“Contact is proud to be associated with a positive new addition to New Zealand’s electricity generation from renewable sources,” Barrett said.

“Geothermal energy makes an important contribution to national electricity, with the potential to double over the next 10 years.”

The facility could supply an additional 15,000 homes from the binary plant’s renewable geothermal energy, according to Barrett.

The currently 450MW of geothermal capacity in New Zealand, supplied around 7% of the country’s electricity needs, and that figure could double over the next decade.

The binary plant was part of Contact’s on-going commitment to improving the efficiency of its existing operations. It increased Wairakei’s output by about 10% but required no more draw-off from the steam field.

Barrett, who returns to his native US at the end of this month, said Contact was also making good progress on the rest of its 100MW program of new generation.

It was completing a program of drilling four new geothermal production wells at the nearby Te Mihi steam field that was expected to add a further 25MW of generation capacity. As well, it was to start drilling new geothermal wells at Ohaaki by November to add another 14MW to existing plant there.

Contact had also recently added 10MW of capacity to its gas-fired Taranaki Combined Cycle (TCC) power station at Stratford. In adition, it expected by the end of the year to have added another 12MW to its gas-fired Otahuhu B station in south Auckland.

Contact contributes about 66% of all geothermal power generated in New Zealand from its central North Island stations at Wairakei, Poihipi and Ohaaki.