Geothermal Power Plant
Geothermal power comes from the slow decay of radioactive minerals such as uranium, which causes the rocks to become magma. Tectonic plate movement causes the movement of magma up from the edges, forming a reservoir in which geothermal steam and hot water can be recovered through wells.
Geothermal energy uses heat to produce steam, which in turn powers a generator to produce electricity.
Geothermal energy is generated deep in the ground, in the form of hot molten rock, or a Magma formed from the collapse of radioactive materials like uranium.
This energy becomes available to us at the borders of tectonic plates, when rubbing together and sliding under the another, causing the magma to break from the edges and pushed to the Earth’s surface forming a geothermal reservoir.
Types of Geothermal Power Plants
There are three types of geothermal steam plants depending on the way the energy is generated:
1. Dry Steam Power Plant : The first is the dry steam power plant which is used to generate power directly from the steam generated inside the earth.
In this case, we do not need additional heating boilers and boiler fuel, as steam or water vapour fill the wells through rock catcher and directly rotates the turbine, which activates a generator to produce electricity.
This type of power plant is not common since natural hydrothermal reservoirs dry steam are very rare.
2. Flash Steam Power Plant : The most common type of geothermal power plant, flash steam plants use waters at temperatures greater than 360F.
As this hot water flows up through wells in the ground, it is collected in a flash tank where drop in pressure causes the liquid to boil into steam.
The steam is separated from the liquid which is then used to run turbines which in turn generate power. The condensed steam is returned to the reservoir.
3. Binary Steam Power Plant : This type of plant uses high temperature geothermal water to heat another fluid which has a lower boiling point than water.
This fluid vaporizes to steam, drives the turbines, then condenses to liquid to begin the cycle again.
The water, which never comes into direct contact with the working fluid, is then injected back into the ground to be reheated. Since the most resources are with lower temperature the binary steam power plants are more common.