Dry dung fuel

[4] "Dung cakes", made from the by-products of animal husbandry, are traditionally used as fuel in India for cooking food in a domestic hearth called a Chulha.

This biofuel has been used primarily for two reasons: for easy disposal of cow dung and as easily available and cheap fuel.

[17] In Equatorial Guinea archaeological evidence has been found of the practice[18] and biblical records indicate animal and human dung were used as fuel.

[20] Dung cakes are generally a higher emission fuel, with the combustion of cow dung cake samples collected from the Delhi area of India releasing around four times more volatile organic compounds than fuel wood samples.

[21] The volatile organic compounds released from cow dung cake combustion have been shown to be significantly more reactive with the hydroxyl radical, with the gases released from the combustion of cow dung cake samples collected from Delhi in India around 120 times more reactive with the hydroxyl radical than the emissions from liquefied petroleum gas.