By Efosa Taiwo

As Nigeria grapples with chronic energy shortages and a growing demand for clean, sustainable electricity, a new study by researchers at the Federal University of Technology Owerri is spotlighting an overlooked and underutilized solution: geothermal energy.

 

Presented at the Society of Petroleum Engineers (SPE) Nigeria Annual International Conference, the research estimates that just one geothermal reservoir beneath Nigerian soil could generate up to 74 megawatts (MW) of electricity—enough to power entire towns for decades.

In this interview with Nnamdi Francis Okeifufe, energy engineer and lead author of the study, he discussed the science behind this breakthrough, what it means for Nigeria’s energy security, and how the country can tap into its immense underground potential.

Excerpts:

Geothermal energy is still relatively unknown in Nigeria. Can you explain what it is and how it works?

Absolutely. Geothermal energy is a form of renewable energy that comes from the Earth’s natural internal heat. This heat originates from the planet’s core and moves upward through layers of rock and water. In areas where this heat is concentrated, we find geothermal reservoirs—essentially underground pockets of hot water or steam. To harness geothermal energy, we drill deep wells into these reservoirs and bring the heat to the surface. This heat is then converted into electricity using geothermal power plants. There are three main types: Dry steam plants, which directly use steam to spin turbines;

Flash steam plants, which convert high-pressure hot water into steam; And binary cycle plants, which use heat exchangers and a secondary fluid to generate electricity. Beyond electricity generation, geothermal energy can be directly used for heating buildings, supporting agricultural processes, and even powering small-scale industrial applications. It’s a clean, steady, and incredibly reliable source of energy—available 24/7, unlike solar or wind.

Why is geothermal particularly important for Nigeria at this point in time?

Nigeria is at a critical energy crossroads. Today, more than 85 million Nigerians lack access to reliable electricity, and many rural communities remain off the national grid entirely. Meanwhile, our power sector is overly reliant on gas and hydropower, both of which are vulnerable to external shocks like pipeline vandalism, water scarcity, and global fuel prices.

Geothermal offers a decentralized and consistent solution. It can help power remote areas, reduce pressure on the grid, and diversify our energy mix. Unlike fossil fuels, geothermal is carbon-neutral—aligning with Nigeria’s commitment under the Paris Climate Agreement and its target of 30 GW of renewable energy capacity by 2030.

Moreover, Nigeria already has geothermal indicators—Ikogosi Warm Springs in Ekiti, Wikki Springs in Bauchi, and other hot spots in the Niger Delta. The resource is there. What’s been missing is attention, investment, and policy focus.

Your recent study has created a lot of buzz. Can you walk us through the core findings?

Certainly. Our team, including Dr. N.C. Izuwa and Dr. Ngozi Nwogu, focused on estimating the quantity of usable geothermal heat in subsurface formations in Nigeria, specifically using data from abandoned oil wells in the Niger Delta. These wells provide a valuable source of thermal data, and they represent an untapped opportunity for geothermal retrofitting.

We applied a rigorous mathematical model using thermodynamic principles. First, we estimated the total heat in place, then accounted for losses during extraction—conduction, convection, and wellbore dissipation. What we found was remarkable: A single reservoir could yield 4.5 × 10¹⁷ joules of recoverable heat. Using a conservative thermal-to-electric conversion efficiency of 16%—which is standard for high-temperature systems—that translates to about 74 MW of electricity sustained over a 30-year period. Even more impressive were our recovery rates. Using a 1-inch diameter wellbore, up to 92% of the heat could be retrieved. With 2-inch and 3-inch diameters, efficiency remained high—84% and 76%, respectively. These are world-class figures that underscore the technical feasibility and commercial viability of geothermal energy in Nigeria.

What barriers currently stand in the way of developing geothermal energy in Nigeria—and where do the opportunities lie?

There are several key challenges, but each one also presents a corresponding opportunity:

Limited Geological Data. Right now, we don’t have comprehensive geothermal maps of Nigeria. That makes it hard to pinpoint high-potential zones with confidence. But this gap is also an open door for research and collaboration between universities, government agencies, and the private sector—especially in regions like the Sokoto, Chad, and Benue basins. Absence of a Policy Framework: There’s currently no specific regulatory framework or national strategy for geothermal energy. That’s a big hurdle. But it’s also a chance for legislators and energy regulators to lead with fresh policies that incentivize geothermal exploration, offer tax breaks or subsidies, and integrate geothermal into the national energy transition plan.

High Upfront Costs: Drilling and exploration are capital-intensive and come with geological risks. But we can learn from countries like Kenya and Iceland that have used public-private partnerships, risk-sharing models, and development finance to unlock geothermal investment.

Technical Capacity Gaps: We lack trained professionals in geothermal-specific fields like reservoir modeling and drilling. But this can be addressed through capacity-building programs, partnerships with global geothermal leaders, and the inclusion of geothermal studies in engineering curriculums.

Weak Infrastructure in Remote Areas: Many geothermal-rich areas are far from the national grid. That’s a challenge—but also an opportunity to deploy decentralized mini-grid systems to power rural communities, agricultural hubs, and off-grid industries. Competition from Cheaper Renewables: Solar and wind are currently cheaper to deploy. However, geothermal energy is non-intermittent, making it the perfect complement to renewables like solar, which only generate during the day. Together, they can create a stable, resilient clean energy mix.

What’s your vision for geothermal energy in Nigeria over the next decade?

I believe geothermal energy can become a pillar of Nigeria’s energy future if we move fast and smart. We’re not starting from scratch—we already have thermal gradients, legacy oil wells, and promising formations. What we need now is a bold national strategy, targeted investment, and a willingness to take calculated risks.

If Nigeria commits to exploring and developing its geothermal potential, we could not only provide clean, base-load power to underserved communities but also position ourselves as a regional leader in geothermal innovation—just like Kenya has done in East Africa. The heat is beneath us. It’s time to tap into it.