The way in which geothermal energy is used depending on the composition of the underground geothermal reservoir, e.g. whether it contains groundwater or what temperature it has. There are five basic types of geothermal systems:

Hot water binary cycle (Hot water from underground with a temperature not exceeding 100 °C is pumped to the surface and used mainly for heating.)

Mixture of water and steam (Also known as dry steam and flash steam. The water in the underground reservoir is of high temperature and pressure. As it’s pumped to the surface, its pressure drops, turning it partly into steam, which powers the plant’s turbine.)

Pressurized water (Saline water from depths of 3—5km, which is under extreme pressure.)

Hot dry rock (Water is injected into the rock containing no groundwater and pumped to the surface when it is heated. Sometimes it is necessary to prepare the reservoir with small underground blasts to increase the number of fractures through which the water can circulate.)

Magma (Molten lava has a high temperature and therefore contains a large amount of energy, but its use is complicated because it is a highly aggressive environment.)