08-10-2016, 03:49 PM
1458472267-pptofplastic2.pptx (Size: 451.67 KB / Downloads: 5)
Introduction
Solar cells are designed to convert light to electrical energy
The demand for resources that are everlasting and ecofriendly is increasing day by day.
The working of plastic solar cells is same as that of conventional solar cells but these solar cells are of small size and harness all the rays from the sun’s radiation
Because of their small size and light weight, they exhibit unusual and interesting properties governed by quantum mechanics
Nanotechnology is used in plastic solar cells
What is nanotechnology?
Nanotechnolgy is often referred as general purpose technology
It offers better built, longer lasting, cleaner, safer and smarter products for the home, for medicine, and for industries for ages.
These properties of nanotechnology have been made use of in solar cells.
Nanotechnolgy comprises a wide variety of disciplines: chemistry, physics, material science, molecular biology and computer science.
conventional solar cell
The most common type of solar cells are photovoltaic cells
Converts sunlight directly into electricity
Cells are made of a semiconductor material (eg, silicon)
Light strikes the photovoltaic cell, and a certain portion is absorbed
The light energy(in the form of photons) knocks electrons loose, allowing them to flow freely, forming a current
Metal contacts on the top and bottom of PV cell draws off the current to use externally as power
Infrared plastic solar cell
Scientists have invented a plastic solar cell that can turns the suns power into electric energy even on a cloudy day.
The plastic material uses nanotechnology and contains the 1st generation solar cells that can harness the sun’s invisible infrared rays.
This breakthrough made us to believe that plastic solar cells could one day become more efficient than the current solar cell.
The researchers combined specially designed nanoparticles called quantum dots with a polymer to make the plastic that can detect the energy in the infrared.
Construction of plastic solar cell
The solar cell created is actually is actually a hybrid, comprised of tiny nanorods dispersed in an organic polymer or plastic
Nanorods are made of cadmium selenide
This layer of around 200 nanometers thickness is sandwiched between electrodes and can produce at present about .7volts
The electrodes are coated with aluminium
Working of plastic solar cell
Nanorods are in the plastic solar cell acts like wires when they absorb light of specific wavelength they generate an electron and electron hole vacancy in the rod that moves around just like an electron
This electron travels the length of rod until it is collected by aluminium electrode
The hole is transferred to the plastic which is known as a hole carrier and conveyed to the electrode creating current
Applications
Development of a super thin disposable solar panel poster
A hydrogen powered car painted with the film could potentially convert energy into electricity to continually recharge the car’s battery
Any chip coated in the material could power cell phone or other wireless devices
Improvements
Some of the better improvements include better light collection and concentration which already are employed in the commercial solar cells
In their first generation solar cells, nanorods are jumbled up in the polymer, leading to the loss of current via electron hole recombination, and thus lower efficiency
They also hope to tune the nanorods to absorb different colors to span the spectrum of sunlight.
Advantages
They are considered to be 30% more efficient when compared to the conventional solar cells
They are more efficient and more in practical application
Traditional solar cells are bulky panels. This is very compact
Flexible, roller processed solar cells have the potential to turn the sun’s power into a clean, green, consistent source of energy
If we could cover .1% of the earth’s surface with the solar farms we could replace all our energy habits with a source of power which is clear and renewable
Limitations
The biggest problem with this is cost effectiveness. But that could change with new material. But chemists have found a way to make cheap plastic solar cells flexible enough to paint onto any surface and potentially able to provide electricity for wearable electronics or other low power devices
Relatively shorter life span when continuously exposed to sunlight
Could possibly require higher maintenance and constant monitoring
Conclusion
Plastic solar cells help in exploiting the infrared radiation from the suns rays
They are more effective when compared to the conventional solar cells
The major advantage they enjoy is that they can work even on cloudy days, which is not possible in the former. They are more compact and less bulkier
Though at present cost is a major drawback, it is bound to be solved in the near future as scientists are working in that direction
As explained earlier, if the solar farms can become reality, it could possibly solve the planets problem of depending too much on the fossil fuels, without a chance of even polluting the environment