Friday 3 July 2020

Geothermal power plants and 5 advantages of geothermal energy

    

    On 4 July 1904, prinle piero ginori lonti tested the first geothermal power generator in larderello italy. It successfully glows 4 bulbs. later, In 1911 the world"s first commercial geothermal power plant was built.

Image by WikiImages from Pixabay

What is the geothermal energy ?

    The geothermal energy is the energy produced by the earth itself in form of heat at the center of the earth. The fact is that the earth outer core is very hot like the surface temperature of the sun having the temperature of around 5000*c.

    

Geothermal energy conversion

    You may ask a question how the geothermal energy is converted in to electrical energy. There are some places in the earth having the hotspots of geothermal energy. The naturally occurring hydrothermal reservoir above the surface of earth produces hot water and steam. 

    The hot water and steam in the natural hydrothermal reservoir are harvest to the purpose of generating electricity by the turbine through the condenser. 

    The geothermal energy is converted into mechanical energy by the shaft turbines and then the mechanical energy is converted into electrical energy by the electric generator.

Geothermal energy and the ring of fire
Gringer, distributed under a Public domain.

    The volcanically active and earthquake prone region in the Pacific ocean is known as ring of fire. Because it contains many high temperature geothermal systems associated with active volcano.

Operation of geothermal power plant
image credit: 
Rxn111130, distributed under a CC BY-SA 4.0 licenses.

    Basically there are three different of operation of geothermal power plant.
  • Dry steam power plant
  • Flash steam power plant
  • Binary cycle power plant
Dry steam geothermal power plant

    This is one of the straight methods of power generation where the hydro thermal reservoir emits steam. Normally the water is injected into the subsurface of ground to produce the steam.

    

Flash steam geothermal power plant

    In this method, the water in injected in to the sub surface or ground to heat the water. Normally, the flash hydro thermal systems of about 200*c or more. It can capable of producing steam at pressure sufficient to drive the turbine.

     These systems are in porus and permeable rock saturated with water. The hot water from the pipe is separated as steam and water. The steam flash the turbine to produce electricity.

Binary cycle geothermal power plant 

    The main advantage of this method is to produce electricity although the temperature is moderated in subsurface. The geothermal water is used to boil a low boiling point fluid is called as working fluid. Whose vapor is them drives a generator turbine. The water is injected back in to the sub surface to extend this cyclic process of hydrothermal reservoir.

Advantages of geothermal energy
  • Geothermal energy is renewable energy because once water or steam is used, it can be pumped back into the ground.
  • It is also clean energy.
  • Geothermal power plants, unlike plants that fossil fuels, do not produce green house gases that can be harmful to the atmosphere.
  • Geothermal energy is easy on the local environment because the power plants do not require the clearing of large areas of land, damming of rivers or mining like other energy sources.
  • It is inexpensive to use. Once a geothermal system is installed, the source of energy is free to use and because the plants use very few moving parts, there are generally low maintenance costs involved.
Conclusion

    One of the cleanest renewable energy sources available under ground. But we should aware of earthquake because of artificial drilling.

Comment

     Why geothermal energy is known for clean energy?   
    

Friday 26 June 2020

Solar Energy, How it works and 5 advantages of solar energy


Do you know? The sun is almost three quarters hydrogen and most of the remaining mass in helium. Because of fusion reaction in the sun, it emits billions of degree celcius.

Image by andreas160578 from Pixabay

Energy conversion


    The sun is the ultimate source energy for all organisms living in the world. The harnessing of solar energy from the sun made by solar panels. How solar energy is transformed into another form of energy!
that is interesting story.
    The most abundant energy of sun is harnessed bu using the most abundant material silicon. The starting process of solar panels are made with silicon. The light is the smallest quantity of energy that can be transported and it because like a wave. Energy of the sun is converted to electrical energy.
image credit: Tssenthi,distributed under a CC BY-SA 4.0 licenses.

Concept of P type and N type semiconductor


    We know that silicon has 14 protons and 4 valance electrons in the outer most shell. In the czochralski, method pure poly crystalline structure silicon is made.

type

    Trivalent impurities like Al,B,Ga has 3 valance electrons in the outermost orbit. Doping of these  impurities in intrinsic semiconductor called P type material.These semiconductors have a place to hold the electrons. Because of one unpaired electron in the structure of poly crystalline.

N type

    Pentavalent impurities like Ar,Sn having 5 valence electrons in the outermost orbit. Doping these impurities in intrinsic semiconductor called N type material. These semiconductors have an extra electron in the structure of poly crystalline.

Formation of PN Junction


    The majority carrier of P type material having holes and N type material having electrons. The minority carrier of P type materials are electrons as well as n type materials are holes. The simple construction of P and N type material joined together.

    The region where P and N type material meets called the PN Junction.

Depletion region in PN Junction

    In the PN Junction, the majority carriers of N type material are migrating from N type to P type material.Hence the result in formation of positive ions in the N type and negative ions in P type region called depletion region.  Hence depletion region in the PN junction forms the electric field.

Photons strike in PN Junction


    The light is a smallest quantity of energy that can be transported and it is a part of the spectrum.
A photon is an elementary particle with an imaginary size behave like a wave.

    When light strike the PN junction and the photon energy is sufficient to generate electron hole pairs in the depletion region.

Generate electricity


    The electric field in the depletion region force the electrons and holes in the opposite direction of  depletion region. This result accumulation of electron in the n region and holes in the region.

     

Specifications


    The technical specifications of solar cells are considered as, Maximum power (W), Tolerance(%),Voc, Isc, Maximum power voltage (v), maximum power current(I), Module efficiency solar cell efficiency, Fuse rating, Water resistant, Max system voltage operating temperature,dimension and weight.

Advantages of solar energy

Image by DavidRockDesign from Pixabay

  • Eco friendly and sustainable energy. 
  • pollution free source of energy.
  • Power storing capacity because of direct current generation.
  • Transformation of energy in various ways that can be removing fossil fuel.
  • No maintenance because of no wear and tear of mechanical parts  

 Conclusion

    We should use Non conventional sources for sustainable environment for the future mankind and living organisms.

Comments

    why the efficiency of solar cell is low? how can we improve? 

Saturday 20 June 2020

The diagram below shows how electricity is generated in hydroelectric power station

   


 National geographic says,  In,1882 the world's first hydro electric power plant began operating in the united state along the fox river, Appleton.

Image by Franz W. from Pixabay

Energy conversion

    The world hydro refers too water. We all know that the static huge amount of water can have ultimate potential energy. We need to convert the potential energy into electrical energy. First of all, the potential energy in converted into kinetic energy by allow the water into the penstock. 

    The kinetic energy is then converted into mechanical energy because of water strike the turbine results in rotating the turbine. The rotating shaft is connected with alternator or generator which produce the electrical energy and then transformer is used to step down the voltage. 

    The rotation of generator defines the frequency in electrical hertz. The supply is connected to power grid of the transmission line.

Construction

image credit: Tennessee Valley Authority,distributed under a CC BY-SA 3.0 license.


    This  site is chosen by parameters which are mostly forest area having high rainfall regions. The area which is used to construct the hydroelectric power station should be easy to visit.
    The dam is built across the river to store the huge amount of water.

Water reservoir

Image by Thomas Ehrhardt from Pixabay


    Basic requirement of hydroelectric power plant is the availability of water. If the water availability is high, proportionally water reservoir is high. We can store the large amount of water depends on the height of the dam.The level of water surface in the dam is said to be head race level.

Penstock


    The dam and the rotating turbine are connected by means of penstock. The penstock is nothing but 
pipe made up of concrete or steel. Which carry water from the dam to the rotating turbine.

Regulation valve


    The value which is used to control the flow of water from the dam.

Prime mover

    image credit:U.S. Army crops of Engineers, distributed under a Public domain
   

    Water through the penstock enter into the turbine through the regulation valve. The most commonly used turbine is Pelton turbine. The potential energy of the water is converted in to kinetic energy  through penstock and then kinetic energy is converted in to mechanical energy by Pelton turbine which is rotates the shaft used to run the generator

Draft tube

    The  output of the turbine is connected to tube which release water is called draft tube. The main function of the draft tube is releasing water with partially zero energy in the river. hence, the velocity of the water is reduced.

Tail race level

    The level of water at which the water from the draft tube is tail race. The tail race level may be called  as water level of river

 Safety measures
  • Spill way
  • Surge tank

Spill way

Image by Daina Krumins from Pixabay


    The storage of water reservoir is limited to certain value. if the water raises above the certain value, it would leads to unstability of the dam causes massive flood damages all the residents and collapse the Environment. Which may endanger to flora and fauna. The water increases after the certain level must be discharged slowly via  spillway

Surge tank

    The sudden increases in pressure in penstock leads to damage of pipe lines. The surge tank is a tank which allows the water when it is in high pressure to reduce the pressure in the penstock.

Conclusion

     The water is a renewable source of energy and always exists in nature. On the other hand, the fuel needed for the thermal, diesel plants are exhaustible.

Comments below


What is the disadvantage of hydroelectric plant? why?

Thursday 18 June 2020

Introduction to Renewable Energy and Classifications of Renewable Energy



Renewable energy can be generated continuously in our nature and it is in exhaustible they are also called as non conventional source of energy and can be used in an infinite manner. for example,In our solar system the sun is mass energy source to the world and this energy helps to humans and plant to evolve. 
 Image by seagul from Pixabay

Classifications of renewable energy  


  • Solar energy
  • Wind energy
  • Hydro energy
  • Tidal energy
  • Geothermal energy
  • Biomass energy 
  • Bio fuel energy

Solar energy

Image by andreas160578 from Pixabay
 
    Sun is the huge source of energy for all living organisms what happens inside the star, the nuclear fusion reactions are take place releases enormous quantity of energy form of heat and light.

    The techniques used for harnessing the solar energy, passive heat collectors, solar cells ,solar water heater solar furnace solar power plant.

Wind energy

Image by Free-Photos from Pixabay


    Wind having a lot of kinetic energy when it is in high speed.This energy is harnessed by use of wind mills.The blades of wind will be rotating converts mechanical energy into electrical energy. Electrical energy is feed into the power grid.

Hydro energy

Image by Franz W. from Pixabay


    The dam is constructed to store the water which has very huge potential energy. the water is allowed to hit the turbine blades generator starts rotating and produce the electrical energy. But the initial construction cost of dam is very high.

Tidal energy 


   The gravitational forces of sun and moon produces tides in oceans. rise in the tidal are called as huge tidal and fall in the tidal are called as low tidal in the oceans. the tidal energy is harnessed by constructing a barrage.the sea water flows into reservoir and rotates the turbine.
    
    Which produces the electricity by rotating the generator. the water stored in the barrage reservoir flows out and again rotating the turbine. 

Geothermal energy


Image by WikiImages from Pixabay


    There is a possible of high temperature and high pressure steam field exist under the surface of earth in some places the energy is harnessed from the rocks present inside the earth.The steam of hot water comes out of ground naturally through the earth's surface form of natural geysers.

    

Biomass energy

Image by PublicDomainPictures from Pixabay


    The Organic matter produced by living  organisms plants and animals like, sewage, agriculture wastes,crop residues etc. The plants absorbs solar energy through photosynthesis are converted into biomass energy. crops like sugarcane,carbohydrate which are rich plants of energy plantations. This plants is converted into burnable gases.

    The rich hydrocarbons can yield an oil like substance under high temperature and pressure.

    The crop residues, peanut shells are common agriculture waste which produces energy by burning.

Bio fuel


   

    Methanol burns at lower temperature than gasoline or diesel. these fuels burns clean and non polluting in nature.

Conclusion

    Thus,we realize the Non conventional source is Non polluting and Environment friendly sources.But,
the initial construction cost of these power plants very high.

Comments Below


Which power plant is used world wide? Why?