Hydropower Generation near Thakhek Loop in Laos - by Hobo Maps- Go to Hydropower Projects Web Page - - - Home
The 5 hydropower dam projects around the Thakhek Loop are displayed below:
Five dams in and around Thakhek Loop area summarized below. Total output of this group is 2,200 MW (Megawatts) - about one fourth of all hydropower output in Laos in 2021.
(1) The first dam near the Thakhek Loop was the Theun-Hinboun Dam finished in 1998. This dam is a Run-Of-River type without a large reservoir that diverts water from one watershed into another by a long underground channel. Total cost was about US $260 million and the operation has been a commercial success with significant profits. 220 MW generating capacity
(2) The Nam Gnouang 8 Dam was added in 2012 as a supplement and expansion of the Theun-Hinboun Dam system. Basically is a storage reservoir holding pond of 105 sq. km to regulate water flows into the Nam Theun river and the Theun-Hinboun Dam. Total cost was estimated US $665 million. 60 MW + 220 MW = 280 MW capacity
(3) Nam Theun 2 Dam was finished in 2014. This dam diverts water from one watershed into another by a long underground channel and has a conventional dam design with a large reservoir of 450 sq. km. Estimated total cost is US $1.4 billion. 1,080 MW capacity
(4) Nam Hinboun Dam 1 is under construction in 2021 and expected to be completed and begin generating electricity soon. 15 MW capacity
(5) Nam Hinboun Dam 2 (Thong Long Dam) is partially constructed in 2020 but all activity has been halted with uncertain future. 30 MW design capacity
Thakhek Loop area has great terrain for hydroelectric dams. The Nakai Plateau is about 400 meters higher than the lower area with a steep dropoff to the south along the narrow Nakai Escarpment. This dropoff is used to increase water pressure coming into turbines below which makes generating electricity more efficient.
Image below shows Nam Theun 2 Project
DESCRIPTION OF THE NAM THEUN 2 (NT2) PROJECT - The Project dams the Nam Theun (River) in Khammouane province with a 48 m high dam and 13 saddle dams to create the Nakai reservoir impounding some 195 km of the river and its tributaries on the Nakai Plateau. Water from the reservoir falls about 400 meters through a tunnel to a power station located at the base of the Nakai escarpment, taking advantage of the difference in elevations between the Nakai plateau and the Gnommalat plain. From the power station water flows into a regulating pond and then via a 27 km downstream channel into the Xe Bang Fai (river). The power station has a generating capacity of 1,080 MW, 995 MW of which will be exported to Thailand via a 138 km-long 500-kilovolt double-circuit transmission line. EDL will receive 75 MW for use in the Lao PDR via a 70 km-long 115 kV transmission line to Thakhek. The total estimated cost of the Project is $1.3 billion USD.
Huge NT2 Headrace Tunnel below:
Good info at NT2 Visitor Center - at bottom of hill south of Nakai town on Road 1E - at Power Station with turbines
see nice video of Nam Theun 2 Reservoir and Nakai area HERE .
Download excellent PDF document that explains entire NT2 project from start to finish with pictures and diagrams -
https://www.barrages-cfbr.eu/IMG/pdf/06_ji_cfbr_2012_mourrat_nt2.pdf
Theun-Hinboun Hydropower Project
The Theun-Hinboun Hydropower Project is a 210 MW (megawat) trans-basin water diversion project located north of National Road 8 not too far from Na Hin town. It was completed in 1998 at a cost of $260 milion dollars. The project includes a 5.5 km long headrace tunnel (5.64 meter diameter) and a 900m-long penstock excavated by drill and blast method with a surge chamber for the installed power capacity of 2 x 105 MW = 210 MW.
Nam Gnouang Dam - a 280 MW Theun-Hinboun Expansion project to expand the 210-MW Theun-Hinboun hydroelectric project was completed in 2012 at a cost of $665 million dollars. The expansion project includes a 220-MW addition to the Theun-Hinboun power station plus a 60-MW power plant, a six-kilometer headrace tunnel dug by tunnel-boring machine and a new 70-meter-tall concrete dam on the Nam Gnouang River.
The new dam is 20 kilometers upstream from the existing Theun-Hinboun Dam. It creates a reservoir to regulate river flows into the Theun-Hinboun Reservoir headpond increasing power output in the dry season. (210 + 280 + 60 = 550 MW total for both original and expansion projects)
Theun-Hinboun Expansion Project Diagram below:
Images below of the Tunnel-boring machine (TBM) used for the Expansion project in 2012 (not used for the original Theun-Hinboun Dam project in 1998.
Thakhek Loop Area Drainage Map below
Click HERE to see our Thakhek Loop Map
Click HERE to see our Thakhek Loop Terrain Map
Click HERE to see our Thakhek Loop Geographic Map