Philips’ L Prize Winning Lamp Completes 40,000 Hours of Testing

When the L Prize in the 60W replacement lamp category was awarded in August 2011, samples of the winning product had already survived more than 8,000 hours of accelerated long-term testing. A selection of 31 of those lamps passed the 40,000-hour point of continuous operation last month.

Results show that well-designed LED integral lamps can operate very reliably over long periods of time, with excellent lumen and chromaticity maintenance. The average lumen maintenance for the 31 lamps after 40,890 hours was 95.6%, with no failures. At that rate it would take an average of 194,765 hours of operation for the lamps to reach 70% lumen maintenance (L70), if no other failure modes came into play before then. The average chromaticity change (?Δu’v’) of the 31 lamps after 40,890 hours of operation was 0.00093 – a minuscule difference indicating that there was no detectable colour shift, and that the light emitted today is indistinguishable from the light emitted four years ago.

Sponsored by the U.S. Department of Energy, the L Prize is the first government-sponsored technology competition designed to spur lighting manufacturers to develop high-quality, high-efficiency solid-state lighting products that set leading-edge performance benchmarks for industry.