Joint Venture Chair, William Meek, said that during a planned outage for routine maintenance, inspections found that the turbine blades were being affected by geothermal fluids used to power the plant. The turbine was modified to allow ongoing operation, reducing operating capacity to about 95%.

"This shut means we can open up the turbine so that we can properly assess the issue to increase reliability of the plant through until permanent repairs can be made in about 15-18 months."

He said the maintenance outage would not have a material financial impact, with revenue losses mitigated by current wholesale market conditions. The current estimated repair and turbine blade replacement cost to the joint venture is expected to be about $15 million in FY2015.

About Nga Awa Purua:

Nga Awa Purua station commissioned March 2010, with rating of 138MW (above original design by 8MW)
Jointly owned: Mighty River Power 65% / Tauhara North No.2 Trust 35%
Plant availability since commissioning 96%, well above international benchmarks.