Thermal energy created as well as stored inside the Earth's crust is generally referred to as geothermal energy. This same Earth's core maintains the same temperatures as that of the Sun, which is almost continuous attributable to the continuous mechanism of nuclear fusion.
Because of the tremendous warmth as well as pressure, certain rocks melt, causing the mantle gradually rise. It should be the energy produced by the warmth well within Earth.
Hot rocks throughout the Earth's core send water vapor as well as pressure onto the Planet's surface. Such steam powers turbines but also generates energy.
Therefore, geothermal energy is a source of renewable energy derived from the core of the planet.