May 2011 - Illuminating Engineering Society

ASHFORD ESTATE
Return Visit
When Michael Souter visited the San Francisco’s Intercontinental
Hotel in 2010 to participate in a retrofi t place; however, they have been removed and lab-tested after 3,000,
a satisfaction survey. “In the end, the LED replacements were left in
of some of the hotel’s lighting, he knew whose fi n- 6,000 and 9,000 hours to determine how the lamps have changed in
gerprints were all over the existing design: his own. Souter, design
principal for local fi rm Luminae Souter Associates, did the original
lighting for the Intercontinental in 2008.
Souter’s most recent trip to the hotel was aimed at making some
of that lighting more energy effi cient. “I was
asked to be part of a team to evaluate LED
retrofi t products that could be used,” he says.
“The process involved evaluating the existing
lamp technology and looking for quality
alternatives that would not compromise the
design or guest experience. The candidates
included AR111, PAR30 and MR16 lamps.”
The Department of Energy Gateway project
was a collaboration between Pacifi c Gas &
Electric, Pacifi c Northwest National Labs
(PNNL) and the hotel.
Early on, the team asked various manufacturers
who made LED replacement lamps to
submit samples for testing. “We evaluated
several candidates for color quality, color temperature,
lumen output, color rendition and color temperature,” says Souter.
After each test, the same lamps have been reinstalled. “To date there
have not been any signifi cant changes in performance or quality; the
unexpected surprise is how well the quality of the lighting improved
the wood wall at the reception area.”
Souter, though, is quick to point out
that an all LED approach for hotel lighting
is not yet viable. “Not all light fi xtures are
good candidates for LED replacements.
For instance, in the ballroom the ceilings
were very high and the fi xtures required
100 percent dimming. The available LED
retrofi t products for the existing 150-W
PAR38NSP lamps did not have the required
lumen output, beam spread or full
range dimming ability. At this point, the
best retrofi t applications for the hotel
market are in lower ceiling heights using
PAR30, PAR38 and MR16 halogen lamps,
especially where lighting is on 24/7.
quality of beam pattern, potential
On a personal note, Souter harbors no
The registration desk at the Intercontinental Hotel
flicker and dimming capability,” says Souter. in San Francisco, lighted by incandescent/halogen ill will about some of his original work at
“We took a very quantitative approach during
the evaluation and scored each product accordingly
to the criteria we were looking for.
We selected good alternatives for the PAR30
(above) and LED replacement sources (below).
The designer, who did the original lighting plan,
was pleased with how the LEDs improved the light
quality on the wood wall.
the Intercontinental being revamped. “I’m
not disappointed,” he says. “Actually the
design process started in 2005 and I used
the best technology available at the time.
and MR16 lamps but did not find a good alternative for the AR111.”
The selected lamps were installed in pre-selected testing zones
of the hotel, replacing their incandescent/halogen counterparts for
several weeks to see how they performed. The testing zones included
conference rooms, the registration desk area and elevator lobby,
guestroom corridors and an area where artwork is illuminated.
Meanwhile, to help assess the aesthetic quality of the LED replacements,
hotel staff, management, designers and engineers took part in
Initially I was apprehensive about the retrofi t because of so many
bad LED products on the market and some very bad retrofi ts. The
Intercontinental was also apprehensive that the aesthetics and guest
experience might be compromised. Even after the retrofi t, I am still
consulting with the hotel maintenance staff on how to maintain the
original lighting design. Also, IHG has asked me to consult on several
other hotels with similar opportunities. This is a vote of confidence.”
— Paul Tarricone
www.ies.org LD+A | May 2011 77