The northern façade of the new Building and Construction Training Centre at the University of Ballarat’s SMB Campus is not only an eye-catching design, it also features high-tech construction materials. Covering 200 square metres, it is the largest contiguous vertical north-facing Building Integrated PV (BiPV) façade in Australia.
From the outside the 85 photovoltaic panels look like tinted glass, but they also generate renewable electricity. This electricity, converted from DC to AC through a bank of Fronius inverters, is used in the building or fed back in to the electricity grid. Supplied by Schott Solar through Going Solar, the panel glass is coated with thin films of transparent conductor amorphous silicon. Although thin film amorphous silicon is normally not transparent, this façade is made up of a semi-transparent version called ASI-THRU, where 10 per cent of the surface is free of silicon. This means people inside the building can see outside, but still enjoy privacy. The ASI-glass is double-glazed, providing excellent thermal properties and the ability to block solar radiation from entering the building. This has cut the air-conditioning plant size by 40 per cent and significantly reduced air-conditioning running costs. Avoiding and adapting to shade was the greatest challenge in the system design, as a small amount of shade can greatly affect power system production.Article continues below…
Distinguishing features of the project are the low profile framing and non-active-silicon glazed area, which minimise the impact of any horizontal bar of shade from the frame. Whilst vertical installation is sub-optimal for solar production, the vertical façade was simpler and cheaper for building design and construction. The effect on performance of unavoidable shade and vertical angle was minimised through the use of amorphous silicon technology, which performs better than crystalline solar panels in partial shade or indirect light.
Energy purchase and supply
The plant is expected to produce 7.3 MWh of electricity per annum. This energy is offset against the university’s consumption under its contract with its energy retailer. Real-time system performance can be viewed on a custom-built interpretive display in the entrance foyer.
The project is expected to save 10 tonnes per annum of greenhouse gas emissions from direct electricity generation. In addition, the high performance solar glass can be reasonably expected to save this amount again (or more) from the decreased air-conditioner load.