50Hertz, in collaboration with ENERTRAG SE, a prominent operator of renewable energy plants, has initiated a joint pilot project aimed at supplying reactive power through renewable energy sources near Bertikow in Brandenburg, Germany.
The project site at Bertikow boasts a combination of wind power and other renewable energy-based generation plants, which together possess an impressive capacity of over 500MW. These facilities are connected to the nearby 50Hertz substation.
In the future, these renewable energy plants will play a crucial role in providing reactive power, which is essential for maintaining voltage and ensuring grid stability, even during periods of low wind feed-in. Sufficient reactive power is fundamental to maintaining a stable power grid.
Reactive power facilitates the efficient transportation of electricity over extended distances. By compensating for voltage losses during transmission, it enables maximum active power delivery to consumers while safeguarding the reliable functioning of the grid.
Under current regulations, renewable energy plants are not obligated to deliver reactive power when their active power output is minimal (less than 10% of their total active power). This poses a challenge for power grid operators, as they must find alternative technical solutions to compensate for the required reactive power during such periods.
However, modern wind turbines possess the technical capability to provide reactive power, even in the absence of significant wind conditions.
The pilot project conducted by ENERTRAG and 50Hertz aims to assess the practical implementation and contractual framework for the retrieval of reactive power, with a view to potentially establishing a reactive power market in the future.
Ground-mounted photovoltaic systems can also contribute to the provision of reactive power through their inverters, particularly during nighttime when sunlight is unavailable.
Dirk Biermann, the Managing Director of Markets and System Operations at 50Hertz, emphasized the necessity of innovative solutions for reliable power grid operation in the context of the energy transition. He stated, “We at 50Hertz are exploring various possibilities. The continuous supply of reactive power from renewable energy plants represents a new technological and regulatory frontier. The knowledge we gather through this endeavor will also benefit grid operators at the distribution level, where the majority of renewable energy plants are directly connected.”
Thorsten Leske, the Head of the Electrical Grids Department at ENERTRAG, highlighted the increasing responsibility of renewable energy plants in providing system services that are currently fulfilled by conventional power plants. He stated, “In the pilot project, various renewable energy plants contribute reactive power to stabilize the transmission grid, even in the absence of wind. Simultaneously, this serves as an illustration of untapped technical possibilities within subordinate distribution grids. The next step involves establishing a market model for the provision of reactive power.”
As the pilot project progresses, the collaboration between 50Hertz and ENERTRAG seeks to unlock the potential for renewable energy plants to contribute significantly to voltage maintenance and grid stability, ultimately fostering a more reliable and sustainable energy infrastructure.