The Project Hayes wind farm Environment Court hearing has been abandoned until next year after opponents won the right to present new evidence.

Effectively this means all the expert witnesses for both Meridian Energy and appellant groups relating to landscape and visual effects as well as transmission might have to be recalled.

The new evidence relates to cumulative effects based on the Mahinerangi wind farm.

Judge Jon Jackson made his decision yesterday to grant the Maniototo Environmental Society an application for new evidence, vacating the continuation of the hearing in Dunedin, which was to restart on August 18.

The delay in the hearing was to give witnesses time to gather new evidence and exchange with the parties involved in the court proceedings.

Meridian Energy objected to the application, saying a further delay in the Resource Management Act process was not in the public interest, particularly when dealing with a project of that size "and when the country is crying out for investment in renewable electricity generation",' lawyer Andrew Beatson said on Tuesday.

Mr Beatson told The Southland Times yesterday, after the court had adjourned, it was looking more likely that the allotted time for the hearing wasn't going to be sufficient anyway.

"We are only halfway through our witnesses and there are 24 more to go" (in total), he said.

Meridian would naturally be disappointed the hearing had been delayed for so long, and he indicated the company would probably look at reviewing the decision.

"It's just one of those things," he said.

The company would now just concentrate on responding to the court's request for more evidence, on cumulative effects and energy efficiency, he said.

Save Central members, involved in a fundraising campaign for the environmental society's appeal, said it was "a great relief" that the application was granted.

Nobody was keen to comment on the record after Judge Jackson warned both parties about talking to the media while the hearing was still on.

Central Otago Mayor Malcolm Macpherson said without knowing the detail of the decision he did not want to comment on whether he thought the delay was necessary.

The hearing resumes on January 19, 2009.