LED and OLED lighting 'needs further refinement' - U.S. DOE

04 Sep 2014

Annual market analysis of SSL sector says it needs more work to cut costs and understand consumer resistance.

The U.S. Department of Energy (DOE) has published the 2014 edition of its Solid-State Lighting Manufacturing R&D Roadmap. The Roadmap, which complements the SSL R&D Multi-Year Program Plan, intended for R&D programs, aims to guide manufacturing R&D planning and help direct funding requests.

The Roadmap is updated annually with industry feedback from a series of roundtables with experts and from attendees at DOE's SSL Manufacturing R&D Workshop, which this year was held in May in San Diego, CA. This year, the Roadmap’s analysis of LED cost drivers has been expanded, as has the discussion of the OLED manufacturing cost model, and a new priority task on OLED panel manufacturing has been added.

Key recommendations for 2014

Recent DOE analysis by Navigant Consulting, reviewing U.S. adoption of SSL technology concluded that annual energy savings from LED-based lighting in 2013 more than doubled from the previous year to 188 trillion BTUs (55.1 billion kWh), equivalent to an annual energy cost savings of about $1.8 billion.

But despite this, market penetration is described as “still quite modest”. For one high-profile form factor, A-lamps, it was estimated that only about one percent of the installed base is LED lamps, although growth is accelerating rapidly. From 2012 to 2013, the U.S. installed base of LEDs in general lighting applications more than doubled to about 105 million units.

Navigant further concluded that the energy savings represents only a tiny fraction of the total potential energy savings of about 4.1 quadrillion BTU (1.2 trillion kWh) assuming complete adoption of SSL. The report stated, “While widespread adoption may be several years off, the potential highlights the importance of developing a robust, high-capacity manufacturing capability for SSL. Market adoption is likely to accelerate as prices continue to fall and unit sales are expected to increase at a much faster rate than revenues.”

In response to this energy-saving opportunity, the DOE SSL manufacturing initiative was launched in 2009 to support reductions in SSL manufacturing cost, improve product quality and consistency, and establish a strong SSL manufacturing base in the U.S. The DOE SSL manufacturing initiative has so far supported almost $100 million in manufacturing R&D projects directed at identified priorities.

Current projects include Cree’s development of lower-cost integrated LED luminaires, Philips Lumileds’ development of patterned sapphire substrate technology for lighting caliber LEDs, and OLEDWorks’ development of OLED deposition technology for lighting products. DOE-supported SSL manufacturing R&D projects now cover much of the value chain of SSL production.

R&D / funding priorities

To identify priority tasks appropriate for funding, DOE engaged the LED community beginning with a "round-table" meeting to review the state of LED-SSL manufacturing technology. The meeting took place in Washington, DC in February, followed by the annual SSL Manufacturing R&D Workshop, in May in San Diego. R&D priorities and other conclusions are summarized here:

• For LED and OLED-based lighting products, long-term color stability is still poorly understood and mitigation approaches add to the cost of LED lighting products. The ability to understand and predict color shift over time would increase consumer confidence and cut costs.

• Luminaire manufacturing continues to change significantly in response to the new technology, with less emphasis on the lamp-fixture paradigm and increasing emphasis on integrated luminaires.

• Highly flexible luminaire and module manufacturing will be needed to address the rapidly expanding market.

• More attention needs to be paid to the manufacturing of phosphors/down-converters and the efficient application of these materials within the LED package.

• There is an opportunity for the domestic OLED community to work together to create a viable U.S. manufacturing infrastructure for OLED lighting products and promote consumer acceptance of OLED lighting products.

• The OLED community is preparing to introduce products for lighting by working to understand the needs of luminaire and lighting designers – and to better understand market barriers to LED adoption.

• For OLEDs, solution and vapor deposition approaches are both being explored and hybrid approaches are common. Though commercial OLED panels are mostly based on vapor deposition techniques, major efforts are underway to promote solution processed panel production.

Overall, the DOE Report concludes that “the primary challenge for LED lighting is to ramp up production and continue to drive down costs, while maintaining product quality and consistency. The emerging challenge is to demonstrate to the customer the added value offered by LED technology, whether it is reduced energy consumption, extended lifetime, or added functionality, and to avoid customer disappointments.

“The expansion of LED lighting manufacturing capacity will, in the short term, require the refinement of existing manufacturing approaches. Longer term, it will require the introduction of innovative approaches to lighting product design and manufacturing.”>/p>

”The biggest challenge for OLEDs is to develop acceptable, cost-effective manufacturing processes and build demand by identifying lighting applications that play to the strengths of OLED technology. OLEDs need to translate some recent successes in efficacy and other performance parameters into cost-effective manufacturing.”

About the Author

Matthew Peach is a contributing editor tooptics.org.