Central Tower offices, Melbourne Intelux controllers for lights intelligent management
Intelux controllers for lights intelligent management
Background

The Central Tower in Melbourne is a good example of the application of lighting control in office buildings. It is a 19 storey-building, where each floor has both open plan type offices as well as more conventional wall partitioned offices. Each floor uses 226 compact fluorescent lamps (36W twin type ), with conventional power supply. This amounts to total of 8588 light sources and an overall installed power of about 370 kW.

The solution

Having decided that rational management of energy uptake would be of the main savers in the installation plant restructure project, Intelux emerged as the system most capable of guaranteeing the best ratio between price and performance.
Each lamp line was supplied with its own controller placed in a special niche in the ceiling at the circuit input. 20 controllers were installed on each floor, each with a power ranging between 2,5 and 4,0 kVA. The only additional operation required was to reposition the power correction capacitors at controller input. The controllers are piloted (in groups) by 8 photocells placed on the ceiling near the served area in order to gauge average lighting level, which is a mixture of natural daylight and artificial light. This lay out consents each photocell to be independently set at required lighting level, according to the real operational needs of the area to be controlled. The integration of Intelux controllers with the Staefa Building Automation system has made this building an exemplar, avant-garde project from an aspect of energy uptake optimisation and environmental quality.

The benefits

The installation of Intelux system has brought about and average annual saving of 40%. Data retrieved during a 4-month test carried out on one of the office block floors spoke about average savings in the order of 48.2%. Given that the test was conducted on lamps that had already been in service for one year, makes these results particularly significant.

Application technical details
Annual working hours 3400 h
Consumption without INTELUX 1255,6 MWh
Consumption with INTELUX 753,4 MWh
Annual saving percentage 40%
Energy cost 0.105 €/kWh
Annual energy saving 52.913 €
INTELUX system cost 141.302 €
Installation costs 23.550 €
Public financing - 69.473 €
Net investment cost 95.379 €
Pay back time 1,8 years