Enhanced geothermal systems

Definition

Enhanced geothermal systems (EGS) are engineered reservoirs created to extract geothermal energy from hot, dry rock formations that lack sufficient natural permeability and fluid content. By injecting water into these formations to create fractures, EGS allows for the circulation of fluid that can be heated by the Earth's natural heat and then extracted for energy production. This method significantly expands the potential for geothermal energy exploitation in regions that were previously deemed unsuitable.

5 Must Know Facts For Your Next Test

1. EGS can significantly increase the geographical range where geothermal energy can be harvested, including areas not traditionally associated with geothermal resources.
2. The process involves drilling deep into the Earth's crust, where temperatures are high enough to generate steam or hot water that can be used for energy production.
3. EGS has the potential to provide a stable and reliable source of renewable energy, which can help reduce reliance on fossil fuels.
4. Environmental concerns regarding EGS include potential induced seismicity (earthquakes) and groundwater contamination, necessitating careful site assessment and monitoring.
5. Current research and development efforts are focused on improving the efficiency and sustainability of EGS technology to maximize its contribution to the energy mix.

Review Questions

• How does the process of creating an enhanced geothermal system impact the surrounding geology and environment?
  • Creating an enhanced geothermal system involves injecting water into hot, dry rock formations to fracture them and allow for fluid circulation. This process alters the geological structure and can lead to changes in local pressure and temperature. While it expands geothermal energy access, it also raises concerns about induced seismicity, as the fracturing can trigger small earthquakes. Environmental impact assessments are essential to mitigate these risks while harnessing geothermal energy.
• Evaluate the advantages and disadvantages of enhanced geothermal systems compared to conventional geothermal energy extraction methods.
  • Enhanced geothermal systems offer several advantages over conventional methods, including access to previously untapped geothermal resources in less geologically active areas. EGS can also provide a more consistent energy output compared to some traditional sources. However, disadvantages include higher initial costs due to complex engineering requirements and environmental concerns related to induced seismicity and water use. Balancing these factors is critical for advancing EGS technology.
• Assess how advancements in enhanced geothermal systems could influence global energy strategies and sustainability efforts in the coming decades.
  • Advancements in enhanced geothermal systems could play a significant role in transforming global energy strategies by providing a reliable and renewable source of power. As countries seek to reduce greenhouse gas emissions and transition away from fossil fuels, EGS could complement other renewable sources like solar and wind by offering baseload power generation. Furthermore, improved technologies may enhance the sustainability of EGS by minimizing environmental impacts, making it a key component of future energy solutions that support climate goals and promote energy independence.

Related terms

Geothermal gradient: The rate at which temperature increases with depth in the Earth's crust, which is crucial for determining the viability of geothermal energy resources.

Hydraulic fracturing: A technique used to create fractures in underground rock formations by injecting high-pressure fluid, commonly employed in EGS to enhance reservoir performance.

Hot dry rock: A type of geothermal resource characterized by high temperatures and low permeability, which is targeted in enhanced geothermal systems to generate electricity.