The energy in flowing water can be transformed into electricity by directing the flow of water to pass through turbines. The turbines are connected to electrical generators, such that the movement of water causes the turbines to rotate, which results in the production of electricity.
There are two types of systems that can be used in hydroelectric power plants: a “run-of-river” system or a “storage” (dam) system. A run-of-river system contains turbines that are situated in rivers that are sufficiently steep. Storage systems involve the construction of dams to create reservoirs of water allowing for control of water flow. Small run-of-river hydropower systems generally have lower environmental effects than storage systems but they also have more maintenance requirements. A run-of-river system in the Arctic has to be installed in a river that does not freeze to the bottom during winter to allow for year-round operation or they would have to be removed in winter creating significant additional operating costs. Storage type hydroelectric power plants can produce electricity year-round in Arctic conditions if water reservoirs are maintained at operational levels.
Storage and run-of-river systems have operated successfully in northern jurisdictions such as the NWT, Yukon and Alaska. Potential hydroelectric sites have been identified in Nunavut. In particular, assessments of hydroelectric potential have been completed for various locations near Iqaluit and in the Kivalliq region. In the Kivalliq, many potential sites are far away from community centres resulting in an increase in development costs. The demand for electricity in many Nunavut communities is too low to economically justify hydroelectric development, which has left hydroelectric resources underdeveloped in Nunavut. However if significant mining development occurs there may be opportunities to economically develop these resources in the future. The hydroelectric potential of rivers that flow through the Kitikmeot region have been performed, however, the details are unavailable. Further study of potential hydroelectric development in the Kitikmeot is needed. The first hydroelectric project to be developed in Nunavut would likely be in Iqaluit. The Armshow River Long and the Jaynes Inlet sites have been identified as potential hydroelectric developments.