by Luke Kenny
There are a myriad of uses for elephant poo. Hot air ballooning is not currently one. Image by Henrikas Mackevicius from Pixabay.
Given that an elephant can produce as much as 150 kilograms of dung a day, zoos have recently begun exploring ways to harness that resource, as a means of reducing both their energy and waste disposal bills.
For nine years, Hellabrunn Zoo in Munich operated a biogas plant to anaerobically decompose the faeces of its vegetarian residents. Not only did this produce methane to power 5% of its electricity requirement, but the resultant heat from the decomposition process also heated the gorilla enclosure. The remaining “cake” was used as a fertiliser to increase the yield of food for the zoo animals.
Unfortunately the Hellabrunn Zoo announced the closure of the biogas plant in January 2016, citing high modernisation costs, though it also noted that the plant was no longer economically viable. However sad this may be, it does show the novel approaches that can be made in terms of closing energy loops, converting waste into energy or a valuable end product, in order to complete the production circle.
The baton has now been taken up by Toronto Zoo, who through a non-profit enterprise called ZooShare have tasked themselves to be North America's first zoo-biogas plant, with the conversion of the “zoo poo”, along with food waste from supermarkets, into electricity and fertiliser.
It should be said that the use of animal excrement as fuel is hardly a novel idea. Dry dung fuel has been burned across the world for millennia by many different cultures. It's like the answer has been right under our noses, or tails perhaps, because going back to elephants, one could be forgiven for getting confused, given the larger of its two tails sits on its face.
Interestingly, when one delves deeper into what comes out of the hind-parts of an elephant, one can find all sorts of treasure. Coffee beans can pop out, and some of the most expensive ones on the planet at that. Were you to now interrupt and suggest that the author is mixing up the largest land mammal on the planet, with a four kilogram civet (a cat-like mammal found across southeast Asia), then it is actually you who are mistaken and thinking of “kopi luwak”.
“Kopi luwak” coffee beans were initially collected from wild civet poo (scattered around the rainforests of Indonesia), and the semi-digested beans touted as having a distinct taste, with less acidity and increased smoothness.
Connoisseurs aren't all convinced that it actually enhances the taste, and more recently the industry has been marred by stories of beans produced from wild civets caught, caged and force-fed coffee cherries in order to meet global demand.
This meant a new opening for a novelty coffee - enter elephant dung coffee - with notes of 'chocolate/cacao, spice, (tobacco and leather), a hint of grass and red cherry.' The producer is the Black Ivory Coffee company, based in Thailand and promoting themselves as supporting elephant care-giving families. They sell their small harvest - a total of 150 kilograms in 2019 - for the staggering price of approximately $2000 per kilogram. If the caffeine didn't already wake you up, forking out that much might well do.
Several beer companies have jumped on board the “hathi howdah” (an elephant saddle to you and me), brewing up stouts using the gut-fermented beans. One, called “Un, Kono Kuro” (a play on the Japanese word for poo, unko) offered '…an initial bitterness that got washed over by a wave of sweetness’. The beer sold out within minutes on the company’s website.
The key to many elephant dung enterprises is actually the animal's rather inefficient digestive system. Despite a transit time of up to 24 hours, only about 40% of the original material is digested, leaving a sizeable deposit of useful material behind.
The highly fibrous nature of the waste lends itself to paper manufacture, the production of which can boost employment opportunities in less developed parts of the world, without the need for virgin wood pulp as a raw material.
If all of that has been a bit hard to digest, then I beg your pardon for not beginning with an aperitif, Indlovu gin from South Africa, and yes, you guessed it, it's infused with the undigested botanicals of hand-collected elephant dung.