The efficient grid integration of renewables is discussed at the alumni seminar of the C3L wind and hydrogen programmes.
Around 70 alumni, lecturers and cooperation partners exchanged ideas at the annual network meeting of the wind studies and H2 further education programmes at the University of Oldenburg. The alumni seminar at ForWind focussed on the integration of green electricity into the grid. Before the panel discussion on the topic, Dr Matthias Stark from the German Renewable Energy Federation (BEE) presented the study on grid connection points, while Philip Goldkamp from Alterric explained how non-frequency-bound system services can be provided decentrally.
BEE expert Stark explained why grid expansion in Germany often proves to be a bottleneck in the expansion of renewable energies. Project planners of wind, PV or biomass systems often cannot find a free grid connection point - which can mean the end for smaller projects. There is a simple solution: if two paragraphs in the EEG were minimally adjusted, several renewable energy systems, storage systems or electrolysers could be connected to one point. In this case, more nominal power is connected than the grid connection point can actually transport. This so-called overbuilding would maximise the speed of the grid connection.
The study by BEE and the Fraunhofer IEE shows that even with an overbuilding of 150 or 250 per cent, surpluses rarely occur, meaning that electricity cannot be fed into the grid. The EEG currently requires that every connected system must be able to feed 100 per cent of its output into the grid at all times - which is usually not the case in practice. By sharing a grid connection point for electricity from wind and solar power, utilisation could be more than doubled in some cases, which would significantly reduce infrastructure costs.
Philip Goldkamp from Alterric explained how grid stability and quality can be ensured in an energy system dominated by renewable power plants. In addition to frequency maintenance, this increasingly involves non-frequency-related system services such as inertia, reactive power and black start capability. New system service markets are currently emerging for this purpose, which are organised by the grid operators via auctions. The elimination of conventional capacity requires the intelligent use of decentralised units - wind turbines themselves also make a significant contribution to these green ancillary services.
Dr Matthias Stark, Malte Neuendorff as a member of Alterric's management board, OFFIS CEO Prof. Dr Sebastian Lehnhoff, Dr Ricarda Schmidt-Scheele from the Institute of Social Sciences at the University of Oldenburg and Lars Bobzien from the Lower Saxony Ministry of Economic Affairs, Labour, Transport and Digitalisation took part in the panel discussion.
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