May 2011 - Illuminating Engineering Society

NEWS + NOTES
Numbers
Game
131
Temperature (in deg F)
that 4,750 new high-bay
luminaires were required
to withstand to be qualified
for installation in the
Qatar National Convention
Centre
33
Percent of electrical
contractors surveyed by
Electrical Contractor magazine
who believe LEDs are
ready to replace incandescent
lamps
GaN-on-Silicon LEDs:
Hype or Hope?
More than two years ago, LEDs Magazine editor Tim
Whitaker warned against buying into the hype surrounding
Cambridge University’s research on gallium-nitride
(GaN)-on-silicon LEDs. Whitaker cautioned that the process
of growing GaN on silicon—which could significantly
reduce the manufacturing costs of developing LED epitaxial
wafers from sapphire or silicon carbide substrates—
was yet untested and didn’t take into account “things like
uniformity, reproducibility and yield.”
Hoping to disprove claims like Whitaker’s, LED technology
company Bridgelux has developed what it calls
“industry’s first commercial grade performance for a
silicon-based LED.” The technology uses a single 1.5mm,
4,730K power LED operated at 350mA to produce 135
lumens per watt. Bridgelux intends to release products
using the new technology in the next two to three years.
34
Terawatt-hours LED
replacements for the 425
million 60-W incandescent
bulbs sold each year could
save in electricity per year,
according to the DOE
409
Number of decorative
post-top streetlights that
Topeka, KS, will convert to
LED lighting
1,700,000
Kilowatt hours that Dallas
expects to save annually
by upgrading to LED lowbay
fixtures at five downtown
parking garages
Brazilian Beacon
When President Obama and his family visited Rio de Janeiro’s
Christ the Redeemer statue on their Brazilian tour, they had the
opportunity to see it as few had before. Several weeks prior,
the monument had been re-lighted in honor of its 80 th anniversary.
Lighting designer Peter Gasper illuminated the statue with
300 individually addressable, high-output LED projectors from
OSRAM that bathe it in color-changing light.
www.ies.org LD+A | May 2011 27