AD not 'absolute solution' for food waste in cities
Anaerobic digestion is not a silver bullet for dealing with urban food waste and must form part of a wider treatment strategy in the context of smarter city thinking.
That is the view of leading waste contractor Veolia Environmental Services who has published its third waste manifesto Making sustainable cities a reality which examines the key resource issues faced by businesses, local authorities and communities in urban environments.
Veolia argues that while anaerobic digestion "should be encouraged" for its energy generating potential, other treatment channels for food waste such as in-vessel composting must not be overlooked if the carbon economics around logistics and infrastructure stack up.
"Make no mistake, as a 'one size fits all' solution, anaerobic digestion doesn't deliver a comprehensive waste management solution for sustainable cities," the manifesto states.
The company is calling on the Government to drive greater uptake of food waste collection schemes, arguing that if just half of the seven million tonnes of food waste arisings each year in the UK were recovered it could generate 700,000 MWh of electricity - enough to power 140,000 homes.
"We believe that collecting food waste should be part of every city's waste management mix," the manifesto states.
The document also presses the case for rolling out more mixed plastics collections, and argues that capacity needs to be built into collection vehicles to ensure there is room for the material.
"The challenge with recycling plastic products is that they take up more room in the recycling bin than other materials of the same weight. But that shouldn't be an excuse ... it simply means that collecting mixed plastics needs to be pre-planned."
Veolia claims that if every council in the UK adopted mixed plastic recycling it would save over 300,000 tonnes of CO2 emissions each year.
Commenting on the manifesto, chief executive Estelle Brachlianoff said that business and council leaders both needed to "raise the bar" in understanding how to turn more of their waste into a resource.
"This isn't a short journey, but all these goals are within reach," she argued.
The debate around sustainable cities is gathering momentum - last month saw the official opening of The Crystal, the world's largest showcase dedicated to greening future cities.
Built by Siemens, the £30m glass-clad structure will serve as a technology innovation hub and urban dialogue platform to drive the growth of sustainable cities through partnerships, research and collaboration.