Energy. The electricity distribution business Mercury Energy Limited changed its name to Vector Limited and continued the distribution and transmission operation. Mighty River Power took over the ownership and operation of the nine hydroelectric power stations on the Waikato River, New Zealand's longest river, and inherited assets of two largely decommissioned oil-fired power stations at Marsden Point, near Whangārei and its share in the Southdown Power Station (in conjunction with the Natural Gas Corporation). In 2000, Mighty River Power acquired 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 Mōkai geothermal power station geothermal power station in a joint venture with the Tuaropaki Trust. In September 2002, Mighty River Power gained 100 percent ownership of the Southdown power station. In 2004, Mighty River Power announced 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 Power appealed the High Court decision to the Court of Appeal, but in March 2007 dropped the proposal. In 2008, Mighty River Power 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 Taupō 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 making it the nation's largest geothermal electricity generator with 52.7 percent of all installed geothermal capacity. In 2009, Mighty River Power sold the Marsden B plant for $20 million to an Indian company, United Telecom. Resource consents for dismantling the plant were granted in June 2011, and the 20,000 tonnes of plant and equipment was dismantled later in 2011. In Dec 2011, the National Government announced plans to reduce its shareholding in the four state-owned energy companies, Contact Energy, Genesis Energy, Meridian Energy and