In Russia and Kazhakstan, there are already powerlines with voltages of more than 1000 kV in operation. The first of this line is the line from Ekibastus to Kokshetau in Kazhakstan. Work on the erection of a 1500 kV DC line from Tambov to Ekibastus started in the 1980ies, but was cancelled after collapse of Soviet Union.
Megavolt lines exist also in China. In Japan some powerline for 1000 kV were built, but are operated with lower voltage. In USA an experimental powerline for 1333 kV DC was built near Celilo, Oregon, the terminal of 400 kV DC Pacific Intertie.
A river powerline crossing of a 1150 kV powerline in Russia (
http://dvoika.net/50let/index34.html )
Pylon of 1150 kV powerline in Kazhakstan. 1150 kV powerlines have 10 metres long insulators
Free-standing pylon of unfinished 1150 kV powerline in Russia
The field strength on the conductors is so high, that corona lighting can occur. See
http://www.energo-info.ru/images/pdf/Kutuzova.pdf ! Perhaps can a Russian forumer translate the text.
Pylons of unfinished 1500 kV DC powerline Tambov-Ekibastus. It would be, if completed with a length of 2400 km the longest powerline in the world and that with a transmission rate of 6000 MW that with highest transmission rate.
Finished section of the line
In China, a 653,8 km long 1000 kV powerline with a transmission rate of 3000 MW was built in 2008, which runs from Jingdongnan to Jinmen and crosses also Yangtze and Yellow River.
Strainer of 1000 kV powerline in China
Construction drawings of Chinese 1000 kV towers
In Japan, there is no operational 1000 kV powerline, but there are some powerlines designed for 1000 kV. In opposite to China, Russia and Kazhakstan, these lines are installed on pylons for 2 circuits.
Pylons for several voltage levels in Japan. According to
http://www015.upp.so-net.ne.jp/overhead-TML/shurui.html pylons designed for 1000 kV in Japan are normally between 90 and 110 metres tall.
Close look at 1000 kV tower in Japan
Linear Mode
