70-Percent Regulation

The 70 Percent Rule was a regulation in Germany under the Renewable Energy Sources Act (EEG) that affected the feed-in of electricity from photovoltaic systems. It stipulated that the feed-in capacity of a photovoltaic system with a nominal capacity of up to 25 kilowatt-peak (kWp) had to be limited to a maximum of 70 percent of the nominal capacity.

Background and Purpose

The goal of the regulation was to prevent overloading of the public power grid. Especially on sunny days, when electricity production from photovoltaic systems increases significantly, grid instability can occur. By limiting the feed-in capacity, it was ensured that the grid would not be overloaded and the security of supply would be maintained.

Impact and Criticism

The 70 percent rule meant that photovoltaic systems could not feed their full output into the grid. This resulted in reduced profitability for system operators. Furthermore, the regulation was criticized for being insufficiently flexible and for hindering the development of smart grids.

Current Status

The 70 percent rule has been abolished by an amendment to the EEG. Since then, photovoltaic systems are generally able to feed their full output into the grid. However, grid operators may still impose feed-in restrictions under certain conditions to ensure grid stability.

Conclusion

The 70 percent rule was a temporary but necessary measure to facilitate the integration of photovoltaics into the power grid. With the development of smart grids and the increasing use of storage systems, the need for such rigid regulations is gradually decreasing.

Additional Keywords: Photovoltaics, EEG, Feed-in Capacity, Grid Stability, Feed-in Management, Renewable Energy