Many of us have heard the word LED thrown around, but what exactly does it mean? Light emitting diodes, better known as LEDs, are semiconductor devices that produce light very efficiently by passing an electrical current through semiconductor material, which illuminates the LED. Today, LED technology is used in diverse applications ranging from screen displays, interior lighting, traffic signals, advertising and automotive headlamps. LEDs have numerous advantages over incandescent light sources including lower energy consumption, longer lifetime, smaller size, and less pollution to the environment.
Unlike incandescent lamp bulbs, which burn out relatively quickly, LEDs are extremely reliable and virtually last forever since they don’t have a filament and don’t get especially hot. They’re tiny, relatively inexpensive, and easy to control electronically, which equates to huge energy savings over time.
Also, unlike fluorescent lights which contain mercury, LEDs have no toxic elements. When disposing of fluorescent lights, disposal must be arranged through a registered waste carrier. Switching to LEDs avoids the cost and time spent during disposal and reduces pollution.
Lighting our homes accounts for 25% of electricity bills. Choosing LED lights brings electricity bills down because LED lights are up to 80% more efficient than traditional lighting such as fluorescent and incandescent lights. With LEDS, 80% of the energy is converted to light and only 20% comes off as heat whereas with incandescent bulbs, 95% of energy is wasted as heat with only 5% converted to light.
The incandescent light bulb has been around since the late 1800s, but on January 1st, 2014, in keeping with a law passed by Congress in 2007, the outdated light bulbs can no longer be manufactured in the U.S. since they don’t meet federal energy-efficiency standards. Countries around the world are phasing out the incandescent bulb due to higher energy standards and breakthroughs in lighting such as those happening at UCSB’s Solid State Lighting & Energy Electronics Center.
Shedding Light on the Developing World
At SSLEEC, researchers and inventors are addressing pressing problems to find innovative solutions for a brighter world.
Founded in 2007, UCSB’s SSLEEC is a collaborative center that brings key industry leaders and UCSB researchers together. The goal: to advance solid-state lighting and energy efficient power switching using wide-bandgap semiconductors.
What does this all mean? SSLEEC is focused on new semiconductor based technologies for energy efficient lighting, power electronics, and bulk growth of Gallium Nitride (GaN). The objective of SSLEEC is to provide a forum for its members to work in collaboration and across scientific disciplines to address the most challenging problems in these important areas of research.
Researchers at SSLEEC are leading the world in lighting research with new discoveries and inventions. Benefits of this research include discovering more responsible, comfortable, and productive building environments in addition to substantial energy savings.
Shuji Nakamura: Co-Director of UCSB’s SSLEEC & Nobel Prize Winner
Most of the recent advances in solid-state lighting have come from devices based on gallium nitride (GaN) LEDs, a technology that is largely attributed to UCSB materials professor Shuji Nakamura. Nakamura invented the first high-brightness blue LED and his research is revolutionizing lighting technology.
Co-Director of SSLEEC, Professor of Materials, and The Cree Professor in Solid State Lighting and Display, Shuji Nakamura holds many honors and has achieved enormous success in the lighting industry. This past year, he was named the 2015 Global Energy Prize recipient for the invention, commercialization and development of energy-efficient white LED lighting technology. In 2014, he received the Nobel Laureate in Physics for the invention of efficient blue LEDs.
Professor Nakamura is known around the world for his breakthrough with blue LEDs. Creating a blue LED was no small task. In fact, the blue LED was much more difficult to invent than its predecessors. LED technology took decades to develop, beginning with red LEDs in the 1960s, followed by green, orange and yellow. Blue LEDs were the most challenging to invent and the remaining primary color needed to make white LED light. Some thought that it might even be impossible to create a blue LED until Nakamura took on the challenge.
In 1993, Nakamura debuted his blue LED, demonstrating the brightest blue light that had been developed at the time. This innovation led to not only the creation of the white LED, but also the ability to save energy, reduce carbon emissions and provide a low energy, durable and sustainable light source for those with little or no access to electricity. LED technology is helping liberate remote communities from dependence on unhealthy, polluting fuel sources. With this invention, Nakamura has made a tremendous humanitarian contribution to our world.
“LED technology is helping liberate remote communities from dependence on unhealthy, polluting fuel sources. With this invention, Nakamura has made a tremendous humanitarian contribution to our world.”
A Quick Chat with Steven DenBaars: Co-Director of UCSB’s SSLEEC
Alongside Nakamura, Steven DenBaars co-directs UCSB’s SSLEEC. DenBaars is a Professor of Materials and Electrical & Computer Engineering and The Mitsubishi Chemical Professor in Solid State Lighting & Displays. His research focuses on MOCVD growth of wide-bandgap semiconductors (GaN-based) and their application to blue LEDs, laser and high electronic devices. On a day-to-day basis, he supervises graduate students and their research on how to make more energy efficient lighting.
“After two decades of research, LEDs are finally seeing widespread deployment in the house, which is a big deal,” said DenBaars. “But there’s even crazier stuff that we are working on right now. We are now able to make a Wi-Fi network over light bulbs by sending signals over the light, which is called Li-Fi. This allows you to communicate even more information than previously thought possible.” The research happening at SSLEEC is changing the future of lighting and all of its ramifications.
“But one of the most impressive projects being carried out right now is with lasers and laser lighting. Instead of using LEDs, a laser light bulb will take a laser beam and turn it to white light.” These cutting-edge light bulbs will not even need wires to run up to the light bulb and will hopefully provide even greater energy savings than LEDs.
There are so many uses for light. There have been studies in Europe, where under certain LED lighting, elementary students are more productive. In another lighting application, in parking lots where LED lights turn on automatically when people go to their cars, crime rates have dropped drastically. Lighting is also being used in numerous health applications. In Hong Kong, researchers are working on the sterilization of unclean water using ultraviolet LEDs, which could help save hundreds of thousands of lives. DenBaars hopes to see the field of lighting continue to help people be healthier, more productive, and safer.
Future Energy Savings Lie Ahead
Achieving high-quality white light from efficient, affordable, solid-state devices will require extensive multi-disciplinary research and development. If these breakthroughs are achieved, cumulative energy savings between now and 2020 could exceed 14 quads of primary energy – translating to savings of more than $98 billion. Maintaining technology leadership in the United States will yield global market opportunities and high-technology jobs, as well as greater institutional strength in science education and research.
If you are interested in learning more about the research going on at SSLEEC, send an email to firstname.lastname@example.org or check out their website here: http://ssleec.ucsb.edu/
Inspired to bring light to developing parts of the world? Take a look at the Unite to Light project to learn how you can help bring light to regions of the world lacking access to electricity: http://www.unitetolight.org/