The California Independent System Operator Corporation (California ISO) Board of Governors has unanimously approved the Sunrise/Greenpath transmission project proposed jointly by San Diego Gas and Electric (SDG&E), Imperial Irrigation District (IID) and Citizens Energy. The project will provide a vital "electricity on ramp" from the southeastern corner of the state to San Diego and the rest of the California grid. The combination 500-kV/230-kV transmission link will also provide access to hundreds of megawatts in renewable generation, bringing much-needed green power onto the grid.
In approving the Sunrise/Greenpath project, the California ISO Board found it will lower costs for San Diego consumers and provide significant reliability benefits to San Diego, Imperial Valley and Southern California in general by bolstering a weak link in the transmission network. The Board also found the Sunrise/Greenpath project will help deliver hundreds of megawatts of solar, geothermal and wind power proposed for development in Imperial County. Getting the green power on the grid will help utilities meet the state's requirement to procure or generate 20 % of their power supply from renewable resources by the year 2010. By adding a third major transmission corridor in the San Diego area, the line will improve the overall reliability of the region’s energy network, according to SDG&E officials.
“Today, SDG&E has only two major interconnections with the statewide power grid, because San Diego is an energy cul-de-sac,” said Debra L. Reed, president and chief operating officer of SDG&E. “Our customers expect us to deliver reliable service – in the midst of hot weather or wildfires – without worrying about the chance of a blackout. The Sunrise Powerlink will give us more transmission system flexibility in the future to keep delivering power under extreme conditions, as well as gain greater access to clean, renewable and affordable energy. ”
The Cal-ISO has forecast an electricity shortfall for the San Diego region as soon as 2010, the target date for the Sunrise Powerlink to be put into service. The line is designed to deliver 1,000 MW – enough electricity to supply about 650,000 homes.
"As an independent grid planner, the California ISO takes a critical eye to every transmission project proposed -- making sure the investment is sound and responsible," said ISO Board Chair Mason Willrich. "We agree with our staff assessment that Sunrise/Greenpath provides a comprehensive solution that will strengthen the grid, provide economic and reliability benefits as well as access to renewable resources.
The California ISO Board approval is a significant step in the overall approval process for new transmission lines, but the Sunrise portion of this project also needs approval from the California Public Utilities Commission. The Greenpath portion needs approval from its local regulatory authority. These reviews will include analysis of environmental line-routing issues. “We hope the CPUC will give appropriate weight to the Cal-ISO’s decision that this project is needed,” said Reed. “The Commission has asked us to include the Cal-ISO’s need determination as part of our amended project application. We expect the regulatory review process will begin soon, and look forward to a Commission decision by the middle of next year to keep us on track to get this project in service as soon as possible.”