Iwi concerns block power plan

By TONY GEE

Far North power company Top Energy is reviewing a Northland Regional Council decision to refuse the company's application to take additional fluid from the Ngawha geothermal field to power station expansion.

Ngawha Geothermal Resource Company, a subsidiary of Kaikohe-based Top Energy, sought consent from two councils to take and reinject up to 775,000 tonnes of geothermal fluid a month, or about 25,000 tonnes a day, in the field.

The extra volume would have allowed Top Energy to expand its Ngawha geothermal station from its 10MW output to 25MW in a multi-million-dollar project.

At present, the company extracts and reinjects about 10,000 tonnes of geothermal fluid each day.

In a decision yesterday, a three-member joint hearings committee of the regional and Far North District councils said there were concerns about the potential effects an expanded power station could have on Ngawha Springs, east of Kaikohe.

The springs are the only geothermal field in the region, which the committee said were a taonga (treasure) of Ngapuhi iwi and local Maori.

There was no evidence to suggest that an expanded plant would not lead to significant changes to the geothermal resource and in particular the Ngawha Springs, although this was disputed by Top Energy.

"Any significant changes to the pool temperature, flow or chemical composition due to the [fluid] extraction would have a significant adverse effect on cultural and spiritual values of local iwi," the committee said.

Consents were approved, however, to allow the existing power station to continue working for the next 15 years.

The company has also been given permission to test a proposal to inject extra fluid into the Ngawha geothermal reservoir to maintain pressure in the reservoir.

"Information from this trial is necessary for full consideration of the effect of this or any expansion project on the geothermal reservoir and the Ngawha Springs," the committee said.

Top Energy chief executive Roger de Bray said the company's submissions contained extensive research, geothermal field monitoring and data modelling supporting its view that the springs would not be adversely affected beyond natural variations.

"No evidence was produced by opponents to suggest that any such changes would in fact take place," he said.

Concerns about the security of electricity supply were behind the fact that submissions in favour of the expanded station outnumbered those opposed by 10 to 1, Mr de Bray said.

Additional power generation was a serious issue for the whole country.

The company is reviewing the decision and will decide on any further action within the 15 working days allowed for an appeal.