Manapouri Power Station

Manapōuri Power Station
The Manapōuri Power Station machine hall
Location of Manapōuri Power Station in New Zealand
Country	New Zealand
Location	west end of Lake Manapōuri, Fiordland National Park, Southland
Coordinates	45°31′17″S 167°16′40″E / 45.52139°S 167.27778°E / -45.52139; 167.27778
Status	Operational
Construction began	February 1964[1]
Opening date	September 1971[1]
Construction cost	NZ$135.5 million (original station) NZ$200 million (second tailrace tunnel) NZ$100 million (half-life refurbishment) [1]
Owner(s)	Meridian Energy
Reservoir
Creates	Lake Manapōurib
Catchment area	3,302 km2 (1,275 sq mi)[1]
Surface area	141.6 km2 (54.7 sq mi)[1]
Maximum water depth	444 m (1,457 ft)
Manapōuri Power Station
Type	Conventional
Turbines	7× vertical Francis[1]
Installed capacity	854 MW[1]
Capacity factor	68.4% / 79.7%c
Annual generation	5100 GWh[2]
b Lake Manapōuri is a natural lake - the drop between it and the sea is used by Manapōuri station. ^c The former figure is based on the installed capacity of 854 MW, while the latter figure is based on the resource consent limited capacity of 800 MW

Manapōuri Power Station is an underground hydroelectric power station on the western arm of Lake Manapouri in Fiordland National Park, in the South Island of New Zealand. At 854 MW installed capacity (although limited to 800 MW due to resource consent limits^[3]), it is the largest hydroelectric power station in New Zealand, and the second largest power station in New Zealand. The station is noted for the controversy and environmental protests by the Save Manapouri Campaign against raising the level of Lake Manapouri to increase the station's hydraulic head, which galvanised New Zealanders and was one of the foundations of the New Zealand environmental movement.

Completed in 1971, Manapōuri was built primarily to supply electricity for the Tiwai Point aluminium smelter near Bluff, some 160 km (99 mi) to the southeast. The station utilises the 230-metre (750 ft) drop between the western arm of Lake Manapouri and the Deep Cove branch of the Doubtful Sound 10 km (6.2 mi) away to generate electricity. The construction of the station required the excavation of almost 1.4 million tonnes of hard rock to build the machine hall and a 10 km tailrace tunnel, with a second parallel tailrace tunnel completed in 2002 to increase the station's capacity.

Since April 1999, the power station has been owned and operated by state-owned electricity generator Meridian Energy.