Biochar yield is defined as the final weight of the charred fuel as a percentage of the initial fuel mass. The biochar yields from cow dung combustion for five different burn time are presented in Table 1, this value includes the ash content that was found through testing to be 24%. This value is higher than commercially available biochars; however, this is because the ash content of cow dung is naturally higher than that of biochars produced from woody biomass. It is evident that as the burn time increases biochar yield decreases. There is a direct compromise between the amount of biochar produced and the length of cooking time per fuel canister. This result was expected, considering that char oxidization begins when the pyrolytic flame front reaches the bottom of the fuel chamber. With an ash content of 24%, a burn time greater than 40 minutes resulted in a biochar yield consisting entirely of ash, which can not be used as a soil enhancer. From [16], emissions of carbon monoxide were found to significantly increase after 20-25 minutes for these tests. Therefore, extending the burn time is not only detrimental to the amount of soil enhancing biochar produced but also to the health of the stove user.