JAUE2022-076: Research on the Operation of a Small-Scale Biomass District Heat Supply System for a Group of Houses

Abstract

In recent years, woody biomass has been attracting attention as a renewable energy source. In Japan, power generation systems using woody biomass are also becoming popular. However, energy conversion efficiency is better for heat use than for electricity use. Therefore, heat utilization should be promoted in the future. This study evaluated and analyzed the operation of a wood biomass district heat supply system installed in a group of houses in Kamiyama-cho, Tokushima Prefecture. In this context, a comparison was made before and after maintenance was performed in mid-February 2022, when the strainer was unclogged and the flow rate increased significantly. As a result, it was inferred that the significant increase in flow rate increased the temperature reached by the hot water in each building and reduced the heat loss when supplying heat to the consumer side. However, the underestimation of the temperature difference between the incoming and outgoing temperatures of the plant and the questionnaire confirmed that the heat demand was lower than expected. It was also inferred that the heat loss from the hot water storage tank increased due to the increase in total energy use, confirming that there is room to optimize the flowrate.