Food waste could provide London with new gas supply

By Tierney Smith

Anaerobic Digestion usually takes place at a much larger scale in the UK and Europe (Source: eXtension Ag Energy/flickr)

Imagine a technology which could sit at the heart of a community, and would not only reduce the problem of excess waste, but would also help to generate heating, electricity and provide a fertiliser for your growing needs.

That is the vision of the Creative Health Lab, a social enterprise based in North London, as they work towards developing a small scale, community Anaerobic Digestion (AD) project to be replicated across the country.

AD is similar to composting, except without oxygen. It is a process where plant and animal material – including food waste, manure, sewage and green waste is degraded by natural organisms in the absence of air.

The result is a biogas, made up of carbon dioxide and methane that can be used to generate heat and electricity and a digestate that can be used as a fertiliser.

While the process can occur naturally – for example in swamps – it is re-created in a sealed vessel, or vessels, and is often found in the UK on farms, where waste is in abundance and there is a need for both the biogas and the fertiliser products.

AD projects in the UK at present are generally large, industrial scale technologies, but Creative Health Lab want to see the technology scaled down to a more local level.

“I suppose the innovative part of what we are doing is developing it at pretty much micro-scale,” Rokiah Yaman from the Creative Health Lab told RTCC.

“We are talking about starting off at one cubic meter and then building up from there and creating some sort of modular system that can apply to a range of locations in an urban environment.

“We’re looking at the possibility of siting them in places like universities where they have the space and a substantial amount of food waste,” she added.

“But we are thinking about other models as well. So it could be a digester sighted somewhere and then used by a variety of organisations. It could be used by schools, local businesses and there’s the possibility of some residential collections as well.”

The project LEAP project (the acronym stands for Local Energy Adventure Partnership) is currently looking at two North London sites where they can begin trialling the small-scale technology, which is already used widely in the developing world.

The process produces a biogas which can be used for heating and electricity and a fertiliser for farming (Source: muggers/flickr)

“The main barrier is not necessarily the technology itself, because there are many people who have built their own systems and made them work in their back gardens. I think the main barrier in the West is cost effectiveness,” Yaman said.

“Usually where you have small scale systems in the East the labour is cheap or almost non-existent because they get people to build it themselves and then maybe have an expert of oversee the process.”

LEAP will be exploring the potential of setting up a community eneterprise to give local young people employment opportunities. They will start off with a team of apprentices who will help help build and operate the test anaerobic digestion systems with the help of AD experts and engineering students from Imperial College.

“In order to build it into an economical, sustainable model and in order to roll it out or have it as a social enterprise we need to do a proper business plan and make sure we could cover all of the costs that would be involved,” she said.

While the first year of the three-year project will be about developing technologies, trying out new ideas and testing different size models, the second and third year will see the social enterprise expand and the technology developed into something which is economically sustainable and technologically viable.

The project is not all about developing a new technology though. Creative Health Lab’s proposals include an extensive education programme.

Having built up links with schools and universities they hope to get eco-groups involved at the research level – accessing how much waste schools have and how much energy this could produce – and to create educational kits for wider distribution.

As the project has developed it has also grown and now the sites currently proposed for the technologies could potentially develop further into renewable hubs, researching a variety of new technologies.

Once fully operational in North London, Yaman says the open-sourced nature of the design means they could see it replicated up and down the country.

“One of our partners is the Community Composting Network and they’re ethos is very much around keeping all findings open sourced. So any community group, in fact anyone will be able to source the information which we came up with in terms of the operational side of AD and anyone will be able to build their own digester.”

Contact the author at [email protected] or @rtcc_tierney

VIDEO: Rokiah Yaman describes more about the project and the aims of installing small scale AD into the local community.

 

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