Southern California Edison's (SCE's) support of California's clean energy goals hit a tangible milestone in May with the completion of upgrades to the SCE's West of Devers transmission lines. The project increases transmission capacity necessary to bring renewable generation — more than 7000 MW of renewable and battery energy storage resources in the coming years — from desert areas in the eastern part of California to the population centers of the Inland Empire and San Gabriel Valley.
"Completing the West of Devers Project is another giant step in our ability to deliver clean energy throughout our service area," said Kevin Payne, SCE president and CEO. "While distributed energy resources (DERs) like rooftop solar and battery energy storage will contribute to decarbonizing our electric infrastructure, large-scale generation and reliable delivery of renewable energy will be vital to achieve California's ambitious climate goals."
The project consisted of removing and replacing conductors and supporting structures of four separate circuits of 220-kV transmission lines through the existing 48-mile corridor from the Devers substation near Palm Springs to the Vista and San Bernardino substations in Grand Terrace and San Bernardino, respectively — about 200 miles of power lines. It triples the capacity of power delivery from 1600 MW to 4800 MW, which helps with system reliability into the Southern California population centers during peak summer demand. It took many years of planning, siting, public engagement, licensing, and construction to bring this project to fruition.
As part of the West of Devers Project, the SCE entered into a transaction with Morongo Transmission for it to invest in the project, which allowed the SCE to build the project across the Morongo Indian Reservation. The total cost of the project was US$740 million, with Morongo Transmission expected to invest US$400 million later this year (upon regulatory approval).
The SCE applied in 2013 to the Federal Energy Regulatory Commission and the California Public Utilities Commission requesting approvals to build the project. In 2017, the company received all necessary environmental permits and regulatory approvals to start construction, which began in early 2018. West of Devers went into service about five months before its originally projected timeframe.
"The ability to achieve commercial operation ahead of schedule is a testament to the commitment and dedication of all the project team members and the multitude of stakeholders who contributed to the project's success," said Chuck Adamson, principal manager of Major Construction for the SCE. "With the complexities that accompany a modern-day transmission project, this achievement cannot be overstated."
The SCE built the project in an environmentally beneficial way by rebuilding within a corridor containing existing transmission lines, despite the unique operational challenges of this approach. The project spans several Riverside and San Bernardino communities, including Banning, Beaumont, Calimesa, Colton, Grand Terrace, Loma Linda, Redlands, and other unincorporated areas of Riverside and San Bernardino counties. The corridor also passes through the reservation trust land of the Morongo Band of Mission Indians, a key partner with the SCE in its bid to obtain environmental permits.
