The Xe Pian & Xe Namnoy hydropower scheme is being implemented by the client as a BOT venture with the government of People's Democratic Republic of Laos for power exports to Thailand.
The headworks of the high-head project are located on the Boloven plateau some 500 kilometres south-east of the capital city of Vientiane. The tailworks discharge into the Xekong River, a major Mekong tributary, at the foot of a steep, 800 metre-deep escarpment. The headworks consist of a diversion weir and two fill dams which are 49 metres and 78 metres high with their appurtenances. The impounded reservoirs are interconnected via water transfer tunnels. The 17 kilometre long waterways comprise headrace tunnel, surge tank, vertical shaft, high pressure tunnel and open steel penstock. Three Pelton units of 124 MW are installed in the open-air powerhouse.
Pöyry provided feasibility study services such as photogrammetric and terrestrial topographic mapping, geological investigations, environmental impact assessment, feasibility design, simulation and optimisation of plant size and operation, economic and financial analyses, advisory services during PPA negotiations.