Faster synchronization with the Continental European power system is achievable within a tight schedule

Today, the prime ministers of Estonia, Latvia, and Lithuania agreed to faster synchronization of the Baltic states' power grids with the Continental European grid and its frequency. From the perspective of Elering as the transmissioon system operator, faster synchronization is possible, but it requires taking into account the results of ongoing comprehensive risk analyses.

According to Taavi Veskimägi, the CEO of Elering, Estonia has managed to keep up with the necessary investments of the synchronization project despite a very challenging situation in the construction industry. "However, in accordance with the decision made by the heads of state to bring synchronization forward from the previously agreed deadline of the end of 2025, we are ready to make efforts and find ways to achieve this with minimal risks and costs for the consumer," Veskimägi said.

The effort towards faster synchronization is made possible by bringing forward the extensive reconstruction of the Estonian-Latvian interconnection. "For Estonian electricity consumers, the possibility of faster synchronization with acceptable risks is made possible by shifting the schedule of the reconstruction of the second Estonian-Latvian interconnection from October 2025 to the end of 2024," Veskimägi added. In addition to bringing forward the mentioned powerline, there are other important factors explained by ongoing studies that have to be considered when agreeing on an earlier deadline for desynchronization. Moreover, before synchronization, it is mandatory to conduct an isolated operation test of the Baltic power system.

The first Estonian-Latvian interconnection, consisting of two high-voltage lines passing through Estonia, is currently fully reconstructed and about to return to service. In 2020, in addition to the two interconnections being reconstructed, a brand new Estonian-Latvian interconnection was also completed.

In addition to the reconstruction of several important high-voltage lines, three synchronous condensers are required for synchronization. The Püssi synchronous condenser is ready and has been handed over to Elering by the main contractor, Siemens Energy. The most importnat equipment for the second synchronous condenser in Kiisa has been transported, and the construction of the third condenser at the Viru power plant has also begun.

 In addition to the infrastructure projects, upgrades to IT and control systems are also crucial. The most significant of these is the new energy management system SCADA with frequency control capabilities. With the upgrades, new capabilities will be added to the control center, such as frequency control, stability assessment, and improved system cyber security.