Laos Hydropower Exports to Vietnam Info by Hobo Maps - Go to Hydropower Projects Page - - - HOME

In April 2024 Electricity of Vietnam (EVN) reported that it has signed 19 power purchase agreements (PPAs) with investors to purchase electricity from 26 hydropower plants in Laos with a combined capacity of about 2,240 MW.

As of February 2025 there seem to be 11 hydropower projects based in Lao PDR with a combined output of about 1,180 MW that were exporting electric power output cross-border to Vietnam as seen in the chart below.

Most of this power export from the Lao plants is transmitted to the Vietnam border by 220 kV transmission lines financed and constructed by Independent Power Producers (IPPs) and not by EDL or the Lao government. On the Vietnam side the transmission lines and stations have mostly been constructed and financed by Electricity of Vietnam (EVN).

The privately-financed high voltage transmission lines inside Laos typically operate under concession agreements between the Independent Power Producer and the Lao government.

Electric power transfers along all these cross-border transmission lines will probably be managed on a day-to-day basis by Electricity of Vietnam Power Management Board (EVNPMB).

The pricing tariff for these hydroelectric power exports seems to be based on Memorandums of Understanding (MOUs) between the governments of Laos and Vietnam which are revised every five years. For the 5 calendar years 2025 thru 2029 the tariff for hydropower exports to Vietnam has been set at a maximum price of .0678 US Dollars per unit (such as KWh). The previous 5-year period maximum rate was higher at .0695 US Dollars per unit. One other report indicates that the average retail tariff rate prior to year 2025 in Vietnam was about .0847 US Dollars per unit (excluding VAT).

The first exports of hydropower electricity from Laos to Vietnam began in 2016.

Line 1 from Xekaman 1 and Xekaman-Sanxay HPPs to Pleiku Gia Mai Vietnam (220 kV transmission line):

The 220kV double-circuit transmission line from Xekaman 1 Hydropower Plant in Laos to Pleiku 2 Transformer Station in Vietnam. The line is 190 km long, of which 71 km is from Xekaman 1 Hydropower Plant to the Laos-Vietnam border (Bo Y Border Gate) and 119 km on to Pleiku Gia Mai Vietnam;

Xekaman 1 and Xekaman-Sanxay power plants are located within 2 km of each other and operate together. Xekaman 1 was completed in 2016 and Xekaman-Xanxay in 2018. Power from both is exported along a 220 kV transmission line with a 70 km section from Xekaman 1 Hydropower Plant in Lao PDR to the Vietnam border (invested by Viet-Lao Power Joint Stock Company) and a 119 km section from Bo Y border gate in Kon Tum Province, Vietnam to Pleiku 2 substation in Vietnam (invested by EVN)

The guaranteed transmission capacity of the line is 500 MW, the maximum transmission capacity is about 800 MW.

Xekaman 1 hydropower and Xekaman-Sanxay hydropower have combined power output capacity of 322 MW and annual output potential of 1,220 GWh. 20% of the output is planned to be used for Lao domestic consumption and 80% exported to Vietnam through a 230 kV transmission line connecting Ban Sok in Lao PDR to Pleiku Gia Lai in Vietnam.

The Xekaman 1 hydropower project spent over US$ 54 million on construction of the 70 km-long power transmission lines (about $770,000 US per km).

The Power Purchase Agreement with Electricite Du Laos (EDL) was signed on October 28, 2010 and the purchase agreement with Electricity of Vietnam (EVN) was signed on March 02, 2011.

In 2018, Viet-Lao Joint Stock Company and Convalt Energy proposed floating solar power as a potential addition to the HPP at Xekaman 1 reservoir. A press release indicated that 250 MW of ground-mounted solar power and 280 MW of floating solar could be developed and exported to Vietnam through existing transmission lines.

Line 2 from Xekaman 3 to Dak Ooc & Thanh My Vietnam (220 kV transmission line):

A cross-border transmission line connects XeKaman 3 Hydropower Plant to Dak Ooc & Thanh My substations in Vietnam through a 220 kV dual circuit line with a length of 92 km, 40 km inside Laos and 52 km in Vietnam. The line has guaranteed transmission capacity of 300 MW and maximum transmission capacity of about 550 MW.

Although the transmission line to Vietnam was completed in 2013 it wasn't until 2022 that actual power was transmitted and exported to Vietnam from Xekaman 3. The delay was caused by a penstock failure and subsequent repairs unrelated to the transmission line.

The transmission line on the Laos side was constructed and invested by the owners and developers of the Xekaman 3 hydropower project while the transmission line and stations on the Vietnam side were constructed and invested by Electricity of Vietnam (EVN).

The 250 MW Xekaman 3 hydropower project has average annual energy production capability up to 978 GWh with 90% of the electricity generated planned for export to Vietnam.

Xekaman 3 Power Ltd. Co. is owner of the Xekaman 3 project with Viet-Lao Power Joint Stock Company as the majority shareholder with 85% share while Electricite du Laos (EDL) holds 15%.

The transmission line project inside Laos is operating under a 25-year Build-Operate-Transfer concession agreement that may have started in 2022.

Day-to-day transmissions along the line will be managed by Electricity of Vietnam Power Management Board 2 (EVNPMB 2).

Line 3 from Nam San 3A & 3B and Nam Tai (Tay) to Tuong Duong (Nghe An) Vietnam (220 kV transmission line):

On 16 May 2022 a new power receiving substation was constructed and energized about 6 km inside Vietnam at Tuong Duong (Nghe An). Power from Nam San 3A & 3B as well as from Nam Tai (Tay) is now being exported to Vietnam along a 90 km long 220 kV double-circuit transmission line, 16 km of which is in Laos and 74 km inside Vietnam.

The transmission line project on the Vietnam side was constructed and invested by Electricity of Vietnam National Power Transmission Corporation (EVNNPT). Not sure who constructed and financed the 220 kV transmission line on the Lao side but it could have been by Nam Tai Power Sole Co., Ltd.

The project is expected to eventually transmit the output from 16 hydropower plants in the Nam Mo river basin in Laos to Vietnam with a combined capacity of about 850 MW. The transmission line has a maximum capacity of 1,000 MW.

On December 31, 2021, BCPG Indochina entered a share purchase agreement with Nam Tai Power Sole Co., Ltd. to acquire a 25 per cent share in the Nam Tai transmission line project. BCPG is the owner of Nam San 3A & 3B hydropower projects and has acquired the right to transmit output from these plants along the line.

The transmission line in the future is expected to transmit and export power output from the projects - Nam Sak, Nam Xao (Sao) cluster, Nam Mo 1 & 2, Nam Chao & maybe Nam Mouan.

Line 4 from Nam Kong 1, 2 & 3 to Bo Y Substation Ngoc Hoi district, Kon Tum province, Vietnam (220 kV transmission line):

The transmission line project connecting Nam Kong 1, 2, 3 Hydropower Plant Cluster (Laos) to the Vietnamese power system at Bo Y in Ngoc Hoi district, Kon Tum province, Vietnam was completed and energized in May 2023.

When completed, Houay KaOuane HPP is also planning to export and send its power output to the Bo Y substation in Vietnam. Maybe this will be along a separate 220 kV transmission line about 32 km-long with 26 km inside Laos and 6 km inside Vietnam. But it may connect to the Nam Kong cluster transmission line instead since that line runs quite close to Houay KaOuane HPP

The transmission line project on the Vietnam side is constructed and invested by Electricity of Vietnam (EVN). Not sure who constructed and financed the 220 kV transmission line on the Lao side but it could have been CS Energy.

Nam Kong 1 hydropower project was finished in June 2021.

Nam Kong 2 hydropower project was completed in 2018 and began selling power to Electricite du Lao (EDL) for domestic consumption at that time.

In early 2020, CS Energy entered into a Power Purchase Agreement with Electricity of Vietnam (EVN) for sale and export of output from Nam Kong 2&3 power plants to Vietnam. This requires the existing EDL purchase contract to be terminated and replaced with the new export contract. Not sure exactly when the sale of output to EDL was terminated.

Nam Kong 3 HPP was finished in November 2023.

In 2025 it seems that:

Nam Kong 1 sends its power output about 21 km via a 220 kV line to Nam Kong 2&3 combined substation.

Nam Kong 2 sends its output about 7 km to Nam Kong 2&3 combined substation along a 110 kV line.

Nam Kong 3 sends its output about 9 km to Nam Kong 2&3 combined substation.

Power from all 3 Nam Kong projects is sent from Nam Kong 2&3 combined substation about 86 km along 220 kV line to Bo Y substation about 6 km inside Vietnam near the Bo Y border gate.

The chart below shows power transmissions from Nam Kong 1,2&3 plants before the Nam Kong 2&3 combined substation was planned and needs to be adjusted to include that combined substation.

Line 5 from Nam Emoun HPP in Laos to Dak Ooc Substation in Vietnam (220 kV transmission line):

The transmission line system includes:
A 220 kV double-circuit transmission line from the Nam Emoun Hydropower Plant to the Dak Ooc Vietnam switching substation with the section on Lao territory about 52 km long and the section on Vietnamese territory about 13.4 km long; and
A 4-circuit 220 kV transmission line about about 1.9 km long from Dak Ooc substation into the existing 220 kV Xekaman 3-Thanh My double-circuit transmission line.

On May 28, 2024, the 220 kV Dak Ooc switching substation was energized to facilitate the grid connection from Nam Emoun Hydropower Plant in Laos to the Vietnamese power system grid. The Dak Ooc substation is located in Nam Giang district, Quang Nam Province of Vietnam.

The transmission line on the Laos side was constructed and invested by the owners and developers of the Nam Emoun hydropower project while the transmission line and stations on the Vietnam side were constructed and invested by Electricity of Vietnam (EVN).

Electric power transfers along this transmission line are expected to start in early 2025 and will be managed by Electricity of Vietnam Power Management Board 2 (EVNPMB 2) pursuant to a Power Purchase Agreement signed in early 2020.

In 2025 it is expected that power from Houay LaNgae HPP will start to be transmitted to the Nam Emoun transformer station via a 41 km long 230 kV line and add to the power going to Dak Ooc Station in Vietnam.

Nam Emoun project generating capacity is 129 MW with 427 GWh expected annual output capacity.

Chaleun Sekong Energy Co., Ltd. (CS Energy) is the major shareholder in Nam Emoun HPP.

Line 6 from Nam Sam 1, 1A & 3 to Nam Cong Substation Vietnam (220 kV transmission line):

On December 21, 2024, Electricity of Vietnam National Power Transmission Corporation (EVNNPT) and the Northern Power Project Management Board (NPMB) coordinated with relevant units to successfully energize the 220 kV Nam Sam-Nong Cong transmission line project. The part in Laos is 3 km long, the part in Vietnam is about 130 km long.

EVN has signed 5 PPAs to buy electricity from 10 hydropower plants in Laos with a total capacity of 459 MW . All are located in Houaphan Province, Lao PDR.

For Nam Sam 3 (156 MW) and Nam Sam 1A (50 MW) projects, EVN has held many meetings with the investor regarding the transmission line project.

Other projects that may export on this transmission line include Nam Sam 3A (45 MW), Nam Yeuang Hydropower (84 MW) and Nam Neun 1 Hydropower (124 MW).

The transmission line in Vietnam was constructed and financed by Electricity of Vietnam National Power Transmission Corporation (EVNNPT). On the Laos side, construction was probably done by the developer of Nam Sam 3 HPP.