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BEAM P
LUS
I
NTERIORS
C
OMMERCIAL
, R
ETAIL
A
ND
I
NSTITUTIONAL
A
PPENDICES
9.1 A
SSESSMENT
F
RAMEWORK OF
E
NERGY
P
ERFORMANCE
Copyright © BEAM Society Limited. All rights reserved. Page 125
9.1 A
SSESSMENT
F
RAMEWORK OF
E
NERGY
P
ERFORMANCE
9.1.1 Energy Assessment Framework
9.1.2 Energy Assessment Approaches
9.1.3 Performance-based Approach
9.1.4 Prescriptive-based Approach
9.1.1 E
NERGY
A
SSESSMENT
F
RAMEWORK
The assessment framework described herein applies to all space
types:
i.
those that are air-conditioned throughout the year;
ii.
premises that are air-conditioned, either by a central plant
serving the entire project area or unitary equipment for
individual spaces;
iii.
premises that are air-conditioned by a central plant shared
with other portions of the building;
iv.
premises that adopted passive design;
9.1.2
E
NERGY
A
SSESSMENT
A
PPROACHES
To accommodate various types of projects and for flexibility to achieve
the energy performance target for a project, the Applicant can freely
choose one of the given approaches (i.e. Performance-based or
Prescriptive-based Approaches) based on their project situation and
resources for the assessment of energy performance.
9.1.3
P
ERFORMANCE
-
BASED
A
PPROACH
The Performance-based Approach is used for assessing the Annual
Energy Use for HVAC&R and lighting systems. The Annual Energy
Use is estimated by computer simulation and is based primarily on the
‘Energy Budget’ approach, supplemented by a range of basic
requirements.
The Code of Practice for Energy Efficiency of Building Services
Installations (BEC) [
1] provides a framework for demonstrating
compliance in which the proposed design has annual energy
consumption no greater than that of a reference case that satisfies the
prescriptive requirements.
The Performance-based Approach described in Section 9 of the Code
of Practice for Energy Efficiency of Building Services Installations is
primarily geared towards demonstrating compliance to performance
requirements in section 5 to 8 of the BEC. A number of important
modifications are listed here for extending the BEC’s Performance-
based Approach for the purpose of quantifying energy reduction as a
result of efficient design.
Energy Reduction Measures Considered for this credit
The major modifications concerns clause 9.5.4.1 in BEC, which states:
In fulfilling clause 9.5.3 (the requirement that the design energy should
not exceed the energy budget), the increase in design energy as a
result of not satisfying the trade-off allowable requirements in clause
9.4.2 (performance requirements for lighting, air-conditioning, lift and
escalators, electrical installations) of BEC, can be off-set with
reduction in design energy as a result of –
i.
An improvement over the corresponding minimum allowable
levels of performance in any one or more of the items listed
with energy efficiency requirements in Sections 5 to 8 of the
Code (lighting, A/C, vertical transport and electrical), [This
clause effectively limits the baseline A/C system to be the
1
Electrical and Mechanical Services Department - Code of Practice for Energy Efficiency of Building Services
Installation 2012