Abstract: A pelletized fuel is disclosed, made with cellulosic fiber and thermoplastic resin. Preferred embodiments of the pelletized fuel are adapted to be fed in admixture with coal, into conventional coal fired furnaces using conventional coal handling equipment. The preferred pelletized fuel has appropriate mass density and bulk density, and is shaped such that it maintains a generally uniform admixture with the coal during conventional handling, and, upon combustion, produces heat similar to that of coal, thereby minimizing the process adaptations required to convert a furnace from using a conventional coal fuel supply, to a fuel supply comprising a mixture of coal and the pelletized fuel. The invention comprehends methods of making the pelletized fuel, and methods of firing a furnace using the pelletized fuel.