G141 REVIEW:  GEOTHERMAL ENERGY

Geothermal Reservoir Types

1. Hydrothermal
1. Steam
2. Hot water
2. Dry rock (experimental, not yet in commercial use)
3. Magma (far in future)

Requirements for Geothermal Energy

• High Geothermal gradient (near magma body)
• Fractured/porous rock
• Groundwater

Advantages of Geothermal Energy

• Alternative to fossil fuels
• Little pollution, no contribution to greenhouse effect
• Nearly renewable energy source

Fractional Crystallization

• Loss of heat (non-renewable)
• Pollution due to release of volcanic gas
• Mineralization in pipes