Philips Lighting North America has won the US Department of Energy (DOE) Bright Tomorrow Lighting Prize (L Prize) competition in the 60W-replacement-lamp category with its remote-phosphor-based design. The Philips LED-based lamp has undergone 18 months of vigorous lab and field testing including having 1300 lamps installed around North America in real applications and Arun Majumdar, Senior Advisor to the Secretary and Director of Advance Research Projects Agency-Energy (ARPA-E) at the DOE, today pronounced the solid-state-lighting (SSL) lamp the winner.

Philips will collect a $10 million prize for developing a 60W-replacement lamp that meets the stringent L Prize requirements including efficacy in excess of 90 lm/W. Perhaps more important, Philips will enjoy the explicit endorsement of its lamp by the DOE and a long list of L Prize partners that will also offer purchasing promotions and incentives.

The DOE launched the L Prize competition in 2008 to encourage the development of SSL products that can drastically reduce energy usage centric to lighting. The 60W-replacement category was a target for the program because that lamp is the most widely-used incandescent bulb in homes – 50% of the US incandescent market, says the DOE. According to the DOE and Philips, the US would annually save 35 TWh in electricity and $3.9 billion, and reduce greenhouse gas emission by 20 million metric tons if every 60W incandescent bulb was replaced with an LED lamp that meets the L Prize efficiency standard.

“The L Prize challenges the best and brightest minds in the US lighting industry to make the technological leaps forward that can greatly reduce the money we spend to light our homes and businesses each year,” said Energy Secretary Steven Chu. “Not only does the L Prize challenge innovative companies like Philips to make LED technology even more energy efficient, it also spurs the lighting industry to make LEDs affordable for American families.”

“We looked at the L Prize challenge as an opportunity to innovate and develop an energy-efficient alternative to a product that has remained largely unchanged for over a century,” said Zia Eftekhar, CEO of Philips Lighting North America.

60W L Prize requirements

The DOE defined a tough set of requirements for potential contestants including more than 900 lm light output at less than 10W in power consumption. In contrast, typical 60W incandescent lamps output around 700 to 800 lm delivering maximum efficacy in the 13 lm/W range.

Other L Prize requirements include a 25,000 hour rated life, CRI of more than 90, and color temperature between 2700K and 3000K. The actual list of detailed requirements is quite a lot longer, including omnidirectional light distribution and robust thermal performance.

Philips just revealed the actual specifications of its L Prize lamp for the first time after winning the prize. The lamp outputs 910 lm at 9.7W delivering an efficacy of 93.4 lm/W, a CCD of 2727, and a CRI of 93.

L Prize entrants also had to present a manufacturing plan to the DOE that will lead to launch of a commercial product. The L Prize partners have suggested a $22 selling price for the lamp at introduction. At this point Philips hasn't addressed price and is only saying that it hopes to begin selling the lamp in early 2012. The DOE will award the cash prize based on the manufacturing plan as opposed to the actual launch of the product and commercial availability.

A unique lamp look

The Philips design is quite unique in that the LEDs are mounted radially in three optical segments that individually might look like a portion of an incandescent lamp except for the yellowish remote phosphor that’s apparent when the lamps are powered off. Air cooling channels separate the segments.

While Philips hasn’t yet offered the L Prize candidate lamp for sale, it does sell the similarly-designed EnduraLED 800-lm lamp at major retailers. That product was the first 60W-replacement LED lamp to win Energy Star certification.

Philips submitted its L Prize entry in September of 2009 and the evaluation process conducted by the DOE and the L Prize Partners has taken until now for a conclusive judgment. Philips' Eftekhar said, “The fact that we are the first and only company capable of submitting a product and completing 18 months of rigorous testing not only underscores our commitment to innovation and quality, it highlights our ability to bring meaningful leading technologies into the mainstream.”

DOE tests 1300 samples

In July, the DOE provided an update on the L Prize competition including a timeline and details on progression of the Philips lamp through the process. Over the summer and fall of 2010 there were 1300 samples of the Philips lamp installed in more than 40 sites across North America. In March 2011 the DOE concluded 6000-hr long-term testing of 200 lamps for lumen maintenance. And now the DOE has finished the technical review of that data and pronounced a winner.

Ironically, interest in the L Price had recently heated up after Philips had been the only entrant for 18 months. First Lighting Science Group (LSG) announced intention to enter the 60W-replacement competition in March, partnering with Light Prescriptions Innovators. More recently, GE Lighting announced its intention to enter a 60W-replacement lamp that utilizes custom LED components from partner Cree.

The DOE has said that it will continue the L Prize 60W program evaluating up to two additional products in that category. Those products would still be eligible for L Prize Partner promotions if they successfully pass the evaluation process. It’s not clear that either LSG or GE Lighting has submitted the requisite sample lamps required to move their entries forward. Moreover we will wait and see if there is still interest among companies in entering the 60W category given that the cash prize is gone.

L Prize next steps

There are two remaining elements to the L Prize competition. The DOE originally announced a competition focused on SSL replacement for PAR 38 Halogen lamps at the same time that it launched the 60W competition. The DOE put the PAR 38 competition on hold early this year citing the need to revise the program based on what it had learned in the 60W competition.

There had not been an entry in the PAR 38 competition at the time of the suspension. Presumably that PAR 38 competition will be reopened in the near future. The competition requirements document specified a $5 million prize for the PAR 38 winner.

The DOE has also said that it would later add a competition called the 21st Century Lamp category from an SSL product that delivers 150 lm/W. Details of that competition have never been revealed, nor has a date for the start of the competition.