Ingenieur Vol. 75 ingenieur July 2018-FA | Page 67

determine actual savings created within an
individual facility by an energy management
programme. Its objectives are:
a) To determine how much savings have been
achieved;
b) To prove that the energy savings projects
have been successful; and
c) To quantify the performance of an
implemented Energ y Conser vation
Measure (ECM) by measuring and verifying
the energy savings.
In order for M&V outputs to be commonly
accepted by all stakeholders, they need to
adhere to certain protocols. One such protocol is
the widely-accepted International Performance
Measurement and Verification Protocol (IPMVP)
developed by Efficiency Valuation Organisation
(EVO), an international non-profit organisation.
Based on the IPMVP, energy saving is fully
expressed as:
Savings = (Baseline Energy
– Reporting Period Energy)
± Routine Adjustment
± Non-Routine Adjustments
Where,
Baseline energy = energy consumption measured
during the baseline period,
Reporting period energy = energy consumption
measured during the post-retrofit performance
period,
Routine adjustment = adjustment due to regular
changes in independent variables (such as
changing weather conditions, varying production
levels), and
Non-routine adjustment = adjustment due to
one-off or infrequent changes in energy use
or demand that occur due to changes in static
factors (such as building façade changes, extreme
weather events, building extensions and changes
to equipment).
Generally, there are two methods of measurement
in M&V, as shown in Figure 1:
1.) Retrofit isolation method
This type of measurement method is selected
to measure the performance of the energy
saving measure (ECM) only at the retrofit point.
The retrofit isolation method usually requires a
dedicated meter. There are two options available
under this method:
Option A: Savings are determined by
field measurements of the key performance
parameters (such as chiller power) which define
the energy use of ECM. The parameters not
selected for field measurement are estimated
from an established basis. (e.g. lighting retrofit-
power is measured meanwhile operating hours are
estimated based on facility schedules).
Option B: Savings are determined by field
measurement of all the parameters. (e.g. chiller
system retrofit).
2.) Whole facility measurement
This type of measurement method is selected to
measure the impact of ECM on the total energy
use in the facility. The measurement often uses
M&V Method
Retrofit Isolation
Option A
Whole Facility
Option B
Option C
Option D
Figure 1: M&V Options
65