du.sePublications
Change search
Refine search result
12345 151 - 200 of 237
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • chicago-author-date
  • chicago-note-bibliography
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 151.
    Ochs, Fabian
    et al.
    Univeristy of Innsbruck.
    Fedrizzi, Roberto
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Dermentzis, Georgios
    Univeristy of Innsbruck.
    D6.7 Guidelines on Systemic Approach and Checklist2016Report (Other academic)
  • 152.
    Ollas, Fredrik
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Kling, Mattias
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Analys av ett mikronät vid Ihushi Development Center i Tanzania2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study covers a research about how a micro-grid have performed, and

    in this specific case at Ihushi Development Center in Tanzania.

    The Measurements that have been made, have followed a standard to be

    able to be used as a universal data for future studies or just directly be

    comparable to other micro-grids with a similar rig and conditions.

    During the study, a new model have been created to easily analyze the raw

    data and perform the necessary calculations, which also is of high value in

    coming work on this micro-grid.

    There have also been some simulations done due to the vast amount of

    errors that have been both scattered and continuously appearing, this had

    to be taken care of and the values needed have been extracted and

    estimated from other sources and methods.

    Efficiencies and performances have been calculated for different parts of

    the system and have been commented so they can in a fair way be used

    for an evaluation or a future study.

    These results have partially been compared with the previous evaluations,

    but due to missing data in the previous report, a complete comparison and

    conclusion have not been possible.

  • 153.
    Paavilainen, Janne
    Dalarna University, School of Technology and Business Studies, Energy Technology. Chalmers.
    Characterization of Chimney Flue Gas Flows: Flow Rate Measurements with Averaging Pitot Probes2016Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Performance testing methods of boilers in transient operating conditions (start, stop and combustion power modulation sequences) need the combustion rate quantified to allow for the emissions to be quantified. One way of quantifying the combustion rate of a boiler during transient operating conditions is by measuring the flue gas flow rate. The flow conditions in chimneys of single family house boilers pose a challenge however, mainly because of the low flow velocity. The main objectives of the work were to characterize the flow conditions in residential chimneys, to evaluate the use of the Pitot-static method and the averaging Pitot method, and to develop and test a calibration method for averaging Pitot probes for low 𝑅𝑅𝑅𝑅.A literature survey and a theoretical study were performed to characterize the flow conditions in in single family house boiler chimneys. The flow velocities under normal boiler operating conditions are often below the requirements for the assumptions of non-viscous fluid justifying the use of the quadratic Bernoulli equation. A non-linear calibration coefficient is required to correct for these viscous effects in order to avoid significant measurement errors. The flow type in the studied conditions changes from laminar, across the transition regime, to fully turbulent flow, resulting in significant changes of the velocity profile during transient boiler operation. Due to geometrical settings occurring in practice measurements are often done in the hydrodynamic entrance region, where the velocity profiles are neither fully developed nor symmetrical. The predicted changes in velocity profiles are also confirmed experimentally in two chimneys.Several requirements set in ISO 10780 and ISO 3966 for Pitot-static probes are either met questionably or not met at all, meaning that the methods cannot be used as such. The main issues are the low flow velocity, viscous effects, and velocity profiles that change significantly during normal boiler operation. The Pitot-static probe can be calibrated for low 𝑅𝑅𝑅𝑅, but is not reliable because of the changing velocity profiles.The pressure averaging probe is a simple remedy to overcome the problems with asymmetric and changing velocity profiles, but still keeping low the irrecoverable pressure drop caused by the probe. However, commercial averaging probes are not calibrated for the characterized chimney conditions and the information available on the performance of averaging probes at low 𝑅𝑅𝑅𝑅 is scarce. A literature survey and a theoretical study were done to develop a method for calibrating pressure averaging probes for low 𝑅𝑅𝑒 flue gas flows in residential chimneys.The experimental part consists of constructing a calibration rig, testing the performance of differential pressure transducers, and testing a prototype pressure averaging probe. The results show good correlation over a wide operation range, but the low 𝑅𝑅𝑅𝑅 characteristics of the probe could not be identified due to instability in the chosen pressure transducer, and temperature correlation for one of the probes while not for the other. The differential pressures produced are close to the performance limitations of readily available transducers and it should be possible to improve the method by focusing on finding or building a suitable pressure transducer. The performance of the averaging method can be improved further by optimizing the geometry of the probe. Another way of reducing the uncertainty would be to increase the probe size relative to the conduit diameter to produce a higher differential pressure, at the expense of increasing the irrecoverable pressure drop.

  • 154.
    Pamidi R., Sreenivaasa
    et al.
    Exergy Ltd..
    Polidori, Carlo
    Veltha IVZW.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Ghrissi, Meftah
    Robosoft SA.
    Carrel, Aubert
    Robosoft SA.
    Menta, Andrea
    CO.MET.ART. SAS.
    Ramiro, Manuel
    ADVANTIC Sistemas y Servicios.
    Kotilainen, Titta
    Valoya OY.
    Aikala, Lars
    Valoya OY.
    ZEPHYR Project – Deliverable D2.4: Technical specification for the Power system with solar panels2013Report (Other (popular science, discussion, etc.))
  • 155.
    Pamidi, Sreenivaasa R
    et al.
    Exergy Ltd..
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Reducing the impact of forest plant production - Design of a stand-alone PV-hybrid system for powering an innovative forestry incubator2014In: 29th European Photovoltaic Solar Energy Conference and Exhibition Proceedings, 2014, p. 3811-3814Conference paper (Other academic)
    Abstract [en]

    Nowadays, the high demand of forestry products imposes a high pressure on the ecosystems and can derive in biodiversity lost and other ecological problems. Planted forests can contribute to more sustainable practices and help addressing other problems of global concern such as climate change, erosion and desertification. Large scale production of seedling is required to offset the high harvesting rates; however these intensive methods often have a negative impact on the environment. Funded by the European Commission under the Seventh Framework Programme (FP7), the ZEPHYR project consortium is developing innovative and cost-friendly technologies for the pre-cultivation of forestry species. These will be integrated into a functional and transportable system for pre-cultivation of seedlings, with zeroimpact on the environment and not affected by outdoor conditions. To achieve this, the incubator will be powered mainly by solar energy. This work aims to present the efforts made to design and optimize the solar photovoltaic (PV) system which will be mounted on the roof of the unit. Especially developed devices such as LED growth lamps and wireless sensors will be used to reduce energy consumption and monitor the cultivation process. A load profile study was conducted and the growth protocols were adapted to perform most of the tasks during daytime to use the energy from the PV panels directly. A battery bank will be designed to provide at least one day of autonomy in central European latitudes. Moreover, the power system will also be capable of connecting to the electricity grid or use a diesel generator as a backup.

  • 156. Pan, S.
    et al.
    Wang, H.
    Pei, F.
    Yang, L.
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    An investigation on energy consumption of air conditioning system in Beijing subway stations2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, p. 2568-2573Article in journal (Refereed)
    Abstract [en]

    This paper initially depicted on the energy consumption of air conditioning systems in Beijing subway stations. An investigation was conducted among ten underground subway stations to the examination of practical operation conditions of their cooling units. The overall field testing included information such as air conditioning system formation, equipment types, system operation parameters, energy consumption and system operation efficiency. The results showed that the COP value of refrigerators in the tested subway stations were generally high at about 4.4 in average. Nevertheless, the mean EER and SCOP values were nearly 27% and 48% lower than the average COP value due to the large amount of energy consumption in water pumps, cooling towers and fans. There was a big difference among each station in terms of the instantaneous power consumption of air conditioning systems. The most energy consuming station was nearly seven times higher than the least one. It was observed that there was a lack of maintenance and system operation strategy for these underground air condition systems. A promising potential for energy saving was found out within the air conditioning systems in Beijing subway stations.

  • 157. Pan, S
    et al.
    Xiong, Y
    Han, Y
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Xia, L
    Wei, S
    Wu, J
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    A study on influential factors of occupant window-opening behavior in an office building in China2018In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 133, p. 41-50Article in journal (Refereed)
    Abstract [en]

    Occupants often perform many types of behavior in buildings to adjust the indoor thermal environment. In these types, opening/closing the windows, often regarded as window-opening behavior, is more commonly observed because of its convenience. It not only improves indoor air quality to satisfy occupants' requirement for indoor thermal comfort but also influences building energy consumption. To learn more about potential factors having effects on occupants' window-opening behavior, a field study was carried out in an office building within a university in Beijing. Window state (open/closed) for a total of 5 windows in 5 offices on the second floor in 285 days (9.5 months) were recorded daily. Potential factors, categorized as environmental and non-environmental ones, were subsequently identified with their impact on window-opening behavior through logistic regression and Pearson correlation approaches. The analytical results show that occupants' window-opening behavior is more strongly correlated to environmental factors, such as indoor and outdoor air temperatures, wind speed, relative humidity, outdoor FM2.5 concentrations, solar radiation, sunshine hours, in which air temperatures dominate the influence. While the non-environmental factors, i.e. seasonal change, time of day and personal preference, also affects the patterns of window-opening probability. This paper provides solid field data on occupant window opening behavior in China, with high resolutions and demonstrates the way in analyzing and predicting the probability of window-opening behavior. Its discussion into the potential impact factors shall be useful for further investigation of the relationship between building energy consumption and window-opening behavior.

  • 158. Pan, Song
    et al.
    Du, Saisai
    Wang, Xinru
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Xia, Liang
    Liu, Jiaping
    Pei, Fei
    Wei, Yixuan
    Analysis and interpretation of the particulate matter (PM10 and PM2.5) concentrations at the subway stations in Beijing, China2019In: Sustainable cities and society, ISSN 2210-6707, Vol. 45, p. 366-377Article in journal (Refereed)
    Abstract [en]

    The particulate matters (PM10 and PM2.5) inside urban subway stations greatly influence indoor air quality and passenger comfort. This study aims to analyze and interpret the concentrations of PM10 and PM2.5, measured in several subway stations from October 9th to 22nd, 2016 in Beijing, China. The overall methodology was based on the Statistical Package for Social Science (SPSS) software while General linear model (GLM) and correlation analysis were further applied to examine the sensitivities of different variables to the particle concentrations. The data analysis showed the average overall mass ratio of PM concentrations inside subway station is about 68.7%, much lower than outdoor condition (79.6%). In the areas of the station hall and platform, the real-time PM10 and PM2.5 concentrations varied periodically. In working and operation offices, all rooms had much higher PM concentrations than the outdoor environment when its pollution level was level 3, in which the facility room reached the highest level, while the closed meeting room had the lowest. Correlation analysis results indicated that PM10 and PM2.5 concentrations were mutually correlated (average R2 = 0.854), and a strong linear correlation (R2 = 0.897) of the subway-station PM concentrations to the outdoor PM conditions, regardless of the outdoor atmospheric PM concentrations pollution level was. Nevertheless, the impact of passenger number and temperature & humidity on the station PM concentrations was less, when compared to the outdoor environment. This paper is expected to provide useful information for further research and design of effective prevention measures on PM in local subway stations, towards a more sustainable and healthier built environment in the city underground. 

  • 159. Pan, Song
    et al.
    Pei, Fei
    Wang, Hongwei
    Liu, Jiaping
    Wei, Yixuan
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Li, Guoqing
    Gu, Yaxiu
    Design and experimental study of a novel air conditioning system using evaporative condenser at a subway station in Beijing, China2018In: Sustainable cities and society, ISSN 2210-6707, Vol. 43, p. 550-562Article in journal (Refereed)
    Abstract [en]

    Air conditioning system (AC) contributes significantly to the energy consumption of underground metros. In China, most metro stations are designed with water-cooling centralized air conditioning (WC-AC) system, it has been found that several serious problems are brought by this conventional system, such as large space occupying, water leaking, cooling tower noise and low system efficiency. In order to solve these problems, a novel energy-efficient AC system incorporating an independent evaporative condenser (EC) has been proposed and installed at Futong metro station in Beijing, China. A series of pilot measurements were conducted to analyze the cooling performance and energy consumption of this novel EC-AC system. During the testing period, the average refrigeration efficiency of COP, SCOP and ACOP in A and B side is up to 3.8/3.9, 3.4/3.4 and 2.5/2.3. At the same time, some operation problems such as unbalanced working condition have been identified during measurement. The research indicates that such EC-AC system could be a feasible solution to enhance the energy efficiency and reduce the operational costs and carbon emission in metro stations.

  • 160. Pan, Song
    et al.
    Wang, Xinru
    Wei, Yixuan
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Gál, Csilla V
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Rend, Guangying
    Yan, Da
    Yong, Shi
    Wu, Jinshun
    Liu, Jiaping
    Cluster analysis for occupant-behavior based electricity load patterns in buildings: a case study in Shanghai residences2017In: Building Simulation, ISSN 1996-3599, E-ISSN 1996-8744, Vol. 10, no 6, p. 889-898Article in journal (Refereed)
    Abstract [en]

    In building performance simulation, occupant behavior contributes to large uncertainties, which often lead to considerable discrepancies between actual energy consumption and simulation results. This paper aims to extract occupant-behavior related electricity load patterns using classical K-means clustering approach at the initial investigation stage. Smart-metering data from a case study in Shanghai, China, was used for the load pattern analysis. The electricity load patterns of occupants were examined on a daily/weekly/seasonal basis. According to their load patterns, occupants were categorized as (a) white-collar workers, (b) poor or older families and (c) rich or young families. The daily patterns indicated that electricity use was much more random and fluctuated over a wide range. Most households of the monitored communities consumed relatively-low electricity; the characteristic double peak with higher level of consumption in the morning and evening were only apparent in a relatively small subset of residents (mostly white-collar workers). The weekly analysis found that significant load shifting towards weekend days occurred in the poor or old family group. The electricity saving potential was greatest in the white-collar workers and the rich or young family groups. This study concludes with recommendations to stakeholders utilizing our load profiling results. The research provides a rare insight into the electricity-use-related occupant behaviors of Shanghai residents through the case study of two communities. The findings of the study are also presented in a meaningful way so that they can directly aid the decision-making of governments and other stakeholders interested in energy efficiency. The research results are also relevant to the building energy simulation community as they are derived from observations, and thus can have the potential to improve the efficiency and accuracy of numerical simulation results.

  • 161.
    Pande, Sohum
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Bhaladhare, Raj
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Different Photovoltaic Penetration Rates for the Planned Area of Jakobsgardarna in Borlange, Sweden2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The municipality of Borlange is planning to build a new modern, social and an ecologically sustainable district due to an increase in the city’s population. Over 1200 homes shall be built for people from all sections of the society. Due to such high levels of migration into the city, it is of utmost importance for the society to ensure that all the new constructions would be energy efficient and focused towards the goal of creating a sustainable society. The main objective of this study is to understand the importance of planning for Photovoltaics (PV) in new areas and performing a series of simulations for different scenarios with varying degrees of PV penetration for the planned residential area of Jakobsgardarna in Borlänge, Sweden.

     

    This was achieved by determining the load profiles for all buildings by thorough investigation over the previous works in the analysis of household demand loads and calculating the available roof area in several orientations with the help of model maps drawn to scale. Due to varied types of roofs and their structures, it was assumed that all buildings have a similar roof structure i.e. tilted roofs having a tilt of 30°. Batch simulation was performed in PVSyst for a base case scenario which provides the reference point for determining the total PV power and the total PV output in all orientations.

     

    The PV penetration is measured in terms of energy by dividing the total PV output with the annual demand load. Various scenarios of PV penetration are created based on the available roof areas at particular roof orientations. It can be observed that the level of PV penetration is highly dependent on the orientation of roofs. A 17% of PV penetration is observed when PV is installed only on South-facing roofs while the PV penetration reduces drastically to 9% when PV is installed only on East-West facing roofs even though there isn’t a linear reduction in the available roof area.

     

  • 162.
    Perers, Bengt
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Anderssen, E.
    Nordman, R.
    Kovacs, P.
    A simplified heat pump model for use in solar plus heat pump system simulation studies2012In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 30, p. 664-667Article in journal (Refereed)
    Abstract [en]

    Solar plus heat pump systems are often very complex in design, with sometimes special heat pump arrangements and control. Therefore detailed heat pump models can give very slow system simulations and still not so accurate results compared to real heat pump performance in a system. The idea here is to start from a standard measured performance map of test points for a heat pump according to EN 14825 and then determine characteristic parameters for a simplified correlation based model of the heat pump. By plotting heat pump test data in different ways including power input and output form and not only as COP, a simplified relation could be seen. By using the same methodology as in the EN 12975 QDT part in the collector test standard it could be shown that a very simple model could describe the heat pump test data very accurately, by identifying 4 parameters in the correlation equation found. © 2012 The Authors.

  • 163.
    Perers, Bengt
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Kovacs, P.
    Olsson, M.
    Persson, M.
    Pettersson, U.
    A tool for standardized collector performance calculations including PVT2012In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 30, p. 1354-1364Article in journal (Refereed)
    Abstract [en]

    A tool for standardized calculation of solar collector performance has been developed in cooperation between SP Technical Research Institute of Sweden, DTU Denmark and SERC Dalarna University. The tool is designed to calculate the annual performance of solar collectors at representative locations in Europe. The collector parameters used as input in the tool are compiled from tests according to EN12975, without any intermediate conversions. The main target group for this tool is test institutes and certification bodies that are intended to use it for conversion of collector model parameters (derived from performance tests) into a more user friendly quantity: the annual energy output. The energy output presented in the tool is expressed as kWh per collector module. A simplified treatment of performance for PVT collectors is added based on the assumption that the thermal part of the PVT collector can be tested and modeled as a thermal collector, when the PV electric part is active with an MPP tracker in operation. The thermal collector parameters from this operation mode are used for the PVT calculations. © 2012 The Authors.

  • 164.
    Perez de la Mora, Nicolas
    et al.
    Universidad de las Islas Baleares.
    Bava, Federico
    Technical University of Denmark.
    Andersen, Martin
    Dalarna University, School of Technology and Business Studies, Energy Technology. Chalmers University of Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Lennermo, Gunnar
    Mälardalens Hogskola.
    Nielsen, Christian
    PanEnergi.
    Furbo, Simon
    Technical University of Denmark.
    Martínes-Moll, Víctor
    Universidad de las Islas Baleares.
    Solar district heating and cooling: A review2017In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, p. 1-23Article in journal (Refereed)
    Abstract [en]

    Both district heating and solar collector systems have been known and imple- mented for many years. However, the combination of the two, with solar collec- tors supplying heat to the district heating network, is relatively new, and no comprehensive review of scientific publications on this topic could be found. Thus, this paper summarizes the literature available on solar district heating and presents the state of the art and real experiences in this field. Given the lack of a generally accepted convention on the classification of solar district heating systems, this paper distinguishes centralized and decentralized solar district heating as well as block heating. For the different technologies, the paper describes commonly adopted control strategies, system configurations, types of installation, and integration. Real‐world examples are also given to provide a more detailed insight into how solar thermal technology can be integrated with district heating. Solar thermal technology combined with thermally driven chillers to provide cooling for cooling networks is also included in this paper. In order for a technology to spread successfully, not only technical but also eco- nomic issues need to be tackled. Hence, the paper identifies and describes dif- ferent

  • 165.
    Perman, Karin
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Hedlund, G.
    Örebro university.
    WREF 2012: Gender, ethnicity and energy use in multi-family houses - Swedish norms in a multi-etnic context2012In: World Renewable Energy Forum, WREF 2012, Including World Renewable Energy Congress XII and Colorado Renewable Energy Society (CRES) Annual Conference / [ed] Cheryl Fellows, American Solar Energy Society , 2012, Vol. 3, p. 1834-1840Conference paper (Refereed)
    Abstract [en]

    The aim of this paper is to present data and analysis of an investigation of a renewal project in a big public housing area in a Swedish municipality. The project will combine the creation of at better quality of daily life in the multi- family housing area with the aim to reduce energy consumption. The area is in great need of renewal. We study the interaction between technological and social activities. Our theoretical approach in this study is the concept gendered.

  • 166.
    Persson, Björn
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Design and Implementation of a Supervisory Controller for PV and Storage2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Battery energy storage systems are a key factor for enabling a continuous increase of the fraction of photovoltaics in the Swedish electricity grid. One big challenge is to utilise all potential services of such a storage system. The aim of this study was to improve the supervisory controller for an existing battery storage and photovoltaic solution marketed by the Swedish company Ferroamp AB. This has been done by developing a combined peak reduction and time-of-use bill management algorithm, together with a simulation and evaluation software for optimisation of algorithm parameters. The algorithms and tools were evaluated using an installation made by Ferroamp AB and Vattenfall Eldistribution AB as a case study. Sensitivity analyses has been performed on economic parameters and length of the algorithm training data set. Improvement of economic profit, in this case study, were 300 % compared to the currently used algorithm and 32 % compared to a conventional threshold peak reduction algorithm. Despite this improvement, the battery energy storage system is shown to be non-profitable, with the economic profit only covering 36 % of the investment costs, not taking interest rate into account. Like in many other studies, power storage was found more profitable than energy storage. An increase of the grid power tariff and the grid energy fee of 30 % to 40 % is found to make the system viable. One interesting finding is that by using the proposed optimal algorithm, 55 % of the cycle life of the battery storage is still accessible for other services when considering 10 years of economic depreciation time for the system.

  • 167.
    Persson, Tomas
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Manikandan, Gokula
    Measurements of heat losses and energy labelling of storage tanks from Olle Jonsons Mekaniska, Hedemora2016Report (Other academic)
  • 168.
    Persson, Tomas
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Stavset, Ole
    SINTEF Energy Research.
    Ramstad, Randi Kalskin
    NTNU , Department of Geology and Mineral Resources Engineering.
    Alonso, Maria Justo
    SINTEF Energy Research.
    Lorenz, Klaus
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Software for modelling and simulation of ground source heating and cooling systems2016Report (Other academic)
    Abstract [en]

    The aim of this survey is to explore different simulation software for designing of ground source heating systems. Models to simulate borehole storages, heat pumps, and system components like water storages, hydraulics and building loads are explored. This study is based on a literature survey of software and models for simulation of geothermal heating and cooling systems with focus on vertical ground heat exchangers. The study focus on the software used by the authors, which are EED, TRNSYS, Polysun, Modelica, IDA ICE, and Matlab/Simulink+Carnot.  The scopes and limitations of the software and models are evaluated and the advantages and disadvantages with the software are addressed.  It was found that the user-friendliness is strongly linked to the level of flexibility in the models. Higher flexibility usually means less user-friendliness and more time to learn the tool. EED, Polysun and IDA are considered to be the more user friendly softwares, while Modelica, TRNSYS and Matlab/Simulink+Carnot are considered to be the more flexible softwares. The models covering most of the aspects of borehole simulations are the TRNSBM-model in TRNSYS and the “INTERACT 2016” model for Modelica.

  • 169.
    Persson, Tomas
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Wiertzema, Holger
    Win, Kaung Myat
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Modelling of dynamics and stratification effects in pellet boilers2019In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 134, p. 769-782Article in journal (Refereed)
    Abstract [en]

    Optimizing solar and pellet heating systems can be performed by system simulations in TRNSYS. However; this requires detailed boiler models that can properly model the thermal behaviour of the boilers, such as stratification and thermal response. This study uses a combination of existing models for modelling of the pellet burner part (TRNSYS Type 210) and the water volume (TRNSYS Type 340). This approach addresses the thermal dynamics and internal stratification more accurately than other available models. The objectives of this work are to develop a method for parameter identification for the model and to validate this method and the model itself. Sets of parameters are identified for two pellet boilers and one pellet stove with a water jacket (extended room heater) and the model is validated with a realistic dynamic operation sequence. The results show that modelling of stratification is essential in order to model the true behaviour of residential boilers. The test sequences used were adequate to parameterise the models and to provide the desired accuracy, except regarding the heat losses to room air. The model shows good accuracy for a stove and one boiler, but slightly worse performance for the other boiler regarding dynamics and modelling of the stratification.

    The full text will be freely available from 2021-01-01 15:49
  • 170.
    Pius Perangatt, George
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Evaluating the Economic Feasibility of Utilizing Power Optimizers in Various PVSystems2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Integration of power optimizers in photovoltaic systems is standard practice in some parts of the world. Manufacturers claim that optimizers can significantly reduce electrical losses due to shading. Hence, it is important to investigate this claim and determine under what conditions it is economically warranted to utilize optimizers.

    In this thesis systems were modelled in PVSyst, for 6 different locations: Abu Dhabi, Borlänge, Madrid, New Delhi, Sydney, and Vienna. In each location there were 3 types of systems: a regular non-optimised system, a SolarEdge optimised system and a TIGO optimised system. Each of these systems had 10 variants where the amount of shading was varied. The system variants were simulated in PVSyst and the effect of power optimizers on electrical losses due to shading was analysed. Afterwards, payback periods were calculated for each system to determine under which conditions power optimizers are economically feasible.

    It was found that power optimizers significantly reduce electrical losses due to shading. In some scenarios, the losses were reduced by up to 58 %. However, in the current economic climate in 2018, it is not feasible to incorporate power optimizers, in photovoltaic systems in Abu Dhabi, New Delhi or Sydney. Furthermore, in Borlänge, Madrid, and Vienna, optimizers are only feasible if there are high levels of shading, which is not realistic for a regular photovoltaic system.

  • 171.
    Poppi, Stefano
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Solar heat pump systems for heating applications: Analysis of system performance and possible solutions for improving system performance2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Solar heat pump systems (SHPs) are systems that combine solar energy and heat pumps. SHPs have been investigated for several decades and have been proven to increase the share of renewable energy and reduce electric energy demand in residential heating applications. Many solar thermal heat pump systems have become market-available in recent years; however these systems are still not widely employed in the residential sector. This is due mainly to the high initial costs (investment and installation costs) of solar thermal heat pump systems, which limits their cost-effectiveness. Enhancing cost-effectiveness of solar thermal heat pump systems is necessary for a more effective and broader market penetration.

    In this thesis, solar thermal and photovoltaic systems combined with heat pumps for heating applications are treated. The overall aims of the thesis are to: 1) investigate techno-economics of SHPs and 2) investigate possible solutions for improving system performance of a reference solar thermal and heat pump system for residential heating applications.

    In the first part of the thesis, the influence of climatic boundary conditions on economic performance of SHPs has been investigated by means of: a) an economic comparison of SHPs found in the relevant literature and b) system simulations of the reference solar thermal heat pump system.

    In the second part of the thesis, potential solutions for improving system performance of the reference solar thermal heat pump system with limited change in system’ costs are investigated. A systematic approach was used for investigating cost-effectiveness of the system improvements in the reference system.

    Based on results of the cost-effectiveness analysis, some of the investigated system improvements were chosen for being included in the design of a novel solar thermal and air source heat pump system concept. The novel system was designed for a house standard with relatively high operating temperatures (55°C/45°C) in the space heating distribution system and for high space heating demand (123 kWh/m2·year). Finally, the thesis ends with a cost-effectiveness analysis of the novel system.

  • 172.
    Poppi, Stefano
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Department of Energy Technology, KTH.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Influence of hydraulics and control of thermal storage in solar assisted heat pump combisystems2014In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 48, p. 946-955Article in journal (Refereed)
    Abstract [en]

    This paper studies the influence of hydraulics and control of thermal storage in systems combined with solar thermal and heat pump for the production of warm water and space heating in dwellings. A reference air source heat pump system with flat plate collectors connected to a combistore was defined and modeled together with the IEA SHC Task 44 / HPP Annex 38 (T44A38) “Solar and Heat Pump Systems” boundary conditions of Strasbourg climate and SFH45 building. Three and four pipe connections as well as use of internal and external heat exchangers for DHW preparation were investigated as well as sensor height for charging of the DHW zone in the store. The temperature in this zone was varied to ensure the same DHW comfort was achieved in all cases. The results show that the four pipe connection results in 9% improvement in SPF compared to three pipe and that the external heat exchanger for DHW preparation leads to a 2% improvement compared to the reference case. Additionally the sensor height for charging the DHW zone of the store should not be too low, otherwise system performance is adversely affected

  • 173.
    Poppi, Stefano
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Techno-economic analysis of a novel solar thermal and air-source heat pump system2016Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    This paper presents a techno-economic analysis of a novel solar thermal and air source heat pump system. The system was designed for relatively high operating temperatures in the space heating circuit and included the use of a heat pump with vapor injection cycle and vacuum insulation on the storage tank. The system model was validated against measurements in laboratory and simulated in TRNSYS 17. Annual simulations were performed for the combination of two climates (Carcassonne and Zurich) and two house standards (SFH45 and SFH100) and the best results were achieved for the boundary conditions the system was designed for. For those conditions (Zurich and SFH100), the novel system showed potential for being cost-effective compared to state of art solar and heat pump system. The “additional investment limit”, i.e. the maximum extra investment cost for the novel system in comparison to a state of art benchmark system that gives a break even result for a period of 10 years, varied between 827 € and 2482 € depending on electricity price. The results of a sensitivity analysis showed that variations in electricity price affected the additional investment limit far more than the other economic parameters

  • 174.
    Poppi, Stefano
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Haller, Michel Y.
    University of Applied Sciences HSR, Switzerland.
    Heinz, Andreas
    Institute of Thermal Engineering, Graz University of Technology.
    Influence of boundary conditions and component size on electricity demand in solar thermal and heat pump combisystems2016In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 162, p. 1062-1073Article in journal (Refereed)
    Abstract [en]

    Solar thermal and heat pump combisystems are used to produce domestic hot water (DHW) and space heating (SH) in dwellings. Many systems are available on the market. For an impartial comparison, a definite level of thermal comfort should be defined and ensured in all systems. This work studied the influence of component size on electricity demand for a state of the art solar thermal and heat pump system. A systematic series of parametric studies was carried out by using TRNSYS to show the impact of climate, load and size of main components as well as heat source for the heat pump. Penalty functions were used to ensure that all variations provided the same comfort requirements. Two reference systems were defined and modelled based on products on the market, one with ambient air and the other with borehole as heat source for the heat pump. The results show that changes in collector area from 5 to 15 m2 result in a decrease in system electricity of between 305 and 552 kW h/year. Changes in heat exchanger size for DHW preparation were shown to give nearly as large changes in electricity use due to the fact that the set temperature in the store was changed to give the same thermal comfort in all cases. Decrease in heat pump size was shown to give a decrease in electricity use for the ASHP in the building with larger heat demand while it increased or had only a small change for other boundary conditions. Heat pump losses were shown to be an important factor highlighting the importance of modelling this factor explicitly

  • 175.
    Poppi, Stefano
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Heinz, Andreas
    Hengel, Franz
    Cheze, David
    Mojic, Igor
    Cialani, Catia
    Dalarna University, School of Technology and Business Studies, Economics.
    Analysis of system improvements in solar thermal and air source heat pump combisystems2016In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 173, p. 606-623Article in journal (Refereed)
    Abstract [en]

    A solar thermal and heat pump combisystem is one of many system alternatives on the market for supplying domestic hot water (DHW) and space heating (SH) in dwellings. In this study a reference solar thermal and air source heat pump combisystem was defined and modelled based on products available on the market. Based on the results of an extensive literature survey, several system variations were investigated to show the influence of heat pump cycle, thermal storage and system integration on the use of electricity for two houses in the climates of Zurich and Carcassonne. A singular economic cash flow analysis was carried out and the “additional investment limit” of each system variation was determined for a range of economic boundary conditions. This is the maximum extra investment cost for the system variant compared to the reference system that will give a break even result for a 10 year period. The results show that variations in electricity price affects the additional investment limit far more than the other economic parameters. Several of the variants show potential for achieving a cost benefit, but the potential varies a lot depending on load and climate boundary conditions. For all variants, the biggest difference in electricity savings was found for Zurich rather than in Carcassonne, which is explained by the larger heating load. However, in three cases the largest savings were for the SFH45 house despite the fact that the annual electricity use of the system is much lower than that for the SFH100 house, 3581 kW h/year compared to 8340 kW h/year. This was attributed to the fact that, in these cases, the operating level of the space heating circuit played a significant role, the SFH45 house being supplied with a 35/30 °C heating system while the SFH100 was supplied with a 55/45 °C heating system.

  • 176.
    Poppi, Stefano
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Sommerfeldt, N.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Madani, H.
    Lundqvist, P.
    Techno-economic review of solar heat pump systems for residential heating applications2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, p. 22-32Article in journal (Refereed)
    Abstract [en]

    Solar heat pump systems (SHPs) have been investigated for several decades and have been proven to increase the share of renewable energy and reduce electric energy demand in residential heating applications. Many review articles have been published on the subject, however literature discussing the techno-economics of different solar technologies (thermal, photovoltaic and hybrid thermal/photovoltaic) in combination with heat pumps is lacking, and thus to directly compare the merits of different SHPs is not an easy task. The objectives of this study are: a) review the different system boundaries and the main performance indicators used for assessing energetic and economic performances; b) review techno-economic studies in the literature and identify which studies give enough information and are compatible enough for making an economic inter-comparison; c) present an economic inter-comparison based on the identified systems. The results show that there is a lack of studies including an economic assessment of solar photovoltaic and heat pump systems. Additionally, there are no consistent boundaries or approaches to the study structures, making comparisons between systems difficult. In conclusion, a standardized or broadly accepted definition of technical and economic performance for SHPs is needed. Despite this, the study has shown that there are clear trends for decreasing payback times for SHPs, both solar thermal (ST) and photovoltaic (PV), with decreasing heating degree-days and with increasing solar resource.

  • 177.
    Psimopoulos, Emmanouil
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Bee, E.
    Luthander, R.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Smart control strategy for PV and heat pump system utilizing thermal and electrical storage and forecast services2017Conference paper (Refereed)
  • 178.
    Psimopoulos, Emmanouil
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Uppsala University.
    Bee, Elena
    University of Trento, Trento, Italy.
    Luthander, Rasmus
    Uppsala University.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Smart control strategy for PV and heat pump system utilizing thermal and electrical storage and forecast services2017Conference paper (Refereed)
    Abstract [en]

    In this study, a detailed model of a single-family house with exhaust air heat pump, PV system and energy hub developed in the simulation software TRNSYS 17 is used to evaluate energy management algorithms that utilize weather and electricity price forecasts. A system with independent PV and heat pump is used as a base case. The proposed control strategy is applied to the base case to optimize the available PV electricity production using short-term weather and electricity price forecasts. The three smart and predictive control algorithms were developed with the scope to minimize final energy by the use of the thermal storage of the building, the hot water tank and electrical storage. The results show reduction of the final energy of 26.4%, increase of the self-consumption to 60% and decrease of the annual cost of 15% when using the forecast services in combination with thermal and electrical storage compared to the base case.

  • 179.
    Psimopoulos, Emmanouil
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Uppsala universitet.
    Leppin, Lorenz
    Luthander, Rasmus
    Uppsala universitet, Fasta tillståndets fysik.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Control algorithms for PV and Heat Pump system using thermal and electrical storage2016In: Proceedings of the 11th ISES EuroSun 2016 International Conference on Solar Energy for Buildings and Industry, Palma de Mallorca, Spain, 11-14 October 2016, International Solar Energy Society , 2016Conference paper (Other academic)
    Abstract [en]

    In this study a detailed model of a single-family house with an exhaust air heat pump and photovoltaic system is developed in the simulation software TRNSYS. The model is used to evaluate three control algorithms using thermal and electrical storage in terms of final energy, solar fraction, self-consumption and seasonal performance factor. The algorithms are tested and compared with respect to energetic improvement for 1) use of the heat pump plus storage tank for domestic hot water and space heating, 2) use of the electrical storage in batteries and 3) use of both electrical and thermal storage. Results show the highest increase of self-consumption to 50.5%, solar fraction to 40.6% and final energy decrease to 6923 kWh by implementing the third algorithm in a system with 9.36 kW PV capacity and battery storage of 10.8 kWh. The use of electrical energy storage has higher positive impact compared to the thermal storage with the settings and component sizes used. The combined use of thermal storage and batteries leads to final energy savings that are nearly the same as the combined savings of thermal storage and batteries separately, showing that they are mostly independent of one another for the settings of this study.

  • 180.
    Quintana, Samer
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Building integrated photovoltaic (BIPV) modelling for a demo site in Ludvika based on building information modelling (BIM) platform2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to design and simulate a building integrated photovoltaic (BIPV)

    system for three demo buildings in Ludvika, Sweden, which is part of the Energy-

    Matching’s project under the European H2020 research scheme. A literature

    review was firstly conducted in the area of energy scenarios, engineering tools,

    methodologies and the workflows in design and building energy modelling. Then,

    this thesis developed the three-dimensional (3D) building models of the demo

    site, based on the Revit – a building information modelling (BIM) tool. Next, the

    PVSITES tool was considered as the main approach to simulate and optimize the

    BIPV system. Results on the energy output of the dedicated BIPV system, as well

    as financial costs, were finally obtained. It was found that the optimal location for

    the BIPV system was on the three buildings south and east faced roofs, with a total

    area of approximately 800 meters squared (m2) and a yearly irradiance potential

    between 1020 kilowatts hours per meter squared (kWh/m2) and 925 kWh/m2

    respectively. The simulation showed that this BIPV system of 615 m2 with a power

    of 36 kilowatts-peak (kWp) could yield a maximum of 29,000 kilowatts hours per

    year (kWh), a 5% of the total yearly energy demand of the building and over the

    summer, this percentage increases considerably. With the estimated standards

    costs, the BIPV system have a 12 years payback period and 61% investment ratio

    over a 20 years period, concluding that a BIPV system on the Ludvika demo

    building is a feasible project, in terms of energy potential and as well as

    economically. This thesis also concludes that performing the BIPV simulation on

    the BIM platform is both reliable and flexible, and also has the potential to be

    reused, refined and scaled up.

  • 181.
    Radoglou, Kalliopi
    et al.
    Democritus University of Thrace.
    Sismanis, Nikos
    Democritus University of Thrace.
    Smirnakou, Sonia
    Democritus University of Thrace.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Schirone, Bartolomeo
    Universita degli Studi della Tuscia.
    Marras, Tatiana
    Universita degli Studi della Tuscia.
    Vessella, Federico
    Universita degli Studi della Tuscia.
    Chiatante, Donato
    Università degli Studi dell'Insubria.
    Terzaghi, Mattia
    Università degli Studi dell'Insubria.
    Fulgaro, Nicoletta
    Università degli Studi dell'Insubria.
    Montagnoli, Antonio
    Università degli Studi dell'Insubria.
    ZEPHYR Project – Deliverable D3.2: Intermediate report on growth tests2014Report (Other (popular science, discussion, etc.))
  • 182.
    Ramaswamy Iyyaswamy, Prashanth
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Performance Analysis of a Building Integrated Photovoltaic System in Norway2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis, performance of the PV system on the facade of the Oseana building is

    evaluated. The thesis was done at the Institute for Energy Technology (IFE), which is

    situated in Kjeller, Norway. The building of the PV system that is being analyzed in this

    thesis is situated in Osøyro, Os Kommune, which is located south of Bergen. The analysis

    was carried out by modelling the building and the PV system in PVsyst, a software package

    specifically used for sizing, simulation and analysis of complete PV systems. Simulations

    were performed on user-defined models based on the original system, whilst considering

    different cases, the results from these simulations were compared to the inverter output

    data, and conclusions were derived.

    The building with the PV system under study has a unique architecture, having a curved

    facade with the panels mounted on this curved facade. The facade also has a walkway

    coming out of the third floor window, which causes shading. The effects of the shading

    caused by the walkway were analyzed. Simulations were carried out for different cases and

    the results were compared to derive conclusions.

    Different weather data sources were considered and used in the base simulations to

    identify the most relevant data source. Once the best data source was identified, further

    simulations were carried out to generate outputs such as the system’s annual yield, losses

    and performance ratio. These simulation outputs were then compared with the actual

    annual outputs of the system. The performance ratios of the simulated systems, with and

    without the walkway are obtained and a comparison between them is made. The probable

    values of global horizontal irradiance are calculated and these values were compared with

    the annual yield of the system to check if the data would match. Probability simulations

    were also carried out to determine the percentage chance that the system would yield a

    certain output value in any given year. Furthermore, the orientation of the PV plane of the

    PV system was changed by altering the tilt angles

  • 183.
    Ramírez Villegas, Ricardo
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    A methodology to assess impacts of energy efficient renovation - A Swedish case study2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The European Union aims to reduce energy use and CO2-emissions by 40 % by the year 2030. The building sector has been identified as having a great potential to reduce emission of CO2 by increasing its energy efficiency. Also, there is a growing concern of the buildings environmental performance, that lead to the development of building environmental assessment tools. However, different types of energy sources and confusing environmental impacts affect the decision making when renovating for improved energy efficiency. This study develops and tests a methodology to help decision-makers when considering major renovation of their building stock when connected to adistrict heating system. The proposed methodology is applied and used to investigate how different renovation scenarios affects the building environmental impacts in terms of CO2 emissions and identify and discuss future improvements of the methodology.

    The novelty of the method is the expanded system boundaries that include both the distribution and production of district heating and the energy use at a building level. In this way it is possible to compare and weight measures made both at the energy system level and the building level. This work has limited its approach to energy use in buildings, but it is important to bring the life cycle thinking to the methodology. During the choice of the renovation methods it was noticed that the environmental impact of the production of some components in order to reduce the energy use of a building are not insignificant. Even if all the renovation measures considered in this case study are feasible, it is important to determine in which order they are desirable or achievable from an economic point of view. Uncertainty in the future development of energy, and limited economic resources can play an important role in the possibility of energy efficient renovation.

  • 184.
    Ramírez Villegas, Ricardo
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. University of Gävle.
    Eriksson, O.
    Olofsson, T.
    Life cycle assessment of building renovation measures–trade-off between building materials and energy2019In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 3, article id 344Article in journal (Refereed)
  • 185.
    Ramírez Villegas, Ricardo
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Eriksson, Ola
    Högskolan i Gävle.
    Olofsson, Thomas
    Dalarna University, School of Technology and Business Studies, Construction. Umeå universitet.
    Assessment of renovation measures for a dwelling area: impacts on energy efficiency and building certification2016In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 97, p. 26-33Article in journal (Refereed)
    Abstract [en]

    The European Union has an ambitious plan to reduce energy use and emissions by the year 2030. The building and real estate sectors have a great potential to help reduce emissions by energy efficiency. However, different energy sources and environmental standards affect the decision making of these major renovations in the existing stock. This study investigates how different renovation strategies affect the energy rating of a selected Building Environmental Assessment Tool and analyses the consequences in terms of greenhouse gas emissions for the local district heating system. Both building energy simulations and energy systems cost optimization were used to determine the energy use and local emissions. The results of different renovation scenarios were used to evaluate the rating in the selected tool and the impact in the district heating local emissions. The used methodology illustrates how energy efficient renovation impacts on the district heating system’s local emissions. However, a bias towards resource classification within the Swedish Building Environmental Tool, Miljöbyggnad, needs to be addressed in order to assess the impact of local emissions. © 2015 Elsevier Ltd.

  • 186.
    Rasch, André
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Utvärdering av Ngenic Tune: Smart styrning av värmesystem i småhus2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In 2016, the global energy consumption was represented to 20 % by buildings, where energy use supplied heating, cooling, lightning and water heating. For the following years until 2040, global energy consumption is expected to grow 48 %, which in turn make demand for energy efficient measures. For the years of 2030 as well 2050, the EU-commission have set up climate goals to reduce global greenhouse gas emissions. Along with this were presented strategies for meeting future climate goals, where one strategy is about increasing overall energy efficiency, which includes buildings. One way of increasing building energy efficiency is through implementation of smart heating control, a cost-effective solution which through a retrofitting measure may reduce building energy consumption. For this paper, a smart thermostat named Ngenic Tune was implemented into a selection of single family houses in Borlänge district heating network. The purpose was to study improvements in thermal comfort and reduction of return temperature from domestic substations. Through a combined survey-interview study of Ngenic Tune users, the study revealed promising potentials for large scale implementation of the technology. The smart thermostat also showed tendency of lowering the return temperature.

  • 187. Ren, Guangying
    et al.
    Sunikka-Blank, Minna
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    The Influence of Variation in Occupancy Pattern on Domestic Energy Simulation Prediction: A Case Study in Shanghai2017Conference paper (Refereed)
  • 188.
    Rizos, Konstantinos
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Design Synthesis and Characterization of New Hybrid Derivatives for Dye Sensitized Solar Cells (DSSCs) Based on Porphyrin Rings2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sunlight is the most abundant and one of the cleanest sources of energy. Nature harnesses solar energy very efficiently via the photosynthetic process. A tremendous effort has been expended at learning from natural photosynthesis and creating artificial systems for solar energy applications based on porphyrins that are key light – absorber components of successful solar cells. Dye-sensitized solar cells (DSSCs) establish an innovative class of hybrid organic-inorganic solar cells. The device consists of a mesoporous film of titanium dioxide (TiO2) nanoparticles, coated with a dye monolayer. The role of the dye in DSSCs is similar to the role of chlorophyll in plants and its presence guarantees the sensitivity of the DSSC in the visible part of the solar spectrum, by gathering solar light and transferring the energy via electron transfer to an appropriate material to produce electricity. To date the highest solar energy to electricity conversion efficiencies have reached ~13%. The principal aim of this thesis is the synthesis and characterization of new porphyrin bioinorganic sensitizers for DSSCs. The synthesis part has used a modified synthetic approach by the Coutsolelos group that has successfully produced a new porphyrin product. The base porphyrin was prepared by the trifluoroacetic acid (TFA) catalyzed condensation following a modified procedure. The porphyrin was purified by silica gel column chromatography using dichloromethane. Metallation of porphyrin by Zn was done in the chloroform–methanol mixture followed by the chromatographic purification. The new porphyrin product was subsequently characterized with Ultraviolet – Visible (UV-VIS), Nuclear Magnetic Resonance (NMR), and Matrix Assisted Laser Desorption/Ionization Time of Flight (MALDI-TOF) spectroscopies that have verified the formation of the end product. The characterization shows that the new synthesized porphyrin has characteristics very similar to that of the porphyrin complex with the record efficiency of 13%.

  • 189.
    Rozas Barrio de Mendoza, Andrés Arturo
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Design, Implementation and Performance Evaluation of an Off-grid Photovoltaic Powered Grain Mill without Battery Storage Master2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Many rural communities in developing countries still do not have access to electricity, however, inhabitants of those communities must still perform energy demanding activities. Such is the case of milling grains to fulfill their food intake. This activity, in many cases, is still performed manually.

    This research project aims in providing a solution to the aforementioned problem by designing, implementing and testing a grain mill powered solely by means of photovoltaic energy. It is intended to avoid the use of an intermediate battery in order to reduce the initial and possible running costs of the solution.

    The project development included testing the operation of the mill under different speeds and loads to acknowledge the torque profile and accurately size the corresponding motor. A brushless direct current motor together to its speed controller was selected to drive the mill. The operation of the mill was tested under constant and variable power source to characterize the electrical performance and size a suitable photovoltaic module. Also, the quality of the flour and output rate were analyzed.

    A modified maximum power point tracker controller was designed and implemented based on a microcontroller (Arduino Uno board). The perturb and observe as well as the incremental conductance maximum power point tracking methods were implemented and analyzed to be used as the basis of the modified tracking algorithm.

    The overall performance of the designed controller was evaluated using a modified test procedure based on the EN 50530 standard, which indicates how to evaluate the static and the dynamic efficiency of the maximum power point trackers in grid connected inverters.

    The proposed controller achieved an average static efficiency of 47 % while milling corn and 55 % while milling wheat, based on the weighting factors defined in the European efficiency. Moreover, the controller reached an average dynamic efficiency of 50 % while milling corn and 62 % while milling wheat during the test with irradiance change from medium to high levels (300 W/m2 to 1000 W/m2). Finally, the average flour output rate while milling corn was measured as 3.25 kg/h while milling corn and 5.38 kg/h while milling wheat.

  • 190.
    Selva Marti, Salvador
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Aerial Thermography Inspections in Large-Scale PV Plants2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In order to successfully compete against the use of fossil fuels to generate electricity, one of the challenges in the photovoltaic (PV) business currently in focus is on the asset management of large PV plants, in which developing control techniques to prognosticate and evaluate the future energy performance will be essential. Infrared thermography inspections can give meaningful support to assess the quality and performance of PV modules. However, the implementation of a cost-effective method to scan and check huge PV plants represents different challenges, such as the cost and time of detecting PV module defects with their classification and exact localization within the solar plant. In this context, it has recently been investigated the potential of a new innovative technology in the PV plants monitoring operations by using drones.

    The main purpose of this work is to establish a scientific basis for the interpretation of thermographic images taken by drones, in particular, regarding the influence of thermographic irregularities which will negatively influence the performance of PV plants.

    The drone is employed to monitor PV modules conditions by using special thermography sensors mounted on it in order to scan images. The captured images are then automatically sent to a technical office database for the image processing software. This special software receives, stores and analyses the captured images to detect the specific defect on the PV modules. Then, all information is processed and reported to the final decision-making team to decide about the best solution for the particular degraded PV module, in relation with the requirements from the operation and maintenance (O&M) services.

    In this particularly study project of the inspected PV plant situated in the UK, which has been carried out by trained personnel at Quintas Energy (QE), the majority of identified faults, which influence the PV module performance (especially the power output significantly), are on a sub-panel level, either individual cells or uneven hot spots. There are also some modules with bypass diode faults as well as a string fault was detected. Such faults must be repaired by the PV module manufacturer, in relation to the manufacturer’s warranties, without any cost at all since the PV modules are indeed still in warranty.

    It has been concluded that, in comparison with traditional manned systems by using hand-held cameras, the main functionality of using drones is the early fault diagnosis which could reduce corrective maintenance activities, since defects are easily and quickly identified and, then, repaired. This fact could reduce defects to become more serious and, thus, more difficult to be repaired, along with their correspondent production losses and costs.

    QE has learned by making mistakes during this project study and gained experience of this unmanned aerial vehicles (UAV) technology. Currently, they are in the process of improving this technique and will continue to implement it to all their PV plants since the efficiency of PV systems can be significantly improved by appropriate use of O&M instruments and benefit from innovative monitoring tools, such as the unmanned aerial technology.

  • 191.
    Sharma, Raushan
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    PVT Roof Integrated System – Technical and Economic Feasibility for an Agricultural Building2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Modern agriculture is profoundly reliant on use of fossil fuels and with the vision of transferring those uses to renewable energy sources, a hybrid photovoltaic thermal system (PVT) has been designed in this study to use the cogenerated heat for crop drying while generating green electricity.

    The designed PVT system will use a fan to extract the heat and provide the optimal thermal energy during crop drying period and will be used in passive mode to improve the electrical efficiency of the system during rest of the period. The main aim of this study is to quantify the output from the designed PVT system with its economic evaluations.

    A novel methodology is developed by using the simulated output from grid connected PV system as an input for modelling the PVT system using steady state equations in Microsoft Excel. Parameters such as duct depth, air mass flow rate and corresponding fan electrical power requirements were optimized using batch simulations for providing optimal thermal and electrical output from the system.

    The thermal energy efficiency of the designed PVT system using copper indium gallium selenide (CIGS) cells was predicted to be 28 % with the electrical efficiency improvement by 2 % for forced cooling and around 1 % during passive air flow. The designed PVT system will have a payback period of 13 years with the current financial regulations and framework in Sweden.

  • 192. Sotnikov, A.
    et al.
    Nielsen, C. K.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Dalenbäck, J. -O
    Andersen, Martin
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Psimopoulos, Emmanouil
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Simulations of a Solar-Assisted Block Heating System2017Conference paper (Refereed)
  • 193.
    Swing Gustafsson, Moa
    Dalarna University, School of Technology and Business Studies, Energy Technology. Mälardalen University.
    The impact on the energy system of heating demands in buildings: A case study on district heating and electricity for heating in Falun, Sweden2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energy efficiency measures in buildings are considered to have great potential in order to reduce total energy consumption, and thus contribute to a reduced environmental impact and a better climate. In Sweden, however, the energy performance requirements for buildings are formulated in terms of bought energy, i.e. as bought electricity and district heating (DH), which does not always reflect the environmental and climate impact from a broader perspective. Focusing on bought energy means that many choose an electricity-based heat pump solution in their building instead of DH, since heat pumps result in a smaller amount of bought energy compared to DH.

    The surrounding energy system of the buildings is affected by the choice of energy carriers used for heating. How the energy system is affected is studied in this thesis using two different methods. In the first part, primary energy consumption has been calculated for a simulated building with different heating solutions, representing different electricity and DH demands. In the second part, the impact on total consumption in the surrounding power and DH networks due to different market shares of electricity-based heating and DH has been studied. The second part also includes an analysis of the potential to produce electricity using combined heat and power (CHP) in different scenarios depending on the market share of DH. This part has been carried out as a case study for the Swedish municipality of Falun.

    The results show that the choice of energy carrier has a great influence on primary energy consumption. The resulting primary energy consumption does, however, to an even greater extent depend on the calculation method used. Which heating solution, and thus also which energy carrier, gets the lowest primary energy consumption varies in the different methods.

    The surrounding power and DH networks are also affected to a great extent by the choice of energy carrier. There is a huge potential to lower peak demand in the power grid by avoiding electricity-based heating. The potential to produce electricity using CHP is also increased with a larger market share for DH. In Falun, reduced electricity demand and increased electricity production using CHP make it possible to cover the peak power demand using only electricity production from CHP. In comparison, 10 % of the peak power demand was covered by electricity from CHP in 2015.

    The choice of energy carrier for heating in buildings affects the surrounding energy system to a high degree, and is therefore an important aspect to take into account in both local, national and global energy efficiency projects. 

  • 194.
    Swing Gustafsson, Moa
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Mälardalen University.
    Gustafsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Dotzauer, Erik
    Mälardalen University.
    Primary energy use in buildings in a Swedish perspective2016In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 130, p. 202-209Article in journal (Refereed)
    Abstract [en]

    The building sector accounts for a large part of the energy use in Europe and is a sector where the energy efficiency needs to improve in order to reach the EU energy and climate goals. The energy efficiency goal is set in terms of primary energy even though there are different opinions on how to calculate primary energy. When determining the primary energy use in a building several assumptions are made regarding allocation and the value of different energy sources. In order to analyze the difference in primary energy when different methods are used, this study use 16 combinations of different assumptions to calculate the primary energy use for three simulated heating and ventilations systems in a building. The system with the lowest primary energy use differs depending on the method used. Comparing a system with district heating and mechanical exhaust ventilation with a system with district heating, mechanical exhaust ventilation and exhaust air heat pump, the former has a 40% higher primary energy use in one scenario while the other has a 320% higher in another scenario. This illustrates the difficulty in determining which system makes the largest contribution to fulfilling the EU energy and climate goals.

  • 195.
    Swing Gustafsson, Moa
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Mälardalen University.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Dotzauer, Erik
    Mälardalen University.
    Assessment of the potential for district heating to lower the peak electricity consumption in a medium size municipality in SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    Sweden faces several challenges when more intermittent renewable power is integrated into the energy system. One of the challenges is to have enough electrical power available in periods with low production from intermittent sources. A solution to the problem could be to reduce the electricity peak demand and at the same time produce more electricity during peak hours. One way of doing this is to convert electricity based heating in buildings to district heating (DH) based on combined heat and power (CHP).

    The study analyzes how much a medium sized Swedish municipality can contribute to lower the electricity peak demand. This is done by quantifying the potential to reduce the peak demand for six different scenarios of the future heat market volume and heat market shares regarding electricity based heating and DH in 2050.

    The main finding is that electricity consumption will be reduced by 35-70 % during the peak hour (and 20-40 % on a yearly basis) for all the six scenarios studied compared with the current situation. If the aim is to lower the electricity peak demand in the future, the choice of heating system is more important than reducing the heat demand itself. For the scenario with a large share of DH, it is possible to cover the electricity peak demand in the municipality by using CHP.

  • 196.
    Swing Gustafsson, Moa
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Life cycle cost of heat supply to areas with detached houses: a comparison of district heating and heat pumps from an energy system perspective2018In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, no 12, article id 3266Article in journal (Refereed)
    Abstract [en]

    There are different views on whether district heating (DH) or heat pumps (HPs) is or are the best heating solution in order to reach a 100% renewable energy system. This article investigates the economic perspective, by calculating and comparing the energy system life cycle cost (LCC) for the two solutions in areas with detached houses. The LCC is calculated using Monte Carlo simulation, where all input data is varied according to predefined probability distributions. In addition to the parameter variations, 16 different scenarios are evaluated regarding the main fuel for the DH, the percentage of combined heat and power (CHP), the DH temperature level, and the type of electrical backup power. Although HP is the case with the lowest LCC for most of the scenarios, there are alternatives for each scenario in which either HP or DH has the lowest LCC. In alternative scenarios with additional electricity transmission costs, and a marginal cost perspective regarding the CHP investment, DH has the lowest LCC overall, taking into account all scenarios. The study concludes that the decision based on energy system economy on whether DH should expand into areas with detached houses must take local conditions into consideration.

  • 197.
    Swing Gustafsson, Moa
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. Mälardalen University.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Dotzauer, Erik
    Mälardalen University.
    Mapping of heat and electricity consumption in a medium size municipality in Sweden2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, p. 1434-1439Article in journal (Refereed)
    Abstract [en]

    The Nordic electricity system faces many challenges with an increased share of intermittent power from renewable sources. One such challenge is to have enough capacity installed to cover the peak demands. In Sweden these peaks appear during the winter since a lot of electricity is used for heating. In this paper a mapping of the heat and electricity consumption in a medium size municipality in Sweden is presented. The paper analyze the potential for a larger market share of district heating (DH) and how it can affect the electrical power balance in the case study. The current heat market (HM) and electricity consumption is presented and divided into different user categories. Heating in detached houses not connected to DH covers 25 % of the HM, and 30 % of the electricity consumption during the peak hours. Converting the detached houses not connected to DH in densely populated areas to DH could reduce the annual electricity consumption by 10 %, and the electricity consumption during the peak hours by 20 %.

  • 198.
    Swing Gustafsson, Moa
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Dotzauer, Erik
    Potential for district heating to lower peak electricity demand in a medium-size municipality in Sweden2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 186, p. 1-9Article in journal (Refereed)
    Abstract [en]

    Sweden faces several challenges with more intermittent power in the energy system. One challenge is to have enough power available in periods with low intermittent production. A solution could be to reduce peak demand and at the same time produce more electricity during these hours. One way of doing this is to convert electricity-based heating in buildings to district heating based on combined heat and power. The study analyzes how much a Swedish municipality can contribute to lowering peak electricity demand. This is done by quantifying the potential to reduce the peak demand for six different scenarios of the future heat demand and heat market shares regarding two different energy carriers: electricity-based heating and district heating. The main finding is that there is a huge potential to decrease peak power demand by the choice of energy carrier for the buildings’ heating system. In order to lower electricity peak demand in the future, the choice of heating system is more important than reducing the heat demand itself. For the scenario with a large share of district heating, it is possible to cover the electricity peak demand in the municipality by using combined heat and power.

  • 199.
    Swing Gustafsson, Moa
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Primary energy reduction in buildings: Case study on a residential building in Falun, Sweden2014In: Proceedings from the 14th International Symposium on District Heating and Cooling / [ed] Anna LAND, Swedish District Heating Association, 2014, p. 543-545Conference paper (Refereed)
    Abstract [en]

    Since a large share of the total European primary energy is consumed in the building sector, buildings have to become more energy efficient in order to reach the goals of the European energy efficiency directive. In Sweden, focus has been on lowering final energy consumption, not primary energy consumption. A relevant question today is whether a general understanding of the primary energy concept is needed to encourage selection of better energy efficiency measures from an environmental perspective. There are however uncertainties of how to calculate primary energy consumption since different primary energy factors (PEF) are used by different actors, especially for district heating (DH) and electricity (EL.).

    In this study total primary energy consumption was calculated for a residential building before and after several renovation measures were made. The major change after the renovation was that a large share of the DH was substituted by heat from an exhaust air heat pump and solar collectors. A range of commonly used PEFs were assessed.

    The evaluation showed that the energy efficiency measures reduced the total primary energy consumption for most combinations of PEFs. The most essential was how the DH was valued. A low PEF for DH in combination with most of the PEFs for electricity could even result in higher total primary energy consumption after the renovation.  

  • 200. Takács, Ágnes
    et al.
    Gál, Csilla V
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Gulyás, Ágnes
    Kiss, Márton
    Kántor, Noémi
    Radiation conditions at a Central European square in a hot summer day, a case study from Szeged, Hungary2017In: 97th Annual Meeting of the American Meteorological Society (AMS) jointly with the 13th Symposium on the Urban Environment, Seattle, WA, 2017Conference paper (Other academic)
    Abstract [en]

    In the light of sustained urbanization and rising temperature trends, mitigating the impact of extreme heat events is a pressing urban planning issue. Radiation heat load, quantified as mean radiant temperature (Tmrt), has been identified as the main source of summer heat stress. Several studies ascertained that Tmrt is the key factor driving human thermal comfort in outdoor urban places. Shading that reduces radiation heat load (Tmrt) is the most effective means to mitigate heat stress in outdoor public places, which offer a venue for leisure, recreation and for the social life of residents. Nonetheless, the small-scale thermal conditions of urban places are not only governed by shade trees and greenery, but also by buildings and paved surfaces. The aim of this study is twofold. First, it assesses the impact of differently oriented street facades with varying solar exposure on the human radiation balance at a medium-sized square in a mid-latitude city. Second, it evaluates the performance of popular, freely available microclimate and radiation models in deriving Tmrt values. The well-vegetated, rectangular Bartók square was selected in Szeged, Hungary to calculate various radiation parameters using three numerical simulation models (ENVI-met, SOLWEIG and RayMan). The derived parameters (radiation flux densities from different directions, as well as Tmrt) are compared with corresponding values obtained from detailed on-site measurements. The field data are collected as part of a 24-hour long radiation measurement utilizing the six-directional method, where a set of pyranometers and pyrgeometers are used to record short- and long-wave flux densities from six perpendicular directions (from above, from below as well as from the four cardinal points). The model-measurement comparison is based on hourly data from five locations within the square: from the center and from near the four bordering street facades of the rectangular square. Our initial results indicate that besides direct solar radiation, the temperatures of artificial surfaces (e.i. of building walls and pavements) strongly influences the human radiation balance: the increased temperature of surrounding surfaces increases the amount of emitted long-wave radiation and thus, reduces the amount a person is able to dissipate. Investigations like ours are necessary both for the advancement of our filed in general, and for the development of numerical models in particular. Models are simplifications of reality and thus they introduce a certain degree of idealization: trees are never as perfectly shaped or have a homogeneous crown transmissivity and leaf area index (LAI) in the reality, neither do surface parameters are as uniform as frequently assumed by models. All these differences influence model results to a certain degree. Therefore, the ideal outdoor thermal conditions that practitioners often plan for from behind their desks are likely to be worse in reality. Identifying the strengths and weaknesses of different models and revealing how they compare to reality is essential for both scientists and urban planners, since they all need to understand and acknowledge the limitations of the numerical approach.

12345 151 - 200 of 237
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • chicago-author-date
  • chicago-note-bibliography
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf