Abstract: A solar heated anaerobic digestor is provided, adapted to utilize organic material capable of decomposing to produce methane gas and a liquid fertilizer. The sealed anaerobic digestor is wrapped with a layer of heat absorptive material followed by a series of abutting removable panels of insulative material. Insulative panels may be temporarily removed to expose the heat absorptive material to solar radiation and may be replaced when the solar radiation diminishes. A layer of transparent material wrapped in outwardly spaced relation around the insulatng panels is capable of transmitting solar radiation while providing protection against environmental elements. Additional heating means extending into the digestor provide auxiliary heat as required.