Solar cells are electrical devices that generate electricity from the energy of light. As most of us are aware the main source of solar energy is the Sun and solar cells or photoelectric cells are used to convert the energy of the sun into electricity. These solar cells form a basic part of the actual solar panel, which generate electricity by emitting electrons when exposed to sunlight. This process of generating electricity is called Photovoltaics. Solar Cells, which act as semi conductors in this process are formed up of several photovoltaic materials. Depending on the materials used, these solar cells differ in cost, performance and efficiency. The traditional solar cell in use is the p-n junction solid semi conductor. However, there are several disadvantages and limitations to the p-n junction devices such as the cost involved, thick layer of silicon required and expensive silicon processing.

Dye Sensitized Solar Cell Origins

The dye sensitized solar cell was developed in late 60’s and early 70’s has turned out to be one of the cheaper alternatives to the more conventional p-n junction solar cells. Dye Sensitive Solar Cells are a formed as a result of combining photo sensitized anode and a photo electrical chemical cell such as electrolyte, gel or liquid. dye sensitized solar cells are usually cheaper because of the less experience materials used as opposed to expensive metals such as platinum used in conventional solar cells. This makes the dye sensitized solar cell not only cheaper for the buyer but also for the manufacturer. Although, the conversion efficiency of a dye sensitized solar cell is less when compared to other thin film cells, the cheaper price covers up for the loss.

The latest dye sensitized solar cell in use was invented in 1991 by Michael Gratzel and Brian O’Regan. This dye sensitized solar cell consists of a glass plate with one side consisting of the transparent anode made up of tin dioxide and the other side is titanium dioxide nanoparticles forming the porous layer. This glass plate is then immersed in an electrolyte solution or a dye which is a mixture of molecular sensitizers and solvent. A thin layer of the solvent or dye is left intact with the titanium dioxide nanoparticles. A separate plate that is spread with a thin layer of electrolyte on one side is prepared and both the plates are joined to prevent electrolyte leakage. Unlike the traditional solar cells, the task of charge transport and source of photoelectrons are separated in a

dye sensitized solar cell

and are carried out by the semiconductor and the photosensitive dye respectively.

Dye Sensitized Solar Cell

Dye Sensitized Solar Cell Comparisons

A dye sensitized solar cell is particularly attractive when compared to the other thin film solar cells and traditional silicon panel solar cells because of the low cost, easy to manufacture technology and the mechanical robustness of the solar cells that lead to higher efficiency when the temperatures are high. However, there will be some limitations with a dye sensitized solar cell, such as the use of liquid or gel or electrolyte solution which are unstable at higher temperatures and also contains volatile organic compounds that are hazardous to human health.

Thin Film Solar Cells (TFSC) are also known as thin film photovoltaic cells (TFPV) are ultra thin solar cells that convert the suns radiated spectrum into electricity using the photovoltaic principle. Thin Film Solar Cells are used in a wide variety of installations but were primarily designed for calculators, watches and small power rechargeable batteries.

How Are Thin Solar Cells Made?

Thin Film Solar Cells are created by layering photovoltaic material onto a substrate material. Depending on the output required more than one layer can be applied. Thin Film Solar Cells vary in thickness from nanometers to tens of micrometers. Thin Film Solar Cells are usually categorized by the materials that are used to create the cells. There are four main materials employed but of the four two are more common than the others. The most common material employed, is:

Thin Film Solar Cells

Amorphous Silicon (a-Si)

An Amorphous thin film cell uses Nanocrystalline (nc-Si), Protocystalline, or Black Silicon in its manufacture. This material differs from the more usual Monocrystalline or Polycrystalline wafer used in the manufacture of normal solar panels. The silicon is layered into the substrate material by a technique known as chemical vapor deposition although other means are being explored. The next common material used in thin Film Solar Cells is:

Cadmium Telluride ( Cd-Te)

These types of Thin Film Solar Cells uses two common materials Cadmium and Telluride, and is slightly more expensive to produce than the Amorphous Thin Film Silicon solar cells because they are both rare earth elements. Another less common group of materials is:

Copper, Indium, Gallium, Selenium (CIGS)

The number of rare earths involved in this photovoltaic combination makes raises production costs. However of all the combinations of rare earths this one is thought to be able to achieve the holy grail of grid parity given sufficient demand and production. Finally the last combination of elements is:

Thin Film Silicon ( TF-Si)

This is Silicon that is reduced to molecular size and then deposited on the substrate material. The output of this type of Solar cell is slightly inferior to the rest of the above. Nevertheless it was one of the first materials to be employed in manufacturing Thin Film Solar Cells.

Thin Film Solar Cells Problems

One of the most pressing problems facing the Thin Film solar Cell industry is the availability of the rare earth elements required for this technology. Virtually all the rare earth elements at this time are mined and refined in China. Until other sources such as Africa come on stream the price of these rare earth elements will always remain high.

Thin Film Solar Cells are now becoming main stream and are being incorporated into buildings both installed on the roof and in the wall panels. Thin Film Solar Cells are very rugged and light and can be semi transparent for use to cover windows and other areas of glass. The Thin Film Solar Cells also act as window tinting while they are producing power.

The future of solar cell is definitely Thin Film Solar Cells. The higher electrical output of these panels and their ease of installation make the object of achieving grid parity evermore closer.

Polycrystalline Solar Cells

Polycrystalline solar cells have become very popular in most countries that are aiming at power saving and would like to opt for more environmental friendly ways to generate power. These polycrystalline solar cells utilize the natural sun rays to generate power that is essential for consumption. Most people use this form of energy for domestic purposes as well as small businesses that do not require too much energy in production for long hours. It is however possible to generate energy to use in industries but this may require more polycrystalline solar cells to be installed which might be expensive for the small businesses. Using polycrystalline solar cells is an efficient way to reduce production costs and reduce electricity consumption if an industry opts to use these solar and are able to install them. In rural areas the initial cost of installing these polycrystalline solar cells is cheaper compared to electricity because the initial cost of electricity connection is expensive.

Rural residents are required to pay high connection cost that include the wiring and post fixing charges from the transformer to their homes; this makes the rural residents prefer these polycrystalline solar cells.

Polycrystalline Solar Cells

Once they are installed and ready for use, the client is able to enjoy uninterrupted power supply that is usually associated with electricity, the consumers are able to enjoy unlimited power consumption without having to worry about the high power bills that they are forced to pay every month for power consumption. This is economical for consumers because the only cost involved is the initial installation cost and no other monthly charges are involved.

Polycrystalline Solar Cells Output

Polycrystalline solar cells give the best output when they are installed in areas with high amounts of sunshine at least half a day, this way they are able to tap and save enough energy for consumption. Polycrystalline solar cells are of a dark color and this enables them to absorb the maximum energy from the sun rays and store it with little energy being lost. They are weather proof in that they do not spoil no matter the weather condition; they remain in good condition even after getting rained on. Polycrystalline solar cells have a tempered glass that is covered with aluminum frames that are very durable and can withstand all weather types and last for a long duration of time. They have a power inverter that enables high volumes of power storage that can be used for a long time so the consumer does not have to worry about power shortage at any time.

Polycrystalline Solar Cells

Polycrystalline solar cells are easy to install because they come with a free manual that is designed to help the consumer to easily use it. Polycrystalline solar cells also come with a wiring kit that enables the consumer to use the energy from the solar for various purposes that include lighting, water heating, powering plants and also for running other household facilities that require power. Polycrystalline solar cells are however not a very popular source of energy and therefore, people need to be educated more on its importance.

Solar Cells For Sale

Monocrystalline solar panels are one the most efficient commercially viable photovoltaic solar collectors, but not necessarily the first choice for every home!

Monocrystalline photovoltaic electric solar energy panels have been the go-to choice for many years, and are among the oldest, most efficient, and most dependable of technologies. If you’ve ever seen black or iridescent blue panels on a roof or powering a device, they were probably monocrystalline panels. Each module is made from a single silicon crystal, and is more efficient, though more expensive, than the newer and cheaper polycrystalline types.

Here’s a look at the benefits of Monocrystalline Solar Panels.

These are generally considered the workhorses of the solar power market, and most people will choose monocrystalline panels due to their ready availability. These panels are easily identifiable, made up of uniformly stacked rounded cells. Because they’re made from just one crystal, not multiple crystals fused together, the process of making them is one of the most complex and costly ones around. That means every panel will cost more.

However, that increased cost is buying additional efficiency, meaning one panel will produce more power than lower priced options. If space is a concern (which it often is with solar panels), monocrystalline will be the best type to use. More wattage per square foot can be delivered with these panels. The average 175 watt panel is about sixty-three inches in length, thirty one inches in width, a little over an inch high, and weighs thirty-three pounds, with an aluminum frame. The lifespan of a monocrystalline cell is a minimum of twenty-five years and can be more than fifty, making them a worthwhile investment for long term use. These panels are extremely fragile, however. That means a rigid mounting is a must.

Like other types of solar panels, monocrystalline solar modules suffer a reduction in output once the temperature from the sunlight reaches around fifty degrees Celsius/a hundred and fifteen degrees Fahrenheit. Reductions of between twelve and fifteen percent can be expected. These are lower than the reductions in output experienced by polycrystalline cells, but they still need to be factored into the calculations and design for any solar power system.

For those putting together a long term solar setup who want to know they have access to the best and most reliable panels on the market, monocrystalline types are probably the best bet. They’re costlier than polycrystalline options, but their longevity, performance, and efficiency mean that they’re a good buy over a longer period of time. When you want to be sure you’re producing the highest wattage per square foot, these are the modules to rely on.

There is a great demand for solar panels across the world and some of the world’s leading companies are coming up with innovative ideas to design most efficient solar panels.

Most Efficient Solar Panels Manufacturers

The current initiative is taken up by few known companies such as Sanyo Electric and Sun power which is world’s leading brands in the manufacture of Solar panels. Sun power, a Silicon Valley manufacturer of high efficiency solar panels have recently come up with a range of models which can produce efficiency to as good as 20.7%. Actually higher efficiency results in low or cheaper costs of the solar panels. Also the most efficient solar panels are those which produce more energy utilizing less area. The efficiency tells us how much of actual needed electrical energy is produced from the total input of solar energy. There is a competition amongst various companies who want to produce most efficient solar panels, which are as good as 40% energy efficient while others claim to have even more of it. However most of the commercial silicon cells range up to 15% percent of the total energy. According to a Company from San Jose, California the E 19’s range (manufactured by Sun power) provides a higher efficiency by employing an antireflective coating which captures greater amount of off-angle light and by using 3 percent more surface space per cell. This as compared to the conventional solar panel gives in more energy efficient solar panel features. This product has already captured a lot of attention in the market from plenty of customers and will gain double of what it has achieved now.

Most Efficient Solar Panels Available

The other most efficient solar panels which have an efficiency of nearly 40% are highly expensive, splendidly designed and highly complex models. Scientists therefore are now experimenting to bring out results that will make such solar panels cheaper, less complicated and easily handled by people who use them. According to them they tap the nano-technology features and combine it with the built up of the latest designed solar panels. Although the device is easy to create scientists still have some hiccups in tapping the energy productively. As soon as that is done more and more people can be benefited by such a development.

As for now the silicon solar panels are used profusely by most of the manufacturers around the world.

Most efficient solar panels can be manufactured at home also. There are many eBooks available on the Internet which gives clear instructions on how to make these solar panels.

Understanding the solar panels’ function is as good as understanding the free flow of electrons through the circuit. This is because a solar panel generates electricity using the similar principles of electronics as standard electrical objects or chemical batteries. Whether it is the space station or solar powered calculators – the theory of function of the solar panel remains same every where. For electricity to flow in any electrical device it is imperative that the positive charge be created which generates it. In solar panels this is generated by combining silicon with an element such as ‘boron’. The two plates are joined together with the help of conductive wires which catalyses in running electricity through them.

How Does A Solar Panel Work Efficiency Wise?

Before we use the solar energy for various uses its important to know the efficiency of the solar cells for more and more generation of electricity since we know that this energy is an inexhaustible one. Solar panels are tremendously used as house hold appliances with greater efficiency. May it be in cooking, boiling, microwaving, air conditioning or refrigerating solar panel efficiency is simply abundant, renewable and reasonable for modern living people. With the home solar appliances only 20% of the total energy is converted in to electrical energy which means that the solar efficiency that we actually get with these devices is nearly 20%. With the use of electrical bulbs and tubes the efficiency further drops to 5%.

Countries like USA and Australia have plenty of solar panel manufactures. These panels can be used in running products ranging from the water heater, solar lamps, street lights, and solar cells to solar cookers etc. The solar panels come in kinds such as photovoltaic solar panels, a-Si- thin-film solar panels depending on the power that they produce ranging from a mere 20 watts to 500 watts. Countries like china produce solar panel products which are energy efficient and come in reasonable rates.

The latest high technology solar panels hail with an efficiency as good as 20.7% which is more than the average output of 19%. These high power solar cell series have a thin single crystalline wafer of silicon surrounded by ultra-thin layers of silicon. The new panels use AG coated glass which provides an important feature of ‘light-trapping’, which gives more efficiency in less sunny areas. The smaller areas can get tremendously benefit from these high energy solar panels with more efficiency.Now that  the question “how does a solar panel work” has been answered you can pick one up for your home today.

Solar energy has replaced the conventional energy resources with its potential results and capacity. It leads the list of renewable energy resource. There are many methods to create and store solar energy. Let us discuss the six different types of solar energy in this article.

Solar cells: Whether it is a pocket calculator or a high-end electronic device, you might have seen solar cells playing the main role. These cells are arranged in various patterns or arrays which are called as panels. The solar panels are made of Silicon and act as semiconductors. They are useful in generating electricity using the sunlight.

Solar Fibers: This technology uses solar tape made of Titanium dioxide. Their functions are similar to that of the solar cells. The only difference which distinguishes solar fibers is that it does not use silicon. The solar tape is used in building materials, manufacturing cars and clothing.

Solar Updraft Tower: The basic concept of solar updraft tower is to drive turbines using the solar energy. Air is left to pass through a green house kind of structure. It gets heated along the passage and is channelized through a tower. The hot air rises up and drives turbines.

Solar Pond: The main purpose of a solar pond is to produce heat and not electricity. It is big structure with three layers. The topmost layer has low salt content. The middle layer has medium amount of salt which acts as an insulator. It prevents heat convection in the water. The bottom most layer consists of high level of salt which traps the heat. The temperature of this layer can go very high at times. The trapped heat is used to warm up buildings, homes or produce electricity.

Solar Chemical: Chemical reaction is used in this method to generate electricity out of sunlight. Not much can be discussed about the use of this method as it is still in its nascent stage. All we know is most of the researches are based on photo electrolysis of water.

Energy Tower: This method is very much similar to solar updraft tower. Water is sprayed on the top of the tower. The water is then evaporated and cooled inside the tower. The cold air gets heavy and lands on the turbines driving them smoothly.

Though many researches are being carried in this field, solar cells are the ones which are widely used and known by common man.

There are many challenges striking our planet every now and then. One of them is global warming and intensive pollution. The ozone layer that protects the earth from the harmful UV rays of the sun is getting worn out and damaged every day. Who is responsible for the destruction? Of course, we human beings! We can stop this destructive act by taking few measures. One of them is using renewable energy resources such as solar power.

Until few years ago the tremendous heat and light emitted by the sun was unnoticed. Solar energy is constant and free source of energy which can be harnessed continuously. Utility companies and homes have huge solar panels set up to receive unpaid energy from the head of the solar system. Though there is much to say about the advantages of solar energy, only drawback is consistency. The solar cells work well on sunny and bright days whereas on a cloudy or foggy day they do not supply constant energy. To avoid this solar energy has to be stored. There are few methods to store solar energy. Let us discuss them in detail.

Photovoltaic Solar system

The solar energy can be stored using a photovoltaic system in 2 different ways – Grid and Battery banks. The grid uses net-metering. When excess of solar energy is produced it is sent to the grid. During this process the meter rolls backwards and when you use the stored energy, the meter rolls forward.

Battery Bank

A battery bank system constitutes of 4 main components:

Battery bank: It looks similar to the car batteries. A group of batteries are tied up to form an energy bank. They are devised to tolerate charging and discharging actions of solar energy.

Charge Controller: It is a controlling device set in the instrument. It prevents the battery from getting over charged.

Main DC Disconnect: It is a DC breaker that disconnects the batteries from the inverter for servicing purposes.

System Meter: Just like any other meter it displays the performance and the status of the solar panels.
Battery bank storage suits home and office.

Solar Thermal Storage

Solar Thermal storage systems are used for solar pool heating, solar space heating and solar water heating.
Solar water heating systems uses huge tanks filled with water to capture solar power. Solar space heating systems use water tanks and thermal mass to store solar energy. Thermal mass captures the energy during the day and releases it at night. Solar pool heating system uses the water in swimming pools to store energy.

Solar power is an alternative source of energy that substitutes all other conventional sources. The radiant rays of the sun are captured by solar cells which are placed in an array. They convert the rays into electricity which can be used for running utilities and lighting homes and offices.

Solar panels have become the prime slogan of green revolution. They not only balance the environment and the human existence, but also curtail the extinction of natural resources. The bright and glorious future of solar panels lies in the hands of the consumers who understand its benefits.

Photovoltaic Cells (PV)
Solar cells or Photovoltaic cells absorbs the sunlight and produces energy. They contain semi-conductors which converts the light into energy instantly. PV cells are reliable and long lasting. They do not require special maintenance. If used properly, they would last for around 20-25 years. Not all the solar panels have similar kind of cells. Though the technology is ever growing there are 4 types of cells which are used widely in the solar panels:

1. Thin films

2. Crystalline Silicon Cells

3. Thermo photovoltaic Solar Cell

4. Concentrators

Thin film solar cells: These cells are thin; light weighted and easy to assemble. The amorphous silicon thin film is just 1 micron thick. These cells are very affordable. Non-silicon semiconductors such as copper, Gallium and Selenium are used in thin film solar technology.

Crystalline Silicon Cells: Crystalline solar cells are used in huge solar power plants. They are very similar to semiconductors. They contain 2 layers- negative layer and positive layer. These layers create electric field. Polycrystalline silicon cells are made up of tiny silicon crystals. Though they are small in size, their efficiency is uncompromised.

Thermo photovoltaic solar cell: Unlike the other cells these cells convert heat into electricity. These cells use semiconductors which absorb infrared rays and UV rays emitted by the sun. The best part of these cells is that they generate electricity not only from the sun rays, but also from any source of heat. Thermo photovoltaic cells are used in furnaces and charging heavy duty batteries. They are easy to maintain and pollution free.

Concentrators: If you are aware of the functions of optical lens, you can understand the functions of concentrators better. The lens placed in the panel concentrate the sunlight in a single area to increase the production of electricity. If compared to other cells the performance of concentrators are more effective and efficient. These cells are used in high end technologies such as space craft and satellites. To maintain the direction towards the sun, tracking instruments can be installed along with the concentrators.

While there are many low cost and easily accessible energy sources available in the market why should you go for solar power? This is what most of us think in the first place. But to our surprise this natural energy source can benefit us beyond imagination. As a solar energy user you will be benefitted in three different ways.

1. Renewable: Being renewable source of energy, you can use it at your will. You do not have to worry about the long power cuts or depend on the utility companies. Once you have the solar panels set, you are free from the conventional energy resources. Uninterrupted cooling and heating, continuous power supply and complete security are few of the benefits of solar energy.

2. Environment friendly: Home owners and entrepreneurs who are in favor of protecting environment and preserving the natural resources go for solar power as the first choice (Global warming is a major threat posed by the world). It is widely believed that use of fossil fuels contributes towards the increasing level of pollution. They are being exploited at a great speed. In this rate after a few decades there will be no tree or no pure water source left. In other words solar energy is capable of preventing the premature end of the planet.

3. Cost-effective: Solar energy allows you to cut down your electricity bills and utility charges. You do not have to worry about the cost incurred in maintaining a battery or power back up. All you have to spend is for one time installation of the panel and stay tension free for the next 20-25 years. Though there is no specific shelf life for the solar cells they last for quite a few decades if used properly.

If the cost seems to exceed your budget, you can go for funding assistance offered by your government.
There are other benefits of using a solar panel. You can adjust the direction of the panel as per the direction of the sun. The panel can be removed and installed anywhere, especially on the roofs where sunlight is found in abundance. You can have pleasant winters and cool summers with effective and uninterrupted heating and cooling systems that work on solar energy.

With the entire benefits one would not think twice to opt for solar power over the conventional fossil energy. By cutting down on pollution and wastage of natural resources you can certainly become a responsible citizen.