Mijnwater starts drilling for new heat source on Terhoevenderweg in Heerlen New source expands Parkstad’s district heating and cooling network Mijnwater has started drilling work for a new heat source at Terhoevenderweg in Heerlen, marking another important step in the expansion of its sustainable heating and cooling network in Parkstad. After a period of preparation, work began this week and is expected to continue for three to four weeks. Because the operation must be completed safely and efficiently, the drilling is taking place 24 hours a day, seven days a week. The project is part of Mijnwater’s broader effort to strengthen a low-carbon energy system for the region. The new source will tap warm groundwater in a former mine passage deep underground and feed that energy into the company’s network. For Heerlen and the surrounding area, this means further development of a district energy system that draws value from the region’s mining past while supporting a more sustainable energy ...
Todd Energy Selected to Drill New Zealand’s First Superhot Geothermal Well Near Taupō: Unlocking “Energy on Steroids” for a Renewable Future
By: Robert Buluma
In a landmark announcement that could reshape New Zealand’s energy landscape, Todd Energy has been named the preferred lead contractor to drill the country’s first exploratory superhot — or supercritical — geothermal well. The pioneering project, located within the Rotokawa Geothermal Field near Taupō in the heart of the Taupō Volcanic Zone (TVZ), marks a bold step into uncharted subsurface territory.
Drilling is slated to begin around mid-2027, targeting depths of 5 to 6 kilometres — nearly double the depth of conventional geothermal wells. If successful, this well could unlock a massive untapped renewable resource capable of delivering “energy on steroids,” as described by project chair and former Trade and Climate Change Minister Tim Groser.
The news, released on 11 March 2026 by the Ministry of Business, Innovation and Employment (MBIE), has been warmly welcomed by the industry. Energy Resources Aotearoa Chief Executive John Carnegie highlighted Todd Energy’s selection from four highly skilled applicants as a testament to New Zealand’s homegrown expertise. “Todd Energy brings its own rig, a fully New Zealand-based workforce and an established local supply chain,” he said. “That kind of readiness reflects the depth of capability our energy sector has developed over decades.”
This isn’t just another drilling project. It represents the next frontier in geothermal innovation — one that could power New Zealand three times over with clean, baseload renewable energy. In this in-depth blog post, we explore the science, the stakes, the players, the challenges, and the enormous potential of superhot geothermal energy. Buckle up: this is the story of how New Zealand is once again positioning itself as a global pioneer in harnessing the Earth’s heat.
What Exactly Is Superhot (Supercritical) Geothermal Energy?
To understand why this announcement is generating such excitement, we first need to dive into the science. Conventional geothermal energy — the kind that already supplies around 18% of New Zealand’s electricity — relies on hot water or steam reservoirs typically found at depths of 1 to 3.5 kilometres and temperatures of 250–350°C. These systems drive turbines to generate reliable, 24/7 power with minimal emissions.
Superhot geothermal, however, operates in an entirely different realm. When water reaches temperatures above 374°C and pressures exceeding 218 bar (roughly 3,000 metres of water depth equivalent), it transitions into a supercritical fluid. In this state, water no longer behaves as distinct liquid or gas phases — it becomes a dense, highly energetic “superfluid” with extraordinary heat-carrying capacity.
The advantages are staggering. Supercritical fluids can transfer heat far more efficiently than conventional geothermal brines. Industry estimates suggest a single superhot well could produce 5–10 times more power than a standard well, requiring far less fluid volume per megawatt generated. In New Zealand’s unique geology, scientists believe superhot resources could deliver up to three times more energy than today’s systems.
Project chair Tim Groser captured the excitement perfectly: “The science tells us that supercritical — also known as ‘superhot’ — geothermal is energy on steroids.” The extreme conditions also bring challenges: corrosive chemistry, immense pressures that can crack steel casings, and temperatures hot enough to melt conventional drilling equipment. But the rewards justify the risk.
New Zealand’s TVZ is uniquely suited for this quest. The zone’s thin crust and active volcanism allow superhot fluids to exist at relatively “shallow” depths of 5–6 km — accessible with today’s technology. Government research through Earth Sciences New Zealand (formerly GNS Science) has pinpointed the Rotokawa reservoir as the prime location with the highest probability of intersecting these prized resources.
This isn’t speculative fantasy. Global pioneers in Iceland have already proven the concept through the Iceland Deep Drilling Project (IDDP). We’ll return to those lessons later, but the takeaway is clear: superhot geothermal isn’t science fiction — it’s the next evolution of a technology New Zealand helped invent.
New Zealand’s Geothermal Legacy: From Wairakei to World Leadership
New Zealand has been at the forefront of geothermal development for nearly 70 years. The Wairakei Power Station, commissioned in 1958, was the world’s second commercial geothermal power plant and the first to use flash-steam technology on a large scale. At the time, it was a daring experiment that put New Zealand on the global energy map alongside Italy’s Larderello field.
Today, the country boasts approximately 1,259 MW of installed geothermal capacity (as of year-end 2025 figures). This represents one of the highest per-capita geothermal contributions worldwide and supplies a consistent 17–18% of national electricity demand. Fields across the TVZ — including Ngatamariki, Kawerau, Rotokawa, and Tauhara — power homes, industries, and even direct-use applications like greenhouse heating and tourism.
Mercury Energy operates two major plants at Rotokawa: the original Rotokawa station and the larger Ngā Awa Pūrua (also known as NAP) plant. These facilities already harness conventional resources from the same reservoir now targeted for superhot exploration. The new well will sit alongside existing infrastructure, minimising surface footprint and leveraging decades of reservoir data.
The government’s commitment to this project builds on that legacy. In September 2025, the Rotokawa site was officially selected as the preferred location. Funding includes up to $60 million from the Regional Infrastructure Fund plus an additional $10 million from the New Zealand Endeavour Fund. The project is managed through MBIE’s Kānoa – Regional Economic Development & Investment Unit in partnership with Earth Sciences New Zealand, the Tauhara North No.2 Trust (representing local iwi landowners), and Mercury.
This collaboration exemplifies the “just transition” philosophy: using existing energy sector skills — rather than discarding them — to accelerate renewables. As John Carnegie noted, New Zealand’s challenge isn’t shutting down one fuel source before alternatives are ready; it’s leveraging decades of drilling and reservoir management expertise to unlock the next generation of clean power.
Project Details: Depths, Timelines, and a Three-Well Programme
The superhot project is deliberately ambitious yet phased for success. Todd Energy’s role as lead contractor involves end-to-end responsibility: drilling, safety management, subcontractor coordination, and planning in an ultra-high-risk environment. Negotiations on final contract terms are now underway following the “preferred contractor” designation.
Key technical parameters:
- Target depth: 5–6 km (conventional wells rarely exceed 3 km)
- Expected bottom-hole temperatures: exceeding 400°C
- First of three planned wells to build knowledge and de-risk the resource
- Start date: mid-2027
- Site: A precisely pinpointed location within the Rotokawa reservoir identified by scientists as having the best chance of intersecting superhot fluids
The well will encounter progressively harsher conditions: increasing pressure, corrosive gases (including hydrogen sulphide and carbon dioxide), and thermal stresses that demand advanced materials and real-time monitoring. Todd Energy’s own “Big Ben” drilling rig — a proven workhorse — will be deployed, supported by a fully Kiwi workforce and local supply chain. This domestic focus not only reduces logistical risks but also delivers broader economic benefits to regional communities.
If the first well successfully flows superhot fluids, it will provide critical data on reservoir permeability, fluid chemistry, and power potential. Subsequent wells will test different completion techniques and scaling mitigation strategies. Success here could trigger commercial-scale development, transforming the TVZ into a supercritical powerhouse.
Todd Energy: Decades of Expertise Meet Future Ambition
Todd Energy is no newcomer to the energy game. Part of the family-owned Todd Corporation, the company traces its roots to 1929 when it became New Zealand’s first indigenous oil company. From early automobile and gasoline marketing ventures, Todd evolved into a major player in natural gas exploration and production.
Landmark achievements include the 1959 discovery of the Kapuni field (in joint venture with Shell and BP) and the massive offshore Maui field. These developments provided affordable local energy that powered New Zealand’s post-war growth. Over decades, Todd built specialised drilling capabilities across natural gas and geothermal projects in New Zealand and Australia.
Today, as the sector transitions, Todd is diversifying aggressively while maintaining its core strengths. The company’s track record of delivering complex drilling campaigns on time and on budget was a decisive factor in its selection. Tim Groser praised Todd’s “comprehensive project management and technical teams, drilling ancillary services, established safety systems, and transparent commercial structure.”
Bringing its own rig and local workforce isn’t just practical — it’s symbolic. It demonstrates that New Zealand’s traditional energy players are not obstacles to the renewable future; they are essential enablers. Todd’s involvement ensures the project benefits from institutional knowledge of TVZ geology, regulatory navigation, and community engagement — particularly important given the partnership with the Tauhara North No.2 Trust.
Technical Challenges: Drilling into the Earth’s Furnace
No one underestimates the difficulty ahead. At 5–6 km, drill bits must withstand temperatures that would destroy standard equipment. Pressures approach those found in deep oil wells, while corrosive fluids can eat through steel casings within months. Thermal cycling during drilling and testing creates immense stresses.
Lessons from Iceland’s IDDP project are instructive. In 2009, IDDP-1 in Krafla unexpectedly hit magma at just 2.1 km, producing superhot steam at 450°C with a theoretical output of up to 36 MW — five to ten times a conventional well. The well ultimately closed due to surface valve failures and scaling issues. IDDP-2 in Reykjanes reached 4.6 km in 2017, encountering supercritical conditions near 426–600°C before casing failure limited access.
New Zealand teams are actively learning from these experiences. Advanced metallurgy, real-time fibre-optic temperature sensing, and improved well-completion designs are all in play. Earth Sciences New Zealand’s research programme is developing predictive models of superhot reservoir behaviour. International partnerships will likely accelerate technology transfer.
The risks are real, but so are the mitigations. Todd Energy’s proven safety systems and the government’s staged funding approach provide buffers. Failure is possible — but even partial success will yield invaluable data for future attempts.
Global Context: Iceland Leads, New Zealand Follows
Iceland’s IDDP programme remains the gold standard. After IDDP-1’s dramatic magma encounter and IDDP-2’s supercritical breakthrough, the country is accelerating IDDP-3 with government backing. A single superhot well there could theoretically supply power for thousands of homes with a fraction of the surface infrastructure required by wind or solar farms.
Other nations — including the United States, Japan, and Kenya — are watching closely. New Zealand’s project benefits from this global momentum while leveraging our unique advantage: the TVZ’s accessible superhot resources. If Rotokawa delivers, New Zealand could export not just electricity but expertise and technology to the world.
Economic, Environmental, and Social Wins
The potential upside is enormous. Environmentally, superhot geothermal offers near-zero emissions baseload power — perfect for complementing intermittent renewables like wind and solar. Economically, successful development could create hundreds of high-skilled jobs in drilling, engineering, and operations. Regional economies around Taupō would benefit from investment and long-term royalties to iwi landowners.
On a national scale, the resource could displace fossil fuel imports, enhance energy security, and support decarbonisation targets. Imagine powering heavy industry, data centres, or even green hydrogen production with Earth’s heat. The $70 million+ public investment is a calculated bet on a high-return future.
Socially, the project emphasises partnership. Collaboration with Tauhara North No.2 Trust ensures mana whenua voices shape development, respecting cultural values tied to the whenua.
Looking Ahead: A Supercritical Horizon
The selection of Todd Energy is more than a contract award — it’s a statement of confidence in New Zealand’s energy future. As drilling rigs mobilise in 2027, the eyes of the world will be on Rotokawa. Success could trigger a wave of superhot development across the TVZ, cementing our position as geothermal innovators for the 21st century.
Challenges remain. Technical hurdles, community engagement, and regulatory frameworks must evolve. But the foundation is solid: world-class geology, proven expertise, government commitment, and private-sector drive.
New Zealand was a geothermal pioneer in the 1950s. With Todd Energy leading the charge into superhot territory, we’re poised to lead again. The Earth is offering us “energy on steroids.” The question is no longer whether we can harness it — but how quickly we can scale the opportunity.
This project reminds us that the transition to 100% renewable energy isn’t about abandoning the past; it’s about building on it. Deep beneath the Taupō landscape lies a resource that could power our nation sustainably for generations. Todd Energy, MBIE, Mercury, and their partners are about to unlock it.
Watch this space. The geothermal revolution is heating up — literally.
Source: New Zealand Government
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