Solar Panel Efficiency Break through after a hard work of decades from Engineers and Scientists
In Today’s world renewable energy is the main focus of engineering and energy research for taking the world to the more sustainable era by every country and every group of business. Solar Energy has been a proven cost-effective model for utilizing renewable energy from Mother Nature.
PV panels are new technology, but we need to work out how to make them even more efficient – and scientists just solved a 4-decade old mystery around one of the key obstacles to increased efficiency. A new study outlines a material defect in silicon used to produce solar cells that have previously gone undetected. It could be responsible for the 2 percent efficiency drop that solar PV cells can see in the first hours of use: Light Induced Degradation (LID). Multiplied by the increasing number of panels installed at solar farms around the world, that drop equals a significant cost in GW that non-renewable energy sources have to make up for.
In fact, the estimated loss in efficiency worldwide from Light Induced Degradation (LID) is estimated to equate to more energy than can be generated by the UK’s 15 nuclear power plants. The new discovery could help scientists make up some of that shortfall. “Because of the environmental and financial impact solar panel ‘efficiency degradation’ has been the topic of much scientific and engineering interest in the last four decades,” says one of the researchers, Tony Peaker from the University of Manchester in the UK. “However, despite some of the best minds in the business working on it, the problem has steadfastly resisted resolution until now.”
To find what 250+ research papers across four decades had previously been unable to determine, the latest study used an electrical and optical technique called deep-level transient spectroscopy (DLTS) to find weaknesses in the silicon. Here’s what the DLTS analysis found: As the electronic charge in the solar PV cells gets transformed from sunlight, the flow of electrons gets trapped; in turn, that reduces the level of electrical power that can be produced. This defect lies dormant until the solar panel gets heated, the team found. “We’ve proved the defect exists, it’s now an engineering fix that is needed,” says one of the researchers, Iain Crowe from the University of Manchester. The researchers also found that higher quality silicon had charge carriers (electrons which carry the photon energy) with a longer ‘lifetime’, which backs up the idea that these traps are linked to the efficiency degradation. What’s more, heating the material in the dark, a process often used to remove traps from silicon, seems to reverse the degradation.
The work to push solar PV panel efficiency rates higher continues, with breakthroughs continuing to happen in the lab, and nature offering up plenty of efficiency tips as well. Now that the Light-Induced Degradation mystery has been solved, solar farms across the globe should benefit. “An absolute drop of 2 % in efficiency may not seem like a big deal, but when you consider that these solar panels are now responsible for delivering a large and exponentially growing fraction of the world’s total energy needs, it’s a significant loss of electricity generating capacity,” says Peaker.
Reference Source: The research has been published in the Journal of Applied Physics, other Technologies think tanks and other knowledge-sharing forums.