Economic feasibility of utilizing forest biomass in district energy systems – A review

Recent global protocols and agreements have motivated countries to use biomass for energy generation. However, the barriers in biomass utilization including variations in biomass availability, high moisture content, low bulk density and dispersed distribution of biomass have made investors reluctant to invest in bioenergy projects in some parts of the world. In this paper, in addition to a brief summary of the conversion technologies used for energy generation, a review of the world literature on techno-economic assessment of district energy systems using forest biomass as the primary fuel with references extending over two decades is provided. Although energy generation from forest biomass is found to be expensive in many countries, the review of literature revealed important factors that increased the share of biomass in energy production in other countries. These important factors include using more efficient technologies, providing governmental grants and subsidies, setting new policies in favor of biomass utilization, increasing emission reduction targets, and introducing tradable carbon credits. The feasibility of utilizing forest biomass in district heating systems has been examined in the literature mainly based on the costs, while considering social and environmental profiles of these systems could improve their acceptance. Future research studies on assessing the performance of biomass district energy systems should consider environmental and social impacts of these systems in addition to their costs.