continued on page 7
Sustainability in labs
continued from page 3
Perkins Eastman project illustrates this
scenario. In the process of adding several
floors to a lab building built 10 years ago,
Perkins Eastman added an energy-recovery system to serve the old and new space.
Despite the addition of one-third more
built square footage, the energy usage of
the building remained flat (Figure 2).
• Air changes. A complementary energy-conservation strategy is to find ways
to drop ventilation rates to the required
minimums whenever possible. One strategy employs occupancy sensors that, while
they control lighting, instruct the Building
Management System (BMS) to drop to
minimum allowable air changes while the
lab is unoccupied. There are also demand-based HVAC systems that use independent
sensors and the BMS system to address the
individual needs of each space by monitoring temperature, humidity, CO2 levels and
even sensing chemical spills and ramping
up ventilation as needed.
A strategy of lower air change rates may
be ultimately implemented in conjunction
with a supplemental cooling system and
planning approaches that isolate large
equipment and their resulting heat load.
Removing excess heat from a space using
fan-coil units or chilled beam systems
• Light and heat. When coordinated
properly, some planning strategies can
simultaneously elevate occupant comfort while increasing building efficiency.
Maximizing exposure to natural light will
introduce the opportunity for automatic
dimming of electric lighting. The design
team can further study zoned lighting connected to occupancy sensors and reduction
of general fixture quantities by introducing
individual task lighting. The interior zones
of a building are a natural fit for equip-ment-heavy spaces, such as cold rooms and
microscopy and refrigerator rooms, that
don’t benefit from sunlight. Additionally,
any strategy to isolate the heat and noise
generated by large equipment from staff
seating areas will enhance comfort, as well
as the ability of the engineering team to
control the environment.
• Technology. With the increasing dependence on databases, statistical analysis and
information sharing, technology integration
will play a significant role in any new facility.
In terms of sustainability, accommodations
should be considered for video conferencing
or remote education. Use of space and infrastructure with this type of technology will
inevitably increase in the coming years, as the
process becomes more fluid and as the younger generations become the workforce majority.
In this way, more people can be included with
The high demand on lab infrastructure
is perhaps the most salient and challenging
aspect of sustainable lab design. Addressing
the issue of energy consumption while
respecting code mandates requires smart
engineering and a collaborative design
team. Lab guidelines and codes require certain minimum air change rates for occupied
and unoccupied labs. Often due to the heat
generated by people, equipment and computers, ventilation rates can elevate to as
much as triple the required minimums.
• Energy recovery. As a result of the
restrictions on recirculating lab air, all the
energy that goes into heating or cooling the
air will be lost when the air is exhausted if
there’s no energy-recovery system in place.
While the upfront cost must be considered,
energy-recovery systems—whether a desiccant wheel, a plate-to-plate exchanger or a
glycol loop—will dramatically reduce energy cost for the life of the building. A recent
can more efficiently tap into chilled water
loops. The piping required to carry the heat
away will take up far less ceiling space than
the comparable ductwork and can more
easily accommodate future modifications.
This can ultimately result in a lower floor-to-floor height requirement and subsequent cost savings.
• Fume hoods. For a long time, fume hoods
have been one of the more difficult energy
loss problems to solve. Fume hoods exhaust
a significant amount of air in order to keep
the operator safe and maintain a minimum
face velocity. Fortunately, new technologies
and regulatory adjustments have made it
possible to alleviate the problem. Minimum
face velocity requirements have been reduced,
providing the installed hoods meet ASHRE
110 requirements. High-efficiency hoods are
available to produce more draw while expelling less air, and variable-air-volume controls
can modulate the air velocity based on the
sash opening. Optional sensors will automatically lower the sash when the operator steps
away, reducing the amount of air and, thus,
energy lost. And in certain lab environments,
new ductless fume hoods are an option that
eliminates the problem and a significant
amount of costly ductwork, as well.
Figure 2: Lab building addition with energy-recovery system at the Univ. of Arkansas Reynolds Center on Aging.
Image: Perkins Eastman
6 LaboratoryDesign|JAN|FEB 2015