jaue2023017: A Woody Biomass District Heat Supply System for a Housing Group -Part1-

Abstract

In Japan, where forest resources are abundant, woody biomass is a locally produced energy for local consumption. Thermal use of woody biomass has a higher energy conversion efficiency than electric use. In addition, since half of the energy consumed by households is heat demand, it has high potential as a supply source. However, there are only a few cases of heat supply with woody biomass to residences, and creating successful examples will be effective for future diffusion. In this study, a wood biomass district heat supply system installed in a housing complex in the town of A, Tokushima Prefecture, was analyzed focusing on the supply flow rate and supply temperature. The onward and return temperature difference was relatively large during the period when the system was operated with the inverter adjusted. However, it did not reach the design assumption. The inverter needs to be operated in a lower range. By increasing the supply temperature, the plant efficiency reached a satisfactory level. On the other hand, the supply efficiency was not improved, which is assumed to be due to heat loss from the piping leading to the heat exchangers in the housing units.