POWER August 2021 - 6

China Starts Up Turbines at
16-GW Hydro Project After
Four-Year Construction Period
China in late June began operating two
of the world's first 1-GW hydropower
turbines at the Baihetan Hydropower
Station in southwest China. When the
project's 16 generating units are completed
by July 2022 as slated, the 16-GW
Baihetan will become the second-largest
hydropower facility in the world after the
giant 22.5-GW Three Gorges Dam.
Baihetan, which sits on the border of
Ningnan County in Sichuan province and
Qiaojia County in Yunnan province, is part
of a cascade of mammoth hydropower
projects China is building to generate
power (and provide flood control) from the
hydro-rich southwest and deliver it to power-intensive
regions on the eastern coast.
Located downstream on the Jinsha
River (which is the upstream section of
the Yangtze River), it is 182 kilometers
(km) away from the upstream Wudongde
hydropower station-a 10.2-GW project
that began full operation on June 16
(Figure 1)-and 195 km away from the
downstream 13.8-GW Xiluodu hydropower
station, which began full operations
in September 2013.
But startup of the Baihetan's two
turbines is especially notable because
owner and operator China Three Gorges
Corp. (CTGC) marked the milestone only
four years after construction began. And
as President Xi Jinping in a congratulatory
letter to the Baihetan station noted, it
was ridden with complexity. " As a major
project in China's west-east power transmission
program, Baihetan is the largest
and most technically difficult hydropower
project currently under construction in
the world, " he wrote.
The $34 billion project has a 289-meter
(m)-high concrete double-curvature arch
dam, and it adopts an all-underground
powerhouse layout. Sixteen 1-GW Francis
turbines (Figure 2)-each 438 m long,
with a top arch span of more than 34 m,
a height of 88.7 m, and weighing 8,000
tons-will be split along the left and right
banks. The turbine design, owned by
the Chinese government and wholly domestically
manufactured, reportedly has
a maximum efficiency of 96.7%, and a
rated efficiency exceeding 99%.
The plant's generator's runner also reportedly
achieved " zero-counterweight "
runner balancing, which essentially
means that in its manufacturing state,
the runner could meet the residual required
torque imbalance without the
need for a lead-filled counterweight during
a static balance test. Chinese media
widely quoted Qin Daqing, deputy chief
engineer of Harbin Electric Group Motor
Co., who explained: " The smaller the
distribution weight, the higher the manufacturing
technology level and the higher
the manufacturing quality of the runner,
and the better the running performance
after installation in the unit in the future. "
Finally, the project also has a total of
eight throttled tailrace surge chambers
on the right and left banks with a diameter
of 42 m to 48 m-one of the largest
in the world. The total length of the
Baihetan tunnel spans 217 km. In total,
CTGC said, the project required the excavation
of 25 million cubic meters-
" enough to build 10 Egyptian Pyramids
of Khufu, " as Chen Jianlin, chief engineer
of the Baihetan Hydropower Project, and
a member of the East China Institute of
Technology, told reporters.
Baihetan will be connected to the
eastern province of Jiangsu via an
ultra-high-voltage (UHV) line in 2022,
and another UHV line to another eastern
province, Zhejiang province, is also
awaiting government approval. That pow
er is much-needed for reliability in some
industrial regions. Guangdong province
in the south, a major manufacturing hub,
this May imposed short-lived power restrictions
on industry, owing in part to a
rare drought in neighboring Yunnan province
in the southwest, which provides a
crucial hydro-dependent power supply to
the region.
According to China's National Bureau
1. China Three Gorges Corp.'s 10.2-GW Wudongde hydropower plant began full operation of its
12 GE Renewable Energy 850-MW units in June, less than six years after construction kicked
off. Located on the mountainous borders between Yunnan and Sichuan provinces, the facility
marks several records, including for the world's thinnest 300-meter high arch dam. Wudongde
is now China's fourth-largest and the world's seventh-largest hydropower project. Courtesy: GE
Renewable Energy.
6
www.powermag.com
of Statistics, China boosted its power
generation nearly 15% over the first five
months of this year, though it noted the
growth rate fell compared to the same
period year. Earlier this year, the nation's
National Energy Administration (NEA) set
a target to expand its installed renewable
power capacity to 934 GW-42.4%
POWER | August 2021
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POWER August 2021

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