Back in 1960s, in the villages of Sindh, Pakistan, and even in some towns, it was a common sight to see village women making cow dung cakes, putting them on walls for drying. These women were expert in making cow dung cakes. The dried cakes were used as fuel for cooking food.

That scenario, which I still vividly remember, was just an another sight – a common way of life. Now, according to United Nation University report, probably released on 4 November 2015 (attached), biogas from human waste, safely obtained under controlled circumstances using innovative technologies, is a potential fuel source great enough in theory to generate electricity for up to 138 million households – the number of households in Indonesia, Brazil, and Ethiopia combined.

The report of UN University’s Canadian-based Institute for Water, Environment and Health estimates that biogas potentially available from human waste worldwide would have a value of up to US$ 9.5 billion in natural gas equivalent. And the residue, dried and charred, could produce 2 million tonnes of charcoal-equivalent fuel, curbing the destruction of trees.

While the UN University report talks of human waste, I can now realize the importance of cow dung cakes and, its potential use as a source of fuel. While gas connections have been provided in towns, the practice of using cow dung cakes still exists in villages. The report of UNU is worth reading.

F H Mughal