At the end of 2018, Australia passed the milestone of two million households with rooftop solar panels, according to the Australian Renewable Energy Agency (ARENA). As new products and materials come onto the market, roof-mounted panels are only one of the options of turning a building into an electricity-generating powerhouse.
One of the major areas of innovation is Building Integrated Photovoltaics (BiPV). Products in this space include balustrades, window glazing, skylights and canopies that incorporate thin-film solar cells within the product.
General manager of Environmental Technology Solutions [ETS] Matt Joyce tells Jobsite that there is a growing demand for BiPV products.
Ratings remain 0ne of the push-factors driving projects towards greener solutions. Such improvements can help projects looking to achieve a Green Star rating from the Green Building Council of Australia or a high energy-efficiency rating under the NABERS scheme.
Joyce’s company has supplied Onxy solar BiPV balustrade products, canopy glazing and façade glazing for a wide array of projects, ranging from multi-residential developments to commercial buildings, to bus stops and education buildings.
ETS has also recently become the sole distributor in Australia for Hanergy BiPV products—the manufacturer who suppliedNASA with the flexible thin-film solar panels used on the Mars Rover.
According to Joyce, the return on investment of the Hanergy BiPv products is making people “take notice” of the materials. The products include glazing for curtain walls, both transparent and opaque products suitable for cladding, window glazing units, flexi panels and skylights.
One of the major benefits of the BiPv, Joyce said, is that it enables a building to collect solar-generated power from a greater area. At the same time, it frees up roof space, which can be then used for roof gardens, for instance.
What’s more, when opting for BiPv solutions, the roof doesn’t need to be engineered so that it can take the weight of a traditional solar array. Joyce explains a recent car park project he worked on would have required a structure capable of holding 25 tonnes of traditional crystalline PV panels. However, by switching to a thin film BiPV product, it only needed to engineer the rooftop for a three to four-tonne load, thus allowing the project to downsize the structural requirements.
The BiPV units also generate power in lower-light conditions including overcast days, areas that are shaded and other cases where orientation may not be optimum for traditional panels. The U-rating of the glazed products also reduces heat gain inside the building without reducing natural lighting substantially.
Joyce says the best time for a developer or builder to consider using BiPV is at the initial design stage before the Development Application is lodged. In a multi-residential project at Northcote, the plan to utilise BiPV balustrading and the benefit that had for compliance with Section J of the National Construction Code resulted in the consent authority granting the project proponent an entire added level.
This also means the insulation and energy efficiency gains can be factored into the sizing of HVAC and electrical systems, potentially saving on these project elements.
Joyce believes the use of BiPV products will “become standard practice in the near future.”
One of the features of many of the leading-edge solar products is they perform multiple functions. Unlike solar PV panels which generally have just one primary function—creating energy—a product like Tractile’s solar rooftiles has multiple purposes.
Designed in Australia, the tiles are cyclone-rated, impact-resistant roofing tiles. They also heat water for the building hot water supply, provide insulation, and generate solar energy. The product was used for University of Wollongong’s Desert Rose House, which placed second in the Solar Decathalon in Dubai in 2018.
The CSIRO has been leading the development of a range of flexible solar cell products including organic photovoltaics and perovskite photovoltaics.
The flexible, semi-transparent PV is created through printing solar cells as a thin-film solar module. It can then be embedded into or added to a wide variety of substrates.
A prototype canopy utilising the thin film flexible solar has already been installed at Melbourne Zoo. CSIRO says the technology could be used to design products like tents that charge devices while camping, temporary power generation arrays for remote sites or emergency situations, tensile architecture applications such as stadium roofing, sails for boats, blinds and curtains—possibly even clothing and consumer packaging!
Another area seeing some serious push for the uptake of innovative new technologies is solar heating and cooling. ARENA is supporting CSIRO in partnership with the Australian Institute of Refrigeration Air Conditioning and Heating (AIRAH) and VIPAC to promote the use of solar heating and cooling technologies in Australian buildings—the so-called PUSCH initiative.
The PUSCH initiative involves assisting the building industry with training, case studies and knowledge resources.
There have been a number of exemplar projects completed, including the installation of solar-thermal cooling at Stockland’s Wendouree Shopping Centre in Ballarat, Victoria. Solar HVAC is regarded as particularly valuable for large retail buildings due to their high energy demand for heating and cooling stemming from large internal building areas, and extensive roof areas.