Geothermal energy is the thermal energy that is obtained under the earth’s surface. Geothermal energy is the renewable energy source in the world. People are generating electrical energy by using geothermal energy. Now we will share modern geothermal power plant details. Basically, coal, oil, gas, and other non-renewable energy sources are reducing day by day. For this reason, people are looking for renewable energy sources. Geothermal energy can be found thousands of meters deeper from the earth’s surface.
We know that the temperature under the ground is much higher. The water there is very boiling, and electricity is generated by using that boiling water vapor. The water vapor or water steam energy is used to produce mechanical energy by the turbine. The turbines are connected to the alternator. An alternator converts mechanical energy into electrical energy, and such kind of power plant is called a geothermal power plant. A geothermal plant can be used to generate electricity to meet our load demand.
How Does A Modern Geothermal Power Plant Work?
Whenever we hear about geothermal energy then it seems to be that it is the earth’s natural energy. We know that there are volcanoes under the ground and how long deeper you go from the earth’s surface you will get a higher temperature, so the water under the ground is much hotter.
If we make any power plant intended to generate electricity, then it will be considered as a geothermal plant. Whenever hot water is pumped from the thousands-meter-deep place of the earth’s surface. Whenever hot water reaches the earth’s surface then the water pressure is dropped.
In this case, the water is turned into steam. This steam hits the steam turbine with high pressure and the steam turbine converts steam energy into mechanical energy. At the same time, the alternator is coupled with the steam turbine.
Whenever the turbine rotates the alternator also rotates at the same speed as the turbine. As a result, the alternator receives mechanical energy from the steam turbine and converts it into electrical energy. Geothermal energy is a renewable energy source like solar energy, wind energy, and other rechargeable energy sources.
What are the Types of Geothermal Power Plants?
Geothermal energy was used in Italy in 1904, and after that many countries made geothermal power stations to generate electricity. A geothermal power station is a type of power plant that uses the earth’s heat source to generate electricity. The location of a geo power plant is near tectonic plate areas where a large number of volcanos are available.
One of the most active geothermal regions in the world is called the Ring of Fire, which surrounds the Pacific Ocean. There are four types of geothermal energy resources, such as hot dry rock, hydrothermal, magma, and geo-pressure. On the other hand, there are three types of geothermal power plants, such as
- Dry steam
- Flash steam
Dry Steam Power Plant
A dry steam power plant is one kind of geothermal plant. Steel pipe is placed underground from the earth’s surface. The steel pipe is used to carry steam from the hot water and send the steam to the turbine at high pressure.
In this case, the turbine rotates and the alternator also rotates with the steam turbine, and then electrical energy is produced. It is noted that a pipe is the main way to collect steam from the hot water into the underground. Thermal power plants need steam to rotate the steam turbine. For this reason, more steam is emitted through the chimney.
Binary Cycle Power Plants
Primarily, heat from geothermal liquids evaporates secondary fluids, which then drive turbines and subsequently drive generators. In closed-loop systems in binary cycle power plants, nothing is released into the atmosphere except water vapor. A binary cycle power plant is one where geothermal resources are not hot enough to produce steam, or where the source contains mineral or chemical impurities to allow flashing.
In the binary cycle process, geothermal fluid passes through a heat exchanger. The secondary liquid with a low boiling point from water (isobutene pentane or ammonia) evaporates towards the low temperature of the heat exchanger and expands through the turbine to generate electricity.
A binary cycle power plant is made for lower-temperature reservoirs as compared to the flash steam and dry steam power plant, and both power plants are employed 1800 to 3600 but binary cycle power plants can be employed 1070 to 1800
Flash Steam Geothermal Power Station
Indeed, Flash type electricity production plants are one of the most common types of geothermal power generation plants in the world. Flash steam geothermal power plants take high-pressure hot water from the depths of the earth and convert it into steam to run the turbine and the turbine rotates the generator again.
In this case, for flash steam geothermal power generation, liquids at a temperature of 360 ° F (182 ° C) or higher are pumped into a tank at high pressure which is contained in a tank at a much lower pressure, causing some liquids to evaporate faster. When the steam cools, it condenses in water and is injected into the ground for reuse. Most geothermal stations are flash steam power plants.
Advantages of Geothermal Power Station
Geothermal energy is a renewable energy source like solar energy, wind energy, and other renewable energy. There are lots of advantages to a geothermal power station. For this reason, people are looking for a renewable energy source to meet their daily needs. The advantages of geothermal energy are given below.
- Geothermal energy is eco-friendly because no smoke and fumes are produced in this power plant.
- Geothermal energy is rechargeable or renewable energy.
- It is a huge potential energy source.
- Geothermal energy sources provide sustainable energy compared to the sun and wind power sources.
- It is a reliable energy source.
- Geothermal energy doesn’t require any kind of fuel (coal, oil, gas).
- Running costs are low compared to coal, gas, oil, and power plants because it does not require that.
Geothermal Heating Pump
On the other hand, the geothermal heating pump is used for the constant temperature near the surface of the earth to heat individual or multiple buildings. Basically, this system can be used in cold countries. The heating pump transfers heat from groundwater into the building, this process is used in the winter season.
It is noted that the largest geothermal power station can produce bulk electrical energy. If we consider the USA, statistics show that the USA generates approximately 23,000 MWh daily basis. It is a CFC (chlorofluorocarbon) free gas and the running cost is low, and it is a renewable energy source. For this reason, it is becoming more popular. But every single country doesn’t use this geothermal energy due to some limitations. It means specific location and deep research.
Where is Geothermal Energy Used?
The geothermal plant is suitable for generating a small amount of electricity. Geothermal electricity production plants work like nuclear power plants or coal power plants. Geothermal energy is a renewable energy source in the world. It can be used for three main purposes, such as
- For direct heating.
- To generate electricity.
- Geothermal heating pump.
- homes, fisheries, and industrial processes.
For Direct Heating
Without that, there are some examples of geothermal energy. Direct using means that those are cold countries like most European Union (EU) countries, USA, Italy, and other countries use the direct heating system to get rid of cold weather. They use hot water from a spring or reservoir that is located near the surface of the earth. This water can be used for bathing, cooking, heating, and other purposes. A direct heating system is also used to heat individual or multiple building purposes.
Final Thought
Geothermal energy is used to generate electricity for personal and commercial use. The geothermal power plant is a thermal power plant. The alternator is coupled to the steam turbine and the alternator converts mechanical energy into electrical energy.