Saturday, May 25, 2013

How Solar Air Conditoners Work?

We all know that the conventional Air conditioning consumes lot of electricity which in turn releases millions of tons of carbon di oxide, a green house gas which is known to be harmful to environment.  The green house gas emissions have increased by 25% in the last 150 years since the industrial revolution. 

The demand for air conditioning is growing as the temperatures are increasing.  Heat waves cause health problems and some times even death too.   There was news in year 2003 that around 35,000 people died in Europe from a heat wave.  So the demand for air conditioning units is increasing day by day.  But using the conventional electricity lot of green house gases are being released into atmosphere. 

 It is the time now to put a brake to the effects of climate changes by replacing conventional energy with renewable and natural energy like Solar Power.  The only option till now for reducing the energy consumed by air conditioners is to simply turn them off.  But the Solar Air Conditioners take the advantage of the sun shine and use that energy to cool you during the hottest part of the day.  Let us see how a solar air conditioner works..  Let us first know about how a conventional air conditioner works and then go to solar air conditioner.

How a conventional Air Conditioner works?

 You may be knowing that the compressor in your air conditioner is used for raising the temperature of the refrigerant fluid which is necessary to produce cool air. The idea is to use Solar Energy to raise this temperature and reduce the compressor's work load and allow the compressor to consume less energy.   Let us see how a conventional air conditioner works and then go to solar air conditioners.

The Refrigerators and Air Conditioners use a fluid called refrigerant to produce cool air.  The refrigerant works like a sponge, soaking up the heat from indoor air and then transporting it to outside where the heat is squeezed out of the sponge into the air.   The refrigerant flowing through a coil - a series of metal tubes - inside the air conditioner's air handler is very cold ( -6 to +4 degrees celcius).  We all know that heat always flows from hotter place to cooler place.  So if the indoor air at 37 deg. celcius is blowing through the air handler, heat will be removed from the air and absorbed by the refrigerant which is much cooler. So the temperature of the air reduces as heat is removed.   So the air leaving the air handler is much cooler than the room temperature.  

The metal coil inside the air handler is called as evaporator.  The heat absorbed by refrigerant causes it to evaporate and turn it into gas.  Here comes the actual problem.  We know that heat always flows from a hotter place to cooler place.  We want to send the heat absorbed by refrigerant into outside air but if the refrigerant gas is at temperature of say +12 deg celcius,  and outside air is at +26 to +40 deg celcius, this won't work.   We need to find out some way to increase the refrigerant gas temperature to be higher than outside temperature so that the heat absorbed by refrigerant can be dumped to outside.  

We know that by compressing a gas increase its pressure which also increases its temperature.  So the job of a compressor in an Air Conditioner is to compress the refrigerant gas coming from the evaporator coil so that its temperature is raised from 12 deg to 75 deg celcius or more.  With the temperature of refrigerant more than outside temperature, the heat stored in refrigerant is transferred to outside air.

So how the Solar Energy helps

We know that in order to keep the room cooler, the hot refrigerant gas has to be released to outside air and its temperature has to be higher than outside air in order this to happen.  We can send the refrigerant through a solar energy collector before it reaches the compressor, and the solar energy can do a portion of the work of the compressor - heating of the refrigerant.  This allows the compressor to run less and consume less electricity or to operate at lower speed and thus save electricity.    Please see the diagram given here to know about this process.

How the heat is dumped outside?

The hot refrigerant gas which leaves compressor flows into another coil called as the condenser coil.  This coil is similar to car radiator, radiating heat from the hot refrigerant into the outside atmosphere as one fan pulls outside air across the coil.  It is called as condenser coil because the refrigerant gas condenses back into liquid form as the heat is given to outside air.

The refrigerant cools while moving through the condenser coil to around 29-43 deg celcius. Another trick is used to get the refrigerant back to -6  to +4 deg celcius which is necessary for cooling.  As compressing increases the temperature of refrigerant,  we expand it to reduce the temperature.  This is done by forcing the refrigerant through a tiny opening - called as an expansion valve - which allows the refrigerant's pressure and temperature to fall drastically as it comes out from the tiny passage.   

When the refrigerant cools back to -6  to +4 deg celcius,  the cycle repeats.

Oman to use Solar Power to extract oil from oil wells

Oman's oil fields have lot of oil beneath the sands. But it is very difficult and expensive to extract the oil from the wells.  In order to reduce the costs, the Oman's national oil company is now looking towards a new technology - The Solar Power for extracting oil from the wells.

For many years, oil producers depended on steam, created natural gas to heat the rock below the surface and make the oil flow better.  But now natural gas is not easily available. 

 The current process for extracting oil in the oil fields involves burning natural gas to produce steam.  The steam is then injected under ground which heats up the rock and oil and allows the crude oil to flow more smoothly which can be extracted.  22% of the Oman's natural gas is being used for the oil fields and the country is importing natural gas at higher costs.  So the Oman National Oil company is trying to use the Sun's energy to heat the rocks.

The actual process of extracting oil by heating rocks with solar energy uses a system of mirrors which focus the sun light on a pipe colored with absorbent in black color which heats up water which is co produced along with the oil. The system uses very light mirrors made out of aluminum thinner than that of a soft drink can.
Oman has contacted a California company called GlassPoint Solar for building a 4-acre, 7 mega watt solar plant to generate steam for the oil fields. So the solar technology replaces most of the natural gas.   The System has been running for the last one year.  It is only a pilot project.  At full size, which is 100 times of the pilot would replace 80 percent of the natural gas which would otherwise needed.  

How solar power is used for extracting oil from oil wells

The system uses mirrors to focus sun light onto a black colored pipe containing water.  The pipe heats up due to sun light and the water inside gets converted into steam.  The total system is enclosed in a green house to protect the super thin mirrors from dust and wind.  This steam is injected underground and used to push the oil from bottom.

Thursday, May 23, 2013

Advantages and Disadvantages of Solar Energy

We all know that as oil prices are increasing,  people are looking for alternative energy sources to save money.  Solar Energy is one of the alternative energy source which is available free of cost naturally.  Solar energy is nothing but conversion of sun light into usable energy.  Now a days solar energy is used for providing electricity to houses, schools, offices, universities etc.  As the traditional energy prices are on the rise, solar energy use is growing at a rate of 25% per year.  

The solar cell provide the best solution to energy problems where there is no mains electricity or there are lot of power cuts.  Solar power does not create any pollution.  As there are no moving parts for solar power system, it requires little or no maintenance at all.  There are many advantages of using solar power.  Here is a list of advantages and dis advantages of using solar energy. 

Solar energy advantages

  • Solar power source coming from sun is completely free
  • The production of solar electricity does not create any environment pollution. Solar energy does not produce any green house gases like oil. 
  • The sun light and energy from sun does not cost you any thing.  Once you purchase the solar equipment for converting solar power to electricity, it will not cost you anything afterwards.
  • As solar cells does not contain any moving parts, they require little or no maintenance
  • Solar cells last longer life. Most systems have a life span of 30 to 40 years

Wednesday, May 15, 2013

How do the Solar Panels generate Electricity?

Most of us may be aware of the growing importance of Solar Energy in the modern era.  This is because of the shortage of the conventional energy available for all.  There are some remote villages in India where you do not see electricity.  Even if there is electricity connection, there are lot of power cuts now a days.  So the Solar electricity has attained a growing importance.  Many of you may not be knowing how the sun light is converted into electricity by the Solar Panels.  It is very important to know how the Solar Panels generate Electricity.

Solar Panels produce electricity (Direct Current) directly from the sun light.  The Sun light is directly converted to electricity by each solar cell in the panels.They do not need direct sun light to work - they still produce some electricity on some cloudy day also.  

The Solar Panels are made up of circular, rectangular or square shaped solar cells.  These solar panels have p-n junctions.  The solar cells are also called as Photovoltaic cells (PV) and the process of generating electricity from sun light is known as photo voltaic effect.  The P-N junctions are made of semi conductors.  The efficient of these solar cells must be as high as possible to produce more electricity and the efficiency depends on the type of material used for p-n junctions.   The present efficiency level is only 15 to 16 % and in future it may go beyond 25 to 30%.  

The sun light is made of photons.  The photons convert into electrical energy when the p-n junctions are placed in sun light.  When the photons of sufficient energy strike a solar cell, they knock out free electrons  in the silicon crystal structure and force them to travel in external circuit ( battery or a DC load) and then return them back to other side of solar cell to start the process again.

The voltage from a single solar cell is about 0.5 Volts with amperage output directly proportional to the cell's surface area.  It is roughly 7 amps for a 6 square inch area.  Normally 30 to 36 solar cells are wired in series in each solar panel.  This produces a solar panel with a 12 Volts nominal output ( 18 Volts peak output) which can be wired in series or parallel with other solar panels to form a complete solar array for charging a 12V, 24V or 48V Battery banks.  Here is a video showing how a solar panel generates electricity.,

Tuesday, May 14, 2013

Types of Solar Panel Installations

There are mainly three types of Solar Panel installations.  Here is a list.

Fixed Solar Panel mount:  This is the simplest and least expensive type of solar panel mounting.  The system is completely stationary.  The solar panels should always face the equator ( due south in the northern hemisphere).  The true south varies from magnetic south.  The angle of inclination of the solar panels in degrees should be set to about your latitude value. If it is slightly more than your latitude value, it will favor the winter sun. If the angle of inclination is slightly less than the latitude value, it will favor summer sun.

Adjustable solar panel mount :  You can change the angle of inclination of an adjustable solar panel mount 2 or 3 times in a year to account for lower angle of the sun in winter.   One good thumb rule is  Latitude + 15 degrees in winter and Latitude - 15 degrees in summer. This increases the over all solar panel output by 25%.  It is better to set the winter position in October and Summer position in March.

Tracking Solar Panel Mounts:  The tracking solar panel mounts  follow the path of the sun during the day in order to get maximum sun light.  A single axis tracker tracks the sun from east to west and a two axis tracker tracks the sun daily east to west and also the seasonal
declination movement of the sun.  The tracking solar panel mount is is the most efficient type of solar panel mount but it is the most expensive also. 

Monday, May 13, 2013

What are Solar Panels

Solar Panels are Eco Friendly electric generators.  The solar panels generate free power from sun light by converting sun light into electrical energy.  You can see a collection of individual silicon  cells in each solar panel.  The solar panels generate electricity with no moving parts, zero emissions and no maintenance. 

The photos ( light particles) produce electric current as they strike the surface of the thin silicon wafers.  A single solar cell generates about 0.5 volts.  A normal 12 Volts solar panel has 36 cells wired in series to produce about 17 to 18 volts peak output.   A 24 Volts Solar Panel contains about 72 cells.  When a solar is charging the battery, this 17 volts drops to around 12 to 14 volts ( for a 12 V solar panel) which results in 75 to 100 watts for a panel of this size.  A solar panel of 12 V has dimensions of 25 inches by 54 inches.

If you want to increase the current capacity ( more power) of a solar panel, you need to wire multiple solar panels in parallel.  If you want to increase the voltage for 24 V, 48 V or so, you need to connect the solar panels in series.  One advantage of using higher voltage output solar panels is that you can use small wire sizes for transferring electric power from panels to the charge controller or battery.  

Types of Solar Panels

 Basically there are three types of solar panels available in the market.  The details of three types of solar panels is listed below.

Monocrystalline Solar Panels :  These are the most efficient and expensive solar panels and made with Monocrystalline cells.  These solar cells uses pure silicon and it involves a crystal growth process.  Long silicon rods are cut into slices of 0.2 to 0.4 mm thick discs or wafers which are then processed into individual cells which are wired together in a solar panel.

Polycrystalline Solar Panels:  These Solar Panels are also called as Multi-Crystalline Solar Panels are made with Polycrystalline cells and are a little less expensive and less efficient compared to Monocrystalline type.  This is because the cells are not grown on single crystals but in large blocks of many crystals.   These are also sliced into wafers to produce individual cells which make up the solar panel.

Amorphous Solar Panels :  The third type of solar panels is the Amorphous solar panels which are not really crystals but a thin layer of silicon is deposited on a base material like metal or glass to create a solar panel.  These solar panels are very much cheaper but their energy efficiency is very less and so more area is required to produce the same power compared to above two types.  

Location to install Solar Panels

When you decide to install Solar Panels, the location has to be planned properly in order to get the maximum sun light on them. You should make sure that no shadows fall on the solar panels installed during the peak sun light hours ( say between 10.00 AM to 04.00 PM).  The shading of solar panels reduce their output drastically but it could also damage them.  Some suppliers  say that their solar panels can withstand shading.  So it is very important that choosing a good location without any shadows is essential requirement for a solar panel installation.  So if there are any obstacles which give shadows on the panels can be removed.

The temperature and wind loads are also important factors to be considered.  We know that we have to install solar panels in sunny and non-shady locations to get maximum output.  But heat building up is also a problem for solar panels.  The efficiency of solar panels reduces as temperature rises.  So the solar panel mounting system must allow for spacing around individual panels for air circulation so that it allows air cooling in the hot sun to reduce temperature of panels.  By allowing air flow around the solar panels, they not only become cooler  but the wind resistance also reduces.

What is Solar Energy?

Solar Energy is nothing but the energy from Sun.  There are two types of solar energy - Thermal energy and Electric energy.  

Thermal Energy 

You can see thermal energy everywhere.  It heats our earth, our bodies and our homes.  The thermal energy dries up our clothes and also we get products from it like sun-dried tomatoes.  All this for free...  The Thermal energy is also used to heat water for house hold use and also water in swimming pools. 

Electric Energy

The electric energy uses the sun light for producing electricity by using solar cells or photovoltaics.  It can be produced in three ways.
  • Stand alone system
  • Grid-connected system
  • Back up system
The stand alone system is also called as Solar Home System.  This system is not connected to the grid.   This kind of systems are normally installed in remote areas where you do not find electricity.  It is very cheap to install solar energy system than laying cables for electricity to the remote site.  

The Grid-Connected system is a system where the utility supplied electricity is connected to the house and at the same solar energy is also connected to the house.  Electricity is supplied firstly from solar energy  and if required any need is there, it is supplied by grid.

Back up is a system connected to an unreliable grid or one of poor quality.   These  types are usually installed in areas where a lot of power blackouts occur. A small system will service the most important electrical appliances and lights, but a bigger system will be required to keep the fridge running during a blackout.

Sunday, May 12, 2013

What is a Charge Controller in a Solar System

What is a Charge Controller?

 As we know that  we get more voltage from the solar panels as the brightness of sun increases.  The excessive voltage could damage the batteries if the batteries are directly connected to the solar panels.  A charge controller is a device which is used to maintain the proper charging voltage on the batteries.  When the input voltage from the solar panels increases, the charge controller will regulate the charging to the batteries so that over charging is prevented.  A Charge controller regulates the voltage and current coming from the solar panels to the battery.  Most of the 12 Volts solar panels produce 16 to 20 volts and if connected directly to the batteries will damage them due to over charging.  Most of the batteries need around 14 to 14.5 volts to get fully charged.

Modern Charge Controllers 

Most of the modern charge controllers undergo what is known as 3-stage charge cycle which is shown below.
  • Bulk Phase : During this phase of charge cycle, the voltage rises gradually to the bulk level ( normally 14 volts) while the batteries draw the maximum current.  Once the Bulk level of voltage is reached, the absorption stage starts.
  • Absorption Phase :  During the absorption phase, the voltage is maintained at the Bulk level for some specified time which is typically 1 hour while the current gradually tapers off as the batteries get charged up. 
  • Float PhaseDuring this phase the voltage is lowered to a float level ( normally 13.3 volts to 13.7 volts) and the batteries draw a small current until the next cycle.
    You can see the relation ship between the current and voltage during the above 3 phases of charge cycles in a graph which is shown below.

Is the charge controller always needed?

No,  it is not always needed.  Generally a charge controller is not required for a small systems like 1 to 5 watt solar panels.  A general rule is that if a solar panel puts out about 2 watts or less for each 50 battery amp-hours, then a charge controller is not required. 

Why 12 volts solar panels actually produce 17 volts 

You may get a doubt "Why solar panels are not designed just to produce 12 volts".  The reason is that if you design a solar panel to produce just 12 volts,  the panels will provide power only under perfect conditions and full sun.  This is not the situation in most of the places.  The panels have to produce extra voltage so that when the sky is cloudy and sun is low, you should still get some output from the panels.  A fully charged 12 Volts battery is around 12.7 volts at rest so the solar panel has to at least produce more than 12.7 volts in worst conditions.  

One thing to remember is that the solar panels work best at cooler temperatures.  A solar panel rated at 100 watts at room temperature produces 83 watts at 110 degrees temperature.

A solar charge controller regulates the 16 to 20 volts output of the solar panels down to what the battery needs at the time.  It may vary from 11 volts to 14.6 volts depending on the state of the charge on the battery, the type of battery and in what mode the controller is in and the temperature. 

The charge controller is installed between the solar panel array and the batteries.  The charge controller maintains the charge on the batteries using the 3 stage charge cycle described above.  The power inverter can also charge the batteries if it is connected to the AC utility power.

Summary :  If you are  using four 80 to 100 watts solar panels,  your charge controller should be rated up to 40 Amps.  Even though the solar panels normally do not produce that much current, there is an 'edge of cloud effect'.  Due to this phenomenon I found that my four 7.5 amps panels ( 4 x 7.5 = 30) pump out more than 35 Amps which is well over the rated 30 Amps maximum. 

Friday, May 10, 2013

What is needed for Solar Power System Installation

General Requirement of Solar Panel Installation at homes

Are you planning to install solar power system for your house?  Do you know what is required and where to start?  If you plan to install a solar power system for your house, then you need to know some basic requirements for installing solar power system.

Besides from installing solar panels on the roof top, some additional equipments are needed for providing power to your house from solar energy.  Once you buy all the equipments and install the solar panels and they are working, there will be little or no maintenance and no additional cost.  Let us now see what is the general requirement for installation of Solar Energy system.

Once you have a general understanding of how the solar energy system functions, it will be much easier to choose the right parts.  In this article you can see the brief description of a standard grid tie system ( or on the grid system).  Staying connected to the power grid means that you still receive the power from the utility company and you can even sell your excess power back to the utility company.

What are the main components of a solar energy system for your house

In the on the grid system,  the electricity is generated by many solar modules ( or PV solar panels).   There will be a shut off switch which separates the panels from the rest of the system.  This is required for you to be safe in case of any repairs.  The next equipment in the list is the solar inverter which turns the Direct Current (DC) from solar panels into Alternating Current (AC) for the house.  From the inverter, the power goes to the circuit breaker box and distributed through out the house. A power meter which is capable of measuring power going into or being pulled from the grid will measure amount of electricity which is needed or sold back to utility company.

Choosing the correct solar panels

You are supposed to know few basic things before proceeding to design the solar power system for your house..  You should know how much energy is needed to be produced, amount of space available on roof top,  and what you can afford to buy.   The best starting place is to know how much you consume in a month.  With this information, you can estimate what is the size of solar array is needed to produce the required amount of energy, or how much energy can be produced in a given place available or how much can be produced with the money you have.

Once you know about your monthly target output in KWh, it is very easy to calculate the size of solar array needed.  An average house may need about 600 KWh every month but it differs from place to place.  Divide this number by the peak sun hours you receive each day to know the size of your solar system.  The Peak Sun Hours are the number of hours per day where the solar irradiance equals to 1000 watts/square meter.  The average peak sun hours at any place is 5 hours.  An example would be,  if you use 1000 watts daily, and you receive 5 hours of sun light per day, then you need a 200 watt panel to completely cover your usage. 

Now take your monthly KWh number ( 600 Kwh) / 30 days / month = 20 Kwh per day. Do you know what size of solar array makes 30 KWh per day?  This depends on peak sun and let us take it as 5 hours.  So 20 KWh / 5 peak sun hours = 4 KW array or 4000 watts.  For a 4000 watts array, you need 20 Nos. of 200 Watt panels, or 16 Nos. of 250 Watts panels. 

Now you know how much power is needed, start designing the solar array.  There are two different kinds of solar panels. -  traditional crystalline solar modules and thin film solar panels.
Crystalline are large modules and expensive but more efficient than thin film panels,  The thin film models comes on a flexible roll of metal or plastic which can be applied on any flat surface like metal roof.   It is very simple to install this kind of panels.  But if the place is less on the roof top, then choose the high-efficiency crystalline panels.

Thursday, May 9, 2013

Odissa Government giving Subsidy for Solar Systems in homes

Are you upset with frequent power cuts and increasing power bills and do not know what to do?  There is a solution for every thing.  The best solution is to go for solar energy.  But installing solar power systems is a little bit costly.  But if you opt for solar electrification through solar energy, it will ensure better electricity supply and a relief from power cuts.  So the Odissa Renewable Energy Development Agency (OREDA)  is encouraging people of their state to opt for solar energy by providing subsidy for installation of home solar power systems.  So all the people in Odissa can make use of this opportunity and try to install solar Power Systems in their homes to avoid frequent power cuts and reduce their power bills.   The other state governments are also encouraging installation of home solar power systems by giving subsidy for the work. 

The capital cost for 1 KW power plant is rs. 2.5 lakhs and the consumer cost is Rs. 1.7 Lakhs after subsidy of Rs.80,000.  There are people who installed Solar Power systems of even 7 KW and obtained huge subsidy from Government.

The solar power supply system is very much successful in interior areas of the state where electricity has not yet reached.  The OREDA has installed solar power systems in more than 400 remote villages.

Cool things about Solar Heating

Most of the people may be familiar with solar photovoltaic panels but many do not know that solar power can be used for heat in their homes.  Active solar heating user the solar power to heat air or liquids which transfers the solar heat directly into the internal space for later use.  There are many types of heating systems like radiant heating, absorption heat pumps, boilers, or forced air heating.  But solar heating systems often supplement these heating systems.  

Solar heating has become very important now a days than ever before.  The natural gas and oil which are burned to heat our homes are limited.  These fuels are more over costly.  But solar power is available free of cost and is available world wide for any one.  If you burn natural gas or oils for use in our house heating systems, they produce air pollution.  Even electric water heaters produce air pollution. So if more people start using solar energy to heat their homes and water, the environment will be more clearer.

Here are some of the cool things about active solar heating.

  • Active solar heating systems are the most cost-effective in cooler climates which have good amount of solar energy.
  • You can either choose liquid or air systems for heating your homes which help you to supplement forced air heating systems.
  • The commercially sold solar heating systems comes with a warranty of 10 to 15 years but they will work even for many more years
  • The solar heating systems reduce the air pollution and green house gases which generally come from the use of fossil fuels for heating and electricity production
  • When a solar water heater replaces an electric water heater, the electricity used for 20 years represents more than 50 tons of carbon di oxide emission.  The carbon di oxide traps heat in upper atmosphere and so contributes to green house effect.  Hence use Solar water heating systems for a clean and green earth.

Wednesday, May 8, 2013

Solar Energy from Sun

The solar energy is the light and heat radiated from the Sun.  It has been used by humans since ancient times,  Some of the solar energy technologies include solar water heating, solar electricity, solar artificial photosynthesis etc...  These technologies make significant contributions in solving the most urgent energy problems the world especially India faces now.

Our Earth receives about 174 petawatts (1 petawatt = 1015 watts)  of solar radiation at the upper atmosphere.  Nearly 30% of this energy is reflected back to space while the rest of it is absorbed by clouds, oceans and land masses.

Green plants convert solar energy into chemical energy which produces food, wood and the bio mass.   The total solar energy absorbed by Earth' s atmosphere, oceans and land masses is approximately 3,850,000 exa joules ( 1 exa joule = 1018 joules) per year.   The amount of solar energy reaching earth's surface in a year is so vast that it is twice as much as the energy that is obtained from all of the Earth non-renewable resources of coal, oil, natural gas etc.

 Applications of Solar Energy

Solar energy is the light and heat radiated by the Sun.  The solar energy that reaches the surface of Earth can be used for producing electricity or heat through the use of solar collectors.
For example a closed car can be viewed as a solar collector - the light energy which passed through the window glass of the car is absorbed inside the car and converted into heat.  The amount of solar energy falling on an area of the size of a basket ball field, in thermal energy terms is equal to about 650 barrels of oil in a year. Solar energy is a renewable energy whose use does not affect the future supply.

The solar energy can be categorised in two ways - Heat and Light.  The solar energy is used by us in many ways everyday.  For example when we hang the laundry outside to dry in the sun light, we are using the solar heat for drying out clothes.  The plants make their food in presence of sun light.  If there is no sun light, plants will die.  

There are varieties of products that use solar energy.  These products are called as solar devices or solar thermal collectors. The Solar thermal  technology use the solar heat to heat water or air.  Let us see some of the applications of solar energy in various fields

Solar energy applications for houses

There are a lot of advantages of solar energy for homes.  Solar energy is used at home for water heating with solar heaters. The solar panels installed on roof tops of our houses are used to generate electricity from solar energy.  The batteries store energy captured during day time and supply power through out the day.  This helps us to reduce the expenditure on electricity as well as help us to have power during power cuts.
Solar Energy for Industrial applications

The solar energy  can be used in offices, ware houses and industries for supplying power.  The Solar energy can be used to supply electricity for Radio and TV stations.  Solar energy can be used for supplying electricity to light houses and warning lights for aircraft.

Solar energy can also be used for power generation in remote places like schools, homes and other places where there is no electricity available.  The water pumps in remote areas can be run on solar energy.

The solar energy can also be used for public transportation system like buses and light rails and trolleys.