Last week Energy Minister Trevor Mallard said he was adopting a commission recommendation that the gas pipeline services of major network companies Vector and Powerco be regulated.

This week Unison said it had failed to gain a High Court injunction stopping the commission from publishing an intention to declare control of the Hastings-based company.

But chief executive Ken Sutherland said Unison – New Zealand’s fourth largest electricity lines company – would challenge that High Court decision in the Court of Appeal.

The commission effectively froze Unison’s lines charges between August 2001 and April 2004 as it had said Unison was in breach of the commission's regulatory regime based on price and quality thresholds.

Sutherland said Unison’s charges had been one of the lowest in the country and were not sustainable. His company had raised its prices twice during that period, in April 2002 and March 2004, and they were now just under the national average.

Unison was seeking the injunction to protect its position before a judicial review - which challenged the entire thresholds regulatory regime - was heard in the High Court in October.

If the commission decided to impose direct control on Unison, the Hastings firm would be the first electricity network company in the country to come under its influence.

Sutherland also said Unison had applied for an exemption to the Electricity Industry Reform Act – which prohibited network companies owning and operating any significant generation – to allow it and Tasmanian partner Hydro-Electric Corporation to build a 150MW wind farm in Hawke's Bay.

Unison would soon apply for the necessary resource consents so it could start building the wind farm next year.