Characterization of densified bamboo as an alternative to unsustainable woody biomass cooking energy sources

Bamboo-based cooking fuel is an alternative to the unsustainable or “black” firewood/charcoal that is currently used by over 95% of the East African population. The use of “black” energy sources has undesirable environmental and livelihood consequences, such as forest cover loss and related climate change, energy insecurity and poor health for kitchen workers who breathe smoke-filled kitchen air. Bamboo is attractive for several reasons, the main one being that it can mature in a short period of 4-5 years; it is tag-harvested, meaning that the stump is composed of poles (culms) of different age and only the mature ones are harvested, thus avoiding replanting; and it can grow in marginal lands. The challenge for the adoption of bamboo as an energy source has been that it releases its energy too fast, which is inconsistent with local cooking habits. We sought to devise a way in which bamboo firewood and/or charcoal can be configured to cook like the preferred hardwood-derived firewood or charcoal. The solution adopted was to crush and densify the bamboo particles, forming non-carbonized briquettes (branded as YAZINI firewood) followed by carbonizing to produce charcoal (branded as YAZINI charcoal). Here, we characterize YAZINI with respect to its cooking performance under controlled environments as well as in the hands of target users. Six bamboo species were screened for their Fuel Value Index, and Bambusa vulgaris and Dendrocalamus asper were selected for further study. The validity of the proof-of-concept was tested by using a modified water-boil test and showing that YAZINI released it energy in a manner indistinguishable from that of hardwood-derived firewood/charcoal. To demonstrate potential for adoption, the water-boil test results were further confirmed in the hands of target users through usability studies. The usability of YAZINI firewood and charcoal were scored (on a Likert scale) between 4 (above average) and 5 (high) and 3 (average) and 4 (above average), respectively. The results indicate that YAZINI firewood and charcoal are viable alternatives to black firewood and charcoal in terms of cooking characteristics. However, further studies (pilot-scale) are needed to confirm the cooking characteristics with a wider target audience and most importantly to demonstrate economic viability, as well as kitchen air quality improvement.