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Saturday, July 27, 2013

A List of 10 Most Significant Environmental Threats That We are Going to Face

Early We had discussed 8 most dangerous human activities that harm the environment.  This article is a continuation of that entry. You may have noticed we have missed several other human activities from that list. We are glad to see your suggestions and opinions in the commenting area. Here in this article we are going to discuss about "10 Threats that we are going to face in 21st century."

1. Global Warming

Global Warming in Guana

As a result of over Deforestation and emission of excess amount of oxides of carbon from power plants and vehicles there has been formed a green house effect around the Earth. Global warming would leads to water scarcity and extinction of several living organisms.

2. Water Scarcity

oh dear.. save water!

Causes: Destruction of water resources, Global warming, Deforestation, Decrease in rain water

Affects: Extinction, diseases,

3. Energy Scarcity

Causes: Great dependence on traditional energy sources, slow growth for renewable energy technology, over use of energy sources (exploitation)

Affects: Slower developments, loss of economic stability of countries, International war for energy.

4. Food Scarcity and Food Poisoning

Causes: population explosion, conversion of green farm areas to concrete farms, diet style

Affects: Extinction, war

5. Climate Change

Causes: global warning, over exploitation of minerals and resources, pollution of water bodies.

Affects: Mental retardation, diseases, extinction of Living organisms

6. Flood

Causes: Deforestation,reduction in water absorption capacity of soil,

Affects: affects farms, habitat loss,difficulty in transportation

7. Decrease in Under Water Level

Causes: Over exploitation of under water reservoirs, deforestation, use of plastic covers

Affects: Water scarcity

8. Sea level Rise and Decrease in Land Area

Causes: Ice melting at Poles due to Global warning.

Affects: Sea level rise, total land area reduction,

9. Earth quake

Causes: Dams, uncontrolled stone mining, nuclear experiments.

Affects: loss of habitat, death of human being as well as living organisms.

10. Infectious Diseases and Carcinogens and mutation

Causes: Radiation, ozone layer depletion, nuclear reactor explosions, mobile towers

Affects:  mutation, death of living organisms

How to Reduce the Strength of These Environmental Threats?

The one and only method to reduce the strength of environmental threats is afforestation.

  • Afforestation
  • Reduce the emission of oxides of carbon
  • Population control
  • Utilize renewable energy sources
  • Protect water resources
  • Utilize rain water
  • Avoid plastic
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8 Most Dangerous Human Activities That Harm The Environment

Balance is the most important factor when defining the word "nature". Each and every components and resources lies under a balanced condition. Any small change in those components will induce an imbalance in whole system of nature. Intolerable condition leads to natural hazards!

Here we are going to discuss about 8 most dangerous human activities that harm the precious environment. Mankind is exploiting the nature for his profit. If he is continuing his cruel exploitation of nature mankind as well as all other living organisms on earth will disappear.

Human Activities that harm the environment

  •  Deforestation
  •  Extreme level of carbon emission
  •  Over exploitation of minerals and resources
  •  Stone Mining
  •  Sand Mining
  •  Paddy field filling
  •  Hill leveling
  •  Over use of plastics

1. Deforestation

We have lost more than 90 percent of forest area since 1900. Man exploits Earth's forest cover for woods, buildings, land and other resources. Deforestation due to natural hazards and forest fires are termed as natural deforestation. Forest is one of the most significant factor in natural balance. Read more about impacts of deforestation.

2. Extreme level of carbon emission

We are largely relies on petroleum based fuels for our energy needs. Even though renewable sources of energy has been gaining more and more attention, there is no reduction in interest on petroleum based fuels. It is because of the high energy density of traditional energy sources. We know that availability of petroleum fuels are decreasing and the technology world is experimenting with renewable energy sources for sustainable energy. Burning of carbon based fuels (petroleum and coal) releases a large amount of carbon dioxide to the atmosphere. This carbon dioxide causes global warming and several  other environmental issues. Read more about global warning!

3. Over exploitation of Minerals and Resources

We should remember that, the nature and its resources are not only for human kind but also for other living organisms. Due to the selfishness we are exploiting the nature up to maximum possible. Such an over exploitation would lead to natural imbalance. Read more about effect of over exploitation of minerals and resources.

4. Stone mining

Stone is one of the main building material. There are several types of stones that can be mined from the earth. (Example: red stone, black stone) It is sure that uncontrolled stone mining would effect the balance of earth. Think a while when mining the heart of earth.

5. Sand mining

Over extraction of sand would kill rivers. Sand mining from coastal areas would reduce land area.

6. Hill leveling

Hill leveling would affect under water level destruction of habitats

7. Wet land/ Paddy field filling

Filling of fields to construct buildings and houses would leads to  future water scarcity. Fields are resources of water. We have to
maintain those precious areas.

8. Use of plastic covers

Waste plastic covers deposited on the top layer of earth would reduce the water absorption capacity of the soil. It will alter the chemistry of the soil as well as under water level. So we have to use degradable materials instead of plastics.

What are you thinking now? Did you ever think about the effect of these dangerous human activities? Comment your opinion if you love your Earth?
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Friday, June 7, 2013

How to Make Your Own Solar Panel Or Solar Cell at home?

Solar Cell
Image Credit
How to make a simple solar cell for kids? Here in this post you can learn two simple methods to make an experimental solar cell, for the purpose of impressing your kids. Or you can use this cell as a photodetector.

Solar cell manufacturing is a very expensive process, that's why even a small solar installation costs around $1500-$2000. However, you can make a simple solar cell by following some simple instructions as listed below. Keep in mind that the functioning of the device depends upon the perfection of your construction.

A solar cell is made up of a semiconductor. They are used to convert the energy from the world's largest renewable energy source, the Sun! Solar radiations carry enormous amount of energy. It is possible to harness energy from sun light by using solar cells or solar panels. There are similar devices used to harness other forms of energy from the sun. Solar heaters and parabolic concentrators are used to harness infrared radiations from the sun. A solar cell actually converts the energy of a photon to electricity. Here we are going to make a simple solar cell by using easily available materials.

Method-1 to make solar cell at home by using Cuprous Oxide

In the first method, we uses a copper plate to construct a solar cell
other than silicon based semiconductors. Materials needed,

1. Copper plate
2. Burner
3. Alligator clips
4. Copper wires
5. Bottle or jar
6. Salt water
7. Multimeter


1. Take a square sheet of copper about 5-8 inch width.

2. Wash your hands thoroughly and dry them.

3. Remove all the foreign particles from the copper sheet (example:grease)

4. Remove the top oxide layer by using sand paper or emery cloth from both sides.

5. Now you have a copper sheet with bright and shiny red sides.

6. Now we have to create a cuprous oxide layer on the copper plate.

7. Place the plate directly over the burner (highest settings)

8. Wait untill a thick black layer of "cupric oxide" to form on the top surface. It may take up to 30-50 mins.

9. After the heat treatment remove the black layer of cupric oxide from the copper plate. Usually it will flake off if you allowed the plate to cool naturally. Due to the difference in cooling rates of cupric oxide and copper it will be very easy to remove the top black layer.

9. Under the black layer of cupric oxide you will find another layer of cuprous oxide which is photosensitive.

10. Cut another piece of copper sheet and bend both pieces gently. Arrange those both pieces in a bottle or jar without touching one another. When arranging the plates be careful to place the cuprous oxide layer face outwards in the jar.

11. Attach two alligator clip leads to both the copper plates.

12. Connect the lead from cuprous oxide to negative terminal of the meter and copper plate to positive terminal.

13. Then carefully pour a little salt water into the jar by leaving an inch of plate above the salt water.

You are done! A simple solar cell is ready. The meter will read up to 50 microamps in the sunshine.

Method-2 Make a Solar cell Using Transistors

Now we are going to learn "how to make a silicon solar cell" using transistors. We know that a solar cell is a P-N junction semiconductor. It is possible to build such a solar cell using transistors.

1. Buy some transistors from electronic shop

2. Break the body of the transistor and remove the silicon plate without damaging the leads.

3. Yes! This can work as a solar cell.

4. Connect the similar leads of two or more transistors.

5. Check the output of the solar cell using a multimeter in bright sun     light.

Remember that both the solar cells cannot harness energy from the sunlight to turn on even an LED. These solar cells cannot be used to generate much more electricity. But can be used as a photo detector for school experiments.
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Tuesday, May 21, 2013

Can You Turn Energy into Matter?

According to Albert Einstein, one of the famous scientists who derived the equation for mass-energy conversion said that, it is possible to convert Matter into Energy. We know that nuclear power generation is concerned with the conversion of mass or matter into energy. A very large amount of energy can be liberated from the matter according to Einstein's Energy equation.


Where m is the mass and c is the speed of light in vacuum.

This equation is known to everyone who studied physics. But some months ago when I was checking the statistics of the traffic to my website I found a search query that made my mind unstable (Search query: The title of this article). I really appreciate that googler. Suddenly I called my Physics teacher (Mr. Jobish John) to ask about the Energy-Mass Conversion. He guide me through the correct way to understand the energy-mass conversion. (Thank you sir!)

Is it possible to convert Energy to Mass?

We know that, according to Einstein's equation (E=mc2) it is possible to convert mass into energy. But it still tells us that it takes a huge amount of energy to generate matter in this way. Particle accelerators can do this. Particle accelerators are able to convert energy to subatomic particles.

For example by colliding electrons(-e) and positrons(+e), some of the kinetic energy in the collision goes in to creating new particles. But these newly generated particles can't combine to form atoms, molecules and bigger (less microscopic) structures that we associate with matter in our daily life. This is why, when you convert energy into matter, it may contain both matter and antimatter. ie, you can only create matter-anti-matter pairs out of energy.

You may have heard that anti-matter has a tendency to combine with matter and turn itself back into energy. That's the reason behind the non-existence of individual matter or anti-matter particles in particle accelerators.

Production of matter and anti-matter pair is known as pair production. Pair production provides a conceptual framework for how our internal world gets translated into the physical reality we experience. The phenomenon of pair production can be viewed in two different ways.

One way is as a particle and antiparticle and the other is as a
particle and a hole.

The equation gives basic idea about the pair production.

γ --> (+e)+(-e)

Gama radiation is converted to electron and positron in nuclear fission reactions. They are unstable, because positron is the
anti-particle of electron.

If a particle accelerator could produce matter and anti-matter pair from energy its existence cannot continue even for a fraction of second. When the anti-matter meet the matter they will combine together and form energy.

Suggested article: Scientists discover how to turn light energy into matter after 80-year quest by Gail Wilson on 19 May 2014

Three physicists (Imperial College) worked out a relatively simple way to physically prove a theory first devised by scientists Breit and Wheeler in 1934. Breit and Wheeler suggested that it should be possible to turn light into matter by smashing together only two particles of light (photons), to create an electron and a positron – the simplest method of turning light into matter ever predicted.

In a fiction story I have read that each and every matter (including soil,wood,body,cloths etc) have its own antimatter in the world. They are separated by a mysterious force. At the end of the world weakening of this force will lead to conversion of the whole matter to energy. The end of World.
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Saturday, May 18, 2013

How Magneto Hydro Dynamic (MHD) Generator Works?

Traditional electric generators (Dynamo) are working on the principle of Faraday's laws of electromagnetic induction. A dynamo consists of a moving metal conductor in a strong magnetic field to generate electricity.

There are AC generators and DC generators. AC generators are usually known as alternators. It is possible to convert an alternator to DC dynamo by installing a Commutator (a splitted ring arrangement), which will convert the alternating current to direct current.

Here we are discussing about Magneto hydro dynamic generators. Magneto Hydro-Dynamic Conversion of energy is a direct conversion of thermal energy and kinetic energy into electrical power. A fuel cell is also a direct converter of energy. Read more about fuel cells.

A M.H.D generator works on the same principle as that of a Dynamo. In other words, process of MHD power generation is an application of Faraday's laws of electro-magnetic induction to fluid conductors. MHD generator lacks moving parts but they operate at high temperatures. MHD was developed because of the hot exhaust gas of an MHD generator can heat the boilers of steam power plant, increasing overall efficiency.

In conventional generators magnetic flux is cut by metallic conductors and e.m.f produced is proportional to rate of cutting of flux. In MHD generator, fluid conductors are used. The fluid may be gas at elevated temperatures or liquid like sodium or potassium.

Making gas a conductor of electricity is a difficult process. It is to be heated to a very high temperature to dislodge the electrons of gas atoms which are tied up with electrically neutral particles. This process is called ionization. Atoms as such are electrically neutral. When they are ionised they become electricaly charged particles and gas becomes a conductor.

Unlike the conventional electrical machine which is essentially an electromechanical converter, MHD Generator is a heat engine operating on turbine cycle transformig internal energy of gas into electrical energy.

A plasma of hot gas is passed through a duct of varying rectangular cross section. One pair of walls (top and bottom) are insulated. They form the poles of the magnet. Magnetic field is set up between them.

Motion of the plasma in the magnetic field induces an emf which is at right angles to the magnetic field as well as to the direction of gas flow. Electrical energy is extracted from the plasma through the electrode pair which are externally connected to the load.

Working Principle of MHD generator- The Lorentz Force Law

The Lorentz force law describes the affect of magnetic field on moving charges. A simple explanation for of the law is given by the following formula.


Where F is the force acting on the particle. Q is the charge of the particle, v is the velocity of the particle, and B is the magnetic field. The vector F is perpendicular to both v and B according to the Fleming's right hand rule.

About the Construction of MHD Generators

When gas flows across a magnetic field and current is induced, force tending to slow down the motion of the gas is experienced. Therefore ducts of MHD generators are made diverging to accommodate the same mass of gas at smaller velocity.

Both the insulators and electrods have to withstand as high as 3000 degree celsius of temperature. They must have good resistance to thermal shock, abrasion and chemical attack.

Energy is needed to magnetize the electromagnet used in MHD Generators. To reduce the energy loss due to magnetization
Superconductive materials are used.

The working medium after leaving the generator, still possesses considerable amount of heat which can be utilised for preheating the gas or for generation of steam.

Inorder to achieve a reasonable ionization and high electrical conductivity at high temperatures like 2000-3000 degree celsius, the gases are seeded with additives like alkali metals.

Types of MHD Generators

1. Faraday generator
2. Hall generator
3. Disc generator

A coal plant installed with MHD generator can give up to 60%
efficiency, where a typical coal plant gives 40% only.
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Saturday, May 4, 2013

Free Energy Generator from Permanent Magnets

There are thousands of videos in youtube describing free energy from magnetic motors. They claim that it is possible to produce free energy from their magnetic motor design. Besides, there are websites that offer free energy generators for sale. Just type magnetic motors in to the google's home page. The results will come with thousands of youtube videos and promotional websites that offer free energy generators. Also you can find several discussion forums sharing different opinions about such automatic free energy generators. Wide popularity of such videos and Tremendous amount of keywords related to magnetic motors forces webmasters to create duplicate contents to drive traffic to their website.

Here's my opinion about magnetic motors or engines. Actually I do not believe in such automatic free energy generators because I believes in Energy conservation theory. There are people who believe it is possible to derive energy from permanent magnets. I too believed it for several years that we can convert energy stored in a permanent magnet using some devices.

Do you know magnets have no energy in it? They are totally neutral. Many peoples have been trying to create a machine, which convert force of a magnet (attractive or repulsive). That's why we are able to see some graphically created videos of magnetic free energy generator in the Internet.

But you should remember that such machine is only an imagination. I had played with permanent magnets to study how this machine works. But I realised that a permanent magnet is neutral. An atom is neutral because it contain equal number of opposite charges. Like an atom a permanent magnet is also neutral because it have two opposite poles, a north pole and a south pole. So by taking a whole magnet as a system the total energy becomes zero by cancelling opposite forces of north pole and south pole. But I wonder why there are people who is still playing with permanent magnets to create a free energy generator.

How an Imaginary Magnetic Engine Works?

Permanent magnets have the ability to exert force on magnetic materials. This attractive or repulsive force can convert into rotational energy. This energy is totally free. No external fuel or work has to be done on the engine.

According to energy conservation theory Energy can neither be created nor be destroyed. So it is not possible to derive energy from a neutral magnet.

But now I don't think the whole idea is foolishness. Because I expect discovery of such engines in future, which could satisfy our growing energy needs.

How? You may have heard that, scientists at CERN (European Centre for Nuclear Research) expects the formation of Magnetic monopoles in world's largest laboratory, Large Hadron Collider experiment.

Magnetic monopoles are one of the mystery of science. Magnetic monopoles are magnets which have only a pole, a south pole or a north pole. CERN scientists expects they can create magnetic monopoles in their proton-proton collision experiment. Magnetic monopoles are thought to be an extreme sources of energy because it is a single pole magnet. They are not a neutral system. Scientists expect it is possible to draw the energy of a magnetic monopole by using suitable machines. Permanent magnets are neutral while magnetic monopoles are reservoirs of energy. If scientists could create such a magnetic monopole it may lead to the long lasting energy source and an energy efficient world.

But there are scientists who believed that monopoles do not exist.They have some reasons behind their opinion. But there are several ongoing researches too. What is your opinion about magnetic monopoles? Do you believe in it? Do you think it is possible to drive energy from such magnets? Then don't be lazy. Be the first commenter on this post.
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Thursday, March 21, 2013

A List of Different Sources of Energy

We know you are very interested to know different energy sources in the world. We are providing you with a  list of energy sources. The list includes renewable energy sources,traditional or conventional energy sources, and latest energy sources. Renewable energy sources are the best option to cross over the energy crisis of 21st century. Most of the developed countries has been forcing companies to adopt renewable energy plants. If you know more sources of energy do not forget to suggest them in the comment section. Help us to improve this list.

Petroleum fuels- A traditional energy source. It is the largest energy source in the world. But we are running out of petroleum oil. 

Coal- Another fossil fuel 

Nuclear energy- Nuclear fission reactors are used to utilize binding energy of nucleus.

Sun is the world's largest renewable energy source. Literally Sun is the master source of energy behind every traditional as well as renewable energy sources. Sun radiates an enormous amount of energy in the forms of light, heat and other radiations. Solar heat
concentrators and solar panels are used to harness solar power. Now a days solar power is gaining more and more attention among governments and even local peoples. But local people try to keep away and watching solar power technology because of expensive equipments.

Wind Power
wind turbine
Wind Energy Image from Gurit by Gurit Composites, on Flickr

Wind power is the world's fastest growing renewable energy source. Actually sun is the energy source behind wind power. Uneven heating of earth surface due to solar heating causes wind. Wind power depends upon energy from sun. There are two types of wind turbines. Horizontal axis wind turbines and vertical axis wind turbines. Horizontal axis wind turbines are very widely used. Even though they are the fastest growing renewable energy source, have several environmental impacts.


Nooksack River, Washington State
Nooksack River, Washington State by Rose Braverman, on Flickr
Hydroelectric Power
I think hydroelectric power is one of the oldest renewable energy technology. A hydroelectric power plant constitutes a dam and a reservoir. The potential energy of stored water can be used to drive a water turbine. The turbine will be coupled with an AC generator. There is a long pipe from the reservoir to the power house. It is known as penstock, which is used to contest potential energy of  in to pressure energy. At the end of penstock nozzles are provided to convert pressure energy of water into kinetic energy. The energy of a water is actually comes from the sun. Sun is the driving force behind water cycle. There are different types of hydroelectric dams classified according to the power of water, applications etc.

Tidal power 

tidal power
Returning tide by Colin-47 on Flickr
An ocean tide is a rise or fall of sea level twise in a day. Unlike solar power or wind power, tidal power is highly predictable. Tidal
power is a promising energy source that can serve power to meet our daily energy needs. Tides are produced either by attraction of celestial bodies or by earth's rotational energy.

Ameresco Biomass Cogeneration Facility at SRS
Ameresco Biomass Cogeneration Facility at SRS by Savannah River Site, on Flickr
Biomass Power
Biomass refers to all the materials that constitute and originate from plants and animals. When biomass burns, it liberates heat energy. The heat energy liberated can be used for cooking, heating rooms, lighting and electrification of rural house hold etc..


Waves III by Peter Kaminski, on Flickr
Wave Power
Another energy source from The Ocean- Second Largest Renewable Energy Source. When wind blows cross the sea waves are produced. Thus wind power is transformed to wave power. This wave power can be effectively harnessed by underwater water tubines. Those wave turbines are designed in such a way that can harness maximum possible power from the wind.

geothermal energy
Hellisheidi geothermal power plant by ThinkGeoEnergy, on Flickr
Geothermal Energy

There are places where high pressure steam is exhausting from the earth crust without any heat supply. This natural steam generators are powered by hot magma. When magma reaches under water reservoirs through weak earth crust water boils and steam is produced. The steam generated can be used to drive a steam turbine coupled with a generator to produce power.


Waves III by Peter Kaminski, on Flickr
Ocean Thermal Energy   

There is a large difference of temperatures between deep ocean and surface. Near to equator this temperature difference is maximum. This difference in temperature can be used to generate power. This is known as ocean thermal energy. Ocean thermal energy harnessing can affect the ocean environment and ecosystem. 


Biological carbon fixation is the process behind biofuel. Producer
organisms or plants can perform carbon fixation. Examples of biofuels are bio-ethanol, biodiesel, green diesel, vegetable oil etc.

Hydrogen- hydrogen is a promising energy source. It is possible to generate energy from hydrogen by direct combustion or fuel cells. 

Fusion energy - fusion of light elements like hydrogen can generate heat energy. 

Cold fusion- It is a fusion reaction taken place in low temperatures. 

Bubble power- it is similar to a cold fusion reaction. Hydrogen nuclei can fused together by tiny bubbles imploded by round water 

Fuel cells- it directly converts chemical energy in a fuel to electrical energy without the application of burning. 

Magnetohydrodynamic energy- MHD will convert thermal energy and kinetic energy directly in to electrical energy. This energy generator have no moving parts. 

Osmotic power- it is also known as salinity gradient power. Power generation is possible when there is adequate difference in salt concentration. 

Ocean thermal energy- there are ocean thermal energy converters which are used to produce power from the temperature difference between deep sea and surface. 

Concentrated solar power- By using lenses concentrated solar energy can be used to generate power. 
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Wednesday, February 27, 2013

How to Make A Simple 6V Emergency Light For Home

inverter board
Emergency Board
Today, I am here to give a complete tutorial on 'how to make a simple 6v emergency light' using compact fluorescent lamp. This lighting device can be easily equipped with a solar panel, then it can be termed as Solar powered emergency light. You can make this device automatic by using a Light Detecting Resister.

We know that some countries are mostly depends on hydroelectric power stations for electricity. In such countries during summer unavailability of adequate water reduces the power production. Energy is one of the most valuable factor, which would effect economical and industrial growth of a country.

Rechargeable BatteryThings you need to create an emergency ligh


1. Rechargeable battery 6V,5A

Rechargeable batteries are used to store electric energy. There are different types of batteries having different capacities. Buy a new sulfuric acid-lead battery having 6V and 5 Ampere capacity. It costs around 5$.

2. Inverter board or Emergency board 6V

The main part of the emergency lamp. Buy a new 6v inverter board or emergency circuit board. There may be a connection for transformer. If there is no facility to attach a transformer on the board you need to buy a adapter 7.5 V 500 mA. There are other 6 wires on the inverter board for battery,CFL,switch.

3. Step down Transformer 9 volt 500mA/ adapter 7.5 volt 500 mA

step down transformerSome inverter board may contain facility to attach a transformer. Transformer is used to step down the AC voltage. There are rectifier circuit on the board, which converts alternating current to direct current. Transformer costs around 1$. Some boards may not contain a rectifier circuit or facility to attach a transformer, you need to buy a ac adapter 7.5 V 500mA to charge the battery or You can simply build a rectifier circuit using transformers and diodes.

4. Compact fluorescent lamp 11w

Buy a new 11 W CFL. It costs around 1$.

5. Switch,2pin wire,connecting wire,plastic box

Costs around 1$

The main part of this 'make' is the inverter board. It costs around 1$. There are wires. At the starting point of the wire from the board there will be texts to guide you where you want to connect it. Among These 6 wires,
Besides there are two points on the board to attach a transformer.

Connect those components properly using soldering iron as shown in figure. Proper connection makes electronic equipments long lasting. Then place those components in a plastic box to make it compact.

Total cost=9$

Connection procedure

1. Connect the transformer to the inverter board.
2. Connect switch,2 pin wire to transformer input,CFL etc
3. Connect the battery

Tips and warming

1. Connections must be properly soldered. Proper connections makes electronic devices long lasting.

2. Do not touch the output wires for CFL, because there may be several hundred volts.

3. When connecting inverter board to battery be sure positive wire is connected to the positive terminal of the battery.

4. Initially Charge the battery for 5-6 hours for better performance.

5. Enclose all the components in a box and place it where children cant reach.

6. Bare connections must be insulated to avoid short circui>

How to Make Automatic Emergency Light

We have discussed "how to make a simple emergency light using CFL at your home". After publishing that post we realized the amount of potential visitors is very large. We conducted a analysis of the traffic sources and keywords to the article and concluded that most of the people need emergency lights working on light emitting diodes other than compact fluorescent lamps. I think this is because of the high energy efficiency of LEDs. Some people searched for solar powered emergency light.

  Here I am going to share a simple emergency light circuit using LED. The 6v battery can be charged by either solar panels or rectifier circuits. This device is based on an LDR (Light Detecting Resistors). An LDR can detect any changes in the intensity of light. In previous emergency circuit there is a direct method to detect the power failure. Here, an LDR is used to detect the power failure. This automatic emergency circuit will trigger an Series of LED's when there is a darkness in a room. The LDR will conduct electricity only when there is light in the room. This is the working principle of LDR based automatic Emergency lights.

Things you should have to build an Automatic Emergency light using LED

  •      Battery - 6v - 1
  •      R1,R2 resistor - 10k - 2
  •      R3 resistor - 1K - 10
  •      T1 transistor - BD140 - 1
  •      T2 transistor - BD139 - 1
  •      VR variable resistor - 50K - 1
  •       LDR -1

Devices and other equipments

  •    Soldering iron
  •    Box to enclose the emergency
  •    Copper wire

Circuit of a Automatic Simple Emergency Light Using LED and LDR

Image Credit

How does it work?

An LDR is made in a way that it only conducts electricity if there is enough light in the room. The resistance offered by the LDR against  the flow of current is inversely proportional to the intensity of light falls on it. So if there is enough light in a room LDR will continue to conduct current and provides high current to the base of  transistor T1. (so T1 is off). Since the base is grounded transistor T2 is also off. If there is a sudden power failure in the room LDR will stop conducting current. At this time transistor T1 becomes forward biased and provides base current to transistor T2. It then turns ON and allows current to flow through the LED.

How to charge the Battery?

How to make a charger for 6v Lead acid battery? Connect the positive terminal of the charger output to the positive pin of the battery. Then connect negative terminal to the negative terminal of the battery.

How to turn this Emergency light into Solar powered Emergency light!

Solar Panel
Solar panel

If you are living in an area that not connected to the grid this Solar emergency light can provide enough light for your home. Just buy a 7.5 volt solar panel from the store and connect to the battery. It does not need any separate charger circuit. That's it. Solar powered
automatic emergency light. Enjoy!!

If any one of your friends is from a region where there is no power supply or lacks continuous power supply, you should suggest this device to your friend. Solar powered emergency light is similar to the ordinary one. But it has a solar panel to capture solar power and convert it and recharge battery. A complete description of this project with full video will be posted
here in coming days. Thank you.


Is this tutorial helpful? Then comment your opinion here! 


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