ABSTRACT
This chapter explores geothermal energy systems, highlighting their potential for sustainable energy production and examining the challenges of harnessing geothermal resources in diverse geographical settings. It begins by characterizing geothermal energy as a resource derived from the Earth’s internal heat, sustained by a combination of primordial heat, radiogenic decay, and gravitational differentiation. The chapter delves into the Earth’s thermal gradients and heat flux, emphasizing regional variations caused by geological and tectonic factors.
The discussion transitions to geothermal systems, detailing their key components: heat sources, reservoirs, and geothermal fluids. Systems are classified by temperature (low, medium, high), fluid state (liquid- or vapour-dominated), and heat transfer mechanisms (convective or conductive). Enhanced geothermal systems (EGSs) are highlighted as an innovative approach to broadening the applicability of geothermal energy, enabling exploitation in areas with insufficient natural geothermal conditions.
The chapter also examines geothermal power plants, including dry steam, flash steam, and binary cycle plants. Each technology’s operational principles, efficiency, and suitability for specific geothermal conditions are discussed, with binary cycle plants recognized for their ability to utilize moderate-temperature resources. Environmental considerations, such as induced seismicity, fluid reinjection, and emissions, are addressed alongside mitigation strategies.
Through these discussions, the chapter underscores the critical role of geothermal energy in the global transition to sustainable energy systems, offering insights into its current applications, advancements, and future potential.
