The high-voltage Pacific AC-DC Intertie

SCE, Pacific Gas & Electric, San Diego Gas & Electric and the Los Angeles Department of Water and Power built the Pacific AC-DC Intertie between 1967 and 1970. The Intertie system consists of two 500-kilovolt AC lines and one 500-kilovolt DC line. The DC line was the first major high-voltage DC line constructed in the U.S. With subsequent expansions, this system of AC and DC lines is capable of transporting almost 8,000 megawatts of power.