Edinburgh Napier University

  Biomass is one of the most versatile sustainable energy sources. This versatility allows utilization of different biomass feedstock using a verity of conversion techniques. Often, a biomass-to-bioenergy conversion method is selected depending on the application, end-use product, and the type of feedstock. In many applications such as residential energy supply, it is possible to select amongst various technologies. Although, there exist several challenges such as cost-effectiveness and sustainability that constrains bioenergy development. To this end, this research elaborates on the impacts of different conversion methods on techno-economic performance of bioenergy systems for residential energy supply. In this context, Organic Rankine Cycle based on direct combustion, and Dual Fluidized-Bed technology based on gasification were selected for that purpose. A techno-economic comparative analysis illustrates that the primary product of the system and fuel cost are the two most important factors in feasibility assessment. The negative impact of feedstock price was more severe on the Organic Rankine Cycle. For wood chips prices below 55$/t, Organic Rankine Cycle could be the better option due to lower capital and maintenance costs. In contrast, Dual Fluidized-Bed could better tolerate the variation of feedstock price; offering 8% lower cost of energy at 65$/t wood chips.