The $435m project, which is now operating as an integral part of SDG&E’s electric transmission system, is expected to boost reliability and serve as interconnection point for renewable resources.

The project comprises a new substation in the East County community of Jacumba, an upgraded substation in Boulevard and a 14-mile transmission line connecting the two substations.

Designed to enhance electric reliability in the region, the ECO Substation project will support the delivery of renewable wind and solar energy to SDG&E customers.

SDG&E electric transmission and system engineering vice president David Geier said: "The ECO Substation project is a vital reliability addition to our local transmission system and will improve our service to our customers in the eastern part of our county.

"This project will also help in meeting California’s aggressive renewable energy goals by facilitating the development of renewable energy in the region."