Assessing Geothermal Energy Resources in Nigeria for Sustainable Energy Development

Abstract Geothermal energy in Nigeria represents a promising renewable energy source capable of providing reliable baseload electricity and direct heat applications while supporting decarbonisation and net-zero objectives. Unlike solar and wind energy, which are intermittent by nature, geothermal systems provide a stable and continuous energy supply, making them ideal for integration into national power grids and industrial operations. Nigeria has several potential geothermal resources, including hot springs, sedimentary basins, and depleted hydrocarbon and abandoned oil and gas wells. Despite the presence of geological indicators and features in various parts of the country, geothermal energy development and deployment in Nigeria remains limited. This study investigates Nigeria's geothermal energy potential, focusing on the distribution of resources, the characteristics of the geology and reservoirs, and suitable energy conversion pathways and technologies in shallow and deep geothermal systems. The methodology is based on a comprehensive assessment and systematic analysis of the existing geothermal resources and their thermal characteristics, integrated with Heat in place (HIP) and Monte Carlo simulations. Geothermal resources are classified as shallow, deep, or associated with abandoned oil and gas wells, and each resource category is evaluated in terms of its geothermal energy potential and the suitability of available energy conversion technologies. The findings indicate significant geothermal resource potential in Nigeria, with estimated hydrothermal geothermal resources of approximately 430 MJ associated with thermal springs, 20 GJ from sedimentary geothermal systems, and 220 MW of potential energy recoverable from abandoned wells, based on Heat in place (HIP) and Monte Carlo simulations. Thermal springs and abandoned wells present immediate opportunities for low to medium temperature applications, such as direct heat use and small-scale energy systems. In contrast, sedimentary (deep geothermal) systems represent a longer-term prospect for electricity generation due to their greater development requirements and investment needs. The findings also highlight critical research gaps that must be addressed to support future geothermal development in Nigeria. Addressing these challenges will be essential for positioning geothermal energy as a key component of Nigeria's diversified renewable energy portfolio, thereby enhancing energy security, promoting sustainable economic development, and contributing to climate change mitigation efforts.