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Time in the Sun: The Challenge of High PV Penetration in the German Electric Grid

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Energy supply systems are facing significant changes in many countries around the globe. A good example of such a transformation is the German power system, where renewable energy sources (RESs) are now contributing 25% of the power needed to meet electricity demand, compared with 5% only 20 years ago. In particular, photovoltaic (PV) systems have been skyrocketing over the last couple of years. As of September 2012, about 1.2 million PV systems were installed, with a total installed peak capacity of more than 31 GWp. During some hours of 2012, PV already contributed about 40% of the peak power demand. It seems that Germany is well on the way to sourcing a major portion of its energy needs from solar installations. PV must therefore provide a full range of services to system operators so as to replace services provided by conventional bulk power plants.
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... Various renewable energy sources (RES) can be connected to the microgrid such as solar panels, wind turbines, etc. With the advancement of technology, the diminishing supply of conventional power sources and many environmental and socio-economic factors have raised RES penetration in the microgrid [1][2][3][4]. Increased renewable energy in the microgrid provides numerous benefits, like increased local power availability, low-cost, clean energy, increased reliability and resilience, reduced grid congestion and peak loads, etc. However, the intermittent nature of RES creates power fluctuations and large variations in the voltage profile. ...
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Progress in Photovoltaics: Research and Applications, 27th EU PVSEC, special issue, frankfurt, germany, 2012. t. stetz, f. marten, and m. Braun, "improved low voltage grid-integration of photovoltaic systems in germany
  • Kraiczy
  • S Braun
  • Schmidt
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