Geographical and temporal description of solar feed-in

Project state
Zu sehen ist die Nahaufnahme eines Solarparks.
Solar power systems are an important pillar of the future energy mix. Aside from installations on rooftops, large solar farms as shown in the picture are being used as well. | Image: Rainer Sturm,

Due to the expansion of renewable energy, transmission systems and distribution grids are more heavily loaded than they were in the past. Smart distribution grids and interfaces are required for a sensible utilisation of the energy fed into the grid, in particular for an optimal integration of storage solutions. This will require reliable studies that allow for a geographic analysis based on real operational data, and thus an accurate understanding of the energy flows under different boundary conditions. This is the core objective of the research project GEOWISOL.

Eine Deutschlandkarte mit einer beispielhaften Übersicht der normierten Solareinspeisung aufgeteilt nach zweistelligen Postleitzahl-Bereichen.
Example of normalised solar power feed-in in Germany divided into two-digit postal code areas.

The researchers are realising their tasks by studying the geographically distributed electricity generation from solar and wind farms based on recorded operating data of postal code areas in Germany. A second aspect of wind and solar generation is the wide geographic dispersion of generation systems. This causes technically identical systems to generate differing amounts of energy at different times. In addition to onshore energy generation, there are offshore wind farms located in the exclusive economic zones of the North and Baltic Seas. These influences will be studied in the planned project. The foundation of the study are the data of around 2,000 wind turbines from about 260 wind farms or locations, as well as thousands of photovoltaic systems in the form of time series. The resolution of these time series is ten minutes for wind turbines, and 15 minutes for photovoltaics, available for two and three whole years. In addition to studying the correlation, or anti-correlation, between the distributed feed-in types, a comparison will be made with the load profile of national electricity consumption.

The first result of the project will be the time series of regional power generation from wind turbines and solar power systems throughout the entire federal territory. They provide information on:•    The correlation, or anti-correlation, between wind and solar power generation

  • The required cross-border electricity exchange capacities  
  • Studies on the storage capacities required to lower the exchange capacity or balancing power in Germany
  • The level of necessary “overproduction” from RE installations
  • The extent of necessary feed-in intervention
  • The economic impact of avoided feed-in (loss of revenue).

The project partners are the Bremen Institute for Metrology, Automation and Quality Science of the University of Bremen, and Deutsche WindGuard GmbH.

Project duration

09/2015 - 11/2016


Volker Renken
Project co-ordinator
Universität Bremen – BIMAQ
Linzer Str. 13
28359 Bremen

+49 421 218-64626
+49 421 218-64670

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