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Hydropower

Geothermal Energy: Earth's Internal Heat

Discover how we can harness the tremendous thermal energy stored within our planet and explore the science of geothermal power

What is Geothermal Energy?

Geothermal energy is the thermal energy stored within the Earth, continuously generated by radioactive decay of minerals and residual heat from the planet's formation billions of years ago. This heat flows from the Earth's hot interior to its cooler surface, creating geothermal gradients that can be harnessed for power generation.

Unlike solar and wind energy, geothermal provides consistent baseload power regardless of weather or time of day. The Earth's heat is essentially limitless on human timescales, making geothermal one of the most reliable renewable energy sources available.

Why Geothermal Matters for Climate

Geothermal energy offers carbon-free electricity with minimal land use compared to other renewables. It provides stable power that can complement intermittent sources like solar and wind, making it essential for achieving net-zero emissions.

Interactive Earth Heat Explorer

Earth's Internal Structure

15°C at 1000km depth
Crust
Mantle
Outer Core
Inner Core

Geothermal Parameters

Geothermal Gradient

0°C/km
Temperature increase per kilometer of depth

Types of Geothermal Systems

Hydrothermal

Hot water and steam reservoirs

Temperature: 150-350°C
Locations: Volcanic areas worldwide
Hot Dry Rock

Hot rock without natural water

Temperature: 200-600°C
Locations: Deep underground anywhere
Geopressured

High-pressure hot water zones

Temperature: 100-200°C
Locations: Sedimentary basins

Key Insight: Geothermal energy taps into Earth's internal heat, which is continuously produced by radioactive decay and residual heat from planet formation. The temperature increases with depth following the geothermal gradient.