Retrotec USACE - Manual (Page 81)

Chapter 7 59
7.3 Ongoing/Continuous Commissioning Provides Energy
Assessment Technologies for Energy Management
Energy management is a process that goes on over the whole life cycle of a
building. Phases such as planning, commissioning, auditing, and operation
control contribute essentials to energy management.
In the context of this report, “energy management” means the systematic
procedure of how to ensure permanent energy effi ciency in the buildings that
were visited during the energy assessment.
Continuous confi rmation of the energy effi ciency is necessary primarily
because
HVAC systems, like all technical systems, have to be checked against ■
faults and faulty operation
Changes in building use have to be taken in account and might need
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changes in the defi nition of comfort and in system operation
Continuous confi rmation of the energy effi ciency is obtained through
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continuous commissioning (energy assessment during operation)
Rules that hold for the analysis of energy conservation measures are similar
to those already derived for the energy assessment team. The team that performs
the continuous commissioning has to keep in mind that the aim may not be to
identify all saving opportunities, but to concentrate on the low-hanging fruit and
no-cost measures. Identifying no-cost measures during continuous commission-
ing requires knowledge about the systems and their operation. These are usually
things related to operation schedules, setpoints, and operation of the energy-
using systems. Identifying long payback measures is derived from fault detection
and diagnosis. Samples are: the systems need thorough improvement (change of
boiler, installing a new chiller with free cooling, replacement of windows, etc.).
Ending up with no saving potential is even more unusual during energy
assessment. If the building, after a successful energy assessment, is operated
well, there may not be any savings opportunities without a major renovation.
Again it holds that zero potential is a good result: it shows that everything is
working as it should and the O&M staff knows what they are doing.
Thus, the main difference between energy assessment and continuous
commissioning is that through energy assessment one can identify ESCOs that
might lead to considerable energy savings while through continuous commis-
sioning one avoids developments that need to be corrected through ESCOs.
Consequently, there are some essential differences between standard energy
assessment and energy assessment during operation. They include
The savings cannot be proven directly. An “optimized building” cannot ■
be improved. Ineffi ciencies and waste that are eliminated as soon as they
start to appear cannot be proved through energy savings in bills.
The potential savings (average 5–10% per year) are in the bandwidth of
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the usual uncertainties and can therefore always be argued.