@inproceedings{24551,
  abstract     = {{Access to precise meteorological data is crucial to be able to plan and install renewable energy systems 
such as solar power plants and wind farms. In case of solar energy, knowledge of local irradiance and air temperature 
values is very important. For this, various methods can be used such as installing local weather stations or using 
meteorological data from different organizations such as Meteonorm or official Deutscher Wetterdienst (DWD). An 
alternative is to use satellite reanalysis datasets provided by organizations like the National Aeronautics and Space 
Administration (NASA) and European Centre for Medium-Range Weather Forecasts (ECMWF). In this paper the 
“Modern-Era Retrospective analysis for Research and Applications” dataset version 2 (MERRA-2) will be presented, 
and its performance will be evaluated by comparing it to locally measured datasets provided by Meteonorm and DWD. 
The analysis shows very high correlation between MERRA-2 and local measurements (correlation coefficients of 0.99) 
for monthly global irradiance and air temperature values. The results prove the suitability of MERRA-2 data for 
applications requiring long historical data. Moreover, availability of MERRA-2 for the whole world with an acceptable 
resolution makes it a very valuable dataset.}},
  author       = {{Khatibi, Arash and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 38th European Photovoltaic Solar Energy Conference and Exhibition (EUPVSEC 2021)}},
  isbn         = {{3-936338-78-7}},
  keywords     = {{Energy potential estimation, Photovoltaic, Solar radiation, Temperature measurement, Satellite data, Meteonorm, MERRA-2, DWD}},
  pages        = {{1141 -- 1147}},
  title        = {{{Comparison and Validation of Irradiance Data: Satellite Meteorological Dataset MERRA-2 vs. Meteonorm and German Weather Service (DWD)}}},
  doi          = {{10.4229/EUPVSEC20212021-5BV.4.11}},
  year         = {{2021}},
}

@inproceedings{24550,
  abstract     = {{Efficiencies and energy yields of microinverters available on the market during 2014‒2021 have been 
measured, compared, and ranked. Conversion efficiencies as a function of load have been measured indoors with high 
accuracy and ranked according to Euro- and CEC weightings. Energy yields have been measured outdoors via 
identical and calibrated crystalline silicon PV modules of 215 Wp (until 2020) and 360 Wp (starting 2021). Inverters 
with two inputs have been fed by two of those modules. DC input, AC power output and energy yield of each microinverter have been recorded by individual calibrated electricity meters. CEC and EU efficiency rankings have been 
computed and compared. 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 y = ax + b resulting in the actual yield, any module & inverter configuration can be 
characterized by just the coefficients a and b.}},
  author       = {{Krauter, Stefan and Bendfeld, Jörg}},
  booktitle    = {{Proceedings of the 38th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC 2021)}},
  isbn         = {{3-936338-78-7}},
  keywords     = {{AC-modules, Microinverter, Power Conditioning, Efficiency, Yield, PV module size, saturation, performance}},
  pages        = {{659 -- 663}},
  title        = {{{Module-Inverters (Microinverters): Influence of Module Size on Conversion Efficiencies and Energy Yields}}},
  doi          = {{10.4229/EUPVSEC20212021-4CO.3.4}},
  year         = {{2021}},
}

@inproceedings{24540,
  abstract     = {{With its growing population and industrialization, DREs, and solar technologies in particular, provide a 
sustainable means of bridging the current energy deficit in Africa, increasing supply reliability and meeting future 
demand. Data acquisition and data management systems allow real time monitoring and control of energy systems as 
well as performance analysis. However commercial data acquisition systems often have cost implications that are 
prohibitive for small PV systems and installations in developing countries.
In this paper, a multi-user, multi-purpose microgrid database system is designed and implemented. MAVOWATT 
270 power quality analyzers by GOSSEN METRAWATT, raspberry pi modules and sensors are used for measuring, 
recording and storing electrical and meteorological data in East Africa. Socio-economic data is also stored in the
database. The designed system employs open source software and hardware solutions which are best suited to 
developing regions like East Africa due to the lower cost implications.
The expected results promise a comprehensive database covering different electro-technical and socio-economic 
parameters useful for optimal design of microgrid systems.}},
  author       = {{Kakande, Josephine Nakato and Philipo, Godiana Hagile and Krauter, Stefan}},
  booktitle    = {{Proceedings of the 38th European Photovoltaic Solar Energy Conference and Exhibition (EUPVSEC 2021)}},
  isbn         = {{3-936338-78-7}},
  keywords     = {{Art-D, Afrika, Demand side management, MySQL, Raspberry pi, Data acquisition}},
  pages        = {{1505--1510}},
  title        = {{{Load Data Acquisition in Rural East Africa for the Layout of Microgrids and Demand–Side–Management Measures}}},
  doi          = {{10.4229/EUPVSEC20212021-6BV.5.38}},
  year         = {{2021}},
}