Quantification of bio-wastes availability for bioenergy production in Zimbabwe

Abstract

The energy demands in Zimbabwe have drastically increased due to the improvement of the country`s economy. To supply the electricity, Zimbabwe imports most of its energy but the demands are yet to be fulfilled. Bio-waste provide an alternative energy source, however, it has not been fully explored and their quantities are currently unknown. Therefore, this study assessed the bio-wastes availability for bioenergy generation in Zimbabwe. Yield data on biomasses were obtained from the international databases of Food and Agricultural Organization which was validated by the data obtained from Zimbabwean Ministry of Lands and Agriculture as well as from research institutes. The information compiled included biomass from agriculture, municipal solid waste, livestock's dung and municipal sewage sludge. Forests were not considered due to the government prohibition of forests exploitations. The results showed that a total of 49 Gtons of bio-wastes are sustainably available producing a total of 539 PJ of energy which constitute ∼42.3% of the total energy required in Zimbabwe. Among the available bio-wastes, crop residues with ∼48 Gtons produce the largest amount of energy ∼502 PJ followed by animal dung ∼36.2 PJ, then MSW ∼9.1 TJ and lastly by MSS ∼0.8 TJ. Assessment of the bio-waste availability is vital for bio-energy technology to be used sustainably implemented in Zimbabwe.

Keywords

• Bio-wastes quantities
• Energy potential
• Mathematical modelling
• Bioenergy
• Zimbabwe