Geothermal plant game-changer for region

One of Top Energy's two geothermal power plants at Ngawha. Photo / Peter de Graaf

A $300-million geothermal power station expansion near Kaikohe could start producing electricity just as three fossil-fuel power plants are shut down further south.

Lines company Top Energy was this week given a green light to build two new geothermal power plants at Ngawha Springs, boosting its output from the current 25MW to 75MW - more than the Far North's peak demand of 70MW. The project will make the Far North a power exporter and, thanks to surplus heat and steam, could attract industries such as milk and timber processing to an area starved of jobs.

Top Energy chief executive Russell Shaw welcomed the consents granted, with a raft of conditions, by an independent panel of commissioners on Tuesday. He was still studying the 122-page consent document but had yet to find any conditions that caused him concern. Depending on electricity price forecasts, construction could start in 2017, with the first plant operational in mid-2019 - just as 1000MW of coal and gas-fired power plants were due to close in Huntly and Auckland.

"So we're really keen to replacethat with clean, green energy. It means we'll be self-sufficient with renewable energywith the potential to bring more industry into the district," Mr Shaw said.

One of the conditions is that the new plants will be built three years apart to allow monitoring of any changes in the geothermal field or nearby hot pools. Top Energy had sought a two-year gap; the Parahirahi C1 Trust, which owns land at Waiariki hot pools and objected to the proposal, wanted five years.

Top Energy also has to fund a peer review panel, will have to consult a kaitiaki adviser appointed by the Parahirahi C1 Trust, and set up a monitoring system to ensure culturally importantflora and fauna are protected. The consent also places limits on changes in water temperature and composition at the springs.

Far North Mayor John Carter said news the expansion was set to go ahead was "fan-bloody-tastic".

"This is huge for the Mid North, for all of Northland. It means we can look forward to being totally independent for power and even became a power exporter," he said.

Regional councillor Dover Samuels said the expansion could change the face of Kaikohe and especially Ngawha. Surplus heat from a Central Plateau geothermal power station ran a prawn farm and Maori-owned dairy factory, and there were also possibilities for processing timber grown in the area.