The advantage of High Voltage DC (HVDC) is that the power losses
over a transmission line (the square of the current multiplied by the
resistance of the wire) then become very low.
China is the world's largest deployer of HVDC and UHVDC (ultra-high voltage
DC) technology.
In an article today by Peter Fairley at the IEEE Spectrum Magazine web
site, China's State Grid has broken a new world record with a UHVDC
deployment that operates at 1.1 million volts over 3000km.
Quote:
|
Originally Posted by Peter Fairley, IEEE
Jin Zhang, a senior engineer and deputy division head in State Grid’s DC transmission project department, told IEEE Spectrum during interviews in Beijing last year that State Grid began developing 1100-kv UHVDC technology more than a decade ago. They recognized, he said, that China would need to transfer power farther over distances that would incur large losses on 800-kv lines.
|
Quote:
|
Originally Posted by Peter Fairley, IEEE
UHVDC technology is seen by Chinese president Xi Jinping as a key technology for his “Belt and Road” international development program. And at the UN’s 2015 Sustainable Development Summit Xi proposed the construction of intercontinental power links to massively scale-up cross-border sharing of renewable energy.
But UHVDC also has an important role to play domestically, where Xi has promised to turn China’s skies blue again. Specifically, Xi has committed to ending rampant wastage of renewable power generation, whereby wind, solar and hydro power plants are deliberately shut off due to grid capacity and stability limits or to simply make room for coal-fired generation.
State Grid’s new 1100-kv line could help reduce renewable energy curtailment because Xinjiang’s wind and solar power plants are among China’s largest and also the country’s most heavily curtailed. More than one-fifth of Xinjiang’s solar generating potential and one-quarter of its wind power was squandered in 2017, according to Chinese government statistics. Sending that power to eastern China instead of wasting it would help State Grid meet Xi’s promise to shrink curtailment to less than 5 percent in all regions by 2020.
State Grid is working hard to meet that goal, according to Zhang. While 13-gigawatts of new coal power generation was planned along with State Grid’s 1100-kv UHVDC project, Zhang told Spectrum that many of the anticipated plants were cancelled. “At least more than half will be renewable power,” he said of the power exports the new line will carry.
|
Combined with massive solar and wind power deployment in Australia,
a UHVDC interconnect with South East Australia has the potential,
in the future, to become one of Australia's largest export markets.
The investment would be considerable but the region has an unquenchable
demand for electrical power.
Article here :-
https://spectrum.ieee.org/energywise...ission-records
