LEED® +
District Energy
What Do You Mean I
Need to Commission
My Plant?
Answering the call
Tim Griffin, PE, IDEA USGBC Liaison
Editor's Note: “LEED® + District Energy”
is a quarterly column providing information
about the U.S. Green Building Council’s
LEED® rating system and how it applies to
district energy systems and the buildings
they serve.
“What do you mean you can’t get your building certified as green if you
connect into my plant?” you shout into
the phone. “My district energy plant is
efficient! And what does commissioning
my plant have to do with your building?”
you continue.
Calls like this one are occurring across
our industry. Developers, colleges and universities, Fortune 500 companies and others
are all trying to certify their construction
projects through the U.S. Green Building
Council’s LEED® (Leadership in Energy and
Environmental Design) Green Building Rating
System™. There is much confusion about
how the guidelines are to be applied when
a building receives district energy service –
especially in the area of commissioning.
Can a building project be prevented from
obtaining LEED certification by connecting
into your plant just because the plant has
not been commissioned? The answer is a
resounding maybe. Let me explain.
The What and Why
of Commissioning
Commissioning is a quality assurance
process designed to help owners get the
facilities they envisioned. Fundamentally, the
process is designed to provide plant owners
and operators with an understanding of how
all of a building’s systems are supposed to
interact; ensure that the owner’s vision does
not get compromised during design, construction or turnover; and test all system
interaction to ensure proper functionality
under all possible operating conditions.
The USGBC’s goal with the LEED program is to encourage the development and
operation of energy-efficient buildings. What
the council discovered, however, is if a
building is designed to be energy-efficient
but is not commissioned, it will not operate
that way. So early on, commissioning became
a requirement within the LEED rating system.
Fundamental commissioning is
actually a prerequisite for LEED
certification.
Fundamental commissioning is actually
a prerequisite for LEED certification – and
one that does not confer any points toward
that goal, which reflects how important it
is to the USGBC. As defined by the LEED
rating system, fundamental commissioning
requires the project team to designate a
commissioning authority to lead the process,
review the owner’s project requirements and
the designer’s basis of design, develop and
incorporate commissioning requirements
into the construction documents, develop
and implement a commissioning plan, verify
the installation and performance of the
systems to be commissioned, and complete
a summary commissioning report.
The USGBC also encourages project
teams to pursue enhanced commissioning
activities by assigning these activities points
equal to 5 percent of the total points needed
for basic certification. Enhanced commissioning, as defined by the LEED rating system,
requires the commissioning authority to be
independent of the design and construction
team. That commissioning authority, or
agent, must also begin design reviews before
the midpoint of construction document
development, review contractor submittals
of systems to be commissioned, create a
systems manual that provides future operating staff the information needed to optimally operate the systems, verify training
requirements have been completed, and
perform a warranty review 10 months after
substantial completion.
How About the Plant?
During the first 10 years of the LEED
program, little guidance was provided as
to how to apply commissioning requirements to a district energy plant that serves
a LEED-applicant building. The lack of
guidance created much confusion with
regard to commissioning. For instance, if
utility services are generated within the
LEED-applicant’s building (e.g., steam from
boilers, chilled water from chillers), commissioning of the generation equipment
has always been required; if generated off
site in a central plant, the commissioning
requirement for generation equipment
was unclear. Prior to issuing its first district
energy guidance document in spring
2008, however, the USGBC came to a
consensus on this issue and provided clarification within that document.
On the matter of commissioning, the
USGBC determined it did not want an
applicant building to be prevented from
getting LEED certification just because it
