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Medical Construction & Design | NOV EMBER / DECEMBER 2017 | MCDM AG.COM
In the healthcare fi eld,
where sustainability and
building performance are
measured by energy effi ciency
and hospitals are graded on
patient outcomes and sat-
isfaction, Ascension has set
particularly high standards for
these objectives. In planning
Dell Seton Medical Center at
The University of Texas, a new
teaching hospital in Austin, the
owner tasked its design team,
including HKS, the architect
and WSP USA, the project's
mechanical, electrical and
plumbing engineer, to develop
innovative solutions to support
the highest standards of care,
reduce energy use and cost and
ensure sustainability.
In turn, the owner em-
braced the architectural and
engineering practices em-
ployed in the project to support
the attainment of these goals.
Among these, MEP strate-
gies to reduce and optimize
energy use and water use were
designed to contribute to at-
taining a minimum of LEED
Silver and Austin Energy Green
Building certifi cations and
patient care goals.
Reducing energy use
with dual-wheel AHUs,
heat recovery chillers
One of the major MEP en-
gineering challenges of the
project was achieving the
owner's requirement for 100
percent outside air delivery to
patient rooms, while attain-
ing a minimum certifi cation
of LEED Silver in the warm,
humid climate that typifi es
Austin. A typical air handling
system would mix outside air
with return air from the build-
ing, and then pass the mixed
air through a coil in an air
handling unit to cool the air to
approximately 50 F and bring
the humidity ratio down to 55
grains of moisture per pound
of dry air. Variable air volume
units in each patient room and
other occupied spaces would
then reheat the air, if necessary,
to satisfy the space's tempera-
ture setpoint.
The innovative mechanical
engineering strategy at Dell
Seton decouples cooling and
reheating using a "dual-wheel"
energy recovery system for
the patient rooms. The 100
percent outside air fi rst passes
through an enthalpy wheel,
where it exchanges energy
A look at how MEP design,
automation infl uences
sustainability strategies
BY SHAUN GRIMM | PHOTOS BY CASEY DUNN
GREEN
DRIVERS