Predictive model for sustainable exploitation of geothermal resources in Africa: The case of Olkaria geothermal field

Geothermal energy is a crucial renewable resource for a sustainable future, especially in African nations cut by the Rift Valley, which holds vast untapped potential. However, high upfront costs and development risks remain key challenges. This study introduces a simplified model calibrated with real data from Kenya's Olkaria geothermal field. The model enables rapid preliminary assessments of both technical and economic performance, requiring minimal input data. Additionally, it incorporates a Life Cycle Assessment to evaluate environmental impacts, an aspect rarely explored in African geothermal studies. The research analyses various technological configurations, including Single Flash, Double Flash, and Organic Rankine Cycle (ORC) systems, aiming to improve efficiency without additional drilling. Findings show that integrating an ORC with existing flash systems can boost energy output by up to 20.1 %, with only a modest rise in the Levelized Cost of Electricity. Compared to the current Olkaria IV setup, hybrid systems demonstrated lower carbon emissions and reduced material resource use per energy output. Results confirm that ORC integration offers the most sustainable pathway for developing high-temperature geothermal resources in the East African Rift. This approach balances energy efficiency, economic feasibility, and environmental impact, providing valuable guidance for future power plant development in regulatory-constrained settings. This work is fully consistent with the objectives of Sustainable Development Goals (SDG) 7 and 13. • Developed a simplified model for geothermal feasibility with minimal data • Applied to Olkaria IV, assessing Flash and ORC upgrades via LCOE and LCA • ORC integration proved most sustainable, balancing output, cost, and impact.