What is Solar Cell Technology and why it has a Bright Future?
Solar Energy has a bright future following the discovery of Perovskite-made cells.
The world is trying to shift to renewable forms of energy following the pollution caused by the combustion of fossil fuels. Solar energy is probably the most feasible solution for the ever-increasing energy requirements of the world. The solar cell is an electrical device that uses photovoltaic effect to directly convert light into electricity. The electrical characteristics of these cells are dependent on light as they belong to a class of photoelectric cells. A regular solar cell has the ability to produce a maximum open-circuit voltage of 0.6 volts. These cells are grouped together in order to enhance their capabilities. This gives birth to a thing called solar panel. The working mechanism of this environment-friendly cell is explained below.
Silicon is a vital part of a solar cell as it is a semiconductor and shares the properties of conductors and insulators. Light is made up of small packets of energy which are known as photons. They strike with the loose electrons of silicon atoms to pass their energy to them. When this happens on the scale of a solar panel, a pool of lose electrons is formed. The next thing that a solar cell needs to do is to create an electrical imbalance so that these electrons should move in a single direction. Once this happens, electricity is generated. The manufacturing of the cell has a massive role to play in this regard.
A tightly packed structure of silicon atoms is created by inserting small quantities of other elements. This leads to the formation of two different types of silicon, n-type and p-type. P-type silicon has holes (shortage of electrons) in it while n-type possesses spare electrons. Both these materials are placed together inside a solar cell. This results in the movement of electrons from the n-type silicon, making it negatively charged, to the p-type silicon, which becomes positively charged. Ultimately, an electric field is generated across the cell. The insulator side of silicon maintains this imbalance and the electric current produced can power everything from a calculator to a satellite.
Solar energy faced quite a lot of criticism for being expensive and inefficient but latest statistics have revealed how it does more good than harm. It is not only environment-friendly but offers long-term financial benefits as well. Continuous improvement in the technology following the increase in demand has played an instrumental role in cutting down the cost. You might have to spend a substantial amount of money as a startup cost but the drop in electricity bills will cover that up pretty quickly. The supply of non-renewable resources is limited and it is depleting at a rapid rate. Sunlight is readily available and it will stay that way as long as we have the sun. Last but not the least, solar energy is much safer for humans as the burning of fossil fuels contaminate the air we breathe.
Considering the benefits associated with solar energy, scientists are working very hard on improving the quality of solar cells. The most important challenges they face are cost, efficiency, and stability. Recent reports suggest that an all inorganic perovskite solar cell could be the solution they were after. True perovskite is a mineral that is made up of a specific arrangement of titanium, oxygen, and calcium molecules. The structures having similar chemical composition are known as Perovskite Structures. They are pretty good at absorbing light and that’s the reason why scientists want to produce solar cells from this material.
Despite the potential of revolutionizing the solar cell industry, perovskite structures have a severe drawback which hinders their expansion at commercial scale. They are extremely unstable and can deteriorate when exposed to heat. Professor Yabing Qi and his team have developed a device from a new perovskite material that is stable, cheap, and efficient. Heat stability is crucial for solar cells as they can get extremely hot in the sun. Considering this fact, the Energy Materials and Surface Sciences Unit at the Okinawa Institute of Science and Technology (OIST) used only inorganic components for these new devices as organic substances are not thermostable. Dr. Zonghao Liu, an author of the study, told the world about that in the following words:
“The solar cells are almost unchanged after exposure to light for 300 hours.”
Qi and his team are working hard to make these new cells durable and efficient for commercial use.
Computer Scientist by qualification who loves to read, write, eat, and travel