Skip to main content

Engie advances geothermal exploration for Réunion Island energy independence

Engie’s Geothermal Ambitions in Réunion Island: A Turning Point for Energy Independence in Volcanic Territories

By:Robert Buluma

In a world increasingly defined by the urgency of energy transition, remote island territories stand at the frontline of both vulnerability and opportunity. The recent move by to secure a geothermal exploration permit in marks more than just another project milestone—it signals a potential transformation in how isolated regions harness their natural resources to break free from fossil fuel dependency.

This development, centered in the Cafres-Palmistes highlands, is not merely about drilling wells or building a power plant. It is about unlocking the immense geothermal promise hidden beneath volcanic landscapes, navigating environmental sensitivities, and setting a precedent for sustainable energy in island economies worldwide.


A Strategic Foothold in Volcanic Terrain

Réunion Island, located east of Madagascar in the Indian Ocean, is a geological marvel shaped by intense volcanic activity. Dominated by iconic formations such as Piton de la Fournaise—one of the most active volcanoes in the world—the island possesses the kind of geothermal conditions that energy developers dream of: high heat flow, fractured rock systems, and deep reservoirs of thermal energy.

It is within this context that Engie has been granted an exclusive exploration permit covering approximately 55 square kilometers. The designated zone includes the volcanic regions of Plaine des Cafres and Plaine-des-Palmistes—areas believed to host promising geothermal reservoirs.

For Engie, this is not just another exploration license. It is a calculated step into a high-potential yet complex environment where success could yield a power plant exceeding 15 MWe—enough to make a meaningful contribution to the island’s energy mix.


Why Geothermal Matters for Island Economies

Island territories like Réunion face a unique set of energy challenges. Their geographic isolation often makes them heavily dependent on imported fossil fuels, exposing them to volatile global energy prices and supply chain disruptions.

Currently, a significant portion of Réunion’s electricity is generated from imported fuels. This dependency comes with economic and environmental costs—high electricity tariffs, carbon emissions, and vulnerability to external shocks.

Geothermal energy offers a compelling alternative.

Unlike solar and wind, which are intermittent, geothermal provides baseload power—a constant and reliable source of electricity available 24/7. This makes it particularly valuable for islands, where grid stability is critical and storage solutions can be expensive.

If successfully developed, geothermal power on Réunion Island could:

  • Reduce reliance on imported fuels
  • Stabilize electricity prices
  • Lower greenhouse gas emissions
  • Enhance energy security

In short, geothermal is not just an energy solution—it is a pathway to sovereignty.


The Long Road to Approval

Engie’s journey to securing this exploration permit has been anything but straightforward. The initial application dates back to 2021, underscoring the lengthy and often complex regulatory processes associated with geothermal development.

By 2024, additional documentation had been submitted, pushing the project into a rigorous review phase led by environmental authorities. This stage focused heavily on assessing potential ecological impacts—a critical consideration given Réunion’s rich biodiversity and fragile ecosystems.

Authorities raised key concerns, including:

  • The need to avoid ecologically sensitive zones
  • Protection of drinking water resources
  • Minimizing surface disturbance during exploration

These are not trivial issues. Geothermal projects, especially in volcanic regions, must carefully balance resource extraction with environmental stewardship. Poorly managed developments can lead to groundwater contamination, land subsidence, or ecosystem disruption.

The fact that Engie has successfully navigated this phase suggests a level of technical preparedness and environmental commitment that regulators found acceptable.

However, it is important to note that the exploration permit does not grant permission for deep drilling or power plant construction. Those stages will require additional approvals, environmental impact assessments, and likely further public consultation.


The Science Beneath the Surface

At its core, geothermal energy relies on tapping heat stored beneath the Earth’s surface. In volcanic regions like Réunion, this heat is often closer to the surface and more accessible than in other geological settings.

The exploration phase will likely involve:

  • Geological and geophysical surveys
  • Temperature gradient measurements
  • Seismic imaging
  • Shallow exploratory drilling

These activities aim to answer fundamental questions:

  • How hot is the reservoir?
  • How deep is it located?
  • Is there sufficient permeability to allow fluid flow?
  • Can the resource sustain long-term energy production?

The answers to these questions will determine whether the project moves forward to full-scale development.


A 15 MWe Vision: Small but Powerful

At first glance, a 15 MWe power plant might seem modest compared to large-scale geothermal projects in countries like Kenya, the United States, or Indonesia. But for an island grid, this capacity is significant.

To put it into perspective:

  • It can power tens of thousands of homes
  • It provides stable baseload electricity
  • It complements intermittent renewables like solar and wind

Moreover, geothermal projects are often scalable. A successful initial plant can pave the way for expansion, potentially unlocking larger capacities over time.

For Réunion Island, even a 15 MWe plant could serve as a cornerstone of a diversified and resilient energy system.


Environmental Sensitivity: A Double-Edged Sword

Réunion Island is not just a geothermal hotspot—it is also an ecological treasure. Large portions of the island are designated as protected areas, including national parks and UNESCO World Heritage sites.

This creates a delicate balancing act.

On one hand, geothermal energy offers a clean alternative to fossil fuels, aligning with global climate goals. On the other hand, exploration and development activities must be carefully managed to avoid damaging sensitive ecosystems.

Key environmental considerations include:

  • Protecting endemic plant and animal species
  • Preserving water resources
  • Minimizing land disturbance
  • Managing noise and emissions during drilling

Engie’s ability to address these concerns will be critical not only for regulatory approval but also for public acceptance.


The Role of Policy and Governance

The involvement of the French Ministry of Energy highlights the importance of strong governance in advancing geothermal projects. Clear regulatory frameworks, environmental safeguards, and transparent approval processes are essential for balancing development and conservation.

France has been increasingly supportive of renewable energy initiatives, particularly in its overseas territories, where the benefits of energy independence are most pronounced.

The granting of this permit signals a willingness to explore geothermal potential while maintaining strict oversight—a model that could be replicated in other regions.


Albion and the Broader Geothermal Landscape

Engie is not the only player exploring geothermal opportunities on Réunion Island. Another French energy company, Albion, previously secured a five-year exploration permit for the Piton des Neiges site.

This parallel development suggests a growing interest in the island’s geothermal potential and raises the possibility of a broader geothermal ecosystem emerging.

Multiple projects could lead to:

  • Increased data sharing and geological understanding
  • Development of local expertise
  • Economies of scale in infrastructure and services

In essence, Réunion Island could evolve into a geothermal hub within the Indian Ocean region.


Lessons for Africa and Beyond

For countries like Kenya—already a global leader in geothermal energy—this development offers interesting parallels and insights.

Kenya’s success in harnessing geothermal resources, particularly in the Rift Valley, demonstrates what is possible when geological potential is matched with sustained investment and policy support.

Réunion Island’s journey, while different in scale, reflects similar themes:

  • Leveraging volcanic geology
  • Navigating environmental constraints
  • Building energy independence

For emerging geothermal markets across Africa, Southeast Asia, and Latin America, the key takeaway is clear: geothermal development is a long-term commitment that requires patience, expertise, and strategic vision.


Challenges Ahead

Despite the optimism surrounding Engie’s permit, significant challenges remain:

1. Resource Uncertainty

Geothermal exploration is inherently risky. Not all identified sites yield commercially viable resources.

2. High Upfront Costs

Exploration and drilling are capital-intensive, with no guarantee of success.

3. Regulatory Complexity

Multiple layers of approval can slow down project timelines.

4. Public Perception

Local communities must be engaged and convinced of the project’s benefits.

5. Environmental Constraints

Strict safeguards may limit where and how development can occur.

Overcoming these challenges will require a combination of technical innovation, financial resilience, and stakeholder collaboration.


The Bigger Picture: A Global Geothermal Renaissance

Engie’s move comes at a time when geothermal energy is experiencing renewed global interest. Advances in drilling technology, reservoir modeling, and enhanced geothermal systems (EGS) are expanding the boundaries of what is possible.

From superhot geothermal projects to lithium extraction from geothermal brines, the sector is evolving rapidly.

Réunion Island’s project, while conventional in scope, is part of this broader renaissance—a reminder that even smaller-scale developments can play a crucial role in the global energy transition.


A Vision of Energy Independence

Imagine a future where Réunion Island no longer relies heavily on imported fuels. Where electricity is generated from the heat beneath its own الأرض. Where energy costs are stable, emissions are low, and the grid is resilient.

This is the vision that geothermal energy makes possible.

Engie’s exploration permit is just the first step on this journey. But it is a significant one—a signal of intent, a commitment to innovation, and a recognition of the island’s untapped potential.


Conclusion: From Exploration to Transformation

The granting of a geothermal exploration permit to Engie in Réunion Island represents more than a bureaucratic milestone. It is the beginning of a process that could reshape the island’s energy landscape.

From the volcanic highlands of Cafres-Palmistes to the policy corridors of Paris, this project embodies the complexities and possibilities of modern energy development.

It is a story of:

  • Geological opportunity
  • Environmental responsibility
  • Technological ambition
  • Strategic foresight

As exploration progresses, the world will be watching. Success here could inspire similar initiatives across island territories and volcanic regions worldwide.

For now, the message is clear: beneath the surface of Réunion Island lies not just heat—but hope. 

Source: Port 1

Connect with us: LinkedIn, X

Comments

Hot Topics

Blowout at Cape Station: Fervo Energy’s First Major Crisis After Blockbuster IPO

Just weeks after a record-breaking IPO, the flagship project of the "geothermal unicorn" faces its first major operational crisis. By : Robert Buluma   Beaver County, Utah – The morning of May 27, 2026, began like any other at the Cape Station construction site in rural Utah. Workers for Fervo Energy, the newly public darling of the renewable energy world, were engaged in the complex task of drilling deep into the Earth’s crust to unlock what the company promised would be the future of 24/7 clean power. But by the afternoon, the routine had turned into a crisis. The site had experienced a blowout—an uncontrolled release of fluid or pressure from a well. For any energy company, a blowout is a serious matter. For Fervo Energy, which had just raised $1.89 billion in a blockbuster Nasdaq debut two weeks prior, it represents an immediate stress test of its technology, its safety protocols, and its $7.7 billion market valuation. While the well has since been contained and no injur...

Rodatherm Energy: The Refrigerant Gambit

By: Robert Buluma   Rodatherm Energy has done something no other geothermal startup has attempted at commercial scale: swapped water for refrigerant in a closed-loop system. The claim is 50% higher thermal efficiency than water-based binary cycles, achieved by circulating a proprietary phase-change fluid through a fully cased, pressurized wellbore. The company emerged from stealth in September 2025 with a $38 million Series A—the largest first venture raise in geothermal history. Lead investor Evok Innovations was joined by Toyota Ventures, TDK Ventures, and the Grantham Foundation. The engineering thesis is elegant. The execution risks are significant. This is an Alphaxioms examination of both. II. The Thermodynamic Distinction Every geothermal company you've covered moves heat using water or steam. Rodatherm moves heat using a fluid that boils and condenses inside the wellbore. In a conventional closed-loop water system (Eavor's model), water circulates as a single-phase liq...

The Heat Beneath Our Feet: How Canada’s First National Geothermal Roadmap Could Redefine Clean Energy

The Heat Beneath Our Feet: Canada Invests in First National Geothermal Energy Roadmap By: Robert Buluma   Image: The Eavor Wonder,  something amazing 👏  Calgary, Alberta – June 11, 2026 – In a move that signals a significant shift toward diversifying its clean energy portfolio, the Government of Canada has officially invested in its first national roadmap for deep geothermal energy. The announcement, made today by the Honourable Tim Hodgson, Minister of Energy and Natural Resources , marks a pivotal moment for a country better known for its oil sands and hydroelectric dams than for harnessing the heat of the Earth’s crust. With a conditional investment of $468,000 through Natural Resources Canada’s Energy Innovation Program , the government is backing the Canadian Deep Geothermal Roadmap project. Led by the Canadian Deep Geothermal Coalition and supported by the  Cascade Institute as the secretariat, this initiative aims to create a cohesive, evidence-based strate...

Mazama Energy Newberry Superhot Geothermal Breakthrough Reshapes Clean Energy

Mazama Energy’s Superhot Rock Vision Redefines Global Geothermal Power By Robert Buluma   The geothermal industry is entering a new era, and one company is pushing the boundaries of what was once considered technically impossible. Mazama Energy has ignited global attention after revealing extraordinary progress at its Newberry geothermal site in central Oregon, where it reportedly achieved temperatures of 331°C in an enhanced geothermal system environment. For an industry accustomed to operating within the 150°C to 300°C range, this milestone is more than impressive — it signals the possible beginning of a technological transformation capable of reshaping the future of clean baseload power. For decades, geothermal energy has quietly remained one of the most reliable renewable energy resources on Earth. Unlike solar and wind, geothermal power does not depend on weather conditions, sunlight, or seasonal variability. It delivers continuous electricity twenty-four hours a day, seven ...

"Below the Surface: How Baker Hughes is Drilling the 24/7 Clean Energy Solution"

Below the Surface: How Baker Hughes is Drilling the 24/7 Clean Energy Solution By: Robert Buluma   The geothermal era has arrived — and   Baker Hughes is holding the drill. While much of the energy world remains fixated on LNG exports and offshore wind, a quieter revolution is taking place beneath our feet. Baker Hughes (BKR) , the Houston-based energy technology giant, has assembled what may be the most comprehensive geothermal partnership network in the industry — positioning itself as the go-to industrial executor for next-generation geothermal power. In 2026 alone, the company has locked in strategic collaborations spanning three continents, from the deserts of Saudi Arabia to the outback of Australia and the high-heat basins of the American West. The common thread? Baker Hughes is applying a century of oil and gas drilling expertise to unlock geothermal energy at industrial scale — and the data center boom is providing the perfect market catalyst. The Strategy: "G...

The Retrofit Revolution: How GreenFire Energy Is Turning Abandoned Oil & Geothermal Wells Into Continuous Clean Power Without New Drilling

The Retrofit Revolution: How GreenFire Energy Is Unlocking Geothermal Power Without Drilling a Single New Well By: Robert Buluma   While much of the geothermal energy sector has been focused on breakthrough drilling techniques—deeper wells, hotter reservoirs, and complex engineered systems—a quieter revolution has been unfolding in the background. Instead of chasing entirely new subsurface frontiers, one company has chosen a radically simpler question: What if the answer was already in the ground? GreenFire Energy is advancing a retrofit-first geothermal strategy that targets one of the most overlooked opportunities in the global energy transition: existing wells that are underperforming, depleted, or completely abandoned. Rather than drilling new holes into the Earth, the company is reusing the infrastructure that already exists—turning stranded assets into continuous sources of clean, baseload electricity. This approach is not just technically elegant. It may also be one of ...

The XGS Energy Heat Sponge Solves Geothermal's Biggest Problem

The XGS Energy Heat Sponge Solves Geothermal's Biggest Problem I mage: A californian XGS well pad Imagine drilling a hole into the Earth’s hot crust  but instead of simply dropping in a pipe and hoping for the best, you paint the inside of that hole with a magic material that soaks up heat like a sponge soaks up water. Then you seal it, circulate a fluid, and generate clean, firm electricity  24/7, no fracking, no water consumption, no earthquakes. That’s not science fiction. That’s XGS Energy . While most of the geothermal world has been chasing fracked reservoirs or massive drilling rigs, XGS quietly built a prototype, ran it for over 3,000 hours in one of the harshest geothermal environments on Earth, and landed a 150 MW deal with Meta – enough to power tens of thousands of homes or a massive data center campus. This is the story of a technology that might be the most elegant, low-risk, and capital-efficient path to scalable geothermal power. Let’s dig in. Part 1: The Pro...

Sage Geosystems: Turning Underground Pressure Into 24/7 Power

Sage Geosystems : The Geothermal Startup That Turns Pressure Into Power By: Robert Buluma Most conversations about advanced geothermal circle around the same question: How do you extract heat from dry rock? Sage Geosystems started with a different question: What if the Earth could do most of the work for you? Based in Houston, Sage has quietly built a technology stack that treats the subsurface not just as a heat source, but as a pressure vessel. Their system captures heat and mechanical energy, stores energy underground like a battery, and uses a fraction of the surface pumping that conventional geothermal requires. This article focuses entirely on Sage , how their technology works, what makes it genuinely different, and where the blind spots still are. Part I: The Core Innovation , Pressure Geothermal Sage's foundational insight is simple but powerful: deep hot rock isn't just hot. It's also under immense natural pressure. Traditional geothermal systems ignore that pre...

Project Obsidian: Unlocking Superhot Geothermal Power from Deep Earth

Quaise Energy and the Dawn of Superhot Geothermal Power in Oregon By: Robert Buluma Inside Project Obsidian and the Future of Deep Earth Energy The global energy transition has long been defined by solar panels on rooftops, wind turbines across plains, and batteries reshaping grids. Yet beneath all these familiar technologies, another contender is quietly emerging—one that does not depend on weather, daylight, or even surface conditions at all. It comes from deep within the Earth itself, from rock so hot it behaves almost like a molten energy reservoir. That is the frontier where Quaise Energy is now operating. In Oregon, the company is developing what could become the world’s first superhot geothermal power plant under its ambitious initiative known as Project Obsidian . If successful, it could mark a fundamental shift in how humanity produces clean, continuous electricity—moving from shallow geothermal pockets to tapping heat sources several kilometers beneath the Earth’s surfac...

Supercritical Geothermal Energy Explained: The $60 Billion Future Power Source

Supercritical Geothermal Energy Explained: The $60 Billion Future Power Source By : Robert Buluma Beneath our feet lies a virtually unlimited source of clean, always-on power. Yet conventional geothermal energy—even with major recent advancements—barely scratches the surface, currently accounting for only about 1% of global electricity demand. The game-changing potential lies far deeper, where water reaches a mysterious fourth state known as supercritical. This is the frontier of supercritical geothermal energy, a technology poised to reshape the global energy landscape and attract multi-billion-dollar investments. What Is Supercritical Geothermal Energy ? Water in its familiar liquid, solid (ice), or gaseous (steam) states is just the beginning. When pressure and temperature exceed specific thresholds—approximately 22.1 MPa (over 200 times atmospheric pressure) and 374°C for pure water—the distinction between liquid and gas vanishes. This is the supercritical phase: a single, dense, h...