The rapidly rising cost of air conditioning energy is a problem for hospitals everywhere, and McAllen, Texas, is no exception. In a town where over 90˚F days are common yearround,
and the mercury can top the 100˚ mark even in winter, the seasons might be described as “hot and hotter.” But at McAllen’s
Rio Grande Regional Hospital, administrators are staying cool
with the knowledge that — even in the face of a 33 percent utility
rate hike — their electric bill has declined over the past two years.
What accounts for this phenomenon? You might be surprised.
“We attribute it to the incorporation of UVC lights into the
air handling systems,” answered Oscar Molano, director of
plant operations for the hospital. “We were looking for a way
to save on a/c energy costs without compromising air quality
or patient comfort.”
Th ey found the light (UVC), so to speak.
Working with Rio Filter Supply Co. of Harlingen, Texas, Molano fi rst learned that high-output ultraviolet-C band
(UVC) devices have become a popular addition to new and
existing HVAC systems because of their multiple performance
benefi ts. Th e energy emitted by the UVC devices is considered
the most germicidal in the ultraviolet spectrum.
Properly installed in air handlers, high-output UVC lights are
designed to penetrate even the tiniest microbes to destroy their
DNA and RNA, killing or deactivating them. In this manner, the
lights eff ectively degrade mold and other organisms that sometimes
grow deep inside HVAC systems, as well as airborne microbes that
circulate through these systems to the occupied space.
Decades-old studies have shown that even a microscopic
layer of organic buildup on a/c coil fi ns can create a noticeable
drop in system effi ciency. By eliminating this buildup and preventing
its recurrence, UVC devices are designed to keep coils
continuously clean. Th is, in turn, lowers HVAC energy costs by
improving heat transfer and increasing net cooling capacity.
This graph shows the energy savings achieved at Rio Grande Hospital in
2007, as compared to energy consumed in 2006. (Information provided
UVC energy is designed to destroy airborne microbes,
including all types of viruses and bacteria. It can help to
maintain cleaner indoor air and reduce the risk of crossinfection
in health care facilities. Th ough Rio Grande has
not yet studied this aspect of UVC performance, some hospitals
have reported reductions in nosocomial infection rates since
adopting the technology.
UVC also is designed to help control indoor humidity and
comfort levels. It can accomplish this end by keeping air conditioning
components running cleanly and effi ciently and improving
airfl ow through the coils. At Rio Grande, all 26 AHUs are
now running in “as new” condition, said Molano.
“Our nursing staff , patients, and others seem very happy with
the air quality in the facility,” he added.
In his estimation, HVAC maintenance has also been enhanced.
Th ough the hospital still does occasional pressurewashing
of a/c coils with water, they have eliminated the use of
acid for cleaning. In addition, drain pans stay clean and free of
organic debris, so no further cleaning of these components has
been needed, said Molano.
Rio Filter Supply performs all services on UVC Emitters, including
periodic checks and measurements of performance.
“Of course, we are pleased about the enhancement to our already
good IAQ, and with the ability to reduce or eliminate certain maintenance
tasks,” said Molano. “But right now, the energy savings we
are achieving with UVC are fi rst and foremost. Th is technology has
tremendous potential for all types of buildings and homes.”
It should be noted here that the 320-bed hospital has received
the Distinguished Hospital Award for Clinical Excellence for
fi ve years in a row (2003 – 2007) from HealthGradesT, considered
one of the nation’s leading sources for health care quality
information. Th is places the hospital among the top 5 percent of
all hospitals in the nation.
This chart shows the breakdown of utility cost savings achieved at Rio Grande Hospital after it installed UVC lights in the hospital’s air-handling units.
(Information provided by Steril-Aire.)
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