Contact operates a diverse portfolio of electricity generation including renewable hydro power stations on the Clutha River in Central Otago, renewable geothermal plants around Taupo and three natural gas-fired power stations in Taranaki and Waikato.

(Read more about the different methods of generating electricity.)

Generating power from renewable resources

As New Zealand grows, so too does our demand for a strong, secure supply of electricity.

However, New Zealand increasingly needs more electricity generation which is both reliable and renewable. This can be a difficult combination to achieve.

Around 60 percent of New Zealand’s electricity is generated through large hydro power stations. Contact’s two large hydro dams on the Clutha River - the Clyde and Roxburgh power stations – have become iconic features of New Zealand’s sustainable use of renewable resources. Together, they harness the power of one of New Zealand’s largest rivers to provide around 10 percent of the country’s total electricity.

While hydro power stations and, increasingly, wind farms, can produce large amounts of clean, renewable electricity, they also depend on the weather – rain for the hydro power stations and wind for the wind farms. As a result they cannot produce ‘baseload’ electricity which is reliable and ‘always on’.

Many people might be surprised to know that the most reliable form of renewable electricity generation is, in areas like Taupo, literally right under our feet. Geothermal energy involves harnessing the heat from under the earth’s surface and using that heat and steam to generate electricity.

New Zealand has been a world-leader in the development of geothermal electricity generation, and Contact is New Zealand’s largest producer of geothermal electricity. Our three geothermal power stations are located at Wairakei, Ohaaki and Poihipi Road. Together, they provide New Zealand with around 5 percent of total electricity production. Geothermal is New Zealand's most reliable form of renewable generation, providing large amounts of baseload power regardless of the weather.

Keeping the lights on when the weather doesn’t play ball

Because both hydro and wind power depend on the weather, they need to be backed up by strong, flexible electricity generation that can be turned on when it is most needed – when the hydro lakes are low and when the wind doesn’t blow.

This critical back-up is provided by thermal generation – natural gas or oil in electricity generation plants. It is important as it provides very reliable electricity in large amounts. It can be turned on and off very quickly and can also provide around the clock ‘baseload’ electricity generation.

It is this thermal generation that keeps the lights on and the country running when the weather refuses to play its part.

All of Contact’s thermal generation plants run on natural gas.