Techno-economic assessment and potential of geothermal energy in Bangladesh for mitigating the energy crisis: A critical review

Geothermal energy, sourced from the Earth's internal heat, offers a sustainable and reliable alternative to conventional energy systems. Approximately 80% of this geothermal heat originates from the decay of radioactive elements, while the remaining portion comes from gravitational binding energy. This energy is accessed via geothermal reservoirs, providing a constant, base-load power generation source. In Bangladesh, the Bengal Basin's favorable geological conditions and tectonic activity suggest significant geothermal potential. Subsurface temperatures, ranging from 45.7 °C to over 150 °C, make it a promising location for geothermal power production. This study assesses the techno-economic feasibility of geothermal energy in Bangladesh, focusing on both high- and low-temperature resources. Key regions such as Barapukuria and the western Foreland Shelf exhibit geothermal gradients conducive to electricity generation. A comprehensive review of over 150 relevant research articles and geothermal energy resources was conducted to evaluate the technological and economic aspects of geothermal power. Techno economic assessment employs standard discounted cash flow analysis over a defined project lifetime, incorporates national resource data and cost assumptions, and uses the Levelized Cost of Energy (LCOE) as the primary financial metric to analyze and compare development scenarios. Various technologies, including flash steam, binary cycle systems, and enhanced geothermal system (EGS), are explored for their potential application based on the region's resource characteristics. Direct-use systems, such as geothermal heat pumps for building heating and cooling, are also considered. The techno-economic analysis suggests that geothermal plants in Bangladesh could generate up to 1000 MW of electricity from 100 to 150 wells, covering an area of 1000-15,000 ha, with a production cost of just 0.04-0.05 USD per kWh. The long-term reduction in fuel costs makes geothermal energy economically competitive with traditional energy sources, offering a sustainable solution to Bangladesh's energy challenges. While the geothermal industry in Bangladesh is in its early stages, further exploration and pilot projects will be crucial to unlocking the full potential of this resource, contributing to energy diversification and reducing greenhouse gas emissions as the country transitions to a greener, more sustainable energy future.