Traditional data centers utilize air-cooled
equipment. Unfortunately, air is a poor conductor of heat and has a high transport energy.
In contrast, water is an excellent conductor of
heat and has a relatively low transport energy.
Recently there’s been a resurgence in water-cooled data center equipment, particularly for
high-performance platforms. Water cooling
allows for higher rack power densities with
the potential to generate a high quantity of
“waste” heat. When captured in the form of
water, the server heat is no longer wasted, but
can be effectively applied for building heating.
The heating available can be used not
only for labs, but office heating as well.
When integrated on a campus, these sys-
tems can serve other facilities; and with
proper planning could ultimately allow the
data center to become a significant part of
the heating plant for the campus. The U.S.
Dept. of Energy (DOE)’s National Renewable
Energy Laboratory (NREL)’s Energy Systems
Integration Facility (ESIF), R&D Magazine’s
2014 Laboratory of the Year, takes advantage
of this system integration.
Robert Thompson is a registered professional
engineer and chief mechanical engineer for the
S&T studio in the Phoenix office. Thompson’s designs focus on the environmental design specifics
that influence the energy and sustainable performance of buildings. Otto Van Geet is a Principal
Engineer at the DOE’s NREL.
Energy optimization and reuse
through systems integration
continued from page 27
data center was reused to the lab, there’s the
potential for a sizeable heating reduction. At
the same time, this heating reduction for the
lab translates to a cooling reduction for the
data center. The net effect of this integration is
an energy-use reduction for both programs. As
water is typically used in the process of data
center cooling, there’s also a corresponding
water-use reduction.
A zero-net-energy teaching lab
By: Jacob Knowles, Director of Sustainable
Design, Bard, Rao + Athanas Consulting
Engineers LLC
The 50,000-sf New Technology and Learning Center (NTLC) for Bristol Community College (BCC) in Fall River,
Mass., brings together currently disparate programs from across campus, including chemistry, biology and medical and dental education.
It holds an energy-dense program, including 22
fume hoods, high plug loads and specific ventilation and lighting requirements.
Initially, a standard high-performance building served as the basis of design for the NTLC,
including numerous energy-conservation
measures (ECMs). It was designed to meet the
statutory requirement of Massachusetts LEED
Silver Plus, including a minimum of 20% ener-gy-cost reduction, compared to the ASHRAE
90.1-2007 baseline.
While the project was on hold awaiting funding, BCC doubled-down on their commitment
to achieving carbon neutrality for their entire
campus operations by the year 2050, initiating
plans to develop a campus-scale photovoltaic
(PV) array over one of their existing parking
lots. Given this new context, when the NTLC
project was authorized by the state to proceed,
Sasaki Architects and BR+A took a closer look
at the original “high-performance” design.
Our detailed energy model of the high-per-
formance design showed the NTLC would
use approximately as much electricity as the
existing campus, as well as a natural gas equiv-
alent to the consumption of 120 homes. Given
the NTLC would only be half-way through its
lifespan by the year 2050, the high-performance
design clearly wasn’t keeping pace with BCC’s
vision.
Over the following weeks, BR+A and Sasaki
made a strategic investment to develop a
zero-net-energy (ZNE) design in parallel with
the high-performance design. To start the process, we searched for precedent ZNE buildings.
Of the seven similar projects identified, four
were either in design or construction. Although
laudable projects, those built appeared to fall
short of their ZNE goals. Only one of the built
projects, located in the mild California climate,
had significant exhaust demand. So the question remained of how to achieve ZNE for an
energy-dense program in a cold climate.
Beginning with a series of potential solu-
tions, the NTLC team vetted these options
through exhaustive building simulation, calcu-
lations, research and discussions with manufac-
turers of advanced building technologies. BR+A
also performed a comprehensive plug-load
study, plugging in every piece of equipment
going into the new building to right-size the
cooling and electrical systems. We then inter-
viewed key staff and faculty to understand how
equipment is used for each class and integrated
dozens of load profiles into the energy model,
based on the actual academic calendar to maxi-
mize the accuracy of the energy analysis.
Ultimately, a synergistic combination of
old and new technologies was developed. The
ZNE design relies on a hybrid ground-source/
air-source heat pump system with expanded
ground-temperature range and an advanced
optimization control logic, filtered fume hoods,
enthalpy wheel heat recovery, reduced mini-
View of the Bristol New Technology and Learning Center. Image: Sasaki Associates