It’s time to talk anaerobic digestion and humanitarian aid

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There are numerous innovative renewable energy technologies currently being developed for the most challenging humanitarian work. Printable solar panels, green streetlights that fight off mosquitoes and solar balloons to name a few. These inventions will be incredibly valuable when providing humanitarian relief, but many are still stuck in research and development phases and will be extremely expensive to deliver.

What those inventions don’t offer is an effective circular economy. For isolated, rural, less wealthy populations and those requiring humanitarian aid, the benefits of an effective circular economy are even more direct, concrete and obvious than for a Western urban population. Anaerobic digestion fits perfectly in such a circular economy for several reasons, in part thanks to the energy independence it induces.

From the outset, anaerobic digestion contributes obviously to a circular economy because while on one hand it produces biogas for cooking, heating, and even lighting, it also generates digestate which can fertilise future crops,  and allows reducing the waste of organics that would otherwise be discarded (food waste, livestock manure, human sewage etc). Thus, it fully exploits the biological and energy potential of unused organics as well as providing a simple method of containment and sanitation of problematic wastes that might otherwise cause more environmental problems.   Moreover, as anaerobic digestion is a natural process relatively easy to reproduce at any scale, the implementation of small anaerobic digesters is possible without requiring huge investments such as those associated for example with the installation of an electricity or gas grid to rally an isolated community. Biogas is an accessible, viable, and sustainable humanitarian solution.

QUBE’s first digester was designed after we were approached by the UK Ministry of Defence (MOD) who requested a solution to deal with food and sewage waste generated from their forward operating bases in Basra. As a result of this feasibility, our team developed a modular micro AD system which would be able to be easily transported into difficult to reach places and be run ‘off grid’, without the need for any supporting infrastructure.

Our most recent humanitarian aid work took us to The Philippines where we installed our dryQUBE. Rice is the world’s number one food crop there are 200 million small scale rice farmers worldwide. Globally each year 300 million tonnes of rice straw is burnt as waste or left to rot, this produces 8.4 giga tonnes of carbon a year. Rice straw has a massive GHG emissions and burning it causes chronic pollution.

Philippine’s hot climate makes it an ideal condition for developing dry AD, as no energy is spent heating up the leachate to spray onto the feedstock, in comparison to the heating requirements of other types of digesters in colder climates. DryQUBE enables locals to harvest both the straw and the rice and adds value to the biogas produced through AD by making various products for cooking, running generators and upgrading as a fuel for vehicles. Additionally, it creates a rich fertiliser with the spent rice straw that can be used for the next rice crop.

AD may not be the most glamorous solution for humanitarian relief, but it does offer a long term and affordable solution that turns waste into an asset. AD is versatile, easy to set up and is a global problem-solver. It’s potential shouldn't be ignored.  

Jo Clayton