General Lighting Future of technology LED

DOE’s LED Report Highlights A Missed Opportunity

The US Department of Energy has recently released an update to its 2013 report “Adaptation of LEDs in Common Lighting Applications,” which apprises the scientific community on some of the developments in the applications discussed in the original report. The original report focused on the adoption of LED technology in 10 common applications for general lighting, as well as the projected savings for full market penetration of LEDs.

A More Efficient State of Being

The Department of Energy’s updated LED report states that the US would have saved up to 4896 trillion BTUs (tBTUs) of energy in 2014 if 10 out of 10 of these common applications had been converted from traditional lighting to SSL-based lighting. At 3% total penetration by LED lighting, the US was able to save 143 tBTUs, which translates to a total of $1.4 billion in saved energy costs. Compared to 71 tBTUs ($675 Million) saved in 2013, the trend is certainly a positive one. Most of these conversions were A-lamps, which do not offer the same energy saving opportunities as other forms of lighting. In response to these findings, the DOE has announced opportunities for funding into research on substituting SSL-based lighting in situations that would greatly increase the amount of energy saved per year.

Some of the most compelling data is in commercial applications for lighting, which typically use high/low bay and linear fixtures. These applications have not reached anywhere near their potential, currently at only 1.3% for linear fixtures and 2.2% for high/low-bay fixtures. The long hours and high lumen output requirements for these fixtures, if converted to SSL lighting, would represent a significant portion of the available energy savings in the US. If every commercial venue converted 100% of its lighting to LED, the DOE states the immediate energy savings would be up to 1165 tBTUs.

Elektrostandard LED light bulb- Anton Fomkin


The Only Way Forward

The price of LED lighting continues to decrease as developments in technology reduce production costs. Developments in smart lighting technology will also put LEDs in a favorable position on the market. As LED CRI improves to be more human friendly, and the initial price of conversion continues to go down, it has been predicted the DOE will be able report a steady increase in the number of BTUs the US saves each year. In some cases, linear fluorescent lighting with state-of-the-art ballasts remain the most frugal competition, but cannot compare with LED lamps and fixtures in long term ROI.

The DOE plans to provide researching funding opportunities in the Small Business Innovation Research and Small Business Technology Transfer programs. A webinar was held on the July 30th to review the applications for LED and OLED projects. A second webinar is scheduled for August 21st.


General Lighting LED

Good News for the Environment: Americans Have Embraced LED

Osram Sylvania has released their seventh annual socket survey and I, Dr. Bulb, believe the results are encouraging. It seems that the speedy development of LED technology has helped raise it to the top of the lighting market. Osram’s report shows that 78% of Americans surveyed have made the switch from incandescent to LED.

LED lighting has, since its inception, made a slow but steady climb to the top of the lighting market. At first, the high cost of production made LEDs more expensive than most people could afford. Despite the long term savings, many were not willing to make the initial investment. For a time it was the compact fluorescent (CFL) bulb which held dominance over the energy efficient lighting market. However, for both the LED and the CFL, the bright blue-white light was an off-putting factor that sent many traditionalists running for the incandescent bulbs.

Now, advancements in LED technology have reduced the initial price point with more efficient materials that are easier to produce and better CRI that is friendlier to the human eye. As the “human centric lighting” movement gathers speed, LED products are currently in production that are able to change their color temperature to suit the consumer’s needs. LEDs have gained ground in other aspects of technology as well. Recent developments in Visual Light Communication (VLC) have made incredible smart lighting technologies possible.

The Osram Socket Survey indicates that 62% of Americans are aware of innovations in smart lighting, though only 10% have actually purchased smart bulbs for their homes. Although the latter number is small right now, Osram’s findings indicate the the smart lighting trend will continue to grow: 83% of Americans surveyed believe smart lighting is a great start to home automation with 72% believing that smart lighting will soon replace all traditional lighting technologies.
The outlook for the future of energy efficiency is, pardon the pun, very well lit. The majority of the consumers surveyed who use LED bulbs belong to the Millennial generation, demonstrating in clear numerical facts that the ‘kids these days’ are doing their part to help the environment. The continued trend in LED adoption and development of home automation via smart lighting innovations could be a turning point in the way the US uses energy.

General Lighting LED

GaN on Silicon: A New Era for LEDs

LED lighting offers an increasing number of benefits for people who choose to make the switch from incandescent. Progress in LED performance continues to develop at a phenomenal rate, with the average LED efficiency currently sitting at 50%. Some laboratory tests have produced LEDs with an efficiency as high as 60% and it is expected the number will continue to rise. With such productive energy use and an extensive operating life, LEDs are taking over the market for lighting. The one gating issue to the seemingly inevitable success of the light emitting diode is the cost to produce them.

Scientists are seeking to solve the issue by developing a method of producing LEDs which will utilize more affordable materials. In the early 1990s, japanese researcher Shuji Nakamura developed a method of growing thin gallium-nitride (GaN) layers on sapphire substrates to produce high-brightness blue LEDs. As you might imagine, sapphire is an expensive substrate material and certainly adds to the cost of LED production.

A strong candidate for the replacement of sapphire is silicon. Although the material is much more common and more cost effective, there are still some obstacles to overcome. Semiconductors are characterized by the amount of space between the atoms in the crystal lattice. For optimal results, the substrate atoms should be spaced at the same distance as the atoms in the GaN layer. The mismatch causes strain which in turn causes sporadic dislocations of atoms. As a result, electrical current can leak and the LED performance is impaired.

Researchers have already begun working on several solutions to the problem. A mirror on the surface of the LED replaces the substrate after it is used to grow the GaN layer. The structure of the LED is flipped and the light is generated upwards. In addition, the high refractive index of GaN creates a narrow cone through which light can escape. By roughening the surface, scientists have been able to remove the total internal reflection (TIR) restriction. Further enhancements to light output can be made with the addition of a lens.

It is expected that, as research continues over the next few months, that GaN-on-Si LEDs will match the performance of GaN-on-Sapphire LEDs. The use of silicon as a substrate will accelerate the market for LED lighting. With the ability to reduce LED production cost while also cutting energy consumption, homeowners, property owners and other consumers are likely to save hundreds of dollars annually on their lighting related expenses.