A recent industry stakeholder conference in Sydney shed new light on where building materials and technologies could be heading in the future.
The Sustainable Built Environment 2016: International High-Performance Built Environment Conference gathered academics, researchers and all sorts of AEC professionals at Sydney’s Maritime Museum over two day to discuss, brainstorm and ultimately carve-out an improved and more-sustainable trajectory for Australia’s built environment.
While the majority of the big keynotes and lectures were focussed on macro challenges like planning policy and infrastructure spending, there was one break out session that focussed on smaller research projects exploring the viability and feasibility of new architectural building materials and manufacturing methods.
It was titled High Performance Materials and Emerging Technologies and was chaired by Gabriele Masera of the Polytecnic University of Milan who also presented two of his own research projects on the day. Masera was joined by six other academics from around the world who presented their findings from a variety of investigations into new and potentially game-changing building materials and technologies.
Here are two of the projects being developed in Australia:
ALGAE BIOREACTOR FACADES
UTS Associate Professor of the Built Environment, Sara Wilkinson presented the findings from her joint-exploration into the potential for using algae as a building material in Australia. Wilkinson and co-researchers, architect Paul Stoller and marine biologist Peter Ralph, have been looking at ways in which algae can be used on facades as an energy source and shading device for buildings.
The idea, said Wilkinson, grew from a similar project in Hamburg, designed by Arup and Austria-based Splitterwerk Architects, which is a fully functioning algae-powered building. BIQ House is clad in a number of bioreactor façade panels or 'pools' which have microalgae growing inside. The algae grows in bright sunlight, providing additional shading, and also produces biomass and captures solar thermal heat, both of which can be harvested and converted into useable energy for the building.
Currently, BIQ has 200sqm of algae façade which through conversion of biomass into biogas can generate a net energy gain of approx. 4,500 kWh per year.
Wilkinson and her team hosted a Living Algae Building Forum in July to gauge the interest of the industry in supporting the development of a similar system in Australia and to discover the major barriers to its uptake.
Despite the associated costs and relatively unknown viability of the project, Wilkinson and team have secured funding to develop a prototype façade panel and have a number of big industry stakeholders on board to develop it, including Arup, Lendlease and Steensen Varming engineers as well as G-James window manufactures and Viridian glass.
COMPOSITE PHASE CHANGE MATERIAL CONCRETE
Phase Change Material (PCM) is not an entirely new concept and we’ve seen it used as insulation and in plasterboard and ceiling panels in Australia. But new research from Swinburne University PHD Candidate, Ramakrishnan Sayanthanmight demonstraes how PCM can be injected into concrete to significantly improves its thermal inertia and thermal energy storage at a lower density while maintaining its compressive strength to acceptable measures.
In his research, Sayanthanmight developed a new thermal energy storage composite which uses the commonly used paraffin wax as a PCM in a different way. On its own, the paraffin was found to leak severely when it was integrated in cementitious composites so Sayanthanmight created a protective coating of hydrophobic coated expanded perlite (EPO) which wraps the paraffin and stops leakage entirely.
He then studied the structural and thermal behaviour of a number of test concrete panels containing different ratios of PCM versus aggregate and came to the conclusion that substituting 60 per cent of aggregate with PCM in a concrete mix will significantly improve its thermal storage while maintaining a compressive strength (25 MPa at 28 days) that is acceptable for many applications.
Five test panels were used, each with a varying ratio of aggregate and PCM beginning with no PCM (NC) all the way to 80%PCM/20% aggregate (TESC-80). The results show that substituting 60 per cent aggregate for PCM (TESC-60) maintains an acceptable compressive strength for many common concrete applications.
Arguably the most significant finding from the research however is how the injection of composite PCM affects the density of concrete. Sayanthanmight’s studies show that the density of the test subjects were reduced in conjunction with increased levels of composite PCM. This could be a significant finding as it provides a way to increase the thermal energy storage of lightweight concrete even beyond the capacity of a denser subject.