – 21.4 % and the impact on the country’s PV electricity

    production was 0.2 – 1.58 %. And, the possibility of installing mid-size PV solar parks generally in

    Sweden particularly in the proposed site is possible and economically it is viable but not profitable

    for system capacities less than 1 MW. As the IRR found for all capacities is greater than the estimated

    WACC, hence each proposed capacity has the possibility of paying back all its investment costs in

    about 23 years. So, the profitability is very low in case of the 250 kWp and 500 kWp but for the others

    they have about 7-8 years of profitability. A sensitivity analysis also has shown the impact of initial

    investment costs, O & M costs and electricity export rate on the IRR, NPV and equity payback. The

    initial investment cost and electricity export rate were seen with high effect on the IRR, NPV and

    equity payback. The LCOE calculated was higher than the average electricity spot price (300

    SEK/MWh) for 250 kWp and 500 kWp but lower for the other two capacities. The overall impact for

    the financial analysis was due to the decreasing of module prices, the rules that changes every year

    on electricity subsidies for renewables, tax reductions and rapid decreasing of electricity spot prices.

    In the future if the price of modules continues decreasing, spot price increases, more modification of

    the subsidy and introduction of new PV technologies integrated with other sources of energy is done

    then such projects could be more profitable.

  • 24.
    Gong, Mei
    Division of Energy Systems, Department of Mechanical Engineering, Linköping University, Linköping, Sweden.
    Exergy analysis of a pulp and paper mill2005Inngår i: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 29, nr 1, s. 79-93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Different energy and exergy concepts and methods are presented and applied to a Swedish pulp and paper mill. Flow diagrams show that the exergy content is mostly much less than the energy content of the flows. The largest exergy losses appear in the boilers. Heating processes are highly exergy inefficient. A limited Life Cycle Exergy Analysis (LCEA) shows that the exergy output amounts to over 3 times the spent exergy as non-sustainable resources. By replacing the present use of non-sustainable resources, mostly fuel oil, the mill could move towards a truly sustainable process. Copyright © 2005 John Wiley & Sons, Ltd.

  • 25.
    Gong, Mei
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Exergy and cost analysis of heating systems with energy storage2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    About three quarters of the total final energy consumption is in the form of electricity and district heat and 49 TWh of district heat was used in Sweden in 2015. The energy supply and user demands vary and do not always match. The electricity production depends on the available energy resource that often is renewable, such as wind, solar and hydro power. The heat demand strongly depends on outdoor temperature and the weather conditions. Electricity and thermal storages are needed in order to reduce the losses from the lack of match between production and consumption. The cost of energy examined by others shows that electricity storage is about 100 times more expensive than thermal storage. However, in this study cost of exergy is only 20 times more for electricity than thermal. This study views electricity and district heat from source to end use and analyze the cost of exergy with storage. With a surplus of electricity the most efficient and cheapest way is to use electricity storage, such as battery or hydro storage on the purpose of electricity usage. The advantage of thermal storage depends strongly on the purpose of use, e.g. if it is for heating purposes. Heat pump is a method to convert electricity to district heat with 56% exergy efficiency. This paper will analyze different cases in order to give a more detailed discussion. Further studies of more cases are needed in the future.

  • 26.
    Gong, Mei
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    An assessment of district heating research in China2015Inngår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 84, s. 97-105Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The recent growth of the Chinese district heating sector has been very high. No other country in the world can show the same growth rate during the last decades. The heated building area increased six times between 1995 and 2008. China has also enjoyed strong growth of scientific articles and papers about district heating in recent years. One third of all international scientific journal articles and conference papers about district heating came from Chinese scientists during 2010–2012, while Swedish scientists accounted for one quarter according to the Scopus scientific search engine. It is important to identify the Chinese district heating research to judge the potential for future collaborative research on district heating systems between Sweden/Europe and China. The 205 international publications on district heating by Chinese scientists published until 2013 have been mapped and summarised with respect to demand, supply, technology, market and environment. More diversified heat supply with renewable source was grasping the Chinese interest, since many new systems have been established, having more degrees of freedom when choosing various heat supply and technology options. The Chinese district heating systems were compared with sustainable district heating solutions in Sweden. Both countries would benefit from future research cooperation. © 2015 Elsevier Ltd.

  • 27.
    Gong, Mei
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Exergy analysis of network temperature levels in Swedish and Danish district heating systems2015Inngår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 84, s. 106-113Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Exergy concept is applied on district heating systems with different network temperature levels in their distribution networks. These district heating systems use a combination of renewables and heat recovery from other primary processes. The aim is to show simplicity and value of using exergy concept when comparing current and future temperature levels. Both the traditional exergy factor and the novel exergy utilisation rate are used in these analyses. Exergy utilisation rate expresses the ratio between the exergy delivered to customer heating systems and the exergy content in heat supply input to the distribution network. The analyses are performed on four different generations of district heating technologies, two national groups of district heating systems in Denmark and Sweden for revealing variations among systems, and two municipal systems for revealing variations within systems. The main conclusions are simplifications can be introduced in order to analyse the network temperature levels, current exergy factors reveal that current temperature levels can be reduced, and that almost two thirds of the exergy content in heat supply input are lost in the heat distribution chain. These conclusion will be vital input in developing the future fourth generation of district heating systems using both renewables and heat recovery. © 2015 Elsevier Ltd.

  • 28.
    Gong, Mei
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Mapping energy and exergy flows of district heating in Sweden2017Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 116, s. 119-127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    District heating has been available in Sweden since the 1950s and used more than half of the total energy use in dwelling and no-residential premises in 2013. Energy and exergy efficient conversion and energy resources are key factors to reduce the environmental impact. It is important to understand energy and exergy flows from both the supply and demand sides. The exergy method is also a useful tool for exploring the goal of more efficient energy-resource use. Sankey diagrams together with energy and exergy analyses are presented to help policy/decision makers and others to better understand energy and exergy flows from primary energy resource to end use. The results show the most efficient heating method in current district heating systems, and the use of renewable energy resources in Sweden. It is exergy inefficient to use fossil fuels to generate low quality heat. However, renewable energies, such as geothermal and solar heating with relative low quality, make it more exergy efficient. Currently, about 90% of the energy sources in the Swedish district heating sector have an origin from non-fossil fuels. Combined heat and power is an efficient simultaneous generator of electricity and heat as well as heat pump with considering electricity production. Higher temperature distribution networks give more distribution losses, especially in exergy content. An outlook for future efficient district heating systems is also presented.

  • 29.
    Gong, Mei
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energiteknik.
    Mapping Energy and Exergy Flows of District Heating in Sweden2016Inngår i: Proceedings the 15th International Symposium on District Heating and Cooling: September 4th - 7th, 2016, Seoul, South Korea / [ed] Rolf Ulseth & Kyung Min Kim, 2016, s. 96-102Konferansepaper (Fagfellevurdert)
    Abstract [en]

    District heating has been available in Sweden since the 1950s and used more than half of the total energy use in dwelling and no-residential premises in 2013. Energy and exergy efficient conversion and energy resources are key factors to reduce the environmental impact. It is important to understand energy and exergy flows from both the supply and demand sides. The exergy method is also a useful tool for exploring the goal of more efficient energy-resource use. Sankey diagrams together with energy and exergy analyses are presented to help policy/decision makers and others to better understand energy and exergy flows from primary energy resource to end use. The results show the most efficient heating method in current district heating systems, and the use of renewable energy resources in Sweden. It is exergy inefficient to use fossil fuels to generate low quality heat. However, renewable energies, such as geothermal and solar heating with relative low quality, make it more exergy efficient. Currently, about 90% of the energy sources in the Swedish district heating sector have an origin from non-fossil fuels. Combined heat and power is an efficient simultaneous generator of electricity and heat as well as heat pump with considering electricity production. Higher temperature distribution networks give more distribution losses, especially in exergy content. An outlook for future efficient district heating systems is also presented.

  • 30.
    Idris, Lina
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap. Swedish institute.
    Road map of the ultimate sustainable bio-fuel production from microalgae2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 31.
    Ingemarsson, Sebastian
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Pettersson, Per-Johan
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Economizer i bostadsvärmepumpar2012Independent thesis Basic level (degree of Bachelor), 15 poäng / 22,5 hpOppgave
    Abstract [sv]

    I takt med stigande energipriser finner fler och fler det lönsamt att installera värmepump för att reducera sitt energibehov. Värmepumpar har dock svårigheter att tillgodose värmebehovet när utomhustemperaturen sjunker under -10°C. Detta problem kan minskas med så kallade economizerkopplingar, denna rapport jämför de båda economizersystemen flash tank cycle (FTC) och internal heat exchanger cycle (IHXC). Eftersom det har visat sig att vinsterna med economizerkopplingar är som störst då temperaturlyftet är stort är det mest intressant att jämföra dem i luft/vatten värmepumpar. Detta på grund av att övriga applikationer som berg-, jord- eller luft/luft-värmepumpar inte utsätts för samma stora temperaturvariation då utetemperaturen faller. Därför avgränsades rapporten till att endast omfatta economizerkopplingar i luft/vatten värmepumpar. Syftet i rapporten har växt fram ur den strävan som finns i att ständigt energieffektivisera vår bostadssektor vad det gäller uppvärmning, där värmepumpar idag har en viktig roll. Bakgrunden i rapporten är relativt omfattande för att ge läsaren den nödvändiga informationen för att sätta sig in i resultatet. Bakgrunden, eller den allmänna tekniska beskrivningen, innehåller bland annat övergripande beskrivningar beträffande de vanliga komponenterna i en värmepump, definition på en economizer samt vilka möjligheter economizern ger. Metoden för arbetet bestod i en litteraturgranskning där jämförelser som lett fram till resultatet togs ur artiklar från andra experimentella försök inom området. Nyckeltal som jämfördes var COP (Coefficient Of Performance), elanvändning, kyleffekt och värmeeffekt vid låga förångningstemperaturer. Resultaten pekade på att FTC-systemet har en fördel jämtemot IHXC vid kallare klimat på grund av sin bättre värmeeffekt och högre COP. Däremot drogs slutsatsen att IHXC har fördelar som noggrann reglerkapacitet och större tolerans vid val av köldmedie eftersom ingen fasseparation med tillkommande problem sker i denna koppling. När värmepumpsprocessen vänds och används till kylning kommer rapporten fram till att skillnaden mellan de två systemen är försumbar.

  • 32.
    Jalaei, Fatemeh
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS).
    Application of a mathematical approach in modeling wind time series: A general survey of the Langevin method2015Independent thesis Advanced level (degree of Master (One Year)), 40 poäng / 60 hpOppgave
    Abstract [en]

    Today, the great importance and benefits of renewable energies as a source of endless energy is obvious for all.

    Wind is recognized as one of the most stable and safest type of energy, due to ease of access as well as applying modern technical and scientific methods in order to its extraction.

    In this regard, much effort has been done in the developed societies to obtain knowledge besides getting access to new techniques in the exploitation of this unlimited wealth.

    Apart from the new aspects of the proposed research in wind area, the extraction operation requires specialists to advanced techniques and scientific research.

    The development of societies and their increasing necessity to energy resources have increased the importance of safe and clean renewable energy.

    This study investigates a technique to specify the power performance of the wind turbine directly from measured data which fluctuate with high frequency. This project is a review of a dynamical method for the specification of wind turbines' power curves.

    Considering the power output of a wind turbine in this study, the basic concept is to divide its dynamics into two components; a deterministic(relaxation) and a stochastic(noise) functions which are equivalent to the wind turbines' real behavior itself and the exterior wind turbulence.

    It specifically presents a procedure to estimate the reaction of the wind turbine as a machine to the wind speed dynamically.

    In this method, reconstruction of the coefficients from the measured data and extraction of the specification of the power output have been done. The main focus of this technique is on differential equations which are recognized as Langevin equations.

    As the consequence, it is shown; with this method we will be able to percept the conversion dynamics of wind turbines and get the power curves' results with high precision. The results demonstrate that power performance's specification is accurately reconstructed from the measured data by the quick estimation of the coefficients from data.

    Furthermore, the high accuracy and fast estimation of the power curves would be considered as preferences in this method.

  • 33.
    Jensen, Henrik
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Solcellsanläggningars kostnadseffektivitet för elkrävande verksamhet: Lönsamhet, miljöavtryck och självförsörjningsgrad för solcellssystem med olika orientering2016Independent thesis Basic level (degree of Bachelor), 180 hpOppgave
    Abstract [en]

    The primary aim of this thesis was to use the calculation instrument for the solar energy potential map of Landskrona to simulate several PV systems to a sanitation company. The calculation tool is designed to calculate the profitability and environmental benefits of installing solar panels. The calculation tool was adapted in order to compare cost efficiency, environmental benefit and degree of self-sufficiency and self- consumption for the solutions. The PV system was planned to a company, Landskrona Svalöv Renhållning (LSR).

    Furthermore, four different ways to construct the PV system were investigated; flat against the roof, tilted with respect to the roof, tilted with respect to the roof and oriented (azimuth angle), as well as an installation with a string of tilted PV modules together with PV modules mounted flat against the roof. Variation of the system configurations was achieved by changing the parameters tilt and azimuth angle. The capacity was adjusted so that the annual production would be 83 500 kWh for all the studied systems. The different systems were optimized in two ways; first for the most output per module, and secondly for the greatest self-sufficiency in order to minimize the losses of excess production.

    PV modules optimally oriented for production per module provides the highest profitability and lowest payback period. The study suggests that photovoltaic systems are a competitive installation for LSR even without subsidies.

    The degree of self-consumption was 11 %. Simulation results showed that the degree of self-sufficiency could only be increased marginally by simply changing the orientation of solar cells (with power adapted to maintained production level). There was no significant benefit from tilting the solar cells by 90 ° to increase self-sufficiency in the winter.

    The simulations showed that almost all of the produced electricity was used to LSR 's internal load. This high degree of self-consumption showed very little excess electricity was produced. LSR is connected to the medium voltage power grid via two transformers. The surplus production covered only part of the no-load losses in transformers. Surplus electricity could therefore not be sold, but the high self-consumption rate limited this loss of revenue.

    The solar electricity from crystalline silicon cells, results in slightly higher greenhouse gas emissions than wind power but much lower than the production mix of electricity available in the market. The self-produced solar electricity contributed to the environment because LSR did not have to buy the contracted wind electricity, which then became available for others.

    The study's conclusions are that a PV system is likely to be profitable for LSR. Self-sufficiency would be about 11%, and the self-consumption rate of 98%. The environmental benefit consisted of the contribution of renewable energy in the mix of electricity generation on the market.

  • 34.
    Jönsson, Linnea
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Sänkt returtemperatur: Potentiell besparing i fjärrvärmesystem2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Optimizing energy systems is, in Sweden, as in many other countries, of growing interest. District heating systems are no exception. In 2012, 285 out of 290 municipals in Sweden had district heating in use and the majority of these systems have a higher return temperature than that which is possible with an error-free substation of day current technology. To, when possible, lower the return temperature is a way of increasing the effectiveness of the district heating system.This study means to investigate, through simulations and calculations, how big of a reduction in production cost a lower temperature in the city of Ystad’s district heating system would correspond to. The results show that a cold year, such as 2010, 1.8 SEK of the production cost could be saved per MWh sold heat for a whole year and 1°C temperature lowering. Equivalent value for a warm year such as 2011 was concluded to be 1.2 SEK/MWh,°C.

  • 35.
    Jönsson, Linnea
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Thermal energy storage systems in an energy company's district heating system: Exploring ways of handling daily and seasonal heat load variations in Höganäs2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 36.
    Kalén, Jonas
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Åkerlund, Nathan
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Gårdsbaserad biogas på Nya Skottorp: utvärdering och optimering av anläggningen och uppgradering av biogasen2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Biogas is an expanding sector within the broad field of agriculture and animal production. Small-scale biogas offers local combined power and heating production and the substrate is transformed into high-quality biological fertilizer. This bachelor thesis focuses on a pig farm in south-western Sweden, where biogas is produced from pig manure, evaluates and suggests ways of optimizing the process and investigates whether investing in an upgrading plant would be a feasible and more cost-efficient option. The results show that the biogas plant is working well, although the production differs from the original plans. This shows in turn that planning and examining the basic conditions before making the investment is of great importance, as well as monitoring and keeping detailed statistics of the running process. Logistical factors make optimizing the process through additional substrates difficult. The thesis shows that investing in a Biosling upgrading plant would be a profitable option, supposing that the upgraded gas is sold via the natural gas infrastructure. Furthermore, many farmers are interested in producing their own fuel for tractors and other machines, which offers more future alternatives for the upgraded biogas. However, biogas producers in Sweden today are not offered any particular subsidies, which makes it especially hard for small-scale producers.

  • 37. Kjellander, Matilda
    et al.
    Tengvall, Anders
    Design of a small scale hybrid photovoltaic and wind energy system2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Approaching problems with global warming due to the use of fossil fuels, means that new system solutions have to be investigated. This report investigates the possibility to expand an existing photovoltaic system with a wind turbine generator to simplify the expansion of renewable energy sources. Through an extensive literature study and simulation in SIMULINK the result has been developed and tested. It shows that it is possible to connect a wind turbine generator to the same inverter as the PV-modules if no MPPT algorithm for the PV-modules is integrated. To protect the inverter a dump load has to be connected. Because of the complexity a DC-coupled system brings, AC-coupling is advised when expanding PV-modules with a WTG. The optimal wind turbine is considered to be a permanent magnet synchronous generator connected to the AC-bus through a full-effect inverter. The turbine should be chosen according to the intended location based on wind conditions and desired energy production.

  • 38.
    kollappillai Murugan, Sai Varun
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Analysis of Hybrid Offshore Floating Wind and Marine Power2018Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Wind energy is a major part of renewable energy production. With fossil fuel depletion and climate change at the cusp, it is an absolute need to implement or evolve the current source or utilization of renewable energy. The wind has been dominating the onshore for many decades and offshore wind turbines are available at shallow depths.  To extract more wind energy source deep sea location is recommended. Also, in deep seas, ocean current energy is utilized very sparsely compared to the dominating wind and solar energy. So far no hybrid offshore horizontal axis and ocean current system are in existence.

    Based on the depth of the sea water the offshore floating structure is classified. Usually, for any floating structure stability is an apprehension. In an offshore floating structure, the damping with respect to the thrust force exerted on the wind turbine will affect the life of the wind turbine. During high wind speed, the angle of inclination would go up to about 4 degrees. The time required for the floating structure to come to rest may also be high. We present an analysis based on an existing floating structure which is a ballast stabilized the floating structure. In this paper, we add an additional submerged turbine and do a 2D analysis on the floating structure to find out whether the structure’s oscillation is well damped or not. We also discuss whether the weight of the submerged will influence the stability or by changing the radius of blades of the submerged turbine will affect the damping.

  • 39.
    Kronebrant, Mattias
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Cost comparison of solar home systems and PV micro-grid: The influence of inter-class diversity2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Nearly one fifth of the global population lacks access to electricity and electricity access is essential for economic growth and human well-being. SHSs and micro-grids both have the possibility of increasing the electricity access in developing countries. The decision to choose either SHSs or micro-grids for rural electrification is a complex task that must consider both the technological factors that separate these two systems and the non-technological factors. Separate times of peak load between households (inter-class diversity) has shown to be one major advantage for the use of micro-grids. Studies have shown that the diversity factor present in micro-grids can scale down the necessary capacity of PV modules and energy storage of up to 80%, in comparison to stand-alone systems (e.g. SHSs). These reductions are nevertheless based on assumed diversity factors, not using real load profiles and the necessary capacities are calculated using intuitive methods (known to be inexact).

    From interviews in a rural community of Nicaragua, the author generated load profiles and determined the diversity factor of the community. The load profiles were generated with a specially designed software to formulate realistic load profiles for off-grid consumers in rural areas. These load profiles were later used in the software HOMER where the diversity’s influence on required capacity and NPC were determined by comparing SHSs to a PV based micro-grid. The study showed that the required capacity and NPC of the inverter and charge controller are clearly decreased as an influence of inter-class diversity. The required PV and battery capacity are also decreased when a micro-grid is utilized, but these reductions are most likely a result from the limited nominal power per component considered in HOMER.

  • 40.
    Landqvist, Anton
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Eklund, Gustav
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Analys av en spänningshöjning på ett mellanspänningsnät2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Denna rapport analyserar följderna av en spänningshöjning i ett mellanspänningsnät från 6 kV till12 kV alternativt till 20 kV. Rapporten undersöker ett befintligt elnät i södra Sverige som ägs avMellersta Skånes Kraft ek. För. (MSK). Det består av 177 stycken transformatorer, har ca 2500kunder och överförde totalt runt 32 GWh år 2016.Rapporten är uppdelad i tre delar, den första delen behandlar de tekniska aspekterna av en förhöjdspänningsnivå, den andra delen behandlar de ekonomiska följderna detta kan medföra och dentredje delen presenterar slutsats och diskussion.Elnätet simulerades i programvaran Neplan och elektriska beräkningar utfördes på olika driftfallunder årets månader. Lasterna i nätet fastställdes bland annat genom att använda Velandersmetod. Information och indata av nätets komponenter inhämtades genom produktblad, kontaktmed tillverkare och MSK samt genom diverse litteratur.Rapporten visar att en ökad spänningsnivå i elnätet minskade transmissionsförlusterna ochmedförde lägre kostnader för elnätföretaget. Det medförde också andra tekniska fördelar,exempelvis att spänningsfallet minskade, belastningsgraden av nätets komponenter minskade samtatt kortslutningsströmmen blev lägre. En högre spänningsnivå ökade nätets generering av reaktiveffekt.Elnätföretagets intäktsram förändras vid en förhöjd spänningsnivå, dels till följd av det tillägg somerhålls vid effektivt utnyttjande av elnät, dels då vissa anläggningsdelar i nätet ersätts. Lönsamheteni att investera inför en ökad spänningsnivå berodde på flera faktorer, bland annat vilka typer avanläggningsdelar som behövde ersättas, kapitalstrukturen på investeringen och elnätföretagetskalkylränta. I lönsamhetsanalysen använder rapporten internräntemetoden.I fallet för MSK antogs samtliga av elnätets transformatorer behöva ersättas vid en ökadspänningsnivå, vilket således ökade intäktsramen inför nästa tillsynsperiod med totalt ca 3,4 Mkr.Internräntan för investeringen bestämdes till 4,62%. En viss osäkerhet råder dock kring ett antalav elnätets olika anläggningsdelar (kablar, ledningar och transformatorer) vilket kan påverkainvesterings omfattning, utfall och om nätet kan hantera en förhöjd spänningsnivå i sitt nuvarandeskick.

  • 41.
    Larsson, André
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Hild-Walett, Dennis
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    SOLPANELERS MÖJLIGHETER, EN AKTUELL RAPPORT FÖR MONTAGE PÅ FASTIGHETEN KORNHILL2012Independent thesis Basic level (degree of Bachelor), 15 poäng / 22,5 hpOppgave
    Abstract [en]

    This thesis deals with the possibilities of installing solar panels on a property, the building is owned by Kornhillschurch and called Kornhill. The owners of the property wanted to learn more about potentials for installation of solar panels on the property, therefore we described different types of solar cells and solar cells essential function to generate electricity in the report. Different factors that are limiting the generated energy are mentioned.

    An investigation of the property’s potential has been made in order to consider different designs. When sites that were considered suitable for solar cells were selected, different design options were made, one for each site. Then a number of financial calculations on the dimensioned plants were made to see if each plant will be profitable.

  • 42.
    Larsson, Martin
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Sarner, Viggo
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Hylte carport: Carporten som laddar bilen2017Independent thesis Basic level (degree of Bachelor), 180 hpOppgave
    Abstract [en]

    This study analyses a carport located in the Hylte municipality equipped with eight EV charging stations that use solar panels as its only roof material. The main focus of the report is to review the maximizing of internal electricity consumption, implementation of load management, effects on the local grid and to report general improvements. Data was collected from driving logs, analysis of charging patterns and the inverter. The data was then compiled with the software Polysun and MS Excel for further investigation of internal electricity consumption, load management, electricity quality and more. The report shows that there is a 29.1 % internal energy consumption and that implementation of a 100 kWh battery may raise it to as much as 57.4 %. It also shows that there is a possibility of saving up to 39 238 SEK per year with the implementation of load management and that a 19 % increase of electricity production would be possible if the construction had the optimized direction and roof angle.

  • 43.
    Larsson, Sebastian
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Bulleremissioner från vertikalaxlade vindkraftverk2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Wind power in Sweden is expanding in response to the government's decision that 49% of Sweden's power should originate from renewable energy sources by the year 2020. Problems with noise and sound emissions related to wind turbines are a constant argument against the wind power expansion and this paper means to examine if vertical axis wind turbines might be a viable alternative to the conventional horizontal design for noise sensitive areas. In order to determine factors like difference in frequency, noise propagation and noise emission level, measurements of both horizontal and vertical axis wind turbines have been completed and the data analyzed with MATLAB. It is shown that there is a difference in how the noise from the two types of turbines propagates due to avariation in the frequency spectra of the emitted sound. It is also shown that vertical axis wind turbines generate a lower sound emission with less intensity inthe lower frequencies.

  • 44.
    Larsson, Sebastian
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Wind turbines - a study on the correlation between rotor size and noise characteristics2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Wind power is a massively increasing energy source in the European Union, due to the 2020 goals that 20% of EU:s energy flow has to originate from renewable sources. Big wind turbines produce low frequency noise, which is a growing problem as the rapid technical development leads to larger and larger turbine.

    This master thesis aims to examine the frequency distribution of the noise emitted from wind turbines of different sizes with the ultimate goal to establish trends. Using sound recordings from Vestas V27, V42 and V90 turbines, the noise is divided into octave bands using MATLAB to study the amount of low frequency noise. Due to a lack of accessibility to turbine sites, some site observed in the study suffer from a large amount of nearby noise pollution. However, a change in sound level in the region of the 63 to 250 Hz one-third octave bands is shown when comparing the V90 turbine data to the smaller sizes, correlating well with previous research in the field, but more research and measurements are needed to explain the occurrence on a more detailed level.

  • 45.
    Lidvall, Martin
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Sjögren, Jonas
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Solmodul jord- och bergvärmepump2012Independent thesis Basic level (university diploma), 15 poäng / 22,5 hpOppgave
    Abstract [sv]

    An increasing number of heat pump producers have developed heat pumps that can be connected to solar panels. In this thesis we have examined the possibilities of connecting solar panels to existing ground source- and geothermal heat pumps that has not been adapted to solar panels. During the work process, a prototype plant has been built to compare our theory with the practical results and with our designed sizing tool. The work has rendered in knowledge that will be used to build a sun module that can be easily connect to the existing heat pump system. The existing heat pump, our test plant, has been supplemented by an advanced storage tank used to allow different operating modes. When there is an excess of solar energy from the solar collectors the borehole should be recharged and be stored in the ground for a shorter period of time. The heat pump refrigerants should also be preheated in the storage tank where the heat from solar collectors is not sufficient to directly go to the heating or domestic hot water demand. These functions should make it possible to maximize the usage of the solar power in the system. The thesis has rendered in a design basis for our client, on how a solar module best should be connected to the existing heat pump system. The conclusion is that there are difficulties in profitability and return on the investment cost of a sun module, because the pay-off time becomes unreasonably long. Several features such as preheating the brine circuit are not economically justifiable when the investment cost is too high in relation to the energy gain. The benefits are increased efficiency at both the solar collectors and the heat pump, along with the potential for a longer life for the heat pump.

  • 46.
    Lorenzo Guevara, Emiliano Gabriel
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Design of an Off-grid PV System for Households in Perú and Sweden2017Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Because of global warming and the Paris agreement from 2015, countries need to switch their energy sources into clean sources. For some countries, like Perú, electricity produced from renewable energy sources is still a new technology. Its electricity demand depends entirely on traditional hydropower and thermal plants. Despite the high solar radiation in the coast and Andes (mountain range that passes through the entire South American continent), solar electricity is not developed and it fairly reaches the 1% of the national electricity production. Sweden, similarly, also produces its highest share on electricity from hydropower. However, nuclear energy and renewables like biomass and wind cover the rest of the demand, compared to thermal plants for Perú.

    On the other hand, most of the poor citizens of Perú live in the Andes, especially in remote villages, disconnected from the national grid and suffering from the cold during winter. Because their energy demand is low, it is not profitable for the electrical companies to give them electricity. The Swedish population, however, has 100% access to electricity. Despite that, high prices on maintaining the connection to the electricity network, and constant failures because of bad weather (more common nowadays because of global warming), brings the idea to disconnect from the grid and produce one´s own electricity, with, for example, photovoltaic systems. These problems occur not exclusively in Sweden.

    The work done on this thesis consists on a design of an off-grid solar PV system using batteries for energy storage, both for a remote farmer village in the high Andes in Perú (Ungalluta 2) and for a rural, low populated village in the center of Sweden (Gåsborn). The design is done manually and by software (PVSyst), with real life components, analyzing costs and the possibility to live entirely on solar power. The priority when choosing the components is the lowest price.

    For Ungalluta 2, with a demand of 17.1kWh/d (11 people), 13 PV modules and 1600Ah of battery capacity (Lead Acid) are needed, with a payback in approximately 40 years, renewing the PV panels on year 25 because of degradation. The initial investment is 21540EUR.

    For Gåsborn, with a demand of 36.44kWh/d (average Swedish family with children), 42 PV modules and 2850Ah of battery capacity (Lithium) are needed, with a negative payback, even increasing the PV modules to cover the entire year (more than 400). This is because the solar irradiation is quite low during winter and the load demand needs to be satisfied with considerable amounts of Diesel with a backup generator.

    After analyzing the results, it is possible and viable to build PV systems for the villagers in the Andes of Perú, but they will need monetary help of the government (high initial cost). For Sweden, it is not profitable to depend entirely on PV power. Other renewable sources must complement it, such as wind, to compensate the low solar irradiation and reduce the diesel consumption.

  • 47.
    Lund, Rasmus
    et al.
    Department of Development and Planning, Aalborg University, Copenhagen, Denmark.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Mapping of potential heat sources for heat pumps for district heating in Denmark2016Inngår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 110, s. 129-138Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ambitious policy in Denmark on having a 100% renewable energy supply in 2050 requires radical changes to the energy systems to avoid an extensive and unsustainable use of biomass resources. Currently, wind power is being expanded and the increasing supply of electricity is slowly pushing the CHP (combined heat and power) plants out of operation, reducing the energy efficiency of the DH (district heating) supply. Here, large heat pumps for district heating is a frequently mentioned solution as a flexible demand for electricity and an energy efficient heat producer. The idea is to make heat pump use a low temperature waste or ambient heat source, but it has so far been very unclear which heat sources are actually available for this purpose.

    In this study eight categories of heat sources are analysed for the case of Denmark and included in a detailed spatial analysis where the identified heat sources are put in relation to the district heating areas and the corresponding demands. The analysis shows that potential heat sources are present near almost all district heating areas and that sea water most likely will have to play a substantial role as a heat source in future energy systems in Denmark.

  • 48.
    Lygnerud, Kristina
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Challenges for business change in district heating2018Inngår i: Energy, Sustainability and Society, ISSN 2192-0567, Vol. 8, nr 1, artikkel-id 20Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: The Swedish district heating sector is successfully transitioning to a low-carbon energy system. The industry has expanded since the 1950s and currently meets more than half the Swedish heat demand. The heat market was deregulated in 1996, and thereafter, companies have been exposed to an increasing number of challenges related to technology, institutional factors and market. Since municipal ownership dominates, municipal companies must manage these challenges to ensure future competitiveness. However, theory suggests that business change is difficult when the current model is still working. To date, Swedish district heating companies have revisited their price models and customer perceptions. There is limited knowledge on how the business challenges are managed and on the management strategy’s impact on the business. In this paper, new knowledge is generated regarding how the customer and resource-oriented sides of the municipally owned district heating business in Sweden are changing. Methods: A case study approach was adopted. Data were collected by interviews and by review of the national research programme on district heating (Fjärrsyn). The programme served as a proxy for frontline research on Swedish district heating. The data were analyzed through the business model canvas framework. Results: Changes to meet external pressures are identified on the customer side of the business model, but changes are also spreading to other parts of it. However, the key resource component (distribution networks and production unit) and its logic of economics of scale are unchanged and dominate. The logic is not compatible with shrinking heat demand; nevertheless, it is preferred. Conclusions: It is concluded that external challenges have resulted in changes in the customer side of the business model. However, the largest challenge is the transformation of key resources. Accounting for external challenges extends the life of the current business model, but it is not increasing competitiveness. The prolonged life creates a window of opportunity for the companies to begin the needed transformation of their key resources. If the transformation is successful, district heating will have a role in the future energy system. If the transformation is not undertaken, the future is less certain. © 2018, The Author(s).

  • 49.
    Möller, Bernd
    et al.
    Europa-Universität Flensburg, Flensburg, Germany.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Updated Peta atlas for each MS with the final level of district heating recommended in WP6: Deliverable 6.52018Rapport (Annet vitenskapelig)
    Abstract [en]

    This report presents in brief the development and content of the Pan-European Thermal Atlas (Peta), with focus on the current update in response to project deliverable 6.5, which concerns for the final levels of district heating for each of the 14 member states to be recommended in WP6.

    The update refers to data that has been rendered in work package 2 (WP2) and consists of three main parameters: a high-resolution model of the heat demand and its density; the specific investment costs for district heating systems, and allocated volumes of industrial and energy sector excess heat for current and prospective district heating areas. All of these parameters represent spatially derived information that has been provided as data matrices to the energy systems modelling colleagues in WP6, as a basis for their assessment of national heating and cooling scenarios for the 14 member states (deliverable 6.4).

    In terms of dynamic maps, a new dynamic layer, labelled: Recommended DH levels, has been added to the Peta 4.2 online web map application on August 31, 2018, where it now is publicly available. This new layer contains recommendations to develop district heating at the local scale, based on current heat demand densities, temporally and spatially accessible excess heat from industries, from waste-to-energy facilities, from current power plant locations, and in terms of access to locally available renewable energy resources.

    In November 2018, the Pan-European Thermal Atlas is scheduled for a comprehensive update, rendering the third version (Peta 4.3), to be released at the 4th International Conference on Smart Energy Systems and 4th Generation District Heating conference (SES4GDH) in Aalborg, Denmark, on November 13-14. Apart from several other new dynamic layers to be introduced in this coming update (see sub-section 1.2.3), the new layer on recommended district heating levels, added here to the current Peta 4.2, will also be part of this general update.

  • 50.
    Möller, Bernd
    et al.
    Europa-Universität Flensburg, Flensburg, Germany & Aalborg University, Aalborg, Denmark.
    Wiechers, Eva
    Aalborg University, Aalborg, Denmark.
    Persson, Urban
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Grundahl, Lars
    Aalborg University, Aalborg, Denmark.
    Connolly, David
    Aalborg University, Aalborg, Denmark.
    Heat Roadmap Europe: Identifying local heat demand and supply areas with a European thermal atlas2018Inngår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 158, s. 281-292Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In 2016 the first Strategy for Heating and Cooling of the European Union has shown that district heating and cooling networks can integrate renewable energies in an increasingly energy-efficient built environment. At the same time, the heating and cooling sector is probably the most diverse and least mapped component of the European energy system. The aim of the Pan-European Thermal Atlas is to improve the knowledge base for the geographical distribution of heat and cooling demands across Europe. Demand densities of the demanded thermal services themselves, the spatial coherence of these demands, and their location relative to sources of heating greatly affect the economy of district heating schemes compared to individual solutions. The objective is therefore to develop a comprehensive model, which can be used to a) quantify heat demands by density, b) group coherent areas with demands into prospective supply zones, c) produce supply curves for these zones, and d) ultimately calculate local energy mixes on the basis of allocated excess heat as well as renewable energy sources. The developed method spatially disaggregates national demand data to high-resolution geospatial data on urban structures. The resulting atlas allows for an advanced quantitative screening process, which can establish the basis for energy systems analyses relying on geographically explicit information on the heating demand and supply volumes and costs. The present paper presents version 4 of the Pan-European Thermal Atlas, which takes another step towards higher spatial resolution and confidence in comparison to its predecessors, version 1 to 3. For the first time, a 100m resolution heat atlas of Europe is being presented, which may help describing the heating sector in the required spatial resolution. By means of spatial statistical analyses using ordinary least square linear regressions, multiple spatial inputs such as population, degree of built-up and its derivatives are turned into a coherent model of the urban tissue. Plot ratios form the basis of models of heat demand in single and multi-family residential buildings as well as the service sector. Prospective district heating areas have been delineated, and the resulting zoning of heat supply has been linked to a resource-economic analysis, which allows for cost-supply studies in disaggregated form. The present heat atlas version 4 is now available for 14 countries that altogether represent 90% of the heat demand in the 28 European Union member states. First results are being presented with emphasis on the achieved methodological improvements. Moreover, a newly developed online mapping system is being presented, which will assist in mapping the new geography of heating and cooling demands and supplies. © 2018 Elsevier Ltd. All rights reserved.

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