China’s under-utilised ultra-high-voltage power lines no silver bullet to rid grid of bottlenecks
State Grid plans to plough some 600 billion yuan into UHV lines by 2020
Utilisation of China’s ultra-high-voltage (UHV) power transmission lines, designed to send excess electricity in remote interior regions to coastal centres battling worsening air pollution, has been lower than expected, according to analysts.
The high-capacity UHV lines, more efficient and economic for long-distance transmission, are expected to cost state-owned State Grid Corporation more than 600 billion yuan (HK$711 billion) to build until 2020. But they’ve also turned out to be no panacea for the nation’s renewable power distribution bottlenecks.
“Utilisation of the UHV lines remains below expectations [due to] many factors … such as the performance of connected generation plants, constraints in the local power grids, [hydro power resource] conditions, as well as [power] demand conditions,” Hu Xinmin, senior manager at Hong Kong-based industry consultancy The Lantau Group, said in a report.
“As such, efficiently coordinated planning of grid and generation [capacity], under changing economic and regulatory conditions, will become even more important to ensure better utilisation of fuel, environmental and capital resources.”
Citing figures from State Grid, which has a power distribution monopoly in all but five southern regions in mainland China, he noted its first three UHV lines, commissioned between 2009 and 2012, had reached capacity utilisation of only 21 per cent to 56 per cent in 2014.
China is the first nation with the stated ambition of using UHV power lines as the “core” to inter-connect its regional power grid networks into a “strong and smart” national network, a strategy championed by State Grid around a decade ago.
To meet this original 2020 target, China would need to more than double its UHV development effort, which seems unlikely given the challenges
