Overview
This lecture discusses the Mayon Volcano, geothermal energy, its advantages and disadvantages, how geothermal power plants operate, and how volcanic activity is monitored in the Philippines.
Mayon Volcano & Geothermal Energy Basics
- Mayon Volcano is located in Albay, Luzon, Philippines, and is famous for its perfect cone shape.
- Fertile soil from volcanic ash supports agriculture in surrounding areas.
- Geothermal energy is heat from within the Earth, originated from melted magma and radioactive decay.
- Areas near active volcanoes, like Mayon, have high geothermal potential.
- The Philippines ranks second globally in geothermal energy production due to its location in the Pacific Ring of Fire.
Geothermal Power Plant Operation
- Wells are drilled into the earth to access steam or hot water from geothermal reservoirs.
- Pressure drop at the surface turns hot water into steam.
- Steam spins a turbine, converting thermal energy into mechanical energy.
- The turbine’s mechanical energy generates electricity via a generator.
- Steam is cooled, condensed back to water, and pumped underground to restart the process.
Advantages and Disadvantages of Geothermal Energy
- Advantages:
- Renewable and naturally replenished energy source.
- Low carbon footprint and minimal pollution.
- No need for external fuel.
- Disadvantages:
- High maintenance and operational costs.
- Possible release of underground gases and minor environmental pollution.
- Risks from volcanic eruptions and minor induced earthquakes.
Monitoring Volcanic Activity
- Volcanologists observe warning signs like increased earthquake frequency, chemical changes in hot springs, widening ground cracks, plant withering, temperature rise in hot springs, and color change in steam.
Key Terms & Definitions
- Geothermal Energy — Heat energy stored inside the Earth from magma and radioactive decay.
- Geothermal Reservoir — An underground pool of hot water beneath the Earth's surface.
- Turbine — Machine that converts steam’s energy to mechanical energy.
- Generator — Device that turns mechanical energy into electricity.
- Pacific Ring of Fire — Region around the Pacific Ocean with high volcanic and seismic activity.
Action Items / Next Steps
- Prepare to study how different factors affect local climate in the next lesson.