Both installations, along the Calder Highway and at the University of Ballarat, were undertaken by Going Solar and use Schott Solar PV panels.

Solar noisewall protects and powers

The Calder Highway installation is quite a unique project. Near the Bulla Road overpass, the long yellow wall that separates the freeway from North Essendon is topped with a crown of glass which blocks noise and doubles as a small power station with a peak power output of 24 kW.

The installation heightens the wall by 1 m for the next 500 m and features a total of 210 solar panels, each 2.3 m long and weighing 106 kg.

The 17 mm thickness of the panels, which includes two 6 mm layers of heat-strengthened glass, ensures their noise abatement qualities.

The Tullamarine-Calder Interchange Alliance, comprised of VicRoads, Baulderstone Hornibrook and Parsons Brinckerhoff, was responsible for the upgrade of the Tullamarine Calder Interchange, and pioneered the application of glass laminate solar modules for both renewable electricity generation and noise abatement.

While conventional solar panels have been used on noise barriers in Europe and North America, this system is believed to be the first where the solar module is an integrated part of the noise barrier.

Inside the outer glass layers of each module are four sub-modules of amorphous silicone thin-film tandem cells on a glass substrate contained within PVB layers. That allows each of the panels to generate 141 W at their peak, stabilising at 116 W in the long term.

The backs of the panels, facing the suburbs, are light in colour and partially reflect the sky, making for a less intrusive presence in the landscape.

The Schott Solar ASI-OPAK 4 L panels can generate enough electricity to power three small homes and offset almost 30 tonnes of carbon dioxide per year. The power is fed into the electricity grid.

The installation of this system was financially supported by Sustainablility Victoria through its Renewable Energy Support Fund.

High-tech solar façade for Ballarat

The northern façade of the University of Ballarat’s new Building and Construction Training Centre doesn’t just look good – it’s also contributing to sustainability by generating solar powered electricity.

Featuring state-of-the-art construction materials, the row of 85 large glass panels looks like tinted glass from the outside, but a closer look reveals some extraordinary technical capabilities. For a start, this glass generates clean electricity: approximately 7.3 MWh a year, and saves some 10.2 tonnes of carbon dioxide annually.

The glass is coated with thin films of transparent conductor, amorphous silicone (less than one thousandth of a millimetre thick), back contact and encapsulating material, which give the unit its photovoltaic properties. The process by which this is done is highly sophisticated and fully automated.

From the inside, a couple of other features become apparent. While thin-film amorphous silicone is normally not transparent, this façade is made up of a semi-transparent version called ASI-THRU, whereby 10 per cent of the surface is left free of silicone. This means that people inside the building can see outside, and yet also have privacy.

With the sun shining onto the façade, it is amazing how much energy is filtered out from entering the building. When added to the fact that the glass units are also double-glazed, it becomes clear how effectively that portion of the building is insulated. As a result of these thermal effects, the capacity of the building’s air-conditioning plant has been reduced by 40 per cent.

The clean power generated by the 200 sq m glass façade is converted from DC to AC through a bank of inverters and is used in the building or can be fed back into the power grid.

Great care was taken by installers Going Solar, architects McIldowie Partners and builders H. Troon in the design and construction of the façade to minimise shading, as any shade can badly affect the performance of these building-integrated photovoltaics. Fortunately amorphous silicone performs better under high-temperature or low-light conditions (such as during an overcast day) than the more common roof-top crystalline solar panels. How well the system is working can be seen on a custom-built display unit in the building’s entrance foyer.

This novel installation also achieves a major first for Ballarat: it is the largest installation of semi-transparent photovoltaic glass in Australia. It also recently took out the BCSE award for excellence in the design and installation of grid-connected solar power systems, presented at the 2007 ATRAA Conference and Exhibition.

The award recognises the excellence in system integration, compliance with highest standards and practice, compelling aesthetics and innovative design evident in this installation.