Geothermal steam from the Ohaaki Power Station near Taupō. Photo / Alan Gibson
Geothermal steam from the Ohaaki Power Station near Taupō. Photo / Alan Gibson
Land within Rotokawa Geothermal Reservoir near Taupō has been chosen as a preferred site for New Zealand’s first supercritical geothermal exploration, Regional Development Minister Shane Jones says.
He says design work is already under way to develop the first well at the site in the Taupō Volcanic Zone.
The Governmentannounced last week more than 20 leading global geothermal experts would explore the “significant energy potential” of the Central Taupō Volcanic Zone from October 1 thanks to $10 million of Government funding.
The draft strategy paper said “supercritical” geothermal technology – which involved drilling deeper into the Earth’s crust – could offer up to three times more energy than current geothermal energy.
In March, Jones met with mana whenua from around the Taupō Volcanic Zone to discuss the potential of the “abundant but underutilised” natural resource.
Exploration could be a ‘game changer’
In today’s statement, Jones said this early-stage exploration could help prove the viability of supercritical geothermal energy, which had the potential to deliver “several times the power output of conventional geothermal wells”.
“This groundbreaking work could be a game changer for securing New Zealand’s future energy needs.”
The Rotokawa site was chosen following extensive geological and geophysical study by Earth Sciences New Zealand, and risk assessments to confirm its suitability.
Jones said Tauhara North No.2 Trust was guardian of the Rotokawa geothermal resources and had “deep cultural and historical connection” to the area, including using geothermal energy for cooking, bathing, and healing.
A Memorandum of Understanding was signed between Tauhara North No.2 Trust, the Ministry of Business, Innovation and Employment, and Mercury NZ which operates the Rotokawa geothermal power station, to explore the potential of supercritical geothermal energy at the site.
Earth Sciences NZ was contributing technical and scientific expertise.
As part of the work, a multi-disciplinary design team comprising local and international experts, was also being assembled to lead work across regulatory approvals, design, risk assessment, geoscientific modelling, engineering, procurement, drilling and asset management.
The Coalition Government had committed up to $60m from the Regional Infrastructure Fund to support the development of the first well, with plans for two additional wells as part of a broader programme.
The first phases of the project included pre-feasibility work studies, well design, development of a business case and validation of the preferred site.
Drilling was expected to begin in 18 to 24 months.
Regional Development Minister Shane Jones. Photo / Mark Mitchell
Jones said three exploratory wells were the “minimum” needed to understand the energy resource.
He said drilling into supercritical zones meant going 1km to 3km deeper into the Earth and managing higher pressures and temperatures than current conventional generation.
“This is one of the most technically demanding frontiers in geothermal technologies and science.”
Jones said safely converting and commercialising supercritical geothermal energy was the next step.
“The Government is backing this groundbreaking project which aims to unlock transformative, clean, renewable energy over the long term to strengthen our energy security and be transformative for the country and internationally.”
