Optimisation of Rural Biomass Waste to Energy Systems Rachel Namuli

Abstract

 Biomass waste to energy conversion systems were traditionally installed on rural farms to manage manure disposal and mitigate odour. These systems provide heating and electricity and are increasingly viewed as sources of revenue. Poorly operated or sized systems will not realise revenue. For farms that would like to install such systems, there is no tool available that optimises the systems prior to determination of their commercial viability. As such, there is a need to optimise these systems to determine the threshold herd size for commercially viability, and their maximum revenue. The associated optimisation problem is non-linear, non-convex and very difficult. Consequently, its solution is explored with a metaheuristic. The Tabu Search metaheuristic was adapted to solve this problem by: multi-period and diversification strategies that effectively search the solution space, handling of constraints using different strategies for searching feasible regions, with incursions into infeasible regions, and evaluation of a multi-objective function exploiting an approximation of the Pareto front. This dissertation is on research done to determine the threshold herd size for commercial viability of the biomass waste to energy conversion systems, and the maximum revenue from these systems.