Graphene-coated solar panels are designed to absorb sun rays and convert them into electricity. Sun, being the ultimate source of life, is also the ultimate source of energy. The energy that it provides is more than enough to meet the demands of the whole world. Lack of advanced knowledge, innovations and technical breakthroughs in this field has caused this vast and omnipresent reserve to remain underutilized.
Research and development, though, has always been in full swing and whatever energy we are presently able to tap is only because of the breakthroughs made by our dedicated researchers from all over the world. From identifying the potential to creating electricity, solar power energy has made great headways in the last few decades.
How do Solar Panels work?
Solar panels are made of solar cells or photovoltaic cells. At present, about 80% of the cells are made of crystalline silicon. The rest of the 20% are made from Cadmium Telluride. When the sun rays fall on the panel, the cells in the panel generate an electrical charge which is directed to the respective channels for use.
Dozens of PV cells are packed together into solar modules which are in turn placed in solar panels that are installed on the roof tops or on open field.
What are Graphene-coated solar panels?
Solar panels made of solar cells which are coated with thin film of graphene are called graphene-coated solar panels.
What is graphene?
In a layman’s language, Graphene is the building block of graphite which is used in pencils as leads. Research has shown and proved that graphene has remarkable properties which when used can attain striking benefits.
According to Wikipedia, ‘Graphene is an allotrope of carbon in the form of a two dimensional, atomic scale, hexagonal lattice in which one atom forms each vertex. It is the basic structural element of other allotropes, including graphite, charcoal, carbon nanotubes and fullerenes.’
Graphene is believed to be 200 times stronger than steel, is nearly transparent and a good conductor of heat and electricity.
Graphene is primarily made of carbon which is in abundance making it relatively cheaper. So products made from graphene are cheap and strong. It has endless possibilities which when explored has redefined the products we currently use and is creating some great ones.
By 2012 the global market for graphene reached $9 million because of its extensive use in semiconductors, battery, composites and electronic devices.
Solar panels are highly effective in absorbing the heat energy and converting it into electricity. Problem arises when there is not much heat to absorb- i.e. at night or when the weather is cloudy. Sun does not shine all the year through. For some brief period there are clouds and rains which block the heat rays from falling on the earth. It is in those days that normal solar panels become least efficient.
Scientists have come up with new discoveries which can overcome such problems. They have identified the ‘wonder properties’ of graphite which could be used to redefine electricity generated through solar panels. The new graphene-coated solar panels helps in creating electricity using rain drops.
A team of four Chinese scientists from Yunnan University and the Ocean University of China have discovered how the application of graphene to solar panels could turn rain into pure energy. Cloud and rain diminishes the efficiency of solar cells in places that are more overcast than sunny.
What if rain could generate power in solar cells? That is the question which the Chinese scientists chose to solve and graphene is their answer. The process of creating a thin layer of carbon from graphite was discovered about a decade ago by researchers at The University of Manchester, who subsequently won the Nobel Prize in Physics for their discovery.
The Chinese scientists placed a thin layer of graphene on top of solar cells which reacted differently with rain water. Rain water contains lots of salt such as ammonium, calcium and sodium. When the positively charged ions of these salts interacted with graphene electrons, electricity was produced.
This thin material has oodles of potential and is basically changing our lives. It is being used in various products as well, such as water purifier, wearable technologies etc. Touted as ‘the world’s most conducive material,’ the application of graphene in solar panels has made them highly efficient.
How do graphene – coated solar panels work?
When creating electricity from sunlight, the graphene coated solar panels work in as much as the same way as the traditional panels that are laid out on roof tops in many homes and work places does. But when the sun hides behind the clouds and it is raining, it is then that the graphene coated cells in the panel becomes active. Graphene separates the ammonium, calcium and sodium ions in the rain from the water. These ions stick to the electrons in graphene creating a dual layer pseudo- capacitor system which generates electricity.
When rain water falls on the solar panels that are coated with graphene, graphene which already is a reservoir of electrons attracts the positively charged ions to it. It is the salt in the rain water and not the water molecules that initiates the process. The mineral salts in the water segregates into positive and negative charged ions. The positively charged ions get attracted to graphene so water molecules stick to graphene and form a layer. The water layer and the graphene layer interact with each other to facilitate the formation of electricity. It is the positively charged ions that interact with graphene to produce electricity.
When there is sun light than the photovoltaic cells become active and create electricity through dye sensitization which is just like the process of photosynthesis in plants.
Upcoming Research on graphene-coated solar panel:
Researchers at the Massachusetts Institute of Technology (MIT) have developed cells which are flexible and transparent and which can be mounted on myriad surfaces such as glass, plastic, paper, tape etc. The power conversion efficiency of the graphene-coated cells are said to vary from 2.8% to 4.1%.
Researchers from AMBER at Trinity College Dublin and scientists from TU delft, Netherlands have created transistors that are made of graphene layered materials. The team is hopeful of printing a wide range of electronic devices from solar cells to LEDs all at cheaper prices.
The team used standard printing techniques to join graphene flakes as the electrodes with other materials which were layered.
Researchers at the Australian RMIT drawing inspiration from the fern plants have come up with an electrode prototype which could boost the capacity of solar power. The graphene based prototype also facilitates a whole new opening in the development of flexible thin film which could capture and store solar power and create a multitude of uses in the field of smart phones, laptops, cars etc.
Researchers at the University of Glasgow have developed solar powered skin made with graphene for robotic hands. This research could create waves in the designing and production of prosthetic limbs or sensitive robots.
Graphene-coated solar panels to be the panels of the future:
‘Solar panels of the future’- that is how promising graphene-coated panels are. They are likely to replace the existing panels and create a whole new demand for the graphene-coated ones. Graphene-coated panels are referred to as ‘all weather panel.’
There are a number of reasons why they are called this:
1. All weather panel:
About 40% of America’s energy can be generated from solar power. But there are a few constraints. The weather being one! States that receive less sunlight or witness rainfall for major part of the year are under a drawback. The existing solar panels do not work efficiently when there is rain as they are primarily designed for high sun heat receiving locations. During rainfall, the existing solar panels produce less or no electricity causing home owners to maintain the traditional system of electricity too for such seasons. This deters many home owners from going solar.
Graphene-coated solar panels provide electricity when sunny or cloudy. This feature alone would boost the sale of the advanced solar power systems in the country.
2. Low cost
Graphene is a very low cost material. Considering the host of benefits it offers, it is hard to believe that graphene comes cheap. The thin layers formed by graphene and placed over solar cells are cost efficient. So the overall cost of the panels will reduce remarkably, thereby, reducing the cost of solar power systems in the market and making them more pocket-friendly.
3. Energy independence
The existing consumers are installing solar panels on their roof or work place and keeping the traditional meter system also because of inconvenience faced during the monsoons. Graphene-coated panels will solve their problem altogether giving them energy independence.
Unraveling the potential of graphene has clearly been one of the major discoveries of the century. Scientists will only take it forward from here. The only way to go is up. You can replace your solar panels with the graphene-coated models today. They are more effective and efficient at a cheaper price. If we are to preserve our earth, then we all have to take small steps. Harnessing solar power is one way to go about it.