Energy needs have been making headlines all around the world with world governments making efforts to reduce the carbon footprint.
The recent conferences on climate change have also made it clear that the condition of the environment is degrading rapidly and a need for renewable or clean energy has been undoubtedly established.
The best form of clean energy comes from natural resources like wind and water, but the most popular among them is solar energy.
Since solar energy is available around the world, people are more drawn to use them for personal & industrial purposes.
Solar has become one of the cheapest sources of renewable energy while still efficiently providing clean energy around the world.
Solar panels have applications in a wide variety of applications, mostly for domestic purposes.
The solar panels used for domestic purposes can only achieve an efficiency of around 20% of the sunlight.
This efficiency of converting sunlight to pure energy is called solar efficiency.
There are solar panels with higher efficiency of around 40% used in a variety of commercial & industrial purposes.
With the advancement in technology, the effectiveness of the solar panels is increasing day by day, paving the way for cleaner energy.
What Are the Types of Solar Cells
Solar panels consist of silicon cells connected in an array mounted on a rigid metal frame.
When light passes through these solar cells, they set the electron present in them to move this effect is known as a photovoltaic effect.
The frames mostly made from aluminum provide the rigidness required to keep with the harsh environment.
The silicon cells are also encased within a glass sheet to protect it from any environmental damage.
This arrangement is called a solar panel.
The silicon cells are mostly of three types Monocrystalline, Polycrystalline & Thin Film silicon cells.
Monocrystalline solar cells are silicon wafer made in one large single block format.
Solar panels made using Monocrystalline cells are considered more efficient than the polycrystalline & amorphous solar cells.
The monocrystalline solar cell production goes through a more labor-intensive process; hence, they’re more expensive to make.
Monocrystalline panels have a distinct black color, which gives them a premium solar panel look.
Polycrystalline solar cells are also silicon cells that are created by melting multiple silicon cells together.
Polycrystalline solar panels are considered less efficient and less expensive than monocrystalline solar panels.
Polycrystalline cells are made by melting & pouring silicon into square molds.
Polycrystalline solar cells have a blueish color often associated with SolarWorld solar panels.
Thin film silicon cells are made by placing several layers of photovoltaic cells on top of each other to do a single module.
The thin-film silicon cells are one of the cheapest, but they’re also less efficient when compared to their peers.
There are many types of solar cells in the case of thin-film; they differ from each other based on the material used to create it.
The types of thin-film silicon cells are as follows:
· Cadmium telluride silicon cells
· Copper Indium gallium selenide silicon cells
· Amorphous silicon cells
· Organic Photovoltaic cells
How Are Solar Cells Made
Solar cells are formed using silicon dioxide as a raw material, which goes through eight steps to get the required product.
These steps are as given below:
Step One: Silicon Purification
Purification involves heating Silicon dioxide in an electric furnace.
Then to release oxygen, a carbon arc is applied.
This process creates silicon, which has only 1% impurity.
This type of silicon are used for some industrial purposes, but the silicon is still not pure enough for the solar cells.
A silicon rod is with 99% purity is then created to go through the next step.
Now to further purify the silicon, it’s passed through the heated zone several times.
The impurities in the silicon move towards one end of the silicon rod.
After this process, the silicon rod will be considered pure & the impure section of the rod is removed.
Step Two: Single Crystal Silicon
Solar cells are made from silicon boules which are polycrystalline structures that are single crystalline in nature.
These silicon boules can be made using a process called the Czochralski method.
In the Czochralski method, a seed crystal of silicon is dipped into the melted polycrystalline silicon.
Then the seed silicon crystal is withdrawn with rotation creating a cylindrical ingot, which is called boule.
This ingot is 100% pure, any impurities present in the first step is left in the liquid.
Step Three: Silicon Wafers
Silicon wafers are cut from the boule using a circular saw.
Half of the silicon is lost in this process when the silicon is cut into rectangular or hexagonal shapes.
These are shaped as such because they fit together perfectly in the solar panels utilizing all the available space.
The silicon wafers are now polished to remove any marks left due to the cutting process.
Sometimes the manufacturer could leave the rougher ends untouched as its believed to absorb more light to produce more energy.
Step Four: Doping with Impurities
This process involved introducing a small amount of boron during the previous stages.
Another method consists of doping silicon with some phosphorus to shoot the ions into the ingot.
This also involves controlling the speed of the icons to control the depth of sunlight penetration.
The new process is still in the testing phase, though.
Step Five: Placing Electrical Systems
In this process, the individual solar cells arranged in the solar panel are connected through the electrical wiring.
The contact point of these electrical fittings needs to be extremely thin so that they don’t block any sunlight.
Usually, metals like copper are vacuum evaporated or placed in the spaces that are unused by the solar cells.
After the individual solar cell contact is established, thin stripes are placed between the cells, mostly using tin-coated copper.
Step Six: Anti-Reflective Coating
Pure silicon is shiny, which means that 35% of the sunlight reflects.
An anti-reflecting coating is done on the silicon wafers to reduce the loss of the sunlight.
Mostly titanium dioxide or silicon oxide is used for this purpose.
The material either goes through a high voltage to get deposited over silicon wafers or its heated so that the material condenses over the silicon wafers.
Step Seven: Silicon Wafer Protection
Now the almost finished solar panel is sealed into silicon rubber or ethylene-vinyl acetate solution.
The encapsulated solar cells are now placed over an aluminum frame & covered with a transparent glass or plastic sheet.
The finished product is called a solar panel.
Step Eight: Testing Solar Panels
Once the solar panels are ready, testing is performed to check whether solar panels are working as per expectations.
The solar panel is put in a flash tester at the manufacturing facility.
The tester will deliver the equivalent of 1000W/m2 irradiance, 25°C cell temperature, and an air mass of 1.5g.
These test results are compared with the standard industry norms.
The performance parameters are listed on the solar panels & can be found on the user manuals.
The solar panel rating will prove information about power output, efficiency, voltage, current, impact, and environmental tolerance.
The solar panels are also tested in the real world scenario by the manufacturers.
If both the standard testing & real-world testing parameters are found within the operation limited, the solar panels are moved out of manufacturing for shipment to the customers.
Most of the solar panel manufacturers also provide expert installation services so that the panels are set up at the customer’s choice of location to provide maximum benefits.
Since the angle in which solar panels are installed is very important to get maximum sunlight benefits, the manufacturer takes good care of the installation service.
The fixed solar panel installation must be installed by the specialist as calculation of the optimal sunlight is to be made.
If installed by someone other than the manufacturer’s service executives, the manufacturers don’t guarantee the performance of their solar panels.
Everyday Products That Use Solar Panels
Solar Powered Phone charger is some of the best products to use if you’re always traveling.
The best part of being a solar charger is that anytime during a day, you can put your phone on charge using a small solar panel provided with the device.
Solar Powered Lights are very useful for street lights & traffic lights.
They charge themselves during the day & store electrical energy into a battery.
During the night, they use the stored energy to provide street light to travelers.
One more usage is to connect your decorative lights with the solar panels; they will charge themselves during daytime & provide decorative lights during the night.
Solar Powered Irrigation pumps are of widespread use in rural India & the government of India is providing subsidies to the farmers for irrigation pumps.
Solar has reduced the cost of farmers as the overhead of electricity is reduced to null.
Solar Powered Mobile Towers are used by many countries to provide the mobile signal to the less populated regions.
Underdeveloped or Developing nations are using the power of solar to power mobile technology.
Solar Powered Smart Homes are becoming a norm for most modern-day architects.
The goal is to design a self-sustaining smart home that has a limited requirement for outside power.
The idea is to reduce the dependence on the power grid & commit toward green energy.
Rooftop Solar Panels setup is typical in most individual homes & residential societies.
The government encourages & provides subsidies to suburban communities to install rooftop solar plants.
These plants not only reduces the power bill of the city, but it also reduced the load on the national power grid.
Upcoming Technologies for solar Cells
Scientists are exploring the possibility of lining up the highways with solar panels.
These solar panels will provide a considerable amount of clean energy to the electrical grid as the space occupied by the roads in any country is quite large.
Netherlands is already in the process of testing a solar highway project.
Another way to overcome the land usage barrier is to construct a solar grid over water.
The solar canal project in India is already well established & continue to provide electricity to the power grid.
Scientists are trying to harness the energy of the sun from space.
An old technology of space-based satellites capturing energy & beaming them back to Earth is in consideration.
Since satellites are placed in a way to optimize the capture of sunlight, they can be a good source of clean energy.
This technology will capture significantly more amount of energy & beam it back to the Earth in the form of a microwave.
Emerging economies like India & China are investing heavily in these technologies.
The Environmental Benefits of Using Solar
Solar panels create clean, renewable energy which benefits the environment.
Alternative forms of energy are fossil fuels based, which increases the carbon footprint.
Increased usage of solar power has had a tremendous effect on the environment.
Most of the electricity generated in any country comes from fossil fuels.
Fossil fuels are becoming more expensive as they need to be extracted & processed before use.
The solar energy is available free around the world in abundance.
If we could capture all the sunlight on Earth for just 1 hour, it could power the entire world for one year.
Investing in solar energy means investing in the technology of the future, which is abundant, consistent & free.
Solar energy becoming an alternative to fossil fuel-based energy, will drastically reduce the emission of greenhouse gases.
Greenhouse gases are responsible for the rise in global temperature and climate change.
Climate change is the prime contributor to the public health issue, extreme weather, rising sea levels & changing ecosystems.
When we know that the age of fossil fuels is coming to an end, it would be wise to invest in the technology which can power our future.
The drawbacks of solar energy are none, but the advantages are plenty.
The developing countries are serious about the issue of clean energy & the conference on climate change in the united nations has proved that clean energy is the need of the hour.
Solar is the most commonly used clean energy source that will continue to evolve & support the energy needs of the world.