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Fig. 1. Comparative annual energy use by building type. All images courtesy of Ellenzweig except
where otherwise noted.
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With increasing energy costs added to the traditionally high costs of operating research
facilities, facility managers are redoubling their efforts to incorporate energy-saving features
in new research buildings. Not only does this save energy and operating costs, it also dovetails
with the growing institutional understanding of the global impact of energy use and the
endorsement of green design philosophy as represented by the USGBC LEED rating systems and Labs 21
standards.
Questions remain, however, about which energy-saving strategies to incorporate into new
building projects. In comparing the total annual energy use of research facilities with baseline
building types such as office or classroom buildings, the difference is staggering (Fig. 1).
Salient reasons for this discrepancy are that research facilities rely on heavy use of research
equipment requiring a constant power supply (and thereby compounding cooling loads). Research labs
may also require higher air change rates per hour to protect users from toxic fumes and
contamination (see Efficient HVAC strategies: An emerging technology primer for more information).
Redundancy requirements of the electrical and mechanical systems to safeguard valuable research
and protect animal facilities supporting biomedical research may also drive up energy usage.
The challenge therefore, is to explore the means to incorporate appropriate energy-saving
strategies in the design phase of research facility planning, thereby reducing the ensuing
operational costs for the life of the building, and creating increasingly minimal carbon
footprints.
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Fig. 1a. Responsibility for sustainable design and construction encompasses multiple members of
the project team.
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Fundamental team components
The successful incorporation of energy-efficient strategies in the design of new facilities relies
heavily on collaboration between the design team and the stake-holders of the client team. It is
therefore critical to define the composition of the design and client teams, which will jointly
articulate and set goals for energy conservation, and map the timeline for decision-making to keep
the project on schedule. In addition, the drive to incorporate energy-efficient strategies is
closely coupled with sustainability advocacy, whether on the client team or the design team or
both, giving momentum to creative thinking (Fig. 1a).
The group of specialists included in the design team typically consists of the architect;
mechanical/electrical engineers and civil engineers; an energy-modeling team that continuously
updates and tests input by the A/E team; and a cost-estimating team that is tasked with
calculating the capital costs of proposed strategies and collaborating with the A/E team to
estimate the life-cycle costs of these strategies. A potential organization of the client team is
highlighted in Fig. 2.
It is critical to understand the complexity of the client team organization at the onset of the
project. Each of the stakeholders will be viewing changes to the status quo from different points
of view. Thus vetting the issues and valuing the stakeholders’ input will improve the
strategy-evaluation process and likely result in a client team consensus and buy-in.
Energy conservation goals
Setting energy conservation and sustainable design goals will influence every aspect of a project,
whether in the mission of the building, the stated planning goals, the project schedule
(accelerated at times), the coordination of the trades and the cost analysis.
Energy conservation goals can be grouped into ideological goals and practical goals.
Ideological goals typically include aspirations for the project and are associated with a moral
imperative. For example, if there is a desire to attain the maximum possible energy performance of
the facility, the team can focus on ways to attain the goal. If a client states that the building
will target LEED certification to a given rating, the team will design to implement this goal from
the onset. Increasingly, many academic institutions are indicating that a reduced carbon footprint
is a desired objective for their projects (Figs. 3 and 3a).
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Fig. 2. Complex client team organization.
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Practical goals may temper ideological goals for a given project and are directly related to
what is achievable given the various stakeholders and their objectives. The program type—in this
case, scientific research—may engender limitations to energy conservation strategies. For example,
light levels at the research bench may be highly contested. The design team may advocate for
reducing light levels by improving the lighting quality, but the lab users may still demand high
light levels independent of lighting quality or available daylight.
Most often, economics and financial advantage dictate the terms of an acceptable payback period
for a return on the institution’s capital investment in energy conservation (often identified as
seven years). New technologies with a limited track record are often viewed with caution, with
questions regarding their reliability and whether they will require higher maintenance than
conventional ones.
Finally, the safety of the building occupants and maintenance staff is never negotiable, For
example, minimizing the number of air changes per hour in a research laboratory environment can
only go as far as is considered safe.
Timing is crucial
Generally speaking, in planning a research facility, the earlier the goal setting and evaluation
of strategies, the more likely the project schedule will proceed according to plan.
During the programming/predesign phase of a project, an evaluation of the “energy profile” of
the building will help determine the energy conservation goals.
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Fig. 3. Energy profile of a typical life science lab building.
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In the schematic design phase, global considerations include the grouping of similar types of
spaces, and the layout of the program to maximize conservation. Examples include grouping the
office and administrative functions, and grouping lab and lab support functions. The permanence of
space usage should be evaluated against the need for flexibility and adaptability over time.
Engineering design criteria can then be further defined in the schematic design and design
development phases. The capital investment in heating and cooling conservation measures and a
daylighting approach coupled with the design of a high-performance building envelope needs then to
be assessed against the payback period for each strategy on the one hand, and the resulting carbon
emissions reduction (which will eventually carry an associated cost or in some cases, an
incentive) on the other.
The glue cementing these strategies is in the design of advanced controls, which will allow the
building systems to function intelligently and on demand, limiting considerable waste. Fig. 4
summarizes the phases where typical sustainability decisions fall within the lab design
process.
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Fig. 3a. Buildings’ “green profile” will fall on a spectrum from conventional design (usually
connoting heavy energy use) to “carbon neutral” to climate-positive. Graphic courtesy of Atelier
10.
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Energy conservation and payback strategies
The key principles underlying the conservation of fossil-fuel-based energy revolve primarily
around reducing demand, increasing the efficiency of engineering systems, harvesting free energy
when available, recycling “waste energy,” and adaptive re-use of existing buildings whenever
possible.
- Reducing demand is one of the most effective steps in energy conservation. This
entails organizing the program and layout to maximize conservation (Fig. 5), optimizing the
building form, and selecting the most suitable orientation to better control solar heat gain.
Reducing demand also requires the team to carefully assess the appropriate sizing of the
engineering systems with load assessment and diversity.
For example, rather than using conventional design criteria for plug loads (W/ft2),
use historical data obtained from metering electrical loads in similar existing buildings. The
design setpoint could be reconsidered for a possible increase by a few degrees.
- Increasing the efficiency of engineering systems. Designing the mechanical,
electrical and lighting systems with greater efficiency will minimize energy waste. Chiller
systems operating with variable frequency drives (VFDs), and supply air systems designed with
variable air volume (VAV) boxes will respectively out-perform constant frequency drives and
constant volume air systems. Sizing the ductwork to reduce static pressure loss will improve the
efficiency of the air delivery. Lighting efficiency can be improved with use of compact
fluorescent and light-emitting diode (LED) lighting.
- Harvesting free energy. Investigating available renewable resources, such as solar,
wind and geothermal sources, may effectively contribute to reducing the fossil fuel based
consumption of energy. In some regions, it may be worth investigating government incentives that
would abate the cost of the capital investment, making it more attractive to the client. By
optimizing the orientation of the building, site permitting, heat gain/shading may effectively
contribute to reducing the demand on the engineering systems. Designing the lighting system of the
building such that daylighting is a major part of the lighting equation truly reduces the energy
consumption attributed to lighting.
- Recycling “waste energy.” Recycling “waste energy” can significantly increase the
energy performance of a building. Certain zones of the building can be designed to take advantage
of cascading and/or recirculating air systems. Other means of energy recovery can be integrated in
the engineering systems’ design (see “energy recovery devices” in Part 2, upcoming in
October).
- Adaptive reuse. Last but not least, the embodied energy savings in adaptive reuse of
existing facilities should not be underestimated. While these energy savings do not translate into
a direct financial advantage to the institution over the life of the building, they do save some
capital costs, and they are worth noting from an environmental standpoint: The amount of
CO2 emitted by the cement industry is nearly 900Kg of CO2 for every 1,000Kg
of cement produced.
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Fig. 4. Timing of the decision-making process.
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Sustainability from an owner’s perspective
The following analysis, related to the “Energy Saving Strategies” story, highlights the
owner’s perspective in assessing energy conservation strategies for the Koch Institute for
Integrative Cancer Research at the Massachusetts Institute of Technology, which will be completed
during the winter term of the 2010-11 school year. All the various constituents’ interests,
outlined below, were taken into consideration during the decision-making process, which resulted
in effective steps to reduce energy consumption while maintaining the highest standard of
operation for this research facility.
Administration’s goals: The owner’s ideological goals included a desire to design the
“right building,” to obtain a LEED Silver certification at a minimum, and to make a real
commitment to a substantive reduction in energy consumption thereby reducing the building’s carbon
footprint. For MIT’s administration, these goals needed to be anchored in a practical economic
reality, which mandated that integrated energy reduction strategies with additional first costs
had to have a projected payback of 7 years or less.
Environmental Health and Safety (EH&S) concerns: For this constituency, while the
safety of the building occupant was “non-negotiable,” stringent performance criteria were examined
more closely. Although not all energy reduction strategies were adopted, these included:
- Reduced air change rates.
- Reduced fume hood face velocity.
- Eliminating the venting of biosafety cabinets (normally required for student use).
- Integrating ventilation-on-demand technology.
- Having the ability to re-commission the engineering systems at lower rates.
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Fig. 5. This floor plan shows office and administrative spaces grouped to take advantage of a
recirculating air system. The labs, housing the researchers’ proprietary lab benches and write-up
desks, are aligned along the perimeter of the floor plate to take advantage of daylight.
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User/Faculty concerns: The faculty was preoccupied with compromising the convenience
of office-to-lab adjacency in favor of a grouped/zoned office layout that engenders energy savings
– conversely, the proposed zoning promoted faculty interaction. The faculty wished for built-in
flexibility to convert the labs from biology to bioengineering if needed over time. Such
flexibility implied added HVAC and fume hood capacity.
Accepting “risk” to enable “innovation”: In the end, MIT was able to take effective
steps to reduce the projected energy consumption of this state-of-the-art facility. Those
included:
- Limiting flexibility: Allowing a maximum of 1.5 fume hoods per 540 ft2 lab module,
for a maximum of 200 fume hoods in the building. The base design implemented one fume hood per lab
module.
- Supporting a dedicated office zone.
- Reevaluating conventional comfort standards (accepting 74°F vs. 72°F).
- Revising electrical and lighting assumptions (using metered data from similar facilities) to 5
W/ft2 plugload (vs. the conventional 8 W/ft2) and 1 W/ft2
lighting density target (Mass. Energy Code allows up to 1.5 W/ft2).
- Revising EH&S standards as follows: reduced air changes per hour to 6 ACH in occupied space;
reduced air changes per hour to 4 ACH in unoccupied space; designed fume hood face velocity to
achieve 80 fpm; potential to operate the fume hood with a face velocity of 60 fpm.
The table below compares energy usage of different MIT building program types: biology
research, brain research, health sciences, cancer research and classroom/code baseline. The Koch
Institute cancer building (under construction) is designed to significantly improve the energy use
profile compared to existing buildings, as shown.
MIT comparative energy use
data
Source: Table courtesy of the authors |
| USE
TYPE |
YEAR |
Electric
(cogeneration) Kbtu/ft2 |
Heating (steam)
Kbtu/ft2 |
Cooling (chilled
water) Kbtu/ft2 |
Total
Kbtu/ft2 |
| Biolgoy research |
1994 |
181 |
310 |
191 |
682 |
| Brain research |
2006 |
78 |
204 |
141 |
423 |
| Health sciences |
1982/2007 |
82 |
54 |
252 |
388 |
| Classroom (code baseline) |
2009 |
64 |
53 |
69 |
186 |
| Cancer research (in construction) |
2010 |
59 |
53 |
64 |
176 |
Next month
Next month, Part 2 of this article will examine ways to address specific aspects of energy
consumption, including thermal loads; electrical/lighting loads; air handling unit and fan energy
loads; energy recovery devices; and chilled water and cooling systems. Case studies from MIT,
Michigan State Univ., Iowa State Univ. and Yale Univ. will examine the concepts in action.
Steve Mahler, AIA, LEED AP, is a principal and Shirine Boulos Anderson, AIA, LEED AP, is an
associate principal at Ellenzweig, Cambridge, Mass. (www.ellenzweig.com). The firm provides master
planning, programming, feasibility study, in-house lab planning and architectural design services
to academic, institutional and corporate clients. Allan Ames, PE, is a principal at BR+A
Consulting Engineers LLC, a Boston-based firm (www.brplusa.com). The company provides
mechanical/HVAC, electrical, plumbing and fire protection engineering services, as well as
building commissioning.
