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  • 1.
    Kovacs, Peter
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Hemlin, Olleper
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Persson, Jon
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Ollas, Patrik
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Larsson, David
    Femenias, Paula
    Chalmers University of Technology, Sweden.
    Thuvander, Liane
    Chalmers University of Technology, Sweden.
    Fahlen, Elsa
    Chalmers University of Technology, Sweden.
    Solceller som solavskärmning: Forskning, utveckling och demonstration2018Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report presents the implementation, results, discussion and conclusions of the project "Solar Shading in an Overall Perspective - From Energy Efficiency to Energy Production and from Product to Architecture". From 2015 to 2018, companies from the solar shading and solar PV industries, together with architects, researchers, contractors and property managers, have explored the area in order to increase interest, knowledge and acceptance for solar shading in various important target groups. A strong focus has been on the combination of solar cells and solar shadings in a product named electricity generating solar shading. Among the results is a literature summary and an experience feedback from eight installations, as well as a database of examples from about 70 solar-shading installations, most of which are built up of solar cells. A development effort in collaboration between solar shading- and solar PV companies has resulted in several new products that were evaluated in the project and now being demonstrated at RISE's office in Borås.

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  • 2.
    Kovacs, Peter
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Ollas, Patrik
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Hemlin, Olleper
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Regelmässiga förutsättningar för takrenoveringar och solcellsinstallationer – en litteratursammanställning2018Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Rapporten redogör för en tvådelad litteratursammanställning som dels sammanfattar incitament och regelmässiga hinder vid renovering av flerbostadshus, och dels redogör för de generella regelverk, policys och andra förutsättningar vid installationer av solcellsanläggningar. Den första delen är resultatet av litteratursökningar och intervjuer om tillgängliga stöd och reglerverk och den andra delen baseras enbart på litteratursökning. För aktörer på beställar- och leverantörssidan med intresse för takrenovering med solceller, syftar rapporten till att ge en bild av förutsättningarna i form av incitament och hinder.

    Den samlade bilden är att det pågår en snabb positiv utveckling kring incitament och regelverk specifikt för solceller och att även regelverk för energieffektivisering och miljöcertifiering kan motivera fastighetsägare till att ta ett sådant samlat grepp. Sammantaget utgör de styrande kraven – vid en renovering som klassas som en omfattande ändring – dock snarare ett hinder än en möjlighet för att genomföra de koncept som tagits fram i projektet.

    Denna rapport utgör ett komplement till projektrapporten för projektet ”Miljontak – takrenovering med solceller” (Energimyndighetens projektnummer: 41857-1) och finns tillgänglig via E2B2’s hemsida - http://www.e2b2.se/.

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  • 3.
    Leijon, Jennifer
    et al.
    Uppsala University, Sweden.
    Hagman, Jens
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Alfredsson, Hampus
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Ghaem Sigarchian, Sara
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation. RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Ollas, Patrik
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation.
    Aalhuizen, Christoffer
    Uppsala University, Sweden.
    Döhler, Jéssica
    Uppsala University, Sweden.
    Boström, Cecilia
    Uppsala University, Sweden.
    Thomas, Karin
    Uppsala University, Sweden.
    Airports with increased electrification – an ongoing project with case studies in Sweden2022Ingår i: 35th International Electric Vehicle Symposium and Exhibition (EVS35) Oslo, Norway, June 11-15, 2022, 2022Konferensbidrag (Övrigt vetenskapligt)
  • 4. Norberg, Ida
    et al.
    Pettersson, Ola
    RISE., SP – Sveriges Tekniska Forskningsinstitut, JTI Institutet för Jordbruks- och Miljöteknik.
    Gustavsson, Alf
    Kovacs, Peter
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi.
    Boork, Magdalena
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi.
    Ollas, Patrik
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi.
    Widen, Joakim
    Lingfors, David
    Marklund, Jesper
    Ingman, David
    Jältorp, Hans
    Solel i lantbruket - realiserbar potential och nya affärsmodeller2015Rapport (Övrigt vetenskapligt)
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  • 5.
    Ollas, Patrik
    Chalmers University of Technology, Sweden.
    Buildings' Transition to Active Nodes: Assessing the Viability of DC Distribution, PV and Battery Storage2024Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Historically, buildings have been passive nodes in the electric grid system with one-way power flows. However, with the recent market development of solar photovoltaic (PV) and stationary behind-the-meter battery storage systems, buildings are now transitioning to active nodes, offering bi-directional power flows. Various system topologies and modelling aspects are of interest for these active nodes and their viability. This thesis compares internal building direct current (DC) distribution with the conventional alternating current (AC) distribution for single-family and office buildings. For both building types, the geographical location is altered to examine the effect of PV and load correlation on the DC performance. The energy loss over a year and the loss distribution across various components are examined for three DC topologies, including one with constant power electronic converter (PEC) efficiencies, to quantify the loss discrepancy to experimentally derived PEC efficiency characteristics. Using constant efficiencies for a single-family building underestimates the annual losses by 34% (63 kWh/a). With load-dependant PEC efficiencies and without battery storage, DC operation shows no performance enhancements compared to AC. Depending on the studied case, DC operation results in loss savings, −16.3 to −43.6% with PV and battery.

    Two methods are proposed to reduce the grid-tied converter (GC) losses from partial load operation. One method—a modular GC design consisting of a smaller and a larger GC—is modelled for two cases: a single-family building and an office building, and presents an optimal GC size configuration of 15/85%. The loss savings relative to AC operations for a 15/85% configuration are 26% for the single-family building and 15–40% for the office. The savings depend on the office’s location and system design (PV and battery sizing). For the offices, the effect on DC loss savings is examined via a parametric sweep by varying PV and battery sizes, with resulting savings up to 40% (−12.8 MWh/a) compared to AC operation. The results highlight the effect of GC sizing on the DC performance, the effect of battery storage, and how the PV and load correlation affects the DC performance.

    Furthermore, a battery model is derived from experimental measurements of the cell’s current—resistance and open-circuit voltage (OCV)—state-of-charge (SOC) dependencies. The battery model is verified against the measured voltage with good compliance (RMSE<7 mV). Three representations—including the round trip efficiency approximation—are compared for annual battery system losses. The results indicate that the cell’s losses—making up 22–45% of losses for the examined case—and that the internal resistance’s current dependency is essential for an accurate representation. The loss discrepancy for the round trip approximation varies between −5% to 29%, relative to the experimentally derived representation, depending on the modelled battery size.

    The role of PV and battery storage for an airport micro grid is examined in a forward-looking case with electric aviation (EA) and electric vehicles (EVs). Seven scenarios are studied, including four with battery storage and different operation algorithms. One of the algorithms is a novel operation combining self-consumption (SC) and peak power shaving. Compared to the current situation, the techno-economic evaluation shows a significant increase in energy (89.4%) and power (+1 MW) demands from EA and EV. For the nominal battery price and peak power tariff (Ct), the novel operation shows the shortest Payback Period (PBP) of 4.8 years for the battery scenarios. With varying battery prices and peak power tariffs, the sensitivity analysis shows that Ct can significantly affect the PBP.

    Lastly, the effect of PV module operating temperature on performance is empirically evaluated and quantified for seven arrays from annual operation. For the Building–Applied PV (BAPV) c-Si modules, the elevated operating temperature adds 1% to the total losses and 2% for the c-Si Building–Integrated PV (BIPV). Examining the results of SC and self-sufficiency (SS) verifies the correlation between SC and power rating and introduces the correlation between SS and annual yield, considering the effect of system design, level of roof integration and PV cell type. For this case study, comparing two systems with and without battery storage shows the weekly variation in SS and SC and highlights the drawback of single-objective dispatch.

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  • 6.
    Ollas, Patrik
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser. Chalmers University of Technology, Sweden.
    Energy Savings Using a Direct Current Distribution Network in a PV and Battery Equipped Residential Building2020Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Energy from solar photovoltaic (PV) are generated as direct current (DC) and almost all of today’s electrical loads in residential buildings, household appliances and HVAC system (Heating Ventilation and Air-conditioning) are operated on DC. For a conventional alternating current (AC) distribution system this requires the need for multiple conversion steps before the final user-stage. By switching the distribution system to DC, conversion steps between AC to DC can be avoided and, in that way, losses are reduced. Including a battery storage–the system’s losses can be reduced further and the generated PV energy is even better utilised.

    This thesis investigates and quantifies the energy savings when using a direct current distribution topology in a residential building together with distributed energy generation from solar photovoltaic and a battery storage. Measured load and PV generation data for a single-family house situated in Borås, Sweden is used as a case study for the analysis. Detailed and dynamic models–based on laboratory measurements of the power electronic converters and the battery–are also used to more accurately reflect the system’s dynamic performance.

    In this study a dynamic representation of the battery’s losses is presented which is based on laboratory measurements of the resistance and current dependency for a single lithium-ion cell based on Lithium iron phosphate (LFP). A comparative study is made with two others, commonly used, loss representations and evaluated with regards to the complete system’s performance, using the PV and load data from the single-family house. Results show that a detailed battery representation is important for a correct loss prediction when modelling the interaction between loads, PV and the battery.

    Four DC system topologies are also modelled and compared to an equivalent AC topology using the experimental findings from the power electronic converters and the battery measurements. Results from the quasi-dynamic modelling show that the annual energy savings potential from the suggested DC topologies ranges between 1.9–5.6%. The DC topologies also increase the PV utilisation by up to 10 percentage points, by reducing the associated losses from the inverter and the battery conversion. Results also show that the grid-tied converter is the main loss contributor and when a constant grid-tied efficiency is used, the energy savings are overestimated.

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    Licentiatavhandling__OLLAS
  • 7.
    Ollas, Patrik
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser. Chalmers University of Technology, Sweden.
    Ghaem Sigarchian, Sara
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Alfredsson, Hampus
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Leijon, Jennifer
    Uppsala University, Sweden.
    Döhler, Jessica Santos
    Uppsala University, Sweden.
    Aalhuizen, Christoffer
    Uppsala University, Sweden.
    Thiringer, Torbjörn
    Chalmers University of Technology, Sweden.
    Thomas, Karin
    Uppsala University, Sweden.
    Evaluating the role of solar photovoltaic and battery storage in supporting electric aviation and vehicle infrastructure at Visby Airport2023Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 352, artikel-id 121946Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Following the societal electrification trend, airports face an inevitable transition of increased electric demand, driven by electric vehicles (EVs) and the potential rise of electric aviation (EA). For aviation, short-haul flights are first in line for fuel exchange to electrified transportation. This work studies the airport of Visby, Sweden and the effect on the electrical power system from EA and EV charging. It uses the measured airport load demand from one year’s operation and simulated EA and EV charging profiles. Solar photovoltaic (PV) and electrical battery energy storage systems (BESS) are modelled to analyse the potential techno-economical gains. The BESS charge and discharge control are modelled in four ways, including a novel multi-objective (MO) dispatch to combine self-consumption (SC) enhancement and peak power shaving. Each model scenario is compared for peak power shaving ability, SC rate and pay-back-period (PBP). The BESS controls are also evaluated for annual degradation and associated cost. The results show that the novel MO dispatch performs well for peak shaving and SC, effectively reducing the BESS’s idle periods. The MO dispatch also results in the battery controls’ lowest PBP (6.9 years) using the nominal economic parameters. Furthermore, a sensitivity analysis for the PBP shows that the peak power tariff significantly influences the PBP for BESS investment. 

  • 8.
    Ollas, Patrik
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Markusson, Caroline
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Eriksson, Jörgen
    EQUA Solutions, Sweden.
    Chen, Huijuan
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Lindahl, Markus
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Thiringer, Torbjörn
    Chalmers University of Technology, Sweden.
    Quasi-Dynamic Modelling of DC Operated Ground-Source Heat Pump2020Ingår i: SINTEF Proceedings; 5, Oslo, 2020, Vol. 5, s. 208-213Konferensbidrag (Refereegranskat)
    Abstract [en]

    The performance of a conventional ground-source heat pump (GSHP) has been measured in the laboratory with alternating current (AC) and direct current(DC) operation using the standardised points fromEN14511:2018. The results from these measurements have been used to modify a variable speed heat pump model in IDA Indoor Climate and Energy (ICE) and the annual performance of AC and DC operation have been simulated for an entire year's operation at two geographical locations in Sweden. Results show that the energy savings with DC operation from laboratory measurements span between 1.4{5.2% and when simulating the performance for an entire year's operation, the energy savings vary between 2.5{3.4%. Furthermore, the energy savings from the simulations have been compared to the bin method described in EN14825:2018.

  • 9.
    Ollas, Patrik
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Markusson, Caroline
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Persson, Jon
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Alfadel, Usama
    Soliga Energi, Sweden.
    Impact of Battery Sizing on Self-Consumption, Self-Sufficiency and PeakPower Demand for a Low Energy Single-Family House With PVProduction in Sweden2018Ingår i: 7th World Conference on Photovoltaic Energy Conversion (WCPEC-7), June 10-15, 2018, 2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper simulates the impact of battery sizingfor an actual nearly-zero energy (NZEB) single-family housewith solar PV located in Bor°as, Sweden. Simulations are done,using measurement data as an input, for three different batterydispatch algorithms with two different purposes; (i) peak powershaving and (ii) maximising system self-consumption (SC) andself-sufficiency (SS) of the solar PV. The results show that theoptimal battery storage size for this single-family house, givenits measured electrical loads and existing solar PV system isaround 7.2 kWh. System self-consumption and self-sufficiencyfrom generated solar PV increased with 24.3 percentage pointscompared to a reference case without battery. Furthermore,results show that increasing the battery size beyond 7.2 kWhonly results in minor performance gains.

  • 10.
    Ollas, Patrik
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Persson, Jon
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Markusson, Caroline
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Alfadel, Usama
    Soliga Energi, Sweden.
    Impact of Battery Sizing on Self-Consumption, Self-Sufficiency and Peak Power Demand for a Low Energy Single-Family House with PV Production in Sweden2018Ingår i: 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion, WCPEC 2018 - A Joint Conference of 45th IEEE PVSC, 28th PVSEC and 34th EU PVSEC, Institute of Electrical and Electronics Engineers Inc. , 2018, s. 618-623Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper simulates the impact of battery sizing for an actual nearly-zero energy (NZEB) single-family house with solar PV located in Boras, Sweden. Simulations are done,° using measurement data as an input, for three different battery dispatch algorithms with two different purposes; (i) peak power shaving and (ii) maximising system self-consumption (SC) and self-sufficiency (SS) of the solar PV. The results show that the optimal battery storage size for this single-family house, given its measured electrical loads and existing solar PV system is around 7.2 kWh. System self-consumption and self-sufficiency from generated solar PV increased with 24.3 percentage points compared to a reference case without battery. Furthermore, results show that increasing the battery size beyond 7.2 kWh only results in minor performance gains.

  • 11.
    Ollas, Patrik
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser. Chalmers University of Technology, Sweden.
    Thiringer, Torbjörn
    Chalmers University of Technology, Sweden.
    Chen, Hiujuan
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Markusson, Caroline
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Increased photovoltaic utilisation from direct current distribution: Quantification of geographical location impact2021Ingår i: Progress in Photovoltaics, ISSN 1062-7995, E-ISSN 1099-159X, Vol. 29, nr 7, s. 846-856Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, the performance of a direct current (DC) distribution system is modelled for a single-family residential building and compared with a conventional alternating current (AC) system to quantify the potential energy savings and gains in photovoltaic (PV) utilisation. The modelling is made for two different climates to quantify the impact of the geographical location. Results show that the system losses are reduced by 19–46% and the PV utilisation increased by 3.9–7.4% when using a DC distribution system compared to an AC equivalent, resulting in system efficiency gains in the range of 1.3–8.8%. Furthermore, it is shown that the geographical location has some effect on the system's performance and PV utilisation, but most importantly, the grid interaction is paramount for the performance of the DC topology. © 2021 The Authors.

  • 12.
    Ollas, Patrik
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Thiringer, Torbjörn
    Chalmers University of Technology, Sweden.
    Chen, Huijuan
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Markusson, Caroline
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Increased PV Utilisation from DC Distribution: Quantification of Geographical Impact2020Ingår i: EU PVSEC Conference Proceedings, 2020, s. 1432-1441Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, the performance of a direct current (DC) distribution system is modelled and compared fora single-family residential building with a conventional alternating current (AC) system to quantify the potential energy savings and gains in PV utilization. The modelling is also made for two different climates to quantify the impact of the geographical location. Results show that the system losses are reduced by 19-46% and the PV utilization increased by 3.9-7.4% when using a DC distribution system compared to an AC equivalent, resulting in system efficiency gains in the range of 1.3-8.8%. Furthermore, it is shown that the geographical location has some effect on the system's performance and PV utilization, but most importantly the grid interaction is paramount for the performance of the DC topology.

  • 13.
    Ollas, Patrik
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser. Chalmers University of Technology, Sweden.
    Thiringer, Torbjörn
    Chalmers University of Technology, Sweden.
    Persson, Mattias
    RISE Research Institutes of Sweden, Säkerhet och transport, Mätteknik.
    Markusson, Caroline
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Battery loss prediction using various loss models: A case study for a residential building2023Ingår i: Journal of Energy Storage, ISSN 2352-152X, E-ISSN 2352-1538, Vol. 70, artikel-id 108048Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work compares and quantifies the annual losses for three battery system loss representations in a case study for a residential building with solar photovoltaic (PV). Two loss representations consider the varying operating conditions and use the measured performance of battery power electronic converters (PECs) but differ in using either a constant or current-dependent internal battery cell resistance. The third representation is load-independent and uses a (fixed) round trip efficiency. The work uses sub-hourly measurements of the load and PV profiles and includes the results from varying PV and battery size combinations. The results reveal an inadequacy of using a constant battery internal resistance and quantify the annual loss discrepancy to −38.6%, compared to a case with current-dependent internal resistance. The results also show the flaw of modelling the battery system’s efficiency with a fixed round trip efficiency, with loss discrepancy variation between −5 to 17% depending on the scenario. Furthermore, the necessity of accounting for the cell’s loss is highlighted, and its dependence on converter loading is quantified.

    Ladda ner fulltext (pdf)
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  • 14.
    Ollas, Patrik
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser. Chalmers University of Technology, Sweden.
    Thiringer, Torbjörn
    Chalmers University of Technology, Sweden.
    Persson, Mattias
    RISE Research Institutes of Sweden, Säkerhet och transport, Mätteknik.
    Markusson, Caroline
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser.
    Energy Loss Savings Using Direct Current Distribution in a Residential Building with Solar Photovoltaic and Battery Storage2023Ingår i: Energies, E-ISSN 1996-1073, Vol. 16, nr 3, artikel-id 1131Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work presents a comparison of alternating current (AC) and direct current (DC) distribution systems for a residential building equipped with solar photovoltaic (PV) generation and battery storage. Using measured PV and load data from a residential building in Sweden, the study evaluated the annual losses, PV utilization, and energy savings of the two topologies. The analysis considered the load-dependent efficiency characteristics of power electronic converters (PECs) and battery storage to account for variations in operating conditions. The results show that DC distribution, coupled with PV generation and battery storage, offered significant loss savings due to lower conversion losses than the AC case. Assuming fixed efficiency for conversion gave a 34% yearly loss discrepancy compared with the case of implementing load-dependent losses. The results also highlight the effect on annual system losses of adding PV and battery storage of varying sizes. A yearly loss reduction of 15.8% was achieved with DC operation for the studied residential building when adding PV and battery storage. Additionally, the analysis of daily and seasonal variations in performance revealed under what circumstances DC could outperform AC and how the magnitude of the savings could vary with time. © 2023 by the authors.

  • 15.
    Ossman, Lisa
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Ruud, Svein
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Markusson, Caroline
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Kovacs, Peter
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Ollas, Patrik
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Wendin, Karin
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Lane, Anna-Lena
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Stensson, Sofia
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Haglund Stignor, Caroline
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Alsbjer, Markus
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Gustavsson, Lennart
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Förbrännings- och aerosolteknik.
    Nulägesanalys för satsning på NNE byggnader: slutrapport etapp 12012Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Det övergripande syftet med uppdraget är att få en detaljerad bild över byggnaders energiprestanda i Sverige. Den första etappen, förstudien, går ut på att beskriva metoden för hur denna analys ska göras. Som etapp 2 genomförs själva nulägesanalysen och slut¬ligen i etapp 3 analyseras resultat och slutsatser presenteras. I denna rapport redogörs för etapp 1, dvs metodbeskrivningen för nulägesanalysen. Nulägesanalysen ska senare kunna användas för att följa upp hur satsningar på Näranoll¬energibyggnader (NNE) påverkar energianvändningen i hela byggnadsbeståndet, inte bara i de faktiska demonstrationsprojekt som beviljas stöd och där uppföljning är betydligt enklare. Resultatet av nulägesanalysen, och den uppföljande analysen (planerad till 2015), ska i förlängningen kunna vara ett stöd när de nationella målnivåerna för näranollenergi-byggnader bestäms. I denna rapport redogörs för etapp 1, dvs metodbeskrivningen för nulägesanalysen. Rapporten beskriver vilka statistikkällor som finns idag samt en metod för hur dessa kan bidra till en mer detaljerad bild av byggnaders energiprestanda under ett valt referensår.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 16.
    Ruud, Svein
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Markusson, Caroline
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Nordén, Johan
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Hållbar Samhällsbyggnad, Byggnadsfysik och innemiljö.
    Karlsson, Henrik
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, SP – Sveriges Tekniska Forskningsinstitut / Byggnadsfysik och innemiljö (ETi ).
    Lindgren, Mikael
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Mätteknik, Kommunikation.
    Ollas, Patrik
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Energi och Bioekonomi, Klimatisering och installationsteknik.
    Belysningen väg från el till rumstemperatur2013Rapport (Refereegranskat)
    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 17.
    Sommerfeldt, Nelson
    et al.
    KTH Royal Institute of Technology, Sweden.
    Ollas, Patrik
    RISE - Research Institutes of Sweden, Samhällsbyggnad.
    Reverse engineering prototype solar pv/thermal collector properties from empirical data for use in TRNSYS Type 5602017Ingår i: ISES Solar World Congress 2017 - IEA SHC International Conference on Solar Heating and Cooling for Buildings and Industry 2017, Proceedings, International Solar Energy Society , 2017, s. 1121-1132Konferensbidrag (Refereegranskat)
    Abstract [en]

    Using the known physical characteristics of a prototype photovoltaic-thermal (PVT) collector components and raw test data from a prematurely terminated ISO 9806 test, the objective of this study is to reverse engineer a thermal resistance value for the heat exchanger assembly for use in the theoretical TRNSYS model Type 560. Modeling is done using both TRNSYS as well as commercial heat transfer software TAITherm. Performance is measured by the mean absolute error and correlation of the outlet temperature and thermal power, as well as the differences in total thermal energy generated. The results show a thermal resistance of 0.005 to 0.010 m2 K W-1 in TAITherm and 0.010 to 0.040 m2 K W-1 in Type 560. TAITherm gives better statistical indicators which is likely due to the inclusion of thermal mass in the model. The results have informed prototype development and can be used in further systems modeling. © 2017. The Authors.

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