Design of woody biomass energy system considering economics of scale and demand-and-supply equilibrium

Utilization of woody biomass represents an effective alternative to fossil fuels for mitigation of global warming. The purpose of the study is to design woody biomass energy system, and to analyze the effect on the total cost of the energy system and environmental impact derived by installing biomass power plant in rural area in Japan. The energy system consists of woody biomass, logistics, energy conversion, and distribution of both electricity and heat. In order to analyze the comprehensive network of the system, an energy-economic model is developed and applied for the rural area. The model considers the balance between energy conversion sectors and energy demand sectors in long-term taking into account the cost of biomass power generation, price of conventional energy, legal issues, and limits of quantity of biomass supplied in target area. In addition to the feature mentioned above, the energy-economic model derives the cost minimum configuration of the energy system because an open market is supposed in the energy model. As the conversion technology of biomass, direct combustion power plant, and gasified power plant are set in the energy conversion part in the woody biomass energy system; the economic and technological performance of the biomass power plants is evaluated circumstantially. A major issue of preventing woody biomass from the smooth installation is the high cost of biomass resource. Hence, the subsidy is supposed for decreasing the cost of woody biomass in the study, and the effect of the subsidy on the total cost and amount of woody biomass used in the energy system are also evaluated.