Ngatamariki Geothermal Exploration

Ngatamariki, New Zealand
Tauhara North No. 2 Trust

Dan Hoyer managed the development of the exploration and drilling program for three exploratory wells in New Zealand. He also developed the procurement strategy, budget, and schedule and implemented the exploration program. Dan’s team successfully retrieved cores and logged and tested the wells. The project proved the commercial viability of a new resource area of about 7 square kilometres. The three wells were approximately 3,000 metres deep and drilled within budget and schedule requirements. Dan led the peer review for the 30-year development plan, including geothermal reserves estimates, makeup drilling schedule, and operation and maintenance budgets, to support the financial model. The $475 million project was approved by the Tauhara North No. 2 Trust and Mercury’s Boards. Construction commenced in July 2011 and was completed September 2013. Today, Ngatamariki is a commercially successful binary power plant with an installed capacity of 82 megawatts (MW) and is the largest binary power plant in the world. The plant is supplied by three production wells and four injections wells with dry cooling resulting in zero carbon emissions. The station normally runs 24 hours a day, 7 days a week and produces 700 gigawatt hours of electricity annually.

1. Preliminary Reconnaissance and Surface Exploration
2. Drilling Exploration
3. Feasibility Study