GIY Clonakilty notes by Riley Liao
The Solar CITIES Blue Flame tour held a community build of an IBC biodigester at the Clonakilty Community Garden on July 8. Thomas H. Culhane, co-founder of Solar CITIES and an expert in small-scale energy production, led the demonstration and shared his insights into the possibilities of the home-based biodigester.
A number of people attended, including families from the Clonakilty Lodge Direct Provision Centre, The Clonakilty Community Garden and GIY (Grow It Yourself) Clonakilty. Everyone had a hand in putting together the biodigester and it started to warm up within a few hours of completion.
The Solar CITIES IBC (International Bulk Container) biodigestor’s design is as simple as it can get. It’s essentially a big stomach that has two large pipes for input at the top that go all the way to the base and a hosepipe in the middle for collecting gas.
Assembling the biodigester involved ‘burning’, an exciting process where a 4in metal cylinder was heated up and pushed through the top of the tank to make a hole for the input pipe. The IBC tank was then wrapped in black plastic to prevent algae from growing.
Post-assembly, the tank’s 1000litre capacity was filled with water, and the task of shovelling fresh manure began, seeding the tank’s bacteria. The biodigester runs anaerobically (without oxygen). In a few weeks the bacteria will have multiplied enough for the Clonakilty Community Garden to start the process of feeding in weeds and food waste.
While talking about the origins of the IBC biodigester, Thomas told a story detailing his quest for a sustainable energy source during his travels to places such as Iraq, Egypt and India. The Holy Grail turned out to be a ‘burping’ bucket of liquid compost on the roof of an Indian household. There he also learned the key of feeding a biodigester food waste instead of manure — ‘it’s a stomach not a colon’.
This fire-breathing dragon is the new king of DIY projects. Once running, a daily bucket of food waste produces enough methane gas for around two hours of cooking. At the same time, the biodigestor processes organic matter faster than a compost heap without losing any nutrients. The only maintenance it requires is a balanced diet.
For more information on biodigesters visit www.solarcities.eu.
Come and get growing at the new Clonakilty Community Garden between 11am and 1pm every Saturday, behind Deasy’s carpark. GIY Clonakilty’s first meeting after the summer break will be at 8pm on Monday, September 14 in O’Donovan’s Hotel. Con McLoughlin from Lettercollum Kitchen Project will give a Nutritional Cooking demonstration.