When safely obtained under controlled circumstances through innovative technologies, biogas from human waste serve as a potential fuel source; according to a report from UN University’s Canadian-based Institute for Water, Environment and Health, it could have a potential value of up to $9.5 billion in natural gas equivalent. And dried and charred residue could produce some 2 million tones of charcoal-equivalent fuel, allowing us to curb the destruction of trees. Experts say that the large energy value would prove small in comparison to that of the global and environmental benefits that would come from safely treating human waste in low-resource settings.
The report uses average waste volume statistics, high and low assumptions for the percentage of concentrated combustible solids contains, its conversion into biogas and charcoal-like fuel and their thermal equivalents to calculate the potential energy value of human waste. Biogas, around 60% methane by volume, is generated through the bacterial breakdown of any organic matter in an oxygen-free system. And dried and charred fecal sludge has energy content similar to coal and charcoal. UN figures reveal that 2.4 billion people don’t have access to improved sanitation facilities, and almost 1 billion people (60% of whom are in India) don’t use toilets at all. If the waste of only those practicing open defecation was targeted, then the financial value of potential biogas would exceed $200 million every year, reaching even as high as $376 million. The energy value would equal that of the fuel necessary to generate electricity for 10 to 18 million local households. And processing residual fecal sludge would yield the equivalent of 4.8 to 8.5 million tons of charcoal.
Recycling body waste is nothing new; both human and animal waste is already used as fertilizer with guidelines to ensure its safe use. Mismanagement of human waste, especially in less developed countries, has a long track record of creating misery and poverty. A simple, cost-effective to manage that waste could change the economic approach to waste management, helping to reduce sanitation problems. If you’d like to learn more about this study, then click here!