Industry News




 

04/30/2012

LED Efficiency Droop

 
More efficient LED lighting options may be on the way for building owners and facility managers.

This is a schematic of the transparent LED packaging design (left) and a working blue LED using the design (right). Credit: Yuji Zhao, University of California Santa Barbara

As many facility managers and building owners are aware, LEDs seem to reach a point where more electricity no longer imparts the same kick and productivity levels-off.  But there may be some very interesting developments on the way that will lead toward more affordable and efficient LED options.  Researchers from California and Japan have devised a new design for green and blue LEDs that avoid much of this LED efficiency droop.

By changing the orientation of the crystal structure in semiconductor films, the team created LEDs with high efficiency and extremely low droop. Droop, which is a dramatic drop in efficiency at high currents, is one of the main problems limiting the growth of the solid-state lighting market.

Blue and green LEDs provide the essential hues that blend with other wavelengths to give us the familiar white light we expect from household bulbs. These highly prized colors, however, have been among the hardest to engineer and the "droopiest" of the LEDs.

"We believe this technology could be a big breakthrough and has the potential to change the future of lighting," says Yuji Zhao, a graduate student at the Solid State Lighting and Energy Center at the University of California Santa Barbara (UCSB) and one of the lead researchers on the team.

LED chips are made from layers of doped semiconductors sandwiched together. When a voltage is applied across the layers, electrons and holes (an absence of electrons) migrate toward an area of the LED called the active layer, where they combine, begetting a photon in the process. In most commercially available blue LEDs, the crystals that make up the semiconductor layers are grown in a flat orientation called the c-plane. This traditional orientation of the crystals, however, may create electrical fields that interfere with the reunion of the electrons and holes.

The UCSB researchers' LEDs have non-traditional, tilted crystal orientations that lessen the effect of the field, and exhibit some of the lowest reported measures of droop. Using this approach the team was also able to fabricate LED chips that are smaller than standard commercial LEDs, which could cut down on manufacturing costs.

 


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Visit our website today to learn about the design flexibility of a Morton building and the endless possibilities of partnering with our designBUILD team.


Wood construction is both cost and energy efficient. Check out Morton Buildings and our designBUILD team online today to discover all the benefits of post-frame construction.


When choosing a metal-clad building for your next construction project, consider Morton Buildings, Inc., and their designBUILD team, we’ll make your dream a reality.

We Can Help You Reduce Energy by 30%

Our mission is to help our customers manage their buildings' energy costs, improve reliability, and enhance performance while having a positive impact on the environment.
CLICK HERE to find out how.

 

Add highly responsive multi-zone comfort to any building project, in any climate. Our CITY MULTI H2i R2- and Y-Series VRF systems give you flexibility to fit the needs of any building. Enjoy 100% heating capacity at 0°F outdoor ambient, and 85% heating capacity at -13°F outdoor ambient.  For more information, log on to www.mitsubishipro.com


Tennant Company is a recognized leader in designing, manufacturing and marketing solutions that help create a cleaner, safer, healthier world. With thousands of satisfied customers already using award winning ec-H2O technology, why not see what you're missing? Test ec-H2O on your soils in your facility. Get a free demo.


Tennant Company is a recognized leader in designing, manufacturing and marketing solutions that help create a cleaner, safer, healthier world. With thousands of satisfied customers already using award winning ec-H2O technology, why not see what you're missing? Test ec-H2O on your soils in your facility. Get a free demo.

 

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10/21/2014

U.S. photovoltaic costs continue to decline.

10/20/2014

The EPA looks to help improve energy and air quality during educational facility renovations. 

10/17/2014

Agency says current regulations "don't protect worker health".

10/16/2014

Scientists have developed LED bulbs free of rare earth metals.

10/15/2014

Survey shows a decrease in employees coming to work sick.

10/14/2014

New efficiency ratings available for apartment units

10/10/2014

New code to increase commercial building efficiency.

10/09/2014

Take charge of your electricity bill with these quick tips.

10/08/2014

Illumination improvements take the top award for physics

10/07/2014

Study shows equipment improvements could boost efficiency. 

10/06/2014

New device integrates batteries into solar cell design.

10/03/2014

The switch to green products comes to healthcare facilities.

10/01/2014

Photovoltaic installations serve nearly 2.7 million students

09/30/2014

Incidence of fires and property loss down from 2012

09/29/2014

Academic achievement tied to responsible reporting habits

09/26/2014

Survey shows people more careful, less satisfied in public washrooms.

09/25/2014

A new study shows that switching natural gas for coal will not significantly reduce the amount of CO2 emissions being produced. 

09/24/2014

A new study shows the carbon emission reduction policies individual states have adopted are yielding results.

09/23/2014

A recent survey of industry professionals indicates that investment in energy efficiency projects will increase over the next year.

09/22/2014

Fort Carson in Colorado is well on its way to reaching the goal of net-zero energy by 2020. 

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