Ohaaki Geothermal Power Station - Renewing Resource Consents Comparison with Greenfield Development

Abstract

The resource consents authorising the operation of Contact Energy’s Ohaaki Geothermal Power Plant, located in New Zealand, approximately 26 km north east of Taupo Township, were due to expire on 31 October 2013. To enable continued operation of the plant applications for new consents are required to be lodged 6 months before the existing consents expire, i.e. by 30 April 2013, Applications were lodged on 10 April, a hearing held in September and consents granted in November 2013. The challenges of renewing consents for an existing power plant, compared with consenting a ‘greenfield’ proposal, are explored, including costs and time frames. Determination of the baseline for assessing the effects of past and proposed future operations is addressed. Key issues for the consenting process are, the impact the development and operation of the power plant has had on the relationship between the tangata whenua and their ancestral lands and taonga, sustainable capacity of the reservoir, subsidence, water takes and discharges from and to the Waikato River, and discharges of separated geothermal water to the Waikato River. Technical assessment of effects reports to support the applications include, reservoir modelling, sustainability, subsidence, surface and shallow geothermal effects, groundwater effects, Waikato River environment, terrestrial ecology, archaeology, air quality, and wetland mitigation.