The company installed approximately 2.36 kilometers of copper cables insulated with cross-linked polyethylene (XLPE), with each meter weighing 41.1 kilograms and an external diameter of 156.2 millimeters. Three cable sections of roughly 590 meters each connect the autotransformer bank to the 525 kV sector, while three additional 200-meter sections link the reserve unit operating at 525 kV and 440 kV levels. The cables rest 1.1 meters below the top of their conduits.
The reinforcement increases energy interchange capacity between São Paulo and Paraná by 2 GW, equivalent to monthly consumption of approximately 8.3 million residential customers based on average usage of 174 kWh per consumer recorded in July 2026 by Empresa de Pesquisa Energética. The project forms part of Taesa’s Ananaí concession, awarded by ANEEL with operations scheduled through 2052, encompassing the 284-kilometer Ponta Grossa-Assis transmission line.
Taesa also installed a 1,500 MVA autotransformer bank designed to handle currents up to 2,566 amperes at 525 kV under normal and emergency conditions. The project adds approximately R$173 million to Taesa’s annual permitted revenue, costs ultimately embedded in electricity tariffs paid by grid users.
Company executives indicated the underground solution establishes a technical alternative for space-limited installations throughout the national interconnected system. Taesa operates 16,600 kilometers of transmission lines across 19 Brazilian states, positioning the firm to replicate the approach where aerial configurations prove impractical due to physical or operational constraints at substations handling growing renewable energy flows.
This article was curated and published as part of our South American energy market coverage.
