To provide a system for utilizing chaff as a new resource.

This system functions to produce smoked charcoal C by combusting chaff H and enables hot water to be produced by utilizing the heat generated in the combustion. The system has the following construction: A hopper 1 for reserving the chaff H and feeding the chaff H to a screw conveyor 2 is set upstream of the screw conveyor 2, and in communicating with the downstream end of the screw conveyor 2, there is provided a combustion box 6 having a forward release part 6a and an upward release part 6b and bored with a number of air holes 14 for passing air fed from a blower 7 through the respective inner walls of a double bottom wall 6c and a double sidewall 6d, there is provided right above the combustion box 6 a nearly box-shaped heat exchanger 9 having a lower end opening 9a, and in the vicinity of the heat exchanger 9, there is provided a hot water storage tank 10 equipped with a hot water feed pipe 11 and a hot water returning pipe 12 with hot water circulated through the heat exchanger 9.