Tamar Energy chief executive Alan Lovell has spoken of the company’s plans to build the UK’s first anaerobic digestion (AD) plant capable of taking combined food and garden waste.
Lovell said Tamar Energy was planning the so-called dry AD facility in Greenwich to make full use of a wealth of commingled food waste, which cannot be used in ordinary AD.
“The significance of dry AD is that it can take commingled waste [food and garden waste combined],” he said. “That’s an interesting area because there is a lot of commingled waste out there - most of which goes to composting or towards the landfill.”
Being able to derive energy from commingled food waste in an economical way was attractive, said Lovell, as food waste will always have contamination.
The Royal Borough of Greenwich currently collects about 20,000 tonnes of food and garden waste from residents each year. This is expected to rise significantly over the next five years as more homes are built in the borough.
The new plant would enable a greater proportion of garden and food waste to be processed and ensure unavoidable residual waste is treated as a renewable energy source. Its capacity would be 42,000 tonnes per annum, with an expected throughput of 36,000tpa.
The Borough has made a commitment to provide between 18-25,000 tonnes every year for the facility.
Nearby residents and businesses were asked to contribute their views for the facility on industrial land at a site in Thamesmead on 1 June and the development of the facility is subject to an ongoing planning process.
The AD industry backed the proposal.
Charlotte Morton, chief executive of the Anaerobic Digestion and Biogas Association, said: “Anaerobic digestion is a hugely flexible technology in terms of the organic feedstocks it can process, the technology used, and what you can do with biogas and biofertiliser.
“Tamar Energy’s proposal for a dry AD plant to treat commingled food and green waste is another demonstration of this, and shows that no matter what their situation, councils can use AD to make the most of their organic waste resource with collection schemes that work for their residents and businesses.”
Dry AD explained
Commingled food and garden waste will be delivered to the Greenwich facility. The unloading of waste will be undertaken within air-locked buildings, and the AD process itself will take place in sealed tanks, in the absence of oxygen.
Heat generated by the processes will be collected and has the potential to provide heat to neighbouring buildings.
The site will offer an environmental improvement to current organic waste management practices, according to Tamar.
Dry AD plants are working in Germany, but similar processes have yet to be brought to the UK.