@inproceedings{56174,
  author       = {{Krauter, Stefan and Bendfeld, Jörg}},
  booktitle    = {{Proceedings of the 41st European Photovoltaic Solar Energy Conference}},
  location     = {{Wien}},
  title        = {{{PV Microinverters: Balcony Power Plants, Latest Efficiency Rankings, Yield Calculation for Overpowered Mini PV Systems}}},
  year         = {{2024}},
}

@inproceedings{56652,
  author       = {{Möller, Marius Claus and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 41st European Photovoltaic Solar Energy Conference}},
  location     = {{Austria Center Vienna}},
  title        = {{{Cost Analysis for a Small-Scale Hybrid, Hydrogen-Based PV Energy System}}},
  year         = {{2024}},
}

@phdthesis{56651,
  author       = {{Philipo, Godiana Hagile}},
  title        = {{{Analysis and Demand Side Management of East African Rural Microgrids: Modelling and Experimental study}}},
  year         = {{2024}},
}

@article{56929,
  abstract     = {{<jats:p>The market for microinverters is growing, especially in Europe. Driven by rising electricity prices and an easing in legislation since 2024, the number of mini-photovoltaic energy systems (mini-PVs) being installed is increasing substantially. Indoor and outdoor studies of microinverters have been carried out at Paderborn University since 2014. In the indoor lab, conversion efficiencies as a function of load have been measured with high accuracy and ranked according to Euro and CEC weightings; the latest rankings from 2024 are included in this paper. In the outdoor lab, energy yields have been measured using identical and calibrated crystalline silicon PV modules; until 2020, measurements were carried out using 215 Wp modules. Because of increasing PV module power ratings, 360 Wp modules were used from 2020 until 2024. In 2024, the test modules were upgraded to 410 Wp modules, taking into account the increase from 600 W to 800 W of inverter power limits, which is suitable for simplified operation permission (“plug-in”) in many European countries within a homogenised legislation area for such mini-photovoltaic energy systems or “balcony power plants”. This legislation for simplified operation also covers overpowered mini-plants, although the maximum AC output remains limited to 800 W. Presently, yield assessments are being carried out in the outdoor lab, which will take at least a year to be valid and comparable. Kits consisting of PV modules, inverters, and mounting systems are also being evaluated. Yield rankings sometimes differ from efficiency rankings due to the use of different MPPT algorithms with different MPP approach speeds and accuracies. To accelerate yield assessment, we developed a novel, simple formula to determine energy yield for any module and inverter configuration, including overpowered systems. This is a linear approach, determined by just two coefficients, a and b, which are given for several inverters. To reduce costs, inverters will be integrated into the module frame or the module terminal box in the future.</jats:p>}},
  author       = {{Krauter, Stefan and Bendfeld, Jörg}},
  issn         = {{1996-1073}},
  journal      = {{Energies}},
  number       = {{22}},
  publisher    = {{MDPI AG}},
  title        = {{{Efficiency Ranking of Photovoltaic Microinverters and Energy Yield Estimations for Photovoltaic Balcony Power Plants}}},
  doi          = {{10.3390/en17225551}},
  volume       = {{17}},
  year         = {{2024}},
}

@book{55482,
  abstract     = {{https://www.akkudoktor.net/2024/07/24/kostenloses-balkonsolar-buch/}},
  author       = {{Schmitz, Andreas and Ofenheusle, Christian and Müller, Sebastian and Krauter, Stefan}},
  isbn         = {{979-8328709576}},
  publisher    = {{Eigenverlag}},
  title        = {{{Balkonkraftwerke für alle: Der Leitfaden für die Energiewende zum Selbermachen}}},
  year         = {{2024}},
}

@article{58543,
  abstract     = {{<jats:p>This work analyses load profiles for East African microgrids, and then investigates the integration of electric two-wheelers and portable storage into a solar PV with battery microgrid in Uganda, East Africa. By introducing e-mobility and portable storage, demand side management strategic load growth can thus be achieved and electricity access can be expanded. Battery degradation is also considered. The results showed a 98.5% reduction in PV energy curtailment and a 57% reduction in the levelized cost of energy (LCOE) from 0.808 USD/kWh to 0.350 USD/kWh when the electric two-wheeler and portable storage loads were introduced. Such reductions are important enablers of financial viability and sustainability of microgrids. It is possible to avoid emissions of up to 73.27 tons of CO2/year with the proposed e-bikes, and an average of 160 customers could be served annually as off-microgrid consumers without requiring an investment in additional distribution infrastructure. Annual revenue could be increased by 135% by incorporating the additional loads. Sensitivity analyses were conducted by varying component costs, the battery lifetime, the interest rate, and the priority weighting of the additional loads. The battery costs were found to be a major contributor to lifecycle costs (LCC) and also have a big impact on the LCOE. The interest rate significantly affects the LCC as well.</jats:p>}},
  author       = {{Kakande, Josephine Nakato and Philipo, Godiana Hagile and Krauter, Stefan}},
  issn         = {{2673-9941}},
  journal      = {{Solar}},
  number       = {{4}},
  pages        = {{694--727}},
  publisher    = {{MDPI AG}},
  title        = {{{Optimized E-Mobility and Portable Storage Integration in an Isolated Rural Solar Microgrid in Uganda}}},
  doi          = {{10.3390/solar4040033}},
  volume       = {{4}},
  year         = {{2024}},
}

@article{35428,
  abstract     = {{This paper presents a model of an energy system for a private household extended by a lifetime prognosis. The energy system was designed for fully covering the year-round energy demand of a private household on the basis of electricity generated by a photovoltaic (PV) system, using a hybrid energy storage system consisting of a hydrogen unit and a lithium-ion battery. Hydrogen is produced with a Proton Exchange Membrane (PEM) electrolyser by PV surplus during the summer months and then stored in a hydrogen tank. Mainly during winter, in terms of lack of PV energy, the hydrogen is converted back into electricity and heat by a fuel cell. The model was created in Matlab/Simulink and is based on real input data. Heat demand was also taken into account and is covered by a heat pump. The simulation period is a full year to account for the seasonality of energy production and demand. Due to high initial costs, the longevity of such an energy system is of vital interest. Therefore, this model was extended by a lifetime prediction in order to optimize the dimensioning with the aim of lifetime extension of a hydrogen-based energy system. Lifetime influencing factors were identified on the basis of a literature review and were integrated in the model. An extensive parameter study was performed to evaluate different dimensionings regarding the energy balance and the lifetime of the three components, electrolyser, fuel cell and lithium-ion battery. The results demonstrate the benefits of a holistic modelling approach and enable a design optimization regarding the use of resources, lifetime and self-sufficiency of the system}},
  author       = {{Möller, Marius Claus and Krauter, Stefan}},
  issn         = {{2673-9941}},
  journal      = {{Solar}},
  number       = {{1}},
  pages        = {{25--48}},
  publisher    = {{MDPI AG}},
  title        = {{{Dimensioning and Lifetime Prediction Model for a Hybrid, Hydrogen-Based Household PV Energy System Using Matlab/Simulink}}},
  doi          = {{10.3390/solar3010003}},
  volume       = {{3}},
  year         = {{2023}},
}

@inproceedings{47118,
  author       = {{Möller, Marius Claus and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 40th European Photovoltaik Solar Energy Conference and Exhibition}},
  location     = {{Lisbon, Portugal}},
  title        = {{{Evaluation of the Influence of Different Energy Usage Behavior, Component Dimensionings and PV Orientations on the Suitability and Lifetime of a Hybrid, Hydrogen-Based PV Energy System for a Private Household}}},
  year         = {{2023}},
}

@inproceedings{47119,
  author       = {{Krauter, Stefan and Bendfeld, Jörg}},
  booktitle    = {{Proceedings of the 40th European Photovoltaik Solar Energy Conference and Exhibition}},
  location     = {{Lisbon, Portugal}},
  title        = {{{PV Microinverters: Latest Efficiency Rankings, Energy Yield Assessments, Firmware Issues}}},
  year         = {{2023}},
}

@inproceedings{48532,
  author       = {{Philipo, Godiana Hagile and Kakande, Josephine Nakato and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 2023 IEEE PES/IAS PowerAfrica Conference}},
  location     = {{Marrakech, Morocco}},
  title        = {{{Combined Economic and Emission Dispatch of a Microgrid Considering Multiple Generators}}},
  year         = {{2023}},
}

@inproceedings{48533,
  author       = {{Kakande, Josephine Nakato and Philipo, Godiana Hagile and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 2023 IEEE PES/IAS PowerAfrica Conference}},
  location     = {{Marrakech, Morocco}},
  title        = {{{Demand side management potential of refrigeration appliances}}},
  year         = {{2023}},
}

@inproceedings{48531,
  author       = {{Philipo, Godiana Hagile and Kakande, Josephine Nakato and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 2023 IEEE AFRICON,  Nairobi, Kenya}},
  location     = {{ Nairobi, Kenya}},
  title        = {{{Demand-Side-Management for Optimal dispatch of an Isolated Solar Microgrid}}},
  year         = {{2023}},
}

@inproceedings{55449,
  author       = {{Mwammenywa, Ibrahim and Hilleringmann, Ulrich}},
  booktitle    = {{2023 IEEE AFRICON}},
  publisher    = {{IEEE}},
  title        = {{{Analysis of Electricity Power Generation and Load Profiles in Solar PV Microgrids in Rural Villages of East Africa: Case of Mpale Village in Tanzania}}},
  doi          = {{10.1109/africon55910.2023.10293635}},
  year         = {{2023}},
}

@book{55450,
  abstract     = {{<jats:p>Globalisierung, Digitalisierung, Klimawandel, Migrationsbewegungen und Pandemie gestalten nicht nur unseren Alltag, sondern auch die Wissenschaft neu. Angesichts dieser gesellschaftlich tiefgreifenden Veränderungen werden Grenzen und ihre Überwindung zu immer zentraleren Herausforderungen, auch für die pädagogischen Forschungsfelder. Der Band versammelt vielfältige Beitrage zum Thema Entgrenzungen und richtet dabei den Blick auf Ent- und Begrenzung in ihrer Bedeutung für Bildung, Erziehung und Sozialisation.</jats:p>}},
  editor       = {{Heinemann, Alisha and Karakaşoğlu, Yasemin and Linnemann, Tobias and Rose, Nadine and Sturm, Tanja}},
  isbn         = {{9783847427506}},
  publisher    = {{Verlag Barbara Budrich}},
  title        = {{{Entgrenzungen. Beiträge zum 28. Kongress der Deutschen Gesellschaft für Erziehungswissenschaft}}},
  doi          = {{10.3224/84742750}},
  year         = {{2023}},
}

@article{59457,
  abstract     = {{<jats:p>The realization of a carbon-neutral civilization, which has been set as a goal for the coming decades, goes directly hand-in-hand with the need for an energy system based on renewable energies (REs). Due to the strong weather-related, daily, and seasonal fluctuations in supply of REs, suitable energy storage devices must be included for such energy systems. For this purpose, an energy system model featuring hybrid energy storage consisting of a hydrogen unit (for long-term storage) and a lithium-ion storage device (for short-term storage) was developed. With a proper design, such a system can ensure a year-round energy supply by using electricity generated by photovoltaics (PVs). In the energy system that was investigated, hydrogen (H2) was produced by using an electrolyser (ELY) with a PV surplus during the summer months and then stored in an H2 tank. During the winter, due to the lack of PV power, the H2 is converted back into electricity and heat by a fuel cell (FC). While the components of such a system are expensive, a resource- and cost-efficient layout is important. For this purpose, a Matlab/Simulink model that enabled an energy balance analysis and a component lifetime forecast was developed. With this model, the results of extensive parameter studies allowed an optimized system layout to be created for specific applications. The parameter studies covered different focal points. Several ELY and FC layouts, different load characteristics, different system scales, different weather conditions, and different load levels—especially in winter with variations in heating demand—were investigated.</jats:p>}},
  author       = {{Möller, Marius Claus and Krauter, Stefan}},
  issn         = {{2673-4141}},
  journal      = {{Hydrogen}},
  number       = {{3}},
  pages        = {{408--433}},
  publisher    = {{MDPI AG}},
  title        = {{{Investigation of Different Load Characteristics, Component Dimensioning, and System Scaling for the Optimized Design of a Hybrid Hydrogen-Based PV Energy System}}},
  doi          = {{10.3390/hydrogen4030028}},
  volume       = {{4}},
  year         = {{2023}},
}

@inproceedings{32334,
  abstract     = {{The market for microinverters is growing, especially in Europe. Driven by the strongly rising prices for electricity, many small photovoltaic energy systems are being installed. Since monitoring for these plants is often quite costly, their yields are often not logged. Since 2014, microinverters have been studied at the University of Paderborn. The investigations are divided into indoor and outdoor tests. In the indoor area conversion efficiencies as a function of load have been measured with high accuracy and ranked according to Euro- and CEC weightings. In the outdoor laboratory, the behavior in the real world is tested. Energy yields have been measured outdoors via identical and calibrated crystalline silicon PV modules. Here, the investigations were carried out with modules of the power of 215 Wp until the year 2020. Because of the increasing module power nowadays, modules with an output of 360 Wp are now being used. To assess the influence of PV module size, two extremes have been investigated: A rather small module with 215 Wp - as it has been used 10 years ago, and a brand-new module (2021) offering 360 Wp. Both types of modules contain 60 solar cells in series connection. Appling the low-power modules, the challenge for the different micro-inverters has been during weak-light conditions, using the high-power modules, some inverters temporarily reach their power limits and yield is reduced. A method using a reference configuration of inverter & module and a linear equation resulting in the actual yield, any module & inverter configuration can be characterized by just the two coefficients.}},
  author       = {{Krauter, Stefan and Bendfeld, Jörg and Möller, Marius Claus}},
  booktitle    = {{Proceedings of the 49th IEEE Photovoltaic Specialists Conference}},
  location     = {{Philadelphia, PA, USA}},
  title        = {{{Microinverter testing update using high power modules: Efficiency, yield, and conformity to a new ”estimation formula” for variation of PV panel size}}},
  year         = {{2022}},
}

@inproceedings{32333,
  abstract     = {{This paper provides a hybrid energy system model created in Matlab/Simulink which is based on photovoltaics as its main energy source. The model includes a hybrid energy storage which consists of a short-term lithium-ion battery and hydrogen as long-term storage to ensure autonomy even during periods of low PV production (e.g., in winter). The sectors heat and electricity are coupled by using the waste-heat generated by production and reconversion of hydrogen through an electrolyser respectively a fuel cell. A heat pump has been considered to cover the residual heat demand (for well insulated homes). Within this paper a model of the space heating system as well as the hot water heating system is presented. The model is designed for the simulation and analysis of a whole year energy flow by using a time series of loads, weather and heat profiles as input. Moreover, results of the energy balance within the energy system by simulation of a complete year by varying the orientation (elevation and azimuth) of the PV system and the component sizing, such as the lithium-ion battery capacity, are presented. It turned out that a high amount of heating energy can be saved by using the waste heat generated by the electrolyser and the fuel cell. The model is well suited for the analysis of the effects of different component dimensionings in a hydrogen-based energy system via the overall energy balance within the residential sector.}},
  author       = {{Möller, Marius Claus and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 49th IEEE Photovoltaic Specialists Conference}},
  location     = {{Philadelphia, PA, USA}},
  title        = {{{Model of a Self-Sufficient PV Home using a Hybrid Storage System based on Li-Ion Batteries and Hydrogen Storage with Waste Heat Utilization }}},
  year         = {{2022}},
}

@article{30262,
  abstract     = {{In this paper, a model of a hybrid, hydrogen-based energy system for a household which includes the heating sector is presended. With such an energy system it's possible to enable energy autarky over a whole year based on solar energy. The scope of this study was to present a verified hybrid energy system model created in Simulink which can be used to prospectively size future similar energy systems where hydrogen in combination with a li-ion battery shall be used as energy storage type.}},
  author       = {{Möller, Marius Claus and Krauter, Stefan}},
  issn         = {{1996-1073}},
  journal      = {{Energies / Special Issue "Sustainable Energy Concepts for Energy Transition"}},
  publisher    = {{MDPI / Basel, Switzerland}},
  title        = {{{Hybrid Energy System Model in Matlab/Simulink based on Solar Energy, Lithium-Ion Battery and Hydrogen}}},
  doi          = {{10.3390/en15062201}},
  volume       = {{15 (6), 2201}},
  year         = {{2022}},
}

@inproceedings{34155,
  author       = {{Krauter, Stefan and Bendfeld, Jörg}},
  booktitle    = {{Proceedings of the 8th World Conference on Photovoltaik Energy Conversion}},
  location     = {{Milano / Italy}},
  title        = {{{Microinverter PV Systems: New Efficiency Rankings and Formula for Energy Yield Assessment for any PV Panel Size at different Microinverter types}}},
  year         = {{2022}},
}

@inproceedings{34156,
  author       = {{Kakande, Josephine Nakato and Philipo, Godiana Hagile and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 8th World Conference on Photovoltaik Energy Conversion}},
  location     = {{Milano / Italy}},
  title        = {{{Optimal Design of a Semi Grid-Connected PV System for a Site in Lwak, Kenya Using HOMER}}},
  year         = {{2022}},
}