Mighty River Power - History

History

Mighty River Power was established on 1 April 1999, when the 1998 reform of the electricity sector took effect. The Electricity Corporation of New Zealand (ECNZ) was broken up into three state-owned generating companies - Mighty River Power, Genesis Energy and Meridian Energy. Mighty River Power took over the ownership and operation of the eight hydroelectric power stations on the Waikato River, New Zealand's longest, and also inherited the assets of two largely decommissioned oil-fired power stations at Marsden Point, near Whangarei.

In addition, the 1998 reforms forced the separation between lines (transmission and distribution) and supply (generation and retailing). On 1 April 1999, Mercury Energy, then the major lines and supply company for Auckland, New Zealand's largest city, was split between lines and supply. Mighty River Power inherited Mercury Energy's retail base and its share in the Southdown Power Station (in conjunction with the Natural Gas Corporation). Mercury Energy then became the name of Mighty River's retail business, and the sub-transmission and distribution business of Mercury Energy was renamed Vector.

In 2000, Mighty River purchased into the Rotokawa geothermal power station, to operate and maintain the station, and own the geothermal turbines in a joint venture with the Tauhara North No.2 Trust. Also that year, Mighty River Power commissioned the Mokai geothermal power station in a joint venture with the Tuaropaki Trust. One aspect that sets Mighty River Power apart from other geothermal generators is that it works in partnership with Māori landowners (the tāngata whenua) to benefit both Mighty River power and the tāngata whenua.

In September 2002, Mighty River gained 100 percent ownership of the Southdown power station.

In 2004, Mighty River announce plans to refurbish the Marsden B plant to fire it on coal to increase supply security north of Auckland. Marsden B had been mothballed since it was completed in 1978 due to rising oil prices following the 1973 oil crisis and there being cheaper alternatives available. Greenpeace staged a nine-day occupation of the site in 2005, and after the Northland Regional Council granted consent, appealed to both the Environment Court and High Court, eventually overturning the consent. Mighty River appealed the High Court decision to the Court of Appeal, but in March 2007 dropped the proposal.

In 2008, Mighty River increased its generating capacity by opening the 100 MW Kawerau geothermal power station, increasing supply security to the eastern Bay of Plenty, a large timber processing area. In 2010, it opened the 140 MW Nga Awa Purua geothermal station near Taupo, complete with the largest single-shaft geothermal turbine in the world. The commissioning of Nga Awa Purua increased Mighty River's geothermal capacity to 385 MW, becoming the nation's largest geothermal electricity generator with 52.7 percent of all installed geothermal capacity.