M4_U1_EXPLAIN_Energy_Resources_(geothermal) (1)

Geothermal Energy Overview

Definition

  • Geothermal Energy: Energy derived from the internal heat of the Earth's crust.

    • Origin: From Greek words: "ge" (earth) and "thermos" (heat).

Objectives of the Lesson

  • Understand how heat from the Earth is utilized for energy.

  • Differentiate between geothermal heat pumps and geothermal power plants.

  • Identify and locate geothermal power plants in the Philippines.

Geothermal Heat Sources

Heat Origins

  • Approximately ½ of geothermal heat is residual from the Earth's formation (4.5 billion years ago).

  • The other ½ comes from natural radioactivity.

  • Note: Geothermal resources are not inexhaustible.

Geothermal Gradient

  • Definition: The average rate at which temperature rises with depth within the Earth.

  • At greater depths, underground rocks and water experience increased temperatures.

Types of Geothermal Energy

Classification by Temperature

  1. Low-Temperature Geothermal Energy

    • Range: 20°C to 90°C

    • Uses: Heating for homes, offices, and public facilities.

  2. Medium-Temperature Geothermal Energy

    • Range: 90°C to 160°C

  3. High-Temperature Geothermal Energy

    • Temperature: Above 160°C

    • Both medium and high-temperature sources harness extremely hot water and steam to generate electricity.

Historical Context

  • The first geothermal power plant was established in 1904 in Larderello, Italy by Prince Piero Ginori Conti.

Geothermal Resource Availability

  • Heat flow varies by region.

  • Geothermal Heat Flow: Energy availability per surface area over time (average: 0.06 watts/m²/year).

  • Geothermal reservoirs: Collections of hot water typically found in sedimentary basins.

    • High-temperature geothermal energy is often near volcanoes (heat flow can reach 1 watt/m²).

Harnessing Geothermal Power

Mechanisms

  • Geothermal reservoirs consist of water heated by magma under the Earth's surface.

  • Water or steam may escape as geysers or through cracks.

  • Harnessing steam drives geothermal power plants.

Utilization Methods

  1. Direct Utilization: Using thermal energy for heating.

  2. Conversion to Mechanical or Electrical Energy: Achieved through:

    • Geothermal Heat Pumps

    • Geothermal Power Plants

Geothermal Heat Pumps

Types of Systems

  • Closed Loop Systems: Can be set up as vertical, horizontal, or in ponds/lakes.

Geothermal Power Plants

  • Facilities tapping into geothermal energy to produce electricity.

Geothermal Power Plants in the Philippines

  1. Palinpinon, Negros Oriental

  2. Makiling-Banahaw (Mak-Ban), Laguna

  3. Bacon-Manito, Sorsogon City

Additional Geothermal Power Plants

  • Leyte Geothermal Production Field, Leyte

  • Mindanao Geothermal Production Field, Kidapawan City, North Cotabato

  • Northern Negros Geothermal Production Field, Bago City, Northern Negros

  • Tiwi Geothermal Power Plant, Albay, Bicol

  • Malitbog Geothermal Power Station, Kananga, Leyte

Global Geothermal Energy Landscape

Top 10 Countries by Installed Capacity (in MW)

  1. United States: 3,442 MW

  2. Philippines: 1,968 MW

  3. Indonesia: 1,339 MW

  4. Mexico: 1,005 MW

  5. New Zealand: 967 MW

  6. Italy: 941 MW

  7. Iceland: 665 MW

  8. Kenya: 607 MW

  9. Japan: 502 MW

  10. Turkey: 410 MW

  • Other countries: 1,142 MW (Data Source: ThinkGeoEnergy Research, GEA, IGA, 2015)