Overview
This webinar focuses on geothermal energy in Indonesia, discussing its potential, benefits, challenges, environmental impacts, and the technical and social considerations for its development and use.
Introduction to Geothermal Energy
- Geothermal energy uses the earth’s internal heat, primarily from radioactive decay and residual heat.
- Indonesia is one of the world’s richest countries in geothermal reserves, especially in volcanic regions.
- Geothermal energy is renewable, reliable, and produces low greenhouse gas emissions.
Geothermal Resource and Potential in Indonesia
- Indonesia has abundant geothermal potential, mainly located on the "Ring of Fire" due to frequent volcanic and tectonic activity.
- Only a small portion of the available geothermal potential is currently utilized.
- Major obstacles include high initial costs, complex permits, infrastructure needs, environmental concerns, and limited investor interest.
How Geothermal Energy Works
- Heat from magma warms underground rocks, which in turn heats water to create steam.
- Steam is extracted via deep wells (1,000–3,000 m) and used to drive turbines that generate electricity.
- Used water is reinjected underground to sustain the reservoir and minimize environmental impact.
Environmental and Social Aspects
- Geothermal plants emit very low levels of CO2 and pollutants compared to coal and fossil fuels.
- Responsible management requires reinjecting water and monitoring for toxic gases like H2S.
- Social conflict can arise from misinformation and local resistance; community engagement and education are crucial.
Technical and Exploration Process
- Exploration involves geological, geophysical, and geochemical surveys to locate viable sites.
- Drilling is costly but necessary for confirming resource viability.
- Wells are drilled with multiple protective casings and cement barriers to prevent groundwater contamination.
Broader Applications and Global Examples
- Beyond electricity, geothermal can be used for industrial heating, drying crops, greenhouses, and direct-use applications.
- Countries like New Zealand, Iceland, and Japan utilize geothermal for diverse needs and have advanced technologies for deeper and lower-temperature resources.
Challenges and Future Directions
- Geothermal development is limited by costs, technology, regulatory barriers, and location (often in protected forests).
- Advances in research and drilling technology, improved permitting, and multi-sector cooperation are essential for growth.
- Students are encouraged to pursue related studies (geology, engineering, etc.) for future innovation.
Key Terms & Definitions
- Geothermal energy — heat energy from the earth used for power and heating.
- Mantle — the layer of earth beneath the crust, containing high temperatures.
- Reservoir — underground area of hot water/steam from which geothermal energy is extracted.
- Well casing — protective lining in wells to prevent leaks and contamination.
- Heat exchanger — device for transferring heat from geothermal fluids to other systems.
- Reinjection — process of returning used water back underground.
Action Items / Next Steps
- Review earth structure (core, mantle, crust) and heat transfer mechanisms (conduction, convection, advection).
- Study Indonesia’s geothermal map and learn about geothermal formations (volcano-associated, plutonic, sedimentary).
- Research recent developments in geothermal projects and their environmental regulations.
- For students: explore STEM subjects relevant to geothermal exploration and energy.