The site

The Gauge is located in the heart of the 30 hectare Victoria Harbour area in Melbourne’s Docklands, which is being developed by Lend Lease Development. The building is located at a central address and is close to green space and a retail precinct.

Sustainability initiatives in the building include a black water treatment plant, a gas-fired cogeneration system providing base building electricity and utilising waste heat for pre-heating air supply in winter months and domestic hot water. The building also utilises passive chilled beam cooling using water as a cooling mechanism, two full height atriums acting as a heat buffer and ‘chimney’ to extract warm air from the building, cyclist facilities with additional allowance for visitors, storm water redirection to irrigate local landscaped areas and energy efficient shading on the building’s façade.

Design and layout

The building draws significant inspiration from the industrial and port handling heritage of the Melbourne Docklands. The ‘purpose build’ nature of industrial structures and the historic port handling facilities have also influenced the building’s design. The environmental goals set for the project saw its design follow a sustainable ‘form follows function’ approach.

Generation

The Gauge responds to the two significant environmental challenges facing Australia – greenhouse gas emissions and water supply.

A gas-fired cogeneration unit is located on the roof of the building, providing electricity for the base building systems with significantly reduced greenhouse gas emissions compared to coal-fired power generation. Waste heat from the cogeneration system pre-heats the air supply in winter months and provides domestic hot water.

A sub-metering plan, in line with Green Star requirements has been provided to enable energy to be closely monitored, faults to be identified quickly and systems to be tuned for maximum energy efficiency.

Daylight access

Access to natural daylight has been maximised for the office interior by four planning and design principles.

The side core configuration with a nominal floorplate size 1. of 21 metres by 70 metres ensures daylight penetration is maximised.

The curtain wall system utilises high performance glazing in 2. a floor to ceiling format, featuring external sun shading. This provides for optimal solar control and daylight penetration to the north, west and south building façades.

The eastern atriums maximise daylight access to the workspace. 3. Here, the atrium glazing is fixed to a steel structure braced from the floorplate edge.

The side core has been planned to allow for numerous window 4. openings to maximise access to natural light.

Air quality

The indoor air quality of the building incorporates a single pass passive chilled beam air handling air-conditioning system. The system provides high quality fresh air content, utilising the dual glass atriums for return and exhaust air purposes. This use of the atrium has determined the curved rooftop profile of the building. The beams provide space cooling passively — without the need for active air movement through the use of fans. The majority of the cooling is delivered by a hydronic system, which is more energy efficient than delivering through an air system.

Water conservation

The Gauge includes a black water recycling plant that delivers water recycling at lower energy consumption levels, lower chemical consumption levels and requiring less maintenance than previous schemes. The recycling system is integrated into the base building plumbing design and has a capacity to treat 10,000 litres per working day of office strength wastewater.

It is anticipated that 92 per cent of water, or 2.4 million litres, will be recycled at the plant per year. Remote monitoring means that the plant can be controlled from any location via a laptop computer and a dedicated ADSL line.

Gauging performance

In order to assess the performance of The Gauge in operation, targets have been established to monitor the development’s energy and water consumption. These will be monitored and benchmarked against the National Australian Built Environment Rating Scheme (NABERS), specifically, NABERS Energy and NABERS Water.

Energy modelling simulations undertaken during the design of the building indicate a potential performance more than 20 per cent better than the 5 star Green Star benchmark. An assessment of the water performance against NABERS also indicated that the development performs better than the 5 star benchmark.

The electrical and water sub-metering installed and connected to the Building Management System (BMS) monitors energy and water consumed by major end users in order to assess performance against these targets. In addition to the BMS, an EP&T EDGE Monitoring System has been installed to monitor and provide comprehensive data on the energy consumption of the building. Both the BMS and EDGE data can be accessed remotely.

To ensure that the building is operating as designed, the energy consumption targets are set based on these predicted ratings. As a minimum target, the energy/greenhouse and water targets are set at the 5 star NABERS level. This equates to maximum greenhouse emissions of 101 kg CO2/m2/year and maximum potable water consumption of 0.35 kL/m2.

As a result of the above initiatives, the following savings are expected:

• In excess of 65 per cent less potable water consumed compared - to all average building (an average building is based on a NABERS rating of 2.5)
• More than 60 per cent less greenhouse emissions associated - with energy use compared to an average building
• Peak base building electrical load that is reduced by 20 per - cent.

Future outlook

It is anticipated that water saving initiatives in The Gauge’s design will reduce potable water consumption by a further 30 per cent when compared with existing typical 5-star Green Star rated buildings, while the onsite gas-fired cogeneration system and energy consumption reduction initiatives will reduce greenhouse gas emissions by over 30 per cent when compared to typical 5-star Green Star buildings.

Lend Lease CEO Steve McCann said “One of our long term aspirations is for all buildings and communities we develop or manage on behalf of our investment partners to be independently rated to achieve green building status. Ultimately, we aspire to be zero net carbon, water and waste in the buildings we develop. The Gauge is an important step towards achieving that aim.”