The Global Change Institute at the University at Queensland (UQ) is piloting a number of innovative sustainable solutions in its quest for 6 star Green Star Education Design and As-Built ratings and its aim to operate as a carbon neutral, net zero energy working and learning environment.
Designed by HASSELL in collaboration with an engineering team which includes Bligh Tanner, Arup and Medland Metropolis, the Global Change Institute is one of the first buildings to be registered for The Living Building Challenge and will consume 30 per cent the energy of the Green Building Council of Australia benchmark education project.
Global Change Institute director, professor Ove Hoegh-Guldberg, said it was the latest example of UQ's commitment to improving sustainability outcomes across the world.
"It's the ideal home for the Institute's game-changing research, ideas and evidence-based advice for addressing the challenges of global change," Hoegh-Guldberg said. "It will be naturally ventilated for most of the year whilst a super low energy comfort conditioning mode ensures occupant comfort in even the hottest and most humid Brisbane days. The building generates and stores all its own power on-site through renewable solar energy sources that are pollution-free. All excess power will be delivered back to the national grid."
The Global Change Institute site is the first building to include structural use of cement-free geopolymer precast concrete, a material that could revolutionise low carbon construction and which significantly reduces the building’s carbon footprint. It saves up to eight tonnes of carbon dioxide per 10 tonnes of concrete.
The removal of cement hugely improved the product's sustainability, as it is the one material which has the highest contribution in terms of embodied energy and CO2 emissions. The replacement of cement with a key material, fly ash, involves the use of waste products from coal fired power stations. The geopolymer panels also have faster curing times which could allow permit re-use of formwork and lower production costs, as well as higher fire and chemical resistance.
"We have taken environmentally sustainable design a step further and precast world-first geopolymer concrete floor panels which, with significantly lower embodied energy, helps to reduce the building's carbon footprint. Prior to the GCI project, industry experts considered that practical application in such a significant way would be many years away from happening. We're pleased our application expedited this for everyone's benefit,” said project leader and director Rod Bligh of Bligh Tanner Consulting Engineers.
An integrated approach between the architects and the whole engineering team has been integral to the successful incorporation of a raft of cutting edge sustainability initiatives.
“The architectural team, engineering team and sustainability team were all actively engaged in the research. There was a high degree of investigation and collaboration on the opportunities that would work technically,” said HASSELL principal Mark Roehrs, who led the GCI project design team.
The building also features an operable sun shading system that tracks the sun and protects the glass louvres which optimise natural ventilation for 88 per cent of the year. The air flows across occupied spaces to the central atrium which acts as the building's lungs, discharging warm air through its thermal chimney. The thermal mass of the building is cooled with chilled water flushed through the exposed sculptural Geopolymer precast floor panels to optimise its performance in open and closed ventilation modes.
In closed ventilation mode, air is pre-cooled through a labyrinth before an innovative 'free-energy' comfort conditioning system cools and dehumidifies the air using a heat recovery sensible wheel and dessicant thermal wheel. Moisture is expelled from the air via a phase change material gleaned from 90-degree Celsius hot water generated in an evacuated solar tube water heating system.
The translucent ETFE atrium roof allows natural light into the interior while insulating from the sun's heat. Optimal natural lighting is supported by environmentally-friendly LED lighting. Rainwater storage of 60,000 litres services the hydronic cooling system, kitchen and shower.
"The building is able to act as a live research site, with the building systems and occupants used to assess comfort conditions in low-energy buildings for the sub-tropics,” Roehrs said.