Tongariro Power Scheme

The Tongariro Power Scheme is located on the central volcanic plateau south of Lake Taupo. The scheme and its structures extend from the southern flanks of Mount Ruapehu in the south, to the southern point of Lake Taupo in the north, and along either side of the mountain range formed by Ruapehu, Ngauruhoe and Tongariro. The scheme taps a catchment area of more than 2600 sq km.

The scheme is operated to provide water to the Tokaanu (240MW) and Rangipo (120MW) power stations and uses a series of lakes, canals and tunnels to do so. Tokaanu Power Station is located on the slopes of Mount Tihia, near the township of Turangi, south of Taupo. Rangipo Power Station is situated underground in the Kaimanawa Forest Park, on the eastern side of the Tongariro Power Scheme.

A description of the Tongariro Power Scheme.

 

KEY FACTS

TONGARIRO POWER STATION
Year Commissioned	Tokaanu - 1973 Rangipo - 1983 Mangaio - 2008
Total Capacity	Tokaanu - 240MW Rangipo - 120MW Mangaio - 2MW
Generation Units:	Tokaanu - Four 60MW units Rangipo - Two 60MW units Mangaio - One 2MW unit

 

Contribution to the National Grid

The Tongariro Power Scheme typically contributes 1350 GWh (Gigawatt hours) per annum. - about 4% of the country's total electricity generation. The Tokaanu power station is also used as a frequency control station (controls the power system frequency) when required.

 

Challenges faced in operating the scheme

The Tongariro Power Scheme sits on the fringe of the Tongariro National Park, an area that is classified on the World Heritage List for its ecological and cultural values. Furthermore, the scheme is built on the headwaters of two significant river systems (the Tongariro and Whanganui rivers) and Genesis Energy has many resource consent conditions to ensure the preservation of these rivers. Monitoring and reporting to ensure compliance with the consent conditions forms a significant part of the operation of the scheme. Genesis Energy also has mitigation agreements in place to manage its effects on the environment. In addition, environmental initiatives have been set up over and above the consent related legal obligations.

The volcanic and lahar risks from Mount Ruapehu is also monitored from the Tongariro operations centre and when these events occur the scheme is managed to prevent any lahar material (which would have not normally entered the Tongariro and Whanganui catchments) from entering the rivers. Other challenges include, minimising excess spill of water (other than required for minimum flows), ensuring we meet our generation targets in the electricity market, and looking for opportunities to better use our resources.

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Rivers, Lakes and Rainfall

Environmental Reporting