Geothermal power plants harness heat from the Earth’s interior. What is the primary and continuous natural process that generates the deep heat used for commercial geothermal energy extraction?

💡 Explanation:

The Earth's internal heat, which powers geothermal energy, originates primarily from two sources: heat left over from the planet's formation, and heat continuously generated through the radioactive decay of naturally occurring isotopes within the mantle and crust.