First 800-kV High-Voltage Direct-Current Link in China Now Fully Operational; Transmission of Hydro Power to Pearl River Delta
Siemens Energy and the utility China Southern Power Grid have put into operation the second pole of a world-record high-voltage direct-current (HVDC) system. The transmission capacity has now been doubled to 5,000 megawatts (MW). With one pole operating at plus 800 kilovolts (kV) and the other at minus 800 kV, the voltage difference between the poles reaches the world record of 1,600 kV DC.
In December 2009, the link had also set the world record for first DC operation ever at a voltage level of 800 kV DC. Since that date, Pole 1 has operated at nominal power of 2500 MW without any interruptions.
This has been an ambitious project including ground-breaking product developments and we have ultimately even managed to complete it ahead of schedule. With DC systems operating at ultra high-voltage levels we now have the transmission technology of the future in our portfolio. This technology is ideal for transporting clean, renewable power over thousands of kilometers to consumers—with nearly zero losses.
—Udo Niehage, CEO of the Power Transmission Division of Siemens Energy
The 5,000 MW of CO2-free power is produced by several hydro power plants in the remote Yunnan Province and will be transported with minimal losses to the rapidly growing industrial region in the Pearl River delta in Guangdong Province with its megacities Guangzhou and Shenzhen.
This will reduce annual CO2 emissions by more than 30 megatons compared with equivalent fossil-fueled power plants in the power grid of Guangdong Province.
The Yunnan-Guangdong UHVDC system covers a transmission distance close to 1,500 kilometers (932 miles). The new ultra-high voltage level of 800 kV offers global transmission operators economical low-loss bulk power transmission over even longer distances. Distances of 3,000 kilometers (1,864 miles) and even more are feasible now with UHVDC technology of this kind: At a transmission capacity of 5000 MW losses are as low as around 2% per 1000 kilometers, plus less than 1.5% losses for both converter stations at the sending and receiving end of the transmission line.
Together with its Chinese partners, Siemens designed the entire HVDC system for the Yunnan-Guangdong project and developed and supplied the core components for this technology, which included 800-kV and 600-kV converter transformers, DC filters and all 800-kV direct-current components.
Energy-efficient HVDC systems for highly reliable, low-loss transmission of large amounts of power over long distances are part of Siemens’ Environmental Portfolio. In fiscal 2009, Siemens generated revenue of €23 billion with products and solutions from its Environmental Portfolio. During 2009, Siemens customers worldwide were able to reduce their carbon dioxide (CO2) emissions by a total of 210 million tons with products and solutions from the Siemens Environmental Portfolio.