48 LIGHTING MAGAZINE | June/July 2013 June/July 2013 | LIGHTING MAGAZINE 49

C A S E S T U D Y

INTRODUCTION

Located in the heart of the CBD, the

commercial tower at 215 Adelaide Street has

graced Brisbane’s landscape for 30 years. In

2008 Norman Disney & Young recommended

a plan to improve tenant services and reduce

energy consumption – a plan that would

elevate the energy rating from 2.5 to 5 National

Australian Built Environment Rating System

(NABERS) Stars and go on to claim the Award

for Best Sustainable Development – Existing

Buildings at the 2013 National PCA Award.

A comprehensive building services upgrade

was planned and implemented

in a staged manner that included:

z Building investigation and energy

assessment report;

z Proof of concepts and NABERS thermal

energy modelling;

z Detailed design, tender and NABERS pre-

commitment certification;

z Construction and commissioning; and

z Fine tuning and monitoring.

In early planning, all elements of the

building services were investigated, including:

lighting; lifts, ventilation and air conditioning

(HVAC) and water pumping. Each of the

various improvement options were assessed

in terms of energy savings, benefit to the

NABERS rating, age and condition of the

services and value/risk to tenants. With the

support of detailed calculations including

NABERS thermal energy modelling the

client decided to proceed with a suite

of complimentary building services

improvements which included: chiller plant;

cooling towers; pumps; fan motor variable

speed drives

and a major lighting upgrade.

Of all the options accepted, the lighting

upgrade offered the highest cost per

NABERS point and high tenant risk, since

the works had to be completed within

tenant occupied areas. In an existing

building, the lighting upgrade represents

a key opportunity to deliver a range of

benefits in addition to the obvious energy

savings and energy ratings.

THE EXISTING BUILDING

The general lighting throughout the building

was original, comprising twin 36W tube

recessed troffer luminaires with clip on light-

air boots mounted in a 1-way ceiling grid.

This combination introduced significant risks

with the luminaires effectively supporting

the ceiling tiles along one edge and wholly

supporting the supply air diffusers.

The lighting was originally installed with

a proprietary central lighting control and

wiring system that had been modified over

the 30 years of tenant fit-outs. As a result,

the existing luminaires were installed with

a variety of different plug connections

and tenant control systems. To minimise

construction complexity and operational

risk to the tenants each luminaries was

rewired outside normal operating hours.

By Connan Brown Norman Disney & Young

Retrofitting a 30 year old Brisbane commercial tower

The energy rating was elevated from 2.5 to 5 NABERS Stars following the retrofit at 215 Adelaide Street, Brisbane.

50 LIGHTING MAGAZINE | June/July 2013 June/July 2013 | LIGHTING MAGAZINE 51

Each luminaire was calculated to

consume approximately 90W, including

magnetic ballast losses. A building

inspection and initial illuminance

calculations confirmed that an upgrade

to single lamp T8 would be the most

technically feasible option with energy

savings in excess of 50% or 50W per

luminaire.

T5 VS T8 TECHNOLOGY

There is a market perception that

energy efficient lighting needs to utilise

T5 lamp technology and this was a

major cause of debate during lighting

design development. 28W or even 25W

T5 lamps are being used in modern

office buildings to deliver increasingly

lower lighting power consumption. What

is interesting is that much of this energy

improvement is coming from lighting

refractor and reflector technology —

not just the lamp. As a result, single T8

lamps have the potential to compete

with T5 luminaires, depending on the

project specifics of ceiling grid, floor

plate and air diffusion technology. The

physical characteristics of the building

demanded T8 luminaires and detailed

calculations showed equivalent lighting

energy consumption to T5 but with one-

for-one replacement. This result was

critical in establishing the viability of

the lighting upgrade, since one-for-one

replacement allows the work to proceed

without any impact to the layout of

the tenants ceiling services or lighting

control.

NABERS RATING SYSTEM

Under NABERS, lighting energy is

attributed to the tenant and general

office lighting reductions do not

directly impact the NABERS base

building energy rating. Commercial

buildings services system interactions

are complex, however, any energy

saved by the lighting system reduces

the internal heat loads on the HVAC

that directly impacts the NABERS

base building rating.

General office lighting becomes

effectively ‘free heating’ and is

undesirable in Brisbane’s subtropical

climate. However, in cooler climates a

lighting upgrade would increase base

building heating demands and may

even lower the NABERS base building

rating. For this reason thermal energy

modelling can be critical to gauge the

net benefits for any building upgrade

targeting improved energy ratings.

The NABERS thermal energy model

demonstrated that the lighting upgrade

would deliver direct energy savings to

tenants of 1.5 NABERS Tenant energy

stars but only 0.3 Stars benefit to the

NABERS Base Building energy rating.

The energy modelling was also

used to as the technical basis for

NABERS pre-commitment agreement

at a 4.5 Star level. This certification

agreement allowed the building’s

planned future rating to be advertised

to market prior to the works having

being completed and the data

collected.

IMPROVED ELECTRICAL CAPACITY

AND TENANT FLEXIBILITY

In addition to energy and ratings, the

lighting upgrade to open plan office

areas reduced the load on the tenants’

power by 7-9 W/m2. In addition, the

electronic control gear significantly

improved the power factor of the

lighting system, freeing up additional

kVA capacity of up to 13-14 VA/m2.

This significant boost to available

electrical capacity provided excellent

and much improved flexibility to the

building tenants. Buildings of this age

were designed for 5 or possibly 10W/m2

tenant equipment allowance that was

appropriate at the time but much less

that the 15W/m2 expected for premium

and A-Grade Buildings now.

A flow on effect of the reduced

lighting load is freed up cooling capacity

within the building HVAC system, not

only saving energy but also improving

building comfort and tenant flexibility.

EXCELLENT LIGHTING LEVELS AND

UNIFORMITY WITH LOW GLARE

REFRACTORS

The single tube luminaires were

specified with custom reflectors and

Y5 refractors. While critical to achieving

the energy savings target, this solution

ensures excellent lighting uniformity and

appropriate illuminances with low glare.

The Y5 refractors have a very shallow cut

off angle, producing ceiling luminances

and contributing to a sense of lightness in

the space. Tenant feedback indicated good

lighting levels were achieved with a strict

100 hour lamp burn-in policy implemented

in the building. Measurements showed

that the illuminances delivered by the T8

fittings were in line with expectations.

ENERGY COST SAVINGS

Using today’s electricity rates, the whole

building upgrade has saved $460,000 in

annual electricity costs. Put another way, if

the upgrade hadn’t occurred, the tenants

would be paying 65% more for electricity

today compared with that of 2008. The

energy cost saving associated with the

lighting upgrade contributed $100,000 or

more to this saving.

In addition to energy and ratings the lighting upgrade to open plan office areas reduced the load on the tenants’ power board.

The physical characteristics of the building demanded T8 luminaires and detailed calculations showed equivalent lighting energy consumption to T5 but with one-for-one replacement.

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TENANT DISRUPTION DURING

CONSTRUCTION

Tenant disruption was managed through

smart design, effective communication

and well-managed site work. The single

most important factor in limiting tenant

disruption was to provide one-for-one

luminaire replacement; ensuring no impact

on tenant lighting levels, on-floor wiring

or tenant lighting controls. The luminaire

supplier modelled the new on the old to

ensure that they would integrate into the

ceiling system, still providing light-air boot

and ceiling tile support in the 1-way grid.

The building manager provided tenant

presentations on the good reasons for

undertaking the works (saving energy

and reducing greenhouse gases) and

regular updates on the works. The main

contractor and electrical subcontractor

worked closely with building management

and building security to complete work

in strict accordance with a work plan to

I E S C O R P O R A T E M E M B E R S

Domus Lighting Pty Ltd New South Wales Corporate

ECC Lighting + Living Ltd – NSW New South Wales Corporate

Gamma Illumination New South Wales Corporate

Harcroft Lighting – NSW New South Wales Corporate

Jadecross Pty Ltd New South Wales Corporate

JHA Consulting Engineers Pty Ltd New South Wales Corporate

JSB Lighting Pty Ltd New South Wales Corporate

Klik Systems Australia Pty Limited New South Wales Corporate

Lighting Australia Pty Ltd New South Wales Corporate

Opal Lighting Systems New South Wales Corporate

Optic Fibre & LED Lighting Solutions Pty Ltd New South Wales Corporate

Stramac Pty Ltd New South Wales Corporate

Sylvania Lighting Australiasia Pty Ltd – NSW New South Wales Corporate

Total Electrical Connection Pty Ltd New South Wales Corporate

Tridonic Australia Pty Ltd New South Wales Corporate

Vossloh-Schwabe Deutschland GMBH New South Wales Corporate

Walter Wadey @ Co Pty Ltd New South Wales Corporate

Webb Australia Group New South Wales Corporate

York Precision Plastics New South Wales Corporate

Eagle Lighting – Fagerhult New Zealand Corporate

eCubed Building Workshop New Zealand Corporate

Inlite New Zealand Corporate

Klik Systems’s agent – Mark Herring Lighting New Zealand Corporate

Belltronic Lighting Solutions Queensland Corporate

GM Poles Queensland Corporate

Intralux Australia Pty Ltd Queensland Corporate

Klik Systems QLD Queensland Corporate

Lumen8 Architectural Lighting Queensland Corporate

Orca Solar Lighting Pty Ltd Queensland Corporate

Orion Solar Pty Ltd Queensland Corporate

Solus Lighting Solutions Queensland Corporate

Sylvania Lighting Australisia Pty Ltd – QLD Queensland Corporate

Valley Lamps & Lighting Queensland Corporate

Webb Australia Group Queensland Corporate

Eagle Lighting Australia South Australia Corporate

JSB Lighting South Australia Corporate

Klik Systems’s agent – H.I Lighting S.A South Australia Corporate

Sylvania Lighting Australasia Pty Ltd – SA South Australia Corporate

ANL Lighting Australia Pty Ltd Victoria & Tasmania Corporate

Cundall Johnson & Partners Victoria & Tasmania Corporate

ECC Lighting & Living – VIC Victoria & Tasmania Corporate

JSB Lighting Victoria & Tasmania Corporate

Klik Systems’s Agent – Southern Lighting & Distribution Victoria & Tasmania Corporate

Sonic Lighting Victoria & Tasmania Corporate

Sylvania Lighting Australasia Pty Ltd – VIC Victoria & Tasmania Corporate

Tridonic Australia Pty Ltd Victoria & Tasmania Corporate

Webb Australia Group Victoria & Tasmania Corporate

JSB Lighting Western Australia Corporate

Klik Systems’s agent – H.I. Lighting Western Australia Corporate

Metera Lite Western Australia Corporate

Mondoluce Western Australia Corporate

Sylvania Lighting Australasia Pty Ltd – WA Western Australia Corporate

FINANCIAL CORPORATE SPONSORS AS OF JUNE 2013

8600

8102

8100

8101

8103

8000

8300 8301

8400

8401

Available for all the most used COB LEDs:Bridgelux, Citizen, Cree, LG, Tridonic, Seoul, Sharp.

Always evolving to meet the market’s needs.

The product range is now complete.

These products

were developed step

by step with different

COB LED manufacturers,

reflecting our clear a

pproach

with our partn

ers.

8000 Series holders for COB LEDs.

ensure that tenants were pre-warned

of potential disruption. The installation

started only after a dilapidation inspection

and was conducted at night and in the

presence of building security guards. In

addition, drop sheets were used to protect

desks from dust and debris from the

ceiling void and all floors were cleaned

prior to the first arrivals the next day.

BENEFITS TO SOCIETY

According to the Queensland government,

peak demand growth has a cost of

$3.5 million per 1MW, with these

infrastructure costs fuelling rampant

electricity price increases. The upgrade

has reduced the building’s peak demand

by 1.2MVA, with the lighting upgrade

contributing almost 0.35 MVA – a possible

benefit in excess of $1 million to the state

and electricity consumers.

This benefit, in fact, approaches the

cost of the upgrade.

PROJECT CREDITS

z Pramerica – Building Owner

z Norman Disney & Young –

Consulting Engineers, NABERS

& refurbishment specialists

z Jones Lang LaSalle – Building

and Facilities Management

z John Outhwaite & Associates –

Project Management

z Built – Main Contractor

z KLM – Electrical Sub Contractor

z Moonlighting – Lighting

Technology Supplier