Chile’s National Electric Coordinator has submitted a proposal to the National Energy Commission (CNE) outlining 45 electricity transmission expansion projects, in compliance with Article 91 of the General Electricity Services Law.
The proposal includes 12 national transmission projects, representing an estimated investment of USD 343 million, and 33 zonal transmission initiatives amounting to USD 384 million. Together, these projects are designed to optimise transmission capacity, ensure operational efficiency, reduce supply risks and foster greater competition in Chile’s electricity market, which is fully interconnected from Arica in the far north to Chiloé in the south.
Key projects highlighted
Among the main works proposed are:
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Northern Chile: Installation of new transformers at the Nueva Lagunas, Kimal, Miraje and Jadresic substations to increase transformation capacity between 500 kV and 220 kV, supporting additional generation supply and facilitating market competition.
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Northern Interconnection: Sectioning of the 2×500 kV Los Changos–Kimal transmission line to strengthen the grid infrastructure in the Norte Grande region.
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Congestion relief: Capacity upgrade of the 2×220 kV Kimal–Crucero line, aimed at addressing forecast congestion and reinforcing power flows towards the Kimal substation.
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North–Central corridor: Construction of a new 2×220 kV Manuel Rodríguez–Agua Santa line to increase transmission capacity along the 220 kV corridor between these substations.
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Greater Santiago area: Expansion of the Polpaico, Lo Aguirre and Alto Jahuel substations with new transformers, alongside a capacity increase of the 2×220 kV Polpaico–Cerro Navia line, in order to maintain the N-1 security criterion and strengthen supply reliability in the Metropolitan Region.
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Supply security: Development of the new Lo Curro substation and a new 2×220 kV Lo Curro–Isabel Riquelme line through an additional 220 kV connection point.
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Additional reinforcement: Installation of a second 1×220 kV circuit on the Lo Aguirre–Alto Melipilla line, addressing expected congestion and reinforcing flows towards the Lo Aguirre substation.
The 33 zonal projects cover regions from Arica and Parinacota to Los Lagos. Their primary objective is to maintain system adequacy and improve the security of zonal networks, ensuring reliable electricity availability for the population across the entire country.
Strategic planning and industry engagement
These proposals complement the 2025 transmission expansion process, currently under review by the CNE, which included 46 initiatives. Once implemented, the new projects are expected to help the power system meet future challenges by delivering a robust and resilient transmission network, capable of supporting higher shares of renewable energy, grid integration and long-term security of supply.
Each project was assessed using advanced electrical modelling tools to evaluate its impact on system adequacy, security and least-cost operation, with the overarching goal of contributing to lower electricity prices.
The recommendations are the result of a collaborative process led by the National Electric Coordinator, involving industry stakeholders throughout 2025. This process included technical workshops and working groups held between May and September, where system diagnostics and expansion alternatives were discussed. The final document also addresses 107 comments submitted by 12 companies on the diagnostic report, as well as 70 observations from 16 companies on the preliminary version of the proposal released in recent weeks.
