Eur. Phys. J. Plus (2014) 129: 20
https://doi.org/10.1140/epjp/i2014-14020-8

Regular Article

Electricity by intermittent sources: An analysis based on the German situation 2012

¹ Max-Planck Institut für Plasmaphysik, Wendelsteinstr. 1, 17489, Greifswald, Germany
² St. Petersburg State Polytechnical University, 29 Polytechnicheskaya st., 19525, St. Petersburg, Russia

^* e-mail: fritz.wagner@ipp.mpg.de

Received: 21 November 2013
Accepted: 7 January 2014
Published online: 3 February 2014

Abstract

The 2012 data of the German load, the on- and offshore and the photo-voltaic energy production are used and scaled to the limit of supplying the annual demand (100% case). The reference mix of the renewable energy (RE) forms is selected such that the remaining back-up energy is minimised. For the 100% case, the RE power installation has to be about 3 times the present peak load. The back-up system can be reduced by 12% in this case. The surplus energy corresponds to 26% of the demand. The back-up system and more so the grid must be able to cope with large power excursions. All components of the electricity supply system operate at low capacity factors. Large-scale storage can hardly be motivated by the effort to further reduce CO₂ emission. Demand-side management will intensify the present periods of high economic activities. Its rigorous implementation will expand the economic activities into the weekends. On the basis of a simple criterion, the increase of periods with negative electricity prices in Germany is assessed. It will be difficult with RE to meet the low CO₂ emission factors which characterise those European Countries which produce electricity mostly by nuclear and hydro power.