Most Australian food waste ends up in landfill. Rotting in the absence of oxygen produces methane, a potent greenhouse gas. While some facilities capture this “landfill gas” to produce energy, or burn it off to release carbon dioxide instead, it’s a major contributor to climate change. Valuable resources such as water and nutrients are also wasted.
Composting food waste is the most common alternative. In the presence of oxygen, microbes break down food and garden organics without producing methane. The product returns nutrients to farms and gardens. But composting facilities are limited and struggling to cope with contamination from plastic.
We analysed the capacity of three wastewater facilities in Sydney to process organic wastes from surrounding households and businesses.
