Tasersiaq

Tasersiaq is Greenland's longest lake and lies around 60 miles south of Kangerlussuaq. The surface of the lake is at an altitude of approx. 2240 feet. Owing to the high fells surrounding the lake, it has a relatively small precipitation catchment area (from where precipitation flows to the lake). The lake's most important source of water is melted ice from glaciers at the southern and eastern ends of the lake. This means that the water is full of silt particles from the glaciers and the lake is therefore devoid of fish.
 

In order to exploit the potential power in the best possible manner, the water from Tasersiaq has to be led southwest through an approx. 18-mile long tunnel to a power station in the inner part of the Fjord of Eternity.

Tasersiaq (Photo: Greenland Development)
 

In the earliest engineering studies from the 1970s it was supposed that the tunnel should follow the natural course of the river northwest to Paradise Valley, which has its mouth at Kangerlussuaq.

There were, however, both considerations of the surrounding countryside as well as technical reasons for choosing a tunnel running to the Fjord of Eternity, since this would avoid a permanent facility in the protected Paradise Valley, as well as resulting in both a shorter tunnel and a greater difference in height between the lake and the power plant.

Other construction work for this project includes two dams, whereby the tallest will probably have a height of 121 feet.

The most important reason for Tasersiaq being raised from its current level is the size of the reservoir: With a bigger and deeper lake, a continuous supply of water to the tunnel is assured during the winter, and the capacity of the lake will thus compensate for a lower inflow of rain and meltwater in cold, dry years. Surveys of the lake have indicated that in certain areas it is quite shallow.

The drop from the lake to the surface to the fjord will be 2325 feet when the reservoir is full. The surface area will be approx. 73 square miles with a maximum variation in the head of water of 80 feet.

The illustration shows the size of Tasersiaq at maximum water level with the dams installed. The edge of the natural lake is indicated by a red line. (source: Alcoa / PB Power)

Based on the last 20 years' hydrological data, Tasersiaq has proved to contain a greater energy potential than originally estimated. This compensates for the major engineering challenge of establishing a hydroelectric power plant, tunnel and dams in such a remote area. Tasersiaq is without doubt Greenland's most attractive hydropower potential.

 Expected energy capacity for Tasersiaq: 475 - 500 MW continuous output.

 Archeology:

Tasersiaq was historically an important region for summer hunting of reindeer by the Inuit, and countless finds of relics of the life of the reindeer hunters can be found along the lake. Read more about the archeological surveys at Tasersiaq and Tarsartuup Tasersua here or at the National Museum's website.