Abstract: A process is provided for the efficient conversion of water-containing organic materials such as bark, peat and sludge as fuels into energy, including drying the materials to convert them into fuels and then combusting the fuels in order to recover as much energy as possible at the lowest possible cost; which comprises heating the material in a steam vessel while enveloping the material in steam at superatmospheric pressure, heating the steam by heat exchange with steam at a higher pressure and higher temperature than the steam in the vessel; mechanically dewatering the material; and then drying the material to convert the material into a fuel, converting water driven from the material into steam, and forming excess steam in the dryer, of which steam all or part is recycled and condensed directly on the material in the steam vessel; and then combusting the dry material in finely divided form in a steam boiler, utilizing the high pressure steam that is generated in a turbine, which in turn operates a generator