A Victoria University engineering lecturer and his students have designed a solar-powered desalination plant at Brisbane's Mount Coot-tha Botanic Gardens.
Dr Eric Peterson and fourth-year students in the School of Engineering and Science designed and help build the $500,000 project, in collaboration with the University of Queensland Centre for Marine Studies, and VU's Institute of Sustainability and Innovation.
As a further challenge, Dr Peterson and his team are working towards achieving zero waste from the project by piping the salty brine that is normally discharged as waste, through a series of terraced ponds propagated with local salt-loving marsh plants.
The saltwater plants can in turn be harvested and incorporated into livestock fodder in a complete recycling process.
"The innovative use of marine plants as a bio-filter for salt has been used for a number of different applications, but never in conjunction with small scale desalination plants," Dr Peterson said.
Operation started in the 60-hectare Gardens last year. The plant is driven by solar panels that pump brackish bore water from the Brisbane Aquifer - located some 80 metres beneath the Gardens - and press it through reverse osmosis membranes to strip out salt ions. The desalinated water is then shandied with nearby lake water to introduce minerals and nutrients that are necessary for garden irrigation.
The plant has the potential to generate about 64,000 litres of desalinated water a day. Once fully operational in the coming months, the project is expected to produce 10 million litres of recycled water a year - or about one-quarter of the Garden's requirements - using solar power by day, and inexpensive, off-peak electricity by night.
During extreme drought conditions in 2005 to 2007, staff needed to truck in up to 200,000 litres of recycled water a week to maintain the Gardens.
Jason Chisari, 23, who graduated from VU last year, helped with the project as part of his mechanical engineering degree.
"The challenge was to build a green desal plant with the potential for zero waste," he said. "This is exciting because it could be used as a model for similar irrigation systems in other nurseries or parks around Australia."
The Brisbane City Council and the Queensland Government funded the project, and the Botanic Gardens staff contributed specialist in-kind support.
Dr Eric Peterson is available for interview. Contact: Ph: (03) 9919 4859
A photograph of the solar-powered desalination plant is available on request
Media Contact: Ann Marie Angebrandt, Media Officer
Marketing and Communications Department, Victoria University
Ph: (03) 9919 5487