Geothermal Plant (Civ6)/Civilopedia

Just beneath the surface of the earth lies a form of sustainable, cost-effective thermal energy. Always available, the heat rising from the core of the planet has been enjoyed by people for thousands of years, often in the form of relaxing hot springs. But harnessing the energy of the earth to use as power is a relatively new practice. The world's first geothermal plant was built in Italy in 1911, and the second in 1958. Today, 24 countries are generating power through geothermal plants.
These plants are often found near tectonic boundaries, reducing the depth of drilling required to reach significant resources, but come with the risks of volcanic activity. Additionally, the plants create a side product – fluids containing gasses or toxic chemicals. While modern plants return most of these fluids to the earth to reduce environmental impact, some escape as steam, wafting through the air as the pungent sulfuric scent of rotten eggs.