Sylvia Pfeifer in the Financial Times reports that Poundbury, the Dorset town designed by the Prince of Wales, is pioneering the use of micro-organisms to break down organic waste from chocolate, potato and cereal factories, converting it into methane-rich biogas – a process called anaerobic digestion.
The gas can be burnt to generate electricity and heat to serve Poundbury and the surplus is fed into the national grid. At peak capacity the plant will provide gas for about 4,000 homes during the winter and up to 56,000 homes during the summer.
The newbuild houses in Poundbury all have photovoltaic tiles and ground-heat recovery systems as standard. Social housing has been well integrated and the electric bus transport system is appreciated.
England and Wales produce about 300m tonnes of waste a year, according to the Environment Agency. The EU’s Waste Framework Directive calls for 50% of household waste to be recycled by 2020 and EU targets have been set to reduce the amount of biodegradable waste sent to landfill, with severe penalties for failure.
Investors and corporates are now recognising that waste – from food to municipal sewage – has a role to play in the energy sector.
There are a range of methods to generate energy from waste; alternatives to incineration include landfill gas power, gasification and anaerobic digestion.
Some question whether the new technologies can reach an industrial scale, but others advocate smaller decentralised systems as being more resilient and employment intensive.