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FIREFLY LEDS Mr. Rony Joseph S8 EEE The nighttime twinkling of fireflies has inspired scientists to modify a light-emitting diode (LED) so it is more than one and a half times as efficient as the original. Researchers from Belgium, France, and Canada studied the internal structure of firefly lanterns, the organs on the bioluminescent i n s e c t s ’ abdomens that flash to attract m a t e s . T h e scientists identified an u n e x p e c t e d p a t t e r n o f j a g g e d s c a l e s t h a t enhanced the lanterns’ glow, and applied that k n o w l e d g e t o L E D design to create an LED overlayer that mimicked the natural structure. The o v e r l a y e r , w h i c h increased LED light extraction by up to 55 percent, could be easily tailored to existing diode designs to help humans light up the night while using less energy. Fireflies create light through a chemical reaction that takes place in specialized cells called photocytes. The light is emitted through a part of the insect’s exoskeleton called the cuticle. Light travels through the cuticle more slowly than it travels through air, and the mismatch means a proportion of the light is reflected back into the lantern, dimming the glow. The unique surface g e o m e t r y o f s o m e f i r e f l i e s ’ c u t i c l e s , h o w e v e r, c a n h e l p minimize internal reflections, meaning more light escapes to r e a c h t h e e y e s o f potential firefly suitors. Using scanning electron m i c r o s c o p e s , t h e researchers identified s t r u c t u r e s s u c h a s nanoscale ribs and larger, misfit scales, on the fireflies’ cuticles. When the researchers used computer simulations to model how the structures a f f e c t e d l i g h t transmission they found that the sharp edges of the jagged, misfit scales let out the most light. The finding was confirmed experimentally when the researchers observed the e d g e s g l o w i n g t h e brightest when the cuticle was illuminated from below. “The tips of the scales protrude and have a tilted slope, like a factory roof.” The protrusions repeat approximately every 10 micrometers, w i t h a h e i g h t o f a p p r o x i m a t e l y 3 micrometers. “In the beginning we thought smaller nanoscale structures would be most important, but surprisingly in the end we found the structure that was the most effective in improving light extraction was this big-scale structure,” say the researchers. The firefly specimens t h a t s e r v e d a s t h e i n s p i r a t i o n f o r t h e effective new LED coating came from the genus Photuris, which is commonly found in Latin America and the United S t a t e s . “The Photuris fireflies are very effective light emitters, but we are quite sure that there are other species that are even more effective,” says the researchers and will continue to explore the great diversity of the natural world, searching for new sources of k n o w l e d g e a n d inspiration.
THE INTERNET OF ENERGY Mr. KADAVIL SABU HAZEM S8 EEE We waste too much energy and this is a direct cause of global warming. Imagine a f u l l y i n t e g r a t e d electrical system that is s a f e r, c l e a n e r a n d s u s t a i n a b l e . B y utilising the Internet, Smart devices, sensors and switches technologists have designed systems that s a v e e n e r g y i n a n intelligent fashion, saving the consumer money in the process. devices include sensors, Smart devices, lights, motors and vehicles as well as any compatible e l e c t r o n i c s . T h e advantages of such a system are increases in automation, accuracy, efficiency and experience quality; going beyond current “machine: machine” systems. It is estimated that the IOT will contain over 50 billion objects by 2020. The Internet of Energy software and middleware for seamless, secure c o n n e c t i v i t y a n d interoperability achieved b y c o n n e c t i n g t h e Internet with the energy g r i d s . T h e implementation of IoE services involves the use of multiple components, including embedded s y s t e m s , p o w e r electronics or sensors; which are an essential part of the infrastructure d e d i c a t e d t o t h e g e n e r a t i o n a n d distribution energy. The Smart Grid Large territories have developed interconnected electrical supply systems that use the same voltages and currents; these are most evident in large countries/continents like USA, Brazil and the EU where the electrical grids are standardised. The Internet of Things Sometimes the simplest ideas are the best: The Internet of Things uses the existing infrastructure of the Internet to allow devices to communicate and share data. These As a subset of the IOT, the Internet of Energy (IOE) encompasses all objects involved in provision and use of electricity from the power grid down to individual electronic devices. The main objective of the IOE is to d e v e l o p h a r d w a r e , The IOE makes use of millions of sensors across the grid (devices, sockets etc.) and integrated computing systems, connected using existing Internet infrastructure, allowing the prediction o f f u t u r e e n e r g y requirements: The Smart Grid. This affords huge savings in the amount of energy usage, in the form of fossil fuels and others. Encouragingly there are currently over 500 Smart Grid projects
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