Estonian national transmission system operator (TSO) Elering has launched procurements for the renovation of three 300-kilovolt overhead lines across Estonia and building of the synchronous condensers it will need to join the Continental European electrical grid.
The TSO is launching procurements for establishing synchronous condensers at its Viru, Püssi and Kiisa substations, according to a company press release. Synchronous condensers are used for controlling the frequency of a network. Their function is to add inertia to the system for moderating changes in frequency and thus allow the next measures to be applied in the frequency control process — in case of emergency, for example. Estonia's electrical system currently does not have any synchronous condensers.
Elering management board chairman Taavi Veskimägi said that the establishment of synchronous condensers and the renovation of the Estonia-Latvia overhead lines are condition for keeping Estonia's lights on when the Baltic countries join the Continental European frequency area.
"In the coming years, investments totaling an estimated €300 million will be made into the synchronous condensers and lines, allowing us not only to disconnect the power system from Russia, but to offer work to many companies in the energy sector," Veskimägi said.
Construction of the synchronous condensers and lines will begin early next year and run through 2025.
Last month, Elering launched a public procurement to find a builder for the renovation of the Tartu-Valmiera 330-kilovolt high-voltage line from Tartu to the Estonian-Latvian border. In the near future, procurements will also be launched for the renovation of the Balti-Tartu and Viru-Tsirguliina 330-kilovolt lines. In the course of these renovations, which are slated to run from 2021 through 2025, more than 50-year-old infrastructure will be replaced with more modern equipment. The renovation of these lines is necessary to reinforce transmission capacities in the north-south direction, a key precondition for joining the Continental European grid and frequency area.
To fund these investments, Elering will rely on European Union assistance and revenue from the sale of cross-border capacity, as a result of which investment costs will not need to be passed on to consumers in the form of network fees. Funding for the first stage of investments from the Connecting Europe Facility (CEF) has already been approved; the Estonian TSO obtained the maximum 75 percent co-financing level, with €141 million of the €187 million investment to be covered from the CEF. The application for funding the second stage is slated to be submitted to the European Commission soon together with Latvia, Lithuania and Poland.
According to plan, the Baltics' preparations for joining the Continental European frequency area must be complete by the end of 2025. Currently, the Baltic countries' electricity systems remain part of the united Russian electricity system, in which the Russian transmission network controls the frequency. The transition to the Continental European frequency area will provide the Baltics with total control over their electricity systems.
Editor: Aili Vahtla