Solar power has evolved tremendously since the photovoltaic effect was first observed by Alexandre-Edmond Becquerel in the 19th century. Nowadays, new advances in solar panel technology are introduced every year, as scientists work hard to improve the efficiency of solar cells.
Promising technologies in solar cell manufacturing, solar energy storage, and solar design tech have made solar energy one of the most prominent sources of renewable energy in the world.
The Latest Advances in Solar Cell Technology
Researchers are constantly working on improvements to increase the efficiency and cost-effectiveness of solar cells.
Breakthrough technology announced by researchers at the Massachusetts Institute of Technology (MIT) could dramatically increase the amount of energy solar panels generate. They say, that by capturing and utilizing the waste heat that is emitted by solar panels, a Solar Thermophotovoltaic (STPV) device can be used to improve the efficiency of the panels.
This device contains an intermediate component that absorbs waste heat and emits thermal radiation. By tuning a photovoltaic cell to match the wavelength of this thermal radiation, the efficiency of the panel can be almost double that of a normal photovoltaic (PV) cell. Researchers are now working on the economic scaling of solar thermophotovoltaic devices for commercial use.
Another example is that of researchers at the University of Toronto’s Electrical and Computer Engineering department, who have designed and tested a new class of solar-sensitive nanoparticles. These new solid, stable, light-sensitive particles called Colloidal Quantum Dots could lead to the development of cheaper and more flexible solar cells. The collection of sunlight using colloidal quantum dots depends on two types of semiconductors: n-type, which are electron-rich, and p-type which are electron poor. The problem with n-type materials when exposed to air, is that they tend to bind with oxygen atoms, and lose electrons to become p-type materials.
The work led by post-doctoral researcher Zhijun Ning and Professor Ted Sargent, along with their colleagues, modelled and demonstrated a new colloidal quantum dot n-type material that does not bind with oxygen when exposed to air. This allows the semiconductor to maintain stable n-type and p-type layers simultaneously, which in turn, boosts the efficiency of light absorption. This new quantum-dot-based solar cell architecture can be mixed into inks and painted or printed onto thin, flexible surfaces, such as roofing shingles.
This innovation can dramatically reduce the cost and accessibility of solar power to millions of people.
Perovskite Solar Cells, a breakthrough by the University of Oxford in 2012, have increased conversion efficiency to over 20% in 2019 while still being one of the lowest cost options on the market.
These solar cells convert ultraviolet and visible light into electricity very efficiently, which makes them excellent tandem partners (solar cells optimized to capture light from each section of the spectrum) with absorber materials such as crystalline silicon that efficiently convert lower-energy light into electricity.
The Latest Advances in Solar Energy Storage
Another major focus apart from increased efficiency and lower costs is solar energy storage. At the moment, the electricity that is generated by a solar PV system goes into the grid and must be immediately used, or it is lost. This poses a major problem, as solar energy cannot be generated for 24 hours in a day. Although there are several batteries on the market that store solar energy, they are inefficient and have short shelf-lives. Scientists are constantly trying to explore new ways of storing solar energy.
A new thermal energy storage technique called Molten Salt Energy Storage is gaining popularity all over the world.
The technique uses multiple sun-tracking mirrors called heliostats to reflect and concentrate solar radiation onto a tower-mounted central heat exchanger. Inside the exchanger, molten salt is circulated through tubes that collect the incident solar radiation from the mirrors. The salt is heated using this radiation and the hot molten salt is then routed to an insulated thermal storage tank where the solar energy can be stored for later use with minimal energy losses. When electricity needs to be generated, the hot molten salt is routed to a steam generator which produces steam that then powers a steam turbine. The turbine generates electricity, and the molten salt is routed to a cold salt storage tank. This cycle is repeated throughout the day and night, which makes the availability of electricity constant.
In a project funded by the United States Department of Energy, researchers announced a portable solar energy generator that has built-in battery storage and can provide power anywhere. The main idea is that the generator can provide clean power to everyone, with an option for storage as well. The panels can store both solar and grid power without inefficiencies in transmission and conversion since the storage is placed at the source of the collection itself. By conjoining the battery into the solar panel, researchers were able to lower costs by almost 25% as compared to existing products.
The Latest Advances in Solar Design Technology
With new inventions in solar coming out every year, scientists are slowly exploring several unconventional ways to access solar energy.
Wearable Solar is slowly picking up pace, with the invention of solar textiles that consist of tiny solar panels stitched into the fabric of clothing. This feature will allow for multiple solar applications like heated car seats and heated furniture.
Another useful application that scientists are looking into is solar-powered roadways. The roadways will be lined with solar panels that will be a source for clean solar energy. They will also include a thermal heating option that will keep roads free from snow during winter and LED lights to power street lamps.
Solar irrigation using solar pumps has emerged as a viable, non-polluting source of power for agricultural consumers.
Since solar power is generated during the day, it is ideal for the irrigation of farms even in the case of power cuts. Any surplus power generated can be used by the farmers for lighting or other applications. The excess power can also be sold to DISCOMS at competitive prices providing extra revenue for the farmers.
Overall, solar energy is beginning to establish itself as a prominent clean source of energy that has a varied number of applications. The fact that it is scalable also contributes to its success. Solar energy is sure to play a big role in saving the environment, helping people economically, and creating jobs and research opportunities in the future.