Completion of California Trans Bay Cable Draws Near

---

Researched by Industrial Info Resources (Sugar Land, Texas)--Completion of the 53-mile, 400-megawatt (MW) high-voltage direct-current (HVDC) Trans Bay Cable Project is drawing near after more than two years of construction. Completion is scheduled for March 20. Line testing has commenced, and 200 MW of power has been transmitted through the underwater cable, which runs in a trench in San Francisco Bay from converter stations in San Francisco and Pittsburgh, California. The new HVDC cable will supply more than 40% of San Francisco's power from plants in California and the western United States.

The HVDC cable will allow the California Independent System Operator (CAISO) to provide reliable transmission capacity to San Francisco in 2010 and beyond. The cable will reduce the need for in-city generation, increasing overall security and system reliability and providing potential savings to customers.

Construction of the Trans Bay Cable Project began with construction of the Pittsburgh converter station in November 2007, followed by the San Francisco converter station in January 2008. Installation of the HVDC cable began in October 2009.

HVDC cables are used to reduce the energy lost in the transmission process by overcoming the resistance of the wires. For a given quantity of power transmitted, the higher voltage reduces the amount of transmission power loss. The advantage of HVDC is the ability to transmit large amounts of power over long distances with lower capital costs and lower power losses than alternating current. The disadvantages of HVDC are in conversion, switching, control, availability and maintenance.

The project is a partnership between the City of Pittsburgh, Pittsburgh Power Company and Trans Bay Cable LLC, which was acquired by SteelRiver Infrastructure Fund North America (San Francisco) in June 2008.

The consortium building the project consists of turnkey contractor Siemens Power Transmission & Distribution (Columbia, Maryland) and WorleyParsons (Houston, Texas), which provided engineering services and permit management, as well as Prysmian Energy Cables and Systems (Milan, Italy), which supplied the submarine cables. Labor was provided by the International Brotherhood of Electrical Workers (IBEW) Local 6 and 1245.

View Project Report - 6004455

Industrial Info Resources (IIR) is the leading provider of global market intelligence specializing in the industrial process, heavy manufacturing and energy-related markets. For more than 26 years, Industrial Info has provided plant and project opportunity databases, market forecasts, high resolution maps, and daily industry news.