Geothermal energy is generated by tapping into the thermal energy or heat at the Earth’s core. This energy is harvested by drilling deep into the ground, then pumping in a heat transfer fluid such as water or steam.
The energy that is transferred up to the surface is converted into usable power. Water-based systems are the most effective, but also have the potential to cause contamination in the nearby water table. This means that great care must be taken to not damage the local water supply.