The over 300,000 PV systems in Bavaria with their intermittent energy output pose considerable challenges for grid operators, the Bavarian Energy and Water Association (VBEW) warned.
VBEW expects solar electricity in Bavaria to supply about 8% of the electricity consumed in Bavaria in 2011. This is already half of the 16% target for solar power, which the Bavarian energy concept aims to reach by 2021.
The more than 300,000 PV systems in Bavaria have a maximum output of almost 7,000 MW, VBEW points out. In winter, when PV systems often do not generate electricity, the Bavarian electricity demand amounts to approximately 12,000 MW. In periods of low demand on weekends and around noon, however, there is regularly more electricity generated by PV systems than consumed in Bavaria.
This is a great challenge for the Bavarian network operators, who are required by the Renewable Energy Sources Act (EEG) to connect renewable power plants to the grid with priority and to purchase, transmit and distribute the energy fed into the grids. The fact that grid and storage expansion cannot keep up with the expansion of solar power even aggravates the situation, VBEW says. Consequently, the association criticises the recent proposal by the German grid regulator, the Federal Network Agency, to lower the equity rates on the electricity and gas grids for the next regulation period, calling it counterproductive.
All participants in the electricity market are responsible for its functioning, VBEW points out. Hence, PV systems operators had to be prepared that their installations are temporarily taken control of (in the sense that they cannot feed into the grid) to ensure system stability, Detlef Fischer, managing director of VBEW says. The so-called feed-in management is regulated by Sections 11 and 12 EEG for renewable power plants with a capacity exceeding 100 KW. Under the revised EEG that will enter into force on 1 January 2012, more renewable power plants will be part of the feed-in management, as new provisions for PV systems will apply.