San Diego Gas & Electric (SDG&E) says it has completed and put into service the Sunrise Powerlink, a 500 kV transmission line linking San Diego to the Imperial Valley, one of the most renewable-energy-rich regions in California.
The transmission line will initially be capable of bringing 800 MW of additional imported power – including renewable energy – into San Diego, and will eventually carry 1 GW of power.
In the near future, the Sunrise Powerlink will deliver a significant amount of wind and solar power to San Diego. Over the past three years, SDG&E has signed eight renewable energy agreements for more than 1 GW of wind and solar power from projects in Imperial County, and that renewable energy will be transmitted across the Sunrise Powerlink.
The transmission project consists of more than 110 miles of overhead 500 kV and 230 kV transmission towers and conductor, 6.2 miles of underground 230 kV cable, and a 40-acre, 500 kV transmission substation.
SDG&E and the California Independent System Operator Corp. say the transmission line is one of the important mitigation measures that will help maintain electric reliability during heat waves without power from the San Onofre Nuclear Generating Station.
The completion of the nearly $1.9 billion project culminates a rigorous, five-year-long environmental review and permitting process and 18 months of construction that encompassed both overhead and underground technology, as well as different climates and rough, remote terrain, SDG&E explains.
"The Sunrise Powerlink, which now provides the pathway for local renewable energy projects, enables us to develop Imperial County's abundant renewable energy resources while also preserving our natural resources and native habitat," says Imperial County Board Supervisor Gary Wyatt.