ABSTRACT
Historically, reservoir engineering as a discipline has been primarily focused on the hydrocarbon exploration and production sector, but it is experiencing a seismic shift that resonates with the global transition to cleaner energy systems. Reservoir engineering is being revamped to support a net-zero world, from maximising the potential of geothermal energy, hydrogen storage, carbon capture and storage (CCS), and subsurface analytics for energy storage. This article looks at the shift from traditional oil petroleum engineering to low-carbon and alternative energy and what this impetus means for the engineer, the industry and ultimately global energy security.

INTRODUCTION
A Necessary Evolution
According to the International Energy Agency, more than 80% of new capacity additions are anticipated to come from renewables by 2030, and oil consumption is forecast to reach its maximum around the mid-2030s under existing policy interventions (IEA, 2023). Reservoir engineers who were previously essential to the oil industry for enhancing oil recovery will face a paradigm shift as the main players to develop and harness carbon-neutral technologies.
It is not a transition of replacement. Reservoir engineers have decades of experience modeling these complex subsurface systems, and this can be directly applied to newer energy sectors such as CCS, geothermal energy, and hydrogen storage.

Carbon Capture and Storage: Turning Liability Into Asset
CCS is one of the most straightforward applications of reservoir engineering knowledge in the low-carbon space. This is the permanent storage of CO₂ in geological formations deep underground, which is strikingly similar to the process of enhanced oil recovery (EOR).
Tasks such as Modeling CO₂ plume migration, cap rock integrity assessments, and modeling long-term storage viability are technical functions that depend on existing reservoir simulation technology. Schlumberger’s Petrel and CMG’s GEM programs are currently being adapted for modeling the injection of CO₂ (SPE, 2023).
For example, Quest CCS in Alberta, Canada, has captured and stored more than 8 million tons of CO₂ since 2015 as part of their oilfield operations and technologies (Shell, 2024). Also, Nigeria’s carbon management policies are already looking at abandoned oil reservoirs in Niger Delta as possible sites for storage, which represents a potential synergy to be sought by local reservoir engineers.

Geothermal Energy: Tapping Into the Earth’s Heat
Geothermal energy converts heat from below ground formations into electricity and is a renewable base-load technology. Geothermal isn’t variable like wind and solar, and provides a helpful resource when trying to create a stable energy mix.
Reservoir engineers are key in the development of geothermal projects as they design the wells, estimate thermal recoverability, and control the subsurface pressure regime. Methods of petroleum geomechanics, such as well log analysis and prediction of production rates, apply seamlessly to geothermal applications.
While countries such as Iceland and Kenya are world leaders in the utilization of geothermal energy, Nigeria and other countries in sub-Saharan have been investigated and confirmed to have geothermal energy potential, particularly the Benue Trough and the Chad Basin areas (Oladeji et al., 2021). This could be an opportunity for local energy innovation in Africa, as local exploiting indigenous technologies to solve our climate and access challenges.

Hydrogen Storage in Subsurface Reservoirs
Hydrogen has increasingly come to be seen as fundamental to the global energy transition. But when made using renewable electricity, or “green hydrogen”, it becomes a clean fuel source which has the potential to decarbonize hard-to-decarbonize industries such as shipping, steel, and aviation.
The storage of hydrogen is still a bottleneck. Underground hydrogen storage (UHS) in formations like salt caverns, depleted gas fields, and aquifers is beginning to be considered as a possibility. Here too, the reservoir engineers, trained to understand porosity, permeability and pressure regimes, lead the way.
According to research from the Lawrence Livermore National Laboratory (LLNL), “porous formations could store tens of millions of cubic meters of hydrogen with proper sealing structures and integrity assessment” (LLNL, 2022). The petroleum industry already has significant expertise in multiphase flow modeling, gas dispersion simulations, and integrity monitoring, all of which are critical in this new frontier.

A Redefined Professional Identity
With the advancement of the reservoir engineer, professional identity must also advance. Under a carbon-constrained world, the old job description of “recover as much hydrocarbons as possible” is no longer good enough. Reservoir engineers of the future will need to be aware of and have a working knowledge of regulations and carbon accounting in addition to the environmental impacts of subsurface operations more broadly.
This should become a part of education again. Hybrid programs combining traditional petroleum topics with teaching on the dynamics of geothermal systems, carbon capture and storage, Modeling, and hydrogen behaviour in porous media are being introduced into universities and industry training programs.
Trade organizations such as the Society of Petroleum Engineers (SPE) have also adjusted, providing certification programs and technical sessions on the energy transition. One program that has started fairly recently, with the aim of bringing petroleum engineering in sync with sustainable development, is the SPE Gaia Program (SPE Gaia, 2023).

Navigating Challenges with Multidisciplinary Approaches
The opportunity is evident, but it is not without difficulty. Injecting co2 or storing hydrogen underground also poses a set of new regulatory, environmental, and technical challenges. Other areas of concern are subsurface containment, induced seismicity, and monitoring infrastructure that need intelligent multi-disciplinary solutions.
The reservoir engineer must no longer work in a vacuum. Collaboration with geochemists, environmental scientists, politicians, software engineers, and others are now necessary. A McKinsey report highlights this saying, “agile, interdisciplinary teams are more capable of realizing value in low-carbon opportunities” (McKinsey, 2023).
This is a reflection of the larger trend of moving from isolated oilfield operations to integrated energy value chains where data, sustainability, and adaptability converge.

CONCLUSION
Rather than becoming obsolete due to the green energy movement, reservoir engineers are finding new and innovative ways to become relevant again. As custodians of the underground, they are uniquely positioned to allow scaling of low-carbon technologies that depend on expertise on the subsurface.
For a country like Nigeria and Africa in general where the petroleum industry has historically driven national economies, this becomes both an opportunity and a necessity. This must include investments in building capacity, research and development, and smaller scale projects locally, to ensure African talent is centrally involved in the global clean energy transition.
As energy is evolving, so must our conception and training, deployment and respect for reservoir engineers. Instead of chasing barrels, the new frontier is to build bridges – to sustainability, to resilience and to the future of energy.

AUTHOR
Lymmy Ogbidi is a Reservoir Engineering Solution Lead, SLB, United Kingdom

REFERENCES
International Energy Agency (IEA). (2023). World Energy Outlook 2023.
Society of Petroleum Engineers (SPE). (2023). Digital Transformation & Energy Transition Resources.
Shell Canada. (2024). Quest Carbon Capture and Storage Project.
Oladeji, O., et al. (2021). Geothermal Energy Potential in Nigeria. Nigerian Journal of Renewable Energy.
Lawrence Livermore National Laboratory (LLNL). (2022). Subsurface Hydrogen Storage Studies.
McKinsey & Company. (2023). The Role of Multidisciplinary Teams in the Energy Transition.
Society of Petroleum Engineers – Gaia Program. (2023).