The Economic and Bio-Energy Production Potential of South Australian Food Waste Using Anaerobic Digestion

Australia is one of the highest food waste generating countries in the world per head of population with over 7.3 million tonnes of food waste generated in Australia in 2008.Anaerobic digestion (AD) is a promising and environmentally sustainable organic waste treatment technology which digests organic waste into a stabilise residue and generate biogas, which can be used to produce energy. Despite large-scale application of AD in the USA and Europe, AD has not been applied widely in Australia. This paper investigates the challenges and opportunities of managing organic waste in South Australia using AD. Following a comprehensive literature review of AD technologies in relation to challenges, barriers and scope of implication in the global context, the study forecast the bio-energy production potential in South Australia using AD. This paper finds that the small AD plant could generate 39kWh from around 589 tonnes of food waste annually. The study also forecast the bio-energy potential by 2021 and if 15% of South Australia's food waste (of year 2021) were treated with AD, a 256kWh energy could be generated. The addition of poultry waste would dramatically increase the proposed plant size up to 3556kWh. This would be a large energy plant that would be a considerable contributor to the SA power grid, provide a level of SA energy security. The payback time for all plant sizes is between 2.5-3.5 years